JP2014151799A - Handle production method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a steering wheel production method capable of producing a steering wheel at lower costs and maintaining a shape of a heater wire in a long term.SOLUTION: An inside coating part 20 is formed by filling liquid resin material 35 in an inside coating part molding tool 31 in which a heater wire 21 and a core grid 15a are disposed. Then, a rim part is formed by forming an outside coating part by coating the inside coating part 20 including the heater wire 21. The heater wire 21 can be surely fixed to the inside coating part 20 with less number of manhours, and a steering wheel including the heater wire 21 on the rim part can be produced at lower costs. In addition, a shape of the heater wire 21 is surely maintained in a long term.

Description

  The present invention relates to a method for manufacturing a handle for manufacturing a handle provided in a grip portion that grips a heating element that generates heat when energized.

  In recent years, as part of efforts to protect the global environment and suppress the generation of greenhouse gases, electric vehicles (EVs), which have a lower environmental impact than gasoline engine vehicles, are becoming more popular. In the case of such an electric vehicle, it is composed of a combination of a storage battery and a motor, and basically it is necessary to replenish energy from an external charger, so a measure to suppress the consumption of stored power is essential. Among them, the most effective means is to suppress power consumption for heating (air conditioner) that consumes a large amount of power.

  Therefore, it has been promoted to take a means of directly transmitting warmth by a steering wheel directly touched by an occupant (driver), and as one of them, a configuration in which a heater wire as a heating element is embedded in the steering wheel is known. Yes.

  In other words, a heater device is incorporated into the steering wheel, and even after the start, various engines are not yet warmed up enough to warm the steering wheel, for example, to start an automobile that was parked outdoors in winter. 2. Description of the Related Art There is known a configuration that can suppress the consumption of electric power by suppressing the use of heating while reducing the difficulty of operation and discomfort caused by a cold steering wheel, that is, a steering wheel when driving.

  As such a configuration, for example, a configuration is known in which a heater device in which heater wires are knitted in a lattice shape is attached to the inner surface of the skin portion with a double-sided tape to form an annular shape, and is wound around and fixed to the outer periphery of the rim portion. (For example, refer to Patent Document 1).

  However, in this configuration, it is necessary to sew and decorate a skin body such as leather or synthetic leather so as to cover the heater wire so as not to impair the tactile sensation while covering the heater wire, which is expensive. In addition, in this configuration, the cost of the double-sided tape is required, and it is necessary to separately reinforce the fixing of the heater wire so that the heater wire does not lose its shape due to a decrease in the adhesive strength of the double-sided tape due to aging. There is.

JP 2002-96739 A (page 3-6, FIG. 1)

  As described above, in adopting a steering wheel equipped with a heater device, a configuration that is cheaper and can reliably retain the shape of the heater wire over a long period of time is desired.

  The present invention has been made in view of these points, and an object of the present invention is to provide a method for manufacturing a handle that can manufacture a handle at a lower cost and can reliably retain the shape of a heating element over a long period of time.

  The method of manufacturing a handle according to claim 1 is a method of manufacturing a handle for manufacturing a handle provided in a gripping part for gripping a heating element that generates heat when energized, and for a planned part in which the heating element and a cored bar are installed. Filling the molding die with a liquid resin raw material and molding a planned gripping portion in which the heating element is integrally fixed to the surface portion, and a covering portion covering the planned gripping portion including the heating element And forming a skin part forming the grip part.

  The method for manufacturing a handle according to claim 2 is the method for manufacturing a handle according to claim 1, wherein in the planned portion forming step, a cloth material in which the heating element is integrally fixed to the surface is installed in the mold for the planned portion. A cloth material installation step, a core metal installation step for installing a cored bar in the planned part molding die, and a liquid resin material in the planned part molding die each provided with the heating element and the cored bar. And a molding step of molding the planned grip portion.

  The method for manufacturing a handle according to claim 3 is the method for manufacturing a handle according to claim 1 or 2, wherein the gripping portion is a core layer that covers at least a part of the core metal with a smaller thickness on the other side than the one side. And a surface layer covering the core layer, and the planned portion molding step is performed by filling at least one core metal mold by filling a liquid core layer resin raw material into the core layer molding die in which the core metal is installed. A core layer forming step for forming the core layer so as to cover a portion, a heating element installation step for installing a heating element in a surface layer mold, and a core that covers at least a part of the core metal in the surface layer mold An intermediate body having a layer is installed so as to form a wider flow path between the other side of the core layer and the surface layer mold than between one side of the core layer and the surface layer mold. Using the intermediate channel installation step and the flow path, The surface layer resin material for the liquid is filled in which and a surface layer forming step of forming the surface layer.

  The method for manufacturing a handle according to claim 4 is a method for manufacturing a handle for manufacturing a handle provided in a grip portion for gripping a heating element that generates heat when energized, and the handle is manufactured in a mold for a planned portion in which a mandrel is installed. A planned portion molding step of filling a liquid resin raw material to mold a planned grip portion, and a carrier holding the heating element is wound around the surface of the planned grip portion, and the heat generating body is transferred to the surface of the planned grip portion A transfer step, and a skin portion forming step of forming the skin portion by covering the planned grip portion including the heating element to form the skin portion.

  According to the method for manufacturing a handle according to claim 1, a planned holding portion is formed by filling a liquid resin raw material in a molding die for a planned portion in which a heating element and a cored bar are installed, and the grip including the heating element is formed. By forming the skin part by covering the planned part, it is possible to reliably fix the heating element to the scheduled gripping part with less man-hours and to make the handle with the heating element cheaper. In addition to being able to be manufactured, it is difficult for the heating element to lose its shape, and the heating element can be reliably retained for a long period of time.

  According to the method for manufacturing the handle according to claim 2, in addition to the effect of the method for manufacturing the handle according to claim 1, the heating element is fixed to the surface of the cloth material and is installed on the molding die for the planned portion. By forming the heating element integrally with the planned holding portion, the workability when the heating element is installed in the planned portion molding die is better.

  According to the method for manufacturing a handle according to claim 3, in addition to the effect of the method for manufacturing the handle according to claim 1 or 2, a core layer having a smaller thickness on the other side is formed relative to one side, and the core layer is By installing the intermediate body provided so as to form a wider flow path between the other side of the core layer and the mold for the planned portion than between one side of the core layer and the mold for the planned portion, Using this flow path, the resin material for the surface layer can be effectively and uniformly poured into the molding die for the planned portion, and the surface layer can be reliably molded with a good appearance without causing a lack of thickness.

  According to the method for manufacturing a handle according to claim 4, a planned holding part is formed by filling a liquid resin raw material into a molding die for a planned part in which a mandrel is installed, and the carrier holding the heating element is held in the planned holding part. The heating element is transferred to the surface of the scheduled gripping part, and the gripping part is formed by covering the planned gripping part including the heating element and forming a skin part, thereby holding the heating element. The handle can be securely fixed to the part with less man-hours, the handle provided with the heating element in the gripping part can be manufactured at a lower cost, and the heating element is less likely to lose its shape, and the heating element can be reliably retained for a long period of time. .

BRIEF DESCRIPTION OF THE DRAWINGS It is a perspective view which shows typically 1st Embodiment of the manufacturing method of the handle | steering_wheel of this invention, (a) shows the cloth material which provided the heat generating body on the surface, (b) shows the cloth material installation process. , (C) shows a mandrel installation process, and (d) shows a molding process. It is a perspective view which shows a part of shaping | molding die for scheduled parts same as the above. It is a top view which shows typically the manufacturing method of a handle same as the above, (a) shows a cloth material installation process, (b) shows a mandrel installation process, (c) shows a forming process. It is a perspective sectional view showing a part of a handle same as the above. It is a top view which shows a handle same as the above. It is sectional drawing which shows typically 2nd Embodiment of the manufacturing method of the handle | steering_wheel of this invention, (a) shows a heat generating body positioning process and a core metal installation process, (b) shows a formation process. It is a perspective view which shows a heat generating body unit same as the above. It is a perspective view which shows the support body of a heat generating body unit same as the above. It is a perspective view which shows a part of heat generating body unit of 3rd Embodiment of the manufacturing method of the handle | steering_wheel of this invention. It is a top view which shows a part of heat generating body unit of 4th Embodiment of the manufacturing method of the handle | steering_wheel of this invention. It is a top view which shows typically 5th Embodiment of the manufacturing method of the handle | steering_wheel of this invention, (a) shows a heat generating body installation process, (b) shows a metal core installation process, (c) is A molding process is shown. It is a perspective view which shows a holding member same as the above. It is a top view which shows a part of shaping | molding die for scheduled parts same as the above. It is a perspective view which shows a part of shaping | molding die for scheduled parts which hold | maintained the heat generating body with the holding member in the heat generating body installation process same as the above. It is sectional drawing which shows the shaping | molding die for scheduled parts which installed the heat generating body and the core metal same as the above. It is sectional drawing of the holding part of a handle same as the above. It is a top view which shows a part of shaping | molding die for scheduled parts of 6th Embodiment of the manufacturing method of the handle | steering_wheel of this invention. It is sectional drawing which shows typically 7th Embodiment of the manufacturing method of the handle | steering_wheel of this invention, (a) shows a heat generating body installation process and a metal core installation process, (b) is a 1st demolding process. Indicates. It is a perspective view which shows a part of the shaping | molding die for schedule parts which hold | maintained the heat generating body with the holding member in the heat generating body installation process of 8th Embodiment of the manufacturing method of the handle | steering_wheel of this invention. The heating element is shown, wherein (a) is a plan view of the heating element, and (b) is a cross-sectional view at a position corresponding to II in (a). It is a top view which shows typically 9th Embodiment of the manufacturing method of the handle | steering_wheel of this invention, (a) shows a core layer shaping | molding process, (b) shows a surface layer shaping | molding process. (A) is sectional drawing which shows a core layer shaping | molding process typically, (b) is sectional drawing which shows a surface layer shaping | molding process typically. It is sectional drawing which shows typically 10th Embodiment of the manufacturing method of the handle | steering_wheel of this invention, (a) shows a winding process, (b) shows a heating process, (c) is a peeling removal process. (D) shows an epidermis part formation process. It is explanatory drawing which shows typically the mounting | wearing apparatus used for a heating element provision process and this heating element provision process same as the above.

  Hereinafter, a first embodiment of a method of manufacturing a handle according to the present invention will be described with reference to the drawings.

  In FIG. 5, reference numeral 10 denotes a steering wheel which is a steering wheel of an automobile as a vehicle, for example. The steering wheel 10 is a steering wheel body 11 which is a steering wheel body, and a pad body which is mounted on the passenger side of the steering wheel body 11. An airbag device (airbag module) 12 as a center pad and a switch module (not shown) are provided. The steering wheel 10 is normally mounted on a steering shaft provided in the vehicle in an inclined state. Hereinafter, the occupant side of the airbag device 12, that is, the front side is the upper side (in the direction of the arrow U), and the steering shaft side That is, the description will be made assuming that the rear side is the lower side (in the direction of arrow D), the front side of the vehicle, that is, the windshield side above the front side is the front side, and the rear side of the vehicle, ie, the lower side on the rear side.

  The steering wheel body 11 is formed at least partially along the circumference. In this embodiment, the steering wheel body 11 is a rim portion (ring portion) 15 serving as an annular gripping portion, and an inner side of the rim portion 15. The boss portion 16 is positioned, and a plurality of spoke portions 17 are connected in the present embodiment to connect the rim portion 15 and the boss portion 16. In addition, a substantially cylindrical boss 18 having a serration structure that meshes with the steering shaft is provided at a lower portion on the vehicle body side of the boss portion 16, and a core body also called a hub core is formed on the boss 18 The boss plate 19 is integrally fixed by molding, for example, a magnesium alloy by a gravity casting method, an injection molding method, or the like. Further, a resin lower cover (not shown) called a back cover or a body cover is attached to the boss portion 16 to cover the lower side portion of the boss portion 16. Then, the metal core 17a of the spoke portion 17 is integrally extended from the boss plate 19 or fixed by welding or the like. Further, the core metal 15a of the rim part 15 is fixed to the core metal 17a of the spoke part 17 by welding or the like.

  Further, as shown in FIGS. 1 to 5, a soft surface is formed on the surface side of the entire circumference of the core metal 15a of the rim portion 15 and the surface side of the core portion 17a of the spoke portion 17 on the rim portion 15 side. An inner covering portion 20 which is a core covering portion as a planned holding portion made of synthetic resin or the like is formed. A cloth material 22 having a heater wire 21 as a heating element that generates heat when energized is integrally disposed on the surface of the inner covering portion 20. Further, the inner covering portion 20 and the heater wire 21 are covered with an outer covering portion 23 which is a top covering portion as a thin skin portion.

  In the present embodiment, for example, a soft foamed polyurethane resin that is finely foamed is used as the inner covering portion 20.

  The heater wire 21 is provided with an insulating film on the surface of a core wire that is a resistance wire containing nickel or the like, which generates heat when energized. In the present embodiment, for example, the wire diameter is set to about 1.0 mm. ing. The heater wire 21 is connected to a control circuit (not shown), and is configured to generate heat when energized by the control circuit.

  In the present embodiment, for example, a polyester sheet-like non-woven fabric is used as the cloth material 22. The cloth material 22 is formed in, for example, a square shape, and the heater wire 21 is fixed to the surface 22a. In the present embodiment, on the surface 22a of the fabric material 22, the heater wire 21 is repeatedly folded back and forth alternately in a direction intersecting the longitudinal direction of the fabric material 22 that is the circumferential direction of the rim portion 15, for example. It is fixed in a state, that is, in a wavy shape so as to meander (FIG. 1A). The cloth material 22 is arranged in the inner covering portion 20 together with the heater wire 21 at a position corresponding to, for example, the outer peripheral side of the rim portion 15.

  In the present embodiment, the outer covering portion 23 may be made by finely foaming a soft polyurethane resin (low yellowing type or non-yellowing type polyurethane) that does not change color due to, for example, ultraviolet rays. The outer covering portion 23 is insert-molded (overmolded) on the surface of the inner covering portion 20.

  The airbag device 12 includes a bag-shaped airbag, a resin cover body that covers the folded airbag, an inflator that injects gas, and the like. Gases are rapidly injected into the interior, the folded and stored airbag is rapidly inflated, the cover body is cleaved, and the airbag is inflated and deployed on the front side of the occupant to protect the occupant. The airbag device 12 may be integrated with a horn switch mechanism as a switch device.

  The steering wheel 10 is molded using an inner covering portion molding die 31 that is a predetermined portion molding die and an outer covering portion molding die that is not shown.

  The inner covering portion molding die 31 includes a first first half mold 33 and a first other half mold 34. The first first half mold 33 and the first other half mold 34 In the front view in a circular cross section filled with a liquid resin raw material 35 which is a reaction mixture liquid (for example, a liquid mixture of isocyanate and polyol (and antioxidant, colorant, etc.)) that reacts to become polyurethane. A (first) cavity 36 that is an annular (first) space is formed. That is, the first first half mold 33 facing the first other half mold 34 is provided with a first cylindrical molding surface 33a having a semi-cylindrical surface shape. For example, a first other molding die 34a having a semi-cylindrical surface shape that is axisymmetric to the first first molding surface 33a is formed in the first other half die 34 that is opposed. In the present embodiment, the first half mold 33 is the outer peripheral side of the rim portion 15, and the first other half mold 34 is the inner peripheral side of the rim portion 15. Further, the inner covering portion molding die 31 is used for further mixing the first mixing head (not shown) for mixing and stirring and discharging the resin raw material 35 and the resin raw material 35 discharged from the first mixing head. The first after-mixer 37, and the first gate 38 into which the resin raw material 35 mixed by the first after-mixer 37 is injected into the cavity 36 is, for example, the first half mold 33. It is formed continuously on one molding surface 33a.

  The first after-mixer 37 is provided with a plurality of bent resin flow paths 37a so that the resin raw material 35 is well mixed by the split flow and the subsequent merge (FIG. 2).

  The first gate 38 is also called a fan gate or the like, and is formed so as to gradually expand from the first aftermixer 37 side to the cavity 36 side. At the position of the first gate 38, a notch 22b formed in a notch on one side of the cloth material 22 disposed in the cavity 36 is located opposite to the first gate 38. In the present embodiment, the first gate 38 corresponds to, for example, the lower side of the inner covering portion molding die 31, that is, when the inner covering portion molding die 31 is viewed from the front, at 6 o'clock of an analog timepiece. (FIGS. 2 and 3).

  Similarly to the inner covering portion forming die 31, the outer covering portion forming die includes a second first half die and a second other half die. Between the second other half molds, a (second) cavity that is a circular (second) space with a circular cross-section and filled with the resin raw material is formed, and the resin raw material is A second mixing head (not shown) for mixing and stirring and discharging, and a second aftermixer for further mixing the resin raw material discharged from the second mixing head, are provided by the second aftermixer. A second gate through which the mixed resin material is injected into the cavity 36 is formed continuously on the second first molding surface of the second first half mold, for example. Note that the detailed configuration of each part of the outer covering portion forming die is the same as that of the inner covering portion forming die 31, and thus the description thereof is omitted.

  When the steering wheel 10 is manufactured, a cloth material 22 having a heater wire 21 fixed to the surface 22a is prepared in advance, and the cloth material 22 is formed in a sectional shape of the cavity 36, which is the first first embodiment in the present embodiment. Pre-shaped so as to be curved into a semi-cylindrical surface along the first first molding surface 33a, which is the inner surface shape of the half mold 33, and installed on the first first molding surface 33a (cloth material installation step) (FIG. 1 (b) and FIG. 3 (a)). At this time, the cloth material 22 faces the surface 22a to which the heater wire 21 is fixed toward the first other half die 34, in other words, on the side where the heater wire 21 is opposite to the first molding surface 33a. It is installed so that it is positioned and the notch 22b faces the first gate 38. Therefore, the cloth material 22 is located between the first first molding surface 33a and the heater wire 21.

  Next, after the core bars 15a and 17a integrated with the boss plate 19 and the like are placed on the first half die 33 (core bar installation step (FIGS. 1C and 3B)), the first The first half mold 33 and the first other half mold 34 are matched (mold closed) to form a cavity 36, and the resin material 35 discharged from the first mixing head is fed to the first aftermixer 37. The resin flow path 37a (FIG. 2) is stirred and mixed, and filled into the cavity 36 through the first gate 38, whereby the resin raw material 35 reacts in the cavity 36 to become polyurethane, and the inner covering portion 20 is Molding (molding process (FIGS. 1D and 3C)). At this time, since the cloth material 22 provided with the heater wire 21 is preshaped along the first first molding surface 33a, the distance between the cloth material 22 and the first first molding surface 33a. Is very narrow, and the distance between the metal core 15a and the fabric material 22 (heater wire 21) is larger than the distance between the fabric material 22 and the first first molding surface 33a, and the first Once a large amount of resin raw material 35 is poured between the core metal 15a and the cloth material 22 from the gate 38, the resin raw material 35 flows along the outside of the core metal 15a (outside of the cloth material 22). The flow is completed toward the flow end (the position of the analog clock 12 o'clock corresponding to the upper side of the rim portion 15) 35 with foaming. Further, the resin raw material 35 emits reaction heat during the reaction, and a part thereof is impregnated into the eyes of the cloth material 22, so that the resin raw material 35 is firmly fixed to the inner covering portion 20 by the anchor effect without using an adhesive or the like. In this way, the above-described installation process and molding process constitute an inner coating part forming process that is a planned part molding process for molding the inner coating part 20 in which the heater wire 21 is integrally fixed to the surface. Then, the first first half mold 33 and the first other half mold 34 are opened, and the intermediate body M1 on which the inner covering portion 20 is formed is removed from the mold (first demolding step). At the time of this demolding, the cloth material 22 is substituted for the mold release agent, and the intermediate M1 can be easily removed from the inner cover mold without spraying the mold release agent on the molding surfaces 33a, 34a and the like in advance. Demolding is possible.

  Thereafter, the removed intermediate body M1 is inserted into, for example, an in-mold coated outer covering mold, and the second first half mold and the second other half mold are matched (mold closing). The cavity is formed, and the resin raw material discharged from the second mixing head is stirred and mixed by the resin flow path of the second aftermixer, and filled into the cavity of the outer cover mold through the second gate. Thus, the resin raw material reacts in the cavity to become polyurethane, and the outer covering portion 23 is formed so as to cover the entire surface of the inner covering portion 20 (outer covering portion forming step which is a skin portion forming step). Then, the second first half mold and the second other half mold are opened, and the steering wheel 10 is demolded (second demolding step). Thereafter, various surface treatments are performed as necessary.

  The steering wheel 10 molded in this way is a polyurethane steering wheel that has good surface temperature rise and tactile sensation, and that the heater wire 21 is not incorporated from the appearance (it is difficult to understand).

  According to the present embodiment, the inner covering portion 20 is formed by filling the liquid resin raw material 35 in the inner covering portion forming die 31 in which the heater wire 21 and the core metal 15a are installed. By forming the rim portion 15 by covering the inner covering portion 20 including the outer covering portion 23, the heater wire is sewn or adhered to the surface of the inner covering portion, for example. Thus, the heater wire 21 can be securely fixed to the inner covering portion 20 with less man-hours, and the steering wheel 10 provided with the heater wire 21 on the rim portion 15 can be manufactured at a lower cost, and the heater wire 21 loses its shape. The heater wire 21 can be reliably retained for a long period of time.

  Specifically, the heater wire 21 is fixed to the surface 22a of the cloth material 22 in advance and placed on the inner covering portion molding die 31, and the heater wire 21 is integrally formed with the inner covering portion 20 together with the cloth material 22 (insert molding). Thus, the workability when the heater wire 21 is installed in the inner covering portion forming die 31 is better.

  In addition, since the cloth material 22 is disposed so as to wrap around the heater wire 21 and the cloth material 22 is interposed between the heater wire 21 and the outer covering portion 23, the heat generated from the heater wire 21 is a heat retaining effect of the cloth material 22. Therefore, it is difficult to be absorbed by the outer covering portion 23, and the target temperature can be quickly reached.

  Moreover, since the cloth material 22 functions as a substitute for the mold release agent when the intermediate body M1 is removed from the inner cover mold as described above, the cost of the mold release agent becomes unnecessary, and the mold release agent. It is not necessary to perform the work process of applying the coating or cleaning the release agent adhering to the intermediate M1 after demolding, and the steering wheel 10 can be manufactured at a lower cost.

  Further, when molding the inner covering portion 20, the cloth material 22 and the inner covering portion 20 can be welded easily and without using an adhesive or the like by the heat of the resin raw material 35 flowing into the cavity 36. Thus, the cost and the bonding process are not required, and the steering wheel 10 can be manufactured at a lower cost, and the heater wire 21 fixed to the cloth material 22 can be reliably retained.

  Further, since the warmed fabric material 22 is molded so as to wrap around the heater wire 21, the surface of the inner covering portion 20 is less likely to be uneven, and the unevenness feeling when the inner covering portion 20 is covered by the outer covering portion 23. Is less likely to occur, resulting in a better appearance.

  In addition, since the heater wire 21 is embedded inside the inner sheath portion 20, the urethane foam constituting the inner sheath portion 20 serves as a protector for the heater wire 21, and ensures that the heater wire 21 is not damaged. In addition to being able to prevent this, even if the surface of the inner covering portion 20 is covered with the outer covering portion 23, the outer covering portion 23, that is, the rim portion 15, is less likely to be uneven, and the appearance and feel are improved. Therefore, the material of the outer covering portion 23 can be selected widely, and even if the outer covering portion 23 is formed thin, the appearance is not hindered.

  Since the inner covering portion 20 and the outer covering portion 23 are formed of a resin whose thermal conductivity is lower than that of a metal, the heat generated by the heater wire 21 is transmitted through the inner covering portion 20 and the outer covering portion 23 to the core bars 15a and 17a. It is difficult to escape to the side, and the rim portion 15 can be warmed more reliably.

  Next, a second embodiment will be described with reference to FIGS. In addition, about the structure and effect | action similar to said 1st Embodiment, the same code | symbol is attached | subjected and the description is abbreviate | omitted.

  In the manufacturing method of the steering wheel 10 according to the second embodiment, a heater unit 43 as a heating element unit in which a heater wire frame 41 composed of a plurality of heater wires 21 is held by a support 42 is covered with an inner coating. The inner covering part 20 is formed by being attached to the part molding die 31.

  Each heater wire 21 is formed to have a wire diameter of, for example, 1.0 to 3.0 mm (1.0 mm to 3.0 mm), more preferably 1.0 to 2.0 mm (1.0 mm to 2.0 mm). Has been. In addition, these heater wires 21 have, for example, a shape other than a perfect circle, for example, a shape having a corner such as a triangle or a quadrangle so that the heater wire frame 41 does not rotate when held by the support 42, or In this embodiment, for example, an elliptical shape (oval shape) is used. The heater wire 21 may have a cross section of the core wire itself having a triangular shape, a quadrangular shape, an elliptical shape, or the like. Alternatively, the cross section of the core wire may be a circular shape or the like. It is good also as a shape, square shape, or an elliptical shape. The heater wires 21 are selected so as to have high hardness and are difficult to be deformed by the molding pressure of the resin raw material 35 filled in the inner covering portion molding die 31.

  The heater wire frame 41 is mechanically and electrically connected to each other by connecting portions 44 extending in a direction intersecting the longitudinal direction of the heater wires 21 at both ends of each heater wire 21 arranged along the circumferential direction of the rim portion 15. Are connected to each other (FIG. 7). In other words, in the heater wire frame 41, the heater wires 21 are arranged in parallel with each other at positions extending from the outer periphery to the inner periphery on the rear side (front side), which is the occupant side of the rim portion 15. Here, the interval between the heater wires 21 is, for example, a predetermined constant interval of 10 mm or less, preferably 5 to 10 mm (5 mm or more and 10 mm or less). The heater wire frame 41 is curved in a semi-cylindrical surface along the cross-sectional shape of the rim portion 15.

  The connecting portion 44 may be protected by a protective member such as a nonwoven fabric using, for example, solder.

  For the support 42, for example, a thermoplastic resin such as ABS can be suitably used, but in order to improve the tactile sensation of the steering wheel 10, it is preferable to use a member having rubber properties such as urethane. The support 42 is fixed to the heater wire frame 41 (heater wire 21), a support body 46 that supports lead wires 45, 45 that are electrically connected to a power source (not shown), and the inner covering portion molding die 31. The fixed portion 47 is integrally provided, and is disposed, for example, on the spoke portions 17 located on both sides of the steering wheel 10 (FIGS. 6 and 8).

  The support portion main body 46 includes a first support portion divided body 46a located on the front side (rear side) which is the non-occupant side, and a second support portion divided body 46b located on the rear side (front side) which is the occupant side. The first support part split body 46a and the second support part split body 46b are detachably connected and fixed to each other via an insertion pin (not shown). In addition, the support portion body 46 includes a positioning hole 49 for positioning the heater wire 21 corresponding to the innermost peripheral side of the rim portion 15 in the heater wire frame 41, and a lead wire positioning for positioning the lead wires 45, 45. Groove portions 51 and 51 are provided. The support body 46 includes positioning notches 52 and 52 for positioning the support 42 with respect to the inner covering portion molding die 31 at the upper and lower portions of the second support portion split body 46b. Notches are formed.

  The positioning hole 49 can have an arbitrary shape corresponding to the cross-sectional shape of the heater wire 21, but in the present embodiment, for example, has a cross-sectional elliptical shape (a cross-sectional oval shape). Further, the positioning hole 49 is formed so as to penetrate the support portion main body 46 in the vertical direction, and is divided into approximately equal halves in the front-rear direction by the support portion split bodies 46a and 46b. Further, the positioning hole 49 is located closer to the rim portion 15 side of the steering wheel 10, which is one end side of the support body 42.

  Each lead wire positioning groove portion 51 leads one end side of each lead wire 45 to the boss portion 16 side and leads the other end side of each lead wire 45 to the rim portion 15 side, and one end side is the first support. The part divided body 46a is opened to the front side of the second support part divided body 46b at a position near the lower part of the center side of the steering wheel 10, and the other end side is the upper and lower ends of the support body 42 and the steering wheel 10 is located above the positioning hole 49. Is located between the support part divided bodies 46a and 46b, and is mainly formed in the first support part divided body 46a between the one end side and the other end side. .

  Each positioning notch 52 is formed by fitting a positioning projection (not shown) for positioning, for example, projecting from the first half mold 33 of the inner covering portion molding die 31, for example. 31 (first half mold 33) is used to position the support 42, and is positioned closer to the center of the steering wheel 10 than the positioning holes 49 and the lead wire positioning grooves 51. It is cut out in a triangular shape that gradually narrows upward or downward with respect to the center position in the direction.

  Further, the fixed portion 47 forms the center side of the steering wheel 10 which is the other end side of the support body 42, and is continuous to the second support portion divided body 46 b of the support portion main body 46 via the thin portion 55. The fixed portion main body 47a to be fixed and the fixed body 47b positioned opposite to the upper portion on the front side of the fixed portion main body 47a are divided into two. That is, the to-be-fixed part main body 47a is integrally shape | molded via the 2nd support part division body 46b and the thin part 55. FIG. A magnet 57 as one fixing member is fitted in a recess (not shown) formed inside the fixed body 47b, and the magnet 57 is stored between the fixed body 47b and the fixed portion main body 47a. ing. The fixed body 47b is detachably connected and fixed to the fixed portion main body 47a via an insertion pin (not shown). Further, the fixed body 47b is substantially flush with, for example, the first support part divided body 46a.

  The thin portion 55 is a weak portion formed linearly along the vertical direction along the boundary between the support portion main body 46 and the fixed portion 47, and the front side of the thin portion 55 is from the rear side to the front side. A notch 59 that gradually expands is formed. The cut portion 59 is not embedded in the resin raw material 35 constituting the inner covering portion 20 in a state where the support 42 is in close contact with the core metal 17a of the spoke portion 17, and the thin portion 55 At this position, the fixed portion 47 can be separated from the support portion main body 46 side.

  The magnet 57 generates an attracting force due to a magnetic force between the magnet 57 and the magnet 61 disposed in the fixed recess 60 formed in the first half mold 33 of the inner covering portion molding die 31, for example. The support 42 (and the heater wire frame 41 supported by the support 42) can be locked and fixed to the inner covering portion forming die 31. As the magnet 57, for example, a neodymium magnet having a high magnetic flux density and a size of 10 mm square and an attractive force of 10 kgw or more is used in consideration of the size and the strength of the magnetic force.

  A fixing plate 63 for holding the magnet 61 is fitted in the fixing recess 60. The fixing plate 63 is fixed so as to form a design surface substantially flush with the periphery of the fixing recess 60 of the inner covering portion forming die 31 (first first half die 33) while the magnet 61 is pressed. The recess 60 is fitted. Further, the fixing plate 63 is formed by the inner covering portion forming die 31 (the first covering die 31) by means of a screw (not shown) disposed at a position other than the design surface of the inner covering portion forming die 31 (the first first half die 33). It is fixed to one half mold 33).

  When manufacturing the steering wheel 10, first, the heater wire 21 of the heater wire frame 41 preliminarily shaped into a semi-cylindrical surface by connecting the heater wire 21 with the connecting portion 44 is used as the positioning hole of the support 42. At 49, the support part divided bodies 46a and 46b are sandwiched, and the lead wires 45 are fitted into the lead wire positioning groove parts 51, and the support part split bodies 46a and 46b are connected and fixed by insertion pins. In this state, since the cross-sectional shape of the heater wire 21 is not a perfect circle, the heater wire frame 41 is fixed at a predetermined angle without rotating with respect to the support 42. Further, the fixed body 47b in which the magnet 57 is fitted in the concave portion is connected and fixed to the fixed portion main body 47a formed integrally with the second support portion divided body 46b by an insertion pin, and the magnet 57 is covered. It is sandwiched between the fixing portion main body 47a and the fixing body 47b.

  In this state, the support 42 has the positioning notches 52 and 52 fitted to the positioning projections of the inner covering portion molding die 31, and the magnet 57 is fixed to the first half die 33. By pulling it together with the magnet 61, the support 42 is fixed to the first half mold 33 in a predetermined position. In this state, the heater unit 43 is held at a position where the heater wire frame 41 is spaced inward by, for example, about 2 to 3 mm from the first first molding surface 33a of the first half mold 33. (Heater wire positioning step (FIG. 6A)).

  Next, in the same manner as in the first embodiment, the core bars 15a and 17a integrated with the boss plate 19 and the like are placed on the first half mold 33 (the core bar installation step (FIG. 6A)). )), The first half mold 33 and the first other half mold 34 are matched (mold closed) to form a cavity 36, and the resin material 35 discharged from the first mixing head By stirring and mixing through the resin flow path 37a of the first after-mixer 37 and filling the cavity 36 through the first gate 38, the resin raw material 35 reacts in the cavity 36 to become polyurethane, and the heater wire 21 Is formed (molding step (FIG. 6B)).

  Thereafter, the intermediate body M1 is removed from the inner covering portion molding die 31, and the support body 42 has the fixed portion 47 attached to the support portion main body 46 at the position of the thin portion 55 that is not covered by the inner covering portion 20. The magnet 57 is collected by breaking it. The magnet 57 can be reused.

  Next, as in the first embodiment, the outer covering portion 23 is formed so as to cover the entire surface of the inner covering portion 20 using the outer covering portion forming mold, and the second first half die The second other half mold is opened and the steering wheel 10 is removed.

  In this way, the heater wire 21 is preliminarily framed as a heater wire frame assembly 41, installed on the inner covering portion molding die 31 via the support 42, and integrally formed with the inner covering portion 20 (insert molding). The workability at the time of installing the wire 21 on the inner covering portion forming die 31 is good, and the heater wire 21 can be securely fixed to the inner covering portion 20 with fewer man-hours.

  Further, the linear heater wires 21 are separated from each other, and the heater unit 43 is installed in the inner covering portion molding die 31 so that the heater wires 21 are positioned along the circumferential direction that is the flow direction of the resin raw material 35. Since the flow resistance of the resin raw material 35 in the cavity 36 is low and molding can be performed, and anything other than the heater wire 21 that obstructs the flow of the resin raw material 35 is not inserted, the outer appearance of the inner covering portion 20 after molding is air bubbles, lack of wall, etc. Can be suppressed. In addition, the heater wire 21 is not easily pushed by the flow pressure of the resin raw material 35, and the heater unit 43 is formed by fitting the positioning notches 52 and 52 of the support 42 and the positioning convex portion of the inner covering portion molding die 31. Since the positioning is firmly performed, the displacement of the heater wire 21 can be more effectively suppressed.

In particular, the injection pressure of the resin material 35 into the cavity 36 is set to 10 kg / cm ² or less, and this injection pressure is received most in the vicinity of the first gate 38, so By arranging the heater units 43 at positions on both sides of the separated rim portion 15, the heater wire 21 does not directly receive a large injection pressure. Further, since the foaming pressure of the resin raw material 35 constituting the inner covering portion 20 is about several kg, the positional deviation of the heater wire 21 due to this foaming pressure can be set by appropriately setting the foaming direction and the flow direction. Hard to occur.

  On the other hand, by setting the distance between the heater wires 21 of the heater wire frame 41 to 10 mm or less, when the rim portion 15 is gripped, it is difficult for the occupant (driver) to feel the location where the temperature rise in the rim portion 15 is slow. It is difficult to experience unevenness.

  Furthermore, by making the cross section of the heater wire 21 into a shape other than a perfect circle, for example, an elliptical shape, the heater wire frame 41 is fixed to the support 42 with the heater wire 21 held by the positioning hole 49 of the support 42. The heater wire 21 does not rotate at the position. Accordingly, the heater wire 21 (heater wire frame 41) can be securely fixed to the inner covering portion molding die 31 at a target angle, and a part of the heater wire 21 (heater wire frame 41) can be fixed to the inner cover portion 20. It can be surely prevented from being exposed to the surface.

  Further, the magnet 61 used for the inner covering portion forming die 31 is not directly embedded in the inner covering portion forming die 31 but is simply held by the fixing plate 63. For example, when the magnetic force of the magnet 61 becomes weaker Can be easily replaced.

  In addition, the heaters 43 are positioned and fixed by the magnets 57 and 61 and the shapes of the positioning notches 52 and 52 and the positioning projections, and the heater wire 21 is arranged as the heater wire frame 41. Compared with the case where the heater wire 21 is arranged alone, it is possible to more reliably prevent the heater wire 21 from being twisted or displaced. Therefore, uniform temperature adjustment is possible in the rim portion 15.

  In addition, although the inner coating portion 20 increases the amount of resin, since the heater wire frame 41 plays a role of preventing the resin from shrinking with time, a separate member such as a rib for preventing shrinkage is unnecessary or can be minimized. become.

  In the second embodiment, the heater wires 21 of the heater wire frame assembly 41 are connected and fixed by a plurality of linear bridging members 66 as in the third embodiment shown in FIG. In addition, the shape retention of the heater wire 21 can be improved, and the heater wire 21 can be more reliably prevented from being deformed against the flow pressure and foaming pressure of the resin raw material 35. At this time, these bridging members 66 can be more suppressed in flow resistance of the resin raw material 35 by arranging them substantially parallel to each other along a direction intersecting in an inclined manner, rather than in a direction orthogonal to the heater wire 21. The influence on the appearance quality can be further reduced.

  In the second and third embodiments described above, for example, the depth for allowing the resin raw material 35 to flow into the support body 46 of the support 42 as in the fourth embodiment shown in FIG. A resin flow path 68 having a thickness of 1.0 mm or less is formed, or a through hole 69 communicating with the resin flow path 68 is formed through the support part divided bodies 46a and 46b. It is also possible to increase the contact area with 42 and fix the support 42 more stably.

  Further, in the second to fourth embodiments described above, the heater wire frame 41 is arranged only at both side positions (3 to 9 o'clock position of the analog timepiece) of the rim portion 15 that are frequently gripped during operation. However, the heater wire 21 can be arranged so that the temperature can be adjusted over a wider range by changing the design.

  Next, a fifth embodiment will be described with reference to FIGS. In addition, about the structure and effect | action similar to said each embodiment, the same code | symbol is attached | subjected and the description is abbreviate | omitted.

  In the manufacturing method of the steering wheel 10 according to the fifth embodiment, the heater wire 21 is attached to each of the first half die 33 and the first other half die 34 of the inner covering portion molding die 31. The inner covering portion 20 is molded in a state of being sandwiched and fixed by the holding member 71.

  The holding member 71 should also be referred to as a fitting part, and is formed of, for example, an elastic member. The holding member main body 73 that is a pressing portion and an engaging portion that protrudes from the holding member main body 73 are used. A stop projection 74 is integrally provided (FIG. 12). The holding member 71 is separated from each of the first first half mold 33 and the first other half mold 34 of the inner covering portion forming mold 31 by a plurality of, for example, substantially evenly in the circumferential direction. It is designed to be attached at four places (FIGS. 13 to 15).

  The holding member main body 73 is formed in, for example, a rectangular plate shape, and the first first molding surface 33a of the first first half mold 33 and the first other molding surface of the first other mold half 34. The heater wire 21 is sandwiched between and held by 34a.

  Each latching protrusion 74 is a latching recess provided on the first first molding surface 33a of the first one half mold 33 and the first other molding surface 34a of the first other half mold 34. By being press-fitted into each of the recesses 76, the holding member 71 is locked to the first one half mold 33 and the first other half mold 34, from one main surface of the holding member main body 73. It protrudes into a pin shape (columnar shape). Therefore, these locking projections 74 protrude from the surface of the inner covering portion 20 after the inner covering portion 20 is formed.

  When the steering wheel 10 is manufactured, first, the first first molding surface 33a of the first first half mold 33 and the first other molding surface 34a of the first other mold half 34 are firstly formed. Each of the first and second heater wires 21 is installed, and each of the locking projections 74 is press-fitted into the locking recess 76 while covering the holding member main body 73 of each holding member 71 from above the heater wire 21. The heater wire 21 is held between the molding surface 33a and the first other molding surface 34a and the holding member main body 73 (heater wire installation step as a heating element installation step (FIGS. 11A and 14)). . At this time, for example, one heater wire 21 extends along a virtual semi-cylindrical surface equivalent to the first first molding surface 33a and the first other molding surface 34a a plurality of times along the circumferential direction. Preliminarily shaped and placed in a state of being rotated while being shifted.

Next, in the same manner as in the first embodiment, the core bars 15a and 17a integrated with the boss plate 19 and the like are placed on the first half mold 33 (the core bar installation step (FIG. 11B)). And FIG. 15)), the first half mold 33 and the first other half mold 34 are matched (mold closed) to form a cavity 36, and the resin discharged from the first mixing head The raw material 35 is stirred and mixed by the resin flow path 37a of the first aftermixer 37 and filled into the cavity 36 through the first gate 38 (molding step (FIG. 11 (c))). Reacts in the cavity 36 to become polyurethane, and the inner covering portion 20 including the heater wire 21 is molded. At this time, the resin raw material 35 is preferably low-pressure molded at an injection pressure of, for example, several kg / cm ² in order to make it difficult for the heater wire 21 to be displaced or bent during molding.

  Thereafter, the intermediate body M1 is removed from the inner covering portion molding die 31, and the locking projections 74 of the holding members 71 protruding from the surface of the inner covering portion 20 are formed on the molding surface of the inner covering portion 20, respectively. Cut along.

  Next, as in the first embodiment, the outer covering portion 23 is formed so as to cover the entire surface of the inner covering portion 20 using the outer covering portion forming mold, and the second first half die The second other half mold is opened and the steering wheel 10 is removed. At this time, the heater wire 21 is located over the entire circumference of the cross section of the rim portion 15 (FIG. 16). Moreover, although the thickness of the outer side covering part 23 is adjusted with temperature rising property, tactile sense, moldability, etc., it is preferable to set it as 2 mm or less, for example.

  In this way, the heater wire 21 is held by the holding member 71 on the inner covering portion molding die 31 and installed, and is integrally molded (insert molding) with the inner covering portion 20, thereby forming the heater wire 21 into the inner covering portion. The workability when installing on the mold 31 is good, and the heater wire 21 can be reliably fixed to the inner covering portion 20 with fewer man-hours.

  In addition, since the heater wire 21 is installed in the inner covering portion molding die 31 along the flow direction of the resin raw material 35, the heater wire 21 hardly obstructs the flow of the resin raw material 35 filled in the cavity 36, and voids (air The occurrence of recesses such as holes) can be suppressed.

  Furthermore, since the heater wire 21 is held by the holding member 71, the arrangement of the heater wire 21 can be arbitrarily selected. In particular, in the present embodiment, since the heater wire 21 can be arranged also on the inner peripheral side of the rim portion 15, the fingertip of the occupant (driver) holding the rim portion 15 can be effectively warmed by the heater wire 21. .

  Moreover, since the heater wire 21 is installed in each of the first first half mold 33 and the first other half mold 34 of the inner covering portion forming die 31, the inner covering portion 20 is formed, so that the core metal 15a is formed. Regardless of the shape, the entire rim portion 15 of the steering wheel 10 can be warmed from the front side to the back side.

  In the fifth embodiment, as in the sixth embodiment shown in FIG. 17, for example, the flow of the resin raw material 35 on the opposite side to the first gate 38 of the inner covering portion molding die 31. A holding member forming space for forming the holding member 71 is connected to an end, that is, an upper portion, in other words, an overflow portion 78 that is provided at the 12 o'clock position of the analog timepiece and receives the resin material 35 overflowed from the cavity 36. A configuration may be employed in which a certain holding member forming cavity 79 is provided. In this case, when the inner covering portion 20 is molded, the resin raw material 35 filled in the cavity 36 overflows from the cavity 36 to the overflow portion 78 and is filled into the holding member forming cavity 79. At the same time, the holding member 71 can be formed. That is, a so-called family mold (simultaneous shape simultaneous molding) is performed in which a portion of the inner covering portion forming die 31 that does not become the inner covering portion 20 is simultaneously formed with a holding member 71 having a shape different from that of the inner covering portion 20. be able to. The molded holding member 71 can be used when the inner covering portion 20 of the steering wheel 10 is molded next time.

  In the sixth embodiment, the holding member molding cavity 79 may be provided in the overflow portion of the outer covering portion molding die.

  Further, in the fifth and sixth embodiments described above, as in the seventh embodiment shown in FIG. 18, the holding member main body 73 of the holding member 71 is replaced with a locking portion instead of the locking projection 74. And the holding member 71 may be held by using a daruma pin 82 as a holding means movably provided in the inner covering portion forming die 31. The daruma pin 82 is provided on the first first molding surface 33a of the first first half mold 33 and the first other molding surface 34a of the first other half mold 34 so as to be able to advance and retract. The distal end portion is provided with a spherical locking pin portion 82a having an outer shape (outer diameter) larger than the inner shape (inner diameter) of the locking hole portion 81. In the heater wire installation step, the daruma pin 82 is inserted from the first first molding surface 33a of the first first half mold 33 and the first other molding surface 34a of the first other half mold 34. The heater wires 21 are installed on the first first molding surface 33a and the first other molding surface 34a, respectively, and the holding member main body 73 of each holding member 71 is placed on the heater wire 21. The retaining pin portion 82a of the daruma pin 82 is press-fitted into the retaining hole portion 81 while covering the first and second molding surfaces 33a and 34a and the holding member body 73. Thus, the heater wire 21 is held (FIG. 18A). At this time, since the holding member 71 has elasticity, the locking pin portion 82a of the daruma pin 82 is pressed into the locking hole portion 81 while elastically deforming the locking hole portion 81, and the holding member 71 is securely held. To do. Then, after the inner covering portion 20 is formed, when the intermediate body M1 is removed from the inner covering portion forming die 31, the daruma pin 82 is connected to the first first forming surface 33a and the first other forming surface 34a. The locking pin portion 82a is removed from the locking hole portion 81 (FIG. 18B). With this configuration, as in the fifth and sixth embodiments described above, post-processing such as cutting off the locking projections 74 is not necessary, and the manufacturability is further improved. It is difficult to hinder the flow, and the resin material 35 can be filled smoothly into the cavity 36.

  Further, in the fifth to seventh embodiments, as in the eighth embodiment shown in FIGS. 19 and 20, instead of the heater wire 21, a heating element 84 in which heating wires are formed in a net shape is provided. It may be used. In this case, for example, a plurality of projecting portions 85 as support portions narrower than the mesh of the heating element 84 are provided on the first first molding surface 33a and the first other molding surface 34a. Is inserted into the mesh of the heating element 84 pre-shaped into a semi-cylindrical surface along the first first molding surface 33a and the first other molding surface 34a, thereby supporting the heating element 84. By installing the heating element 84 on the first first molding surface 33a and the first other molding surface 34a, the same operational effects as those of the fifth to seventh embodiments can be obtained.

  In the fifth to eighth embodiments, the heater wire 21 or the heating element 84 may be installed only in the first first half mold 33, or only in the first other half mold 34. You may install in. That is, the heater wire 21 or the heating element 84 can be installed in at least one of the first first half mold 33 and the first other half mold 34.

  Next, a ninth embodiment will be described with reference to FIGS. In addition, about the structure and effect | action similar to said each embodiment, the same code | symbol is attached | subjected and the description is abbreviate | omitted.

  In the steering wheel 10 according to the ninth embodiment, the inner covering portion 20 includes a core layer 86 that covers the core metal 15a and a surface layer 87 that covers the core layer 86.

  In the present embodiment, the core layer 86 and the surface layer 87 are formed of the same material, for example, a fine foamed polyurethane resin.

  The core layer 86 is different in thickness on one side, for example, the outer peripheral side 86a, and on the opposite side, that is, on the other side, for example, the inner peripheral side 86b. The thickness T1 of the outer peripheral side 86a is the same as that of the inner peripheral side 86b. It is set larger than the thickness T2. That is, the core layer 86 has a cross-sectional shape in which a semicircular outer peripheral side 86a having a relatively large diameter dimension and a semicircular inner peripheral side 86b having a relatively small diameter dimension continue in a step shape. doing. Then, in a state where the core layer 86 is covered, the surface layer 87 has a shape with no step between, for example, the outer peripheral side 87a which is one side on the surface and the inner peripheral side 87b which is the other side. That is, the surface layer 87 has a relatively small thickness T3 on the outer peripheral side 87a (for example, 0.5 to 1.5 mm (0.5 mm to 1.5 mm), preferably about 1.0 mm), The thickness T4 is set to be relatively large so that the thickness difference between the outer peripheral side 86a and the inner peripheral side 86b of the core layer 86 is offset.

  The steering wheel 10 according to the present embodiment includes a core layer forming die 88, an inner covering portion forming die 31 as a surface portion forming die, and an outer covering portion forming die. To be molded.

  The core layer mold 88 includes a third half mold 91 and a third other half mold 92. The third half mold 91 and the third other half mold 92 are A cross-section filled with a resin raw material 93 which is a liquid surface layer resin raw material which is a reaction mixed liquid (for example, a liquid obtained by mixing an isocyanate and a polyol (and an antioxidant, a colorant, etc.)). A (third) cavity 94, which is a circular (third) space in a circular shape when viewed from the front, is formed. In other words, the third first half mold 91 facing the third other half mold 92 is provided with a third cylindrical mold-shaped third molding surface 91a. In the third other half mold 92 that is opposed, for example, a third other molding surface 92a having a semi-cylindrical surface shape having a diameter smaller than that of the third first molding surface 91a is formed. In the present embodiment, the third first half mold 91 is the front side (rear side) that is the occupant side of the rim portion 15, and the third other half mold 92 is the rear side that is the occupant side of the rim portion 15 ( This is the front side. Further, the core layer molding die 88 is for mixing a resin raw material 93 with a third mixing head (not shown) for mixing and stirring and discharging the resin raw material 93 and a resin raw material 93 discharged from the third mixing head. A third after-mixer (not shown), and a third gate (not shown) into which the resin raw material 93 mixed by the third after-mixer is injected into the cavity 94 is, for example, the third half mold 91 of the third half mold 91. 3 is formed continuously on one molding surface 91a. Note that the third mixing head, the third aftermixer, and the third gate are the same as the first mixing head, the first aftermixer 37, and the first gate 38, and thus the description thereof is omitted. To do. In the third embodiment, since the resin raw material 93 used for the core layer 86 and the surface layer 87 is the same in the third mixing head and the third aftermixer, the first mixing head and the first aftermixer are used. The raw material may be supplied from the RIM machine that is common to the RIM machine that supplies the raw material to the after mixer 37.

  In this embodiment, the inner covering portion molding die 31 has a first first half die 33 positioned on the outer peripheral side of the rim portion 15 and a first other half die 34 located within the rim portion 15. It is configured to be located on the circumferential side.

  When the steering wheel 10 is manufactured, first, an intermediate body M2 in which the core layer 86 covering the cored bar 15a is formed is formed using the core layer forming die 88. At this time, the metal cores 15a and 17a integrated with the boss plate 19 and the like are installed in the third first mold half 91 (core metal installation process). A cavity 94 is formed by mold matching with the half mold 92 (mold closing), and the resin raw material 93 discharged from the third mixing head is agitated and mixed by the resin flow path of the third aftermixer to form the third gate. The resin raw material 93 reacts in the cavity 94 to become polyurethane and the core layer 86 is formed (core layer forming step (FIGS. 21A and 22A). )). In this state, the core layer 86 is formed in a shape in which the thickness T2 of the inner peripheral side 86b is smaller than the thickness T1 of the outer peripheral side 86a.

  Next, the pre-shaped heater wire 21 is placed on the first first molding surface 33a of the inner covering portion molding die 31 (heater wire placement step which is a heating element placement step). At this time, the heater wire 21 can be installed by any installation method similar to each of the above-described embodiments, but for example, it is arranged in a wavy shape that is alternately folded in a direction intersecting the circumferential direction of the rim portion 15, It is curved into a semi-cylindrical surface along the first first molding surface 33a. Further, the surface of the core layer 86 of the intermediate body M2 removed from the core layer mold 88 is subjected to a treatment for improving the adhesion with the surface layer 87, and this intermediate body M2 is applied to the inner covering portion molding mold 31. While being installed, the first one half mold 33 and the first other half mold 34 are matched (mold closed) to form a cavity 36. At this time, since the thickness T2 of the inner peripheral side 86b opposite to the side where the heater wire 21 of the core layer 86 is located is smaller than the thickness T1 of the outer peripheral side 86a where the heater wire 21 is located, the inner peripheral side 86b Is disposed farther from the outer peripheral side 86a than the cavity 36 (first other molding surface 34a) of the inner covering portion molding die 31, and the inner peripheral side 86b of the core layer 86 and the inner covering portion molding. A flow path 96 continuous in the circumferential direction is formed between the cavity 36 (first other molding surface 34a) of the mold 31, and other portions, mainly the outer peripheral side 86a of the core layer 86 and the inner covering portion. A narrow channel 97 that is continuous in the circumferential direction and narrower than the channel 96 is formed between the cavity 36 (first first molding surface 33 a) of the molding die 31. Then, the resin raw material 93 which is the core layer resin raw material discharged from the first mixing head is stirred and mixed by the first after-mixer 37 and filled into the cavity 36 through the first gate 38. The resin raw material 93 has a high flow velocity in the flow path 96 and quickly reaches the flow end, that is, reaches the 12 o'clock position of the analog timepiece corresponding to the upper side of the rim portion 15. On the other hand, the resin material 93 has a relatively large flow resistance in the narrow channel 97 and flows slowly. For this reason, the filling of the resin raw material 93 proceeds from the channel 96 side to the narrow channel 97 side, that is, the heater wire 21 side. At this time, since the flow of the resin raw material 93 is slow, the heater wire 21 installed in the cavity 36 of the inner covering portion forming die 31 is confined in the resin raw material 93 while maintaining the pattern as it is. Further, the resin raw material 93 flowing through the narrow channel 97 has a short flow distance because the resin raw material 93 already spread in the channel 96 is supplied from the channel 96 side, and flows simultaneously with the channel 96. In addition, there is no short shot problem due to confining air in the narrow channel 97. That is, the flow path 96 in the vicinity of the first gate 38 generates a flow of the resin raw material 93 in the vertical direction toward the upper side, and at the same time, the flow of the resin raw material 93 to the narrow flow path 97 opposite to the flow path 96. Since a flow is generated, the surface layer 87 is grown upward in this portion while filling in the horizontal direction from the flow channel 96 side. Accordingly, the resin raw material 93 filled in the cavity 94 in this way reacts in the cavity 94 to become polyurethane, so that the surface layer 87 is formed to cover the entire core layer 86, and the inner covering portion 20 is completed ( Surface layer forming step (FIG. 21 (b) and FIG. 22 (b)).

  Thereafter, the removed intermediate M1 is inserted into the outer cover mold, and the outer cover 23 is formed in the same manner as in each of the above embodiments, and the second half mold and the second other mold are formed. The half mold is opened and the steering wheel 10 is removed.

  In this way, the heater wire 21 is integrally formed (insert molding) with the inner covering portion 20 on the surface layer 87, so that, for example, the heater wire is sewn or bonded to the surface of the inner covering portion. Thus, the workability is good and the man-hours can be reduced, the steering wheel 10 provided with the heater wire 21 on the rim portion 15 can be manufactured at a lower cost, the heater wire 21 is less likely to lose its shape, and the heater wire 21 can be used for a long time. The shape can be reliably maintained over the entire range.

  Further, the foamed urethane constituting the surface layer 87 has a shape in which the resin raw material 93 expands and forms due to foaming. Therefore, the resin raw material 93 needs to flow uniformly into the cavity 94 in advance. In particular, when the surface layer 87 is formed to be thin, it is important to uniformly flow the resin raw material 93 into the cavity 94 before foaming. On the other hand, if it is forced to flow, there is a risk of roughing or lacking after molding. Therefore, in the present embodiment, the core layer 86 having a relatively small thickness T2 on the inner peripheral side 86b with respect to the thickness T1 on the outer peripheral side 86a is formed, and the intermediate body M2 including the core layer 86 is formed as a core layer. A wider flow path 96 is formed between the inner peripheral side 86b of 86 and the inner cover part forming die 31 than between the outer peripheral side 86a of the core layer 86 and the inner cover part forming die 31 (narrow flow path 97). Thus, the resin raw material 93 can be effectively and uniformly poured into the cavity 94 using the flow path 96. Therefore, the surface layer 87, and thus the rim portion 15, can be reliably molded with a good appearance without causing a lack of thickness.

  In addition, by forming the core layer 86 and the surface layer 87 from the same synthetic resin, a sense of incongruity when the rim portion 15 is gripped due to the thickness at the position of the flow path 96 is less likely to occur.

  As a result, the steering wheel 10 provided with the heater wire 21 on the rim portion 15 having a soft feel can be manufactured at a lower cost without making the inner covering portion 20 and the outer covering portion 23 unnecessarily thick. The outer covering portion 23 does not lower the temperature rise performance of the rim portion 15 by the heater wire 21.

  Next, a tenth embodiment will be described with reference to FIGS. In addition, about the structure and effect | action similar to said each embodiment, the same code | symbol is attached | subjected and the description is abbreviate | omitted.

  In the manufacturing method of the steering wheel 10 of the tenth embodiment, the heater wire 21 is fixed to the surface 101a of the sheet-like film 101 which is a carrier (carrier material), and the inner covering portion 20 is used by using the film 101. The heater wire 21 is transferred to the surface.

  The film 101 is formed of, for example, a member such as a synthetic resin, and preferably, a PET film having a thickness of 38 μm or less, or a flexible vinyl chloride or elastomer film is used. The film 101 is formed in, for example, an annular shape corresponding to the shape of the rim portion 15 of the steering wheel 10. Furthermore, this film 101 has slight adhesiveness only on the surface 101a.

  Then, the heater wire 21 is fixed to the surface 101a of the film 101 by the mounting device 103 shown in FIG. 24 in a predetermined pattern, in this embodiment, a pattern that is alternately folded back in the direction intersecting the circumferential direction. The

  The mounting device 103 includes, for example, an annular pedestal portion 103a corresponding to the shape of the film 101, and a plurality of hook pins 103b which are a plurality of hook members standing upright with respect to the pedestal portion 103a.

  The pedestal portion 103a is formed in a plate shape from a metal such as an iron plate, for example.

  The hook pin 103b may be formed of a member such as a synthetic resin, for example, and may be subjected to fluororesin processing or the like so that glue or an adhesive is difficult to adhere to the surface. For example, two sets that are spaced apart in the radial direction of the pedestal portion 103a are set as one set, and a plurality of sets are arranged at substantially equal intervals in the circumferential direction of the pedestal portion 103a. The hook pin 103b is disposed through the pedestal portion 103a throughout the pedestal portion 103a. However, for the sake of clarity, only a part of the hook pin 103b is shown in FIG. The hook pin 103b is omitted.

  First, the surface of the heater wire 21 is pre-coated with, for example, a hot-melt adhesive that softens with heat and has an adhesive effect, and the heater wire 21 is placed on one main surface of the pedestal 103a. Hang so as to meander between the hook pins 103b. Next, the heater wire 21 is moved together with the pedestal 103a to the surface 101a of the film 101, and the heater wire 21 is fixed to the surface 101a of the film 101 by the adhesiveness of the surface 101a. After fixing the heater wire 21, the pedestal 103a is separated from the film 101, and only the heater wire 21 remains on the surface 101a of the film 101 (heating element applying step).

  In this way, the film 101 with the heater wire 21 applied to the surface 101a is formed by placing the core bars 15a and 17a integrated with the boss plate 19 and the like inside the cavity 36 of the inner covering portion molding die 31. Wrapped around the surface of the inner covering portion 20 formed in advance (winding step (FIG. 23 (a))). Is heated for about 5 minutes (heating step (FIG. 23 (b))), the adhesive coated on the surface of the heater wire 21 is melted and adhered to the surface of the inner covering portion 20. The adhesion of the heater wire 21 to the inner covering portion 20 by the adhesive is stronger than the slight adhesiveness of the surface 101a of the film 101, and therefore, only the film 101 is peeled off and the heater wire 21 becomes the inner covering portion 20. It is transferred to the surface of the substrate (peel removal step (FIG. 23C)). That is, a transfer process for transferring the heater wire 21 to the surface of the inner covering portion 20 is configured by the winding process, the heating process, and the peeling removal process. As a result, the intermediate body M1 in which the heater wire 21 is provided on the surface of the inner covering portion 20 is manufactured.

  Thereafter, similarly to the first embodiment, the outer covering portion 23 is formed so as to cover the entire surface of the inner covering portion 20 using the outer covering portion forming die (FIG. 23 (d)). The steering wheel 10 is removed from the mold by opening the second first half mold and the second other half mold.

  In this way, by transferring the heater wire 21 fixed to the surface 101a of the film 101 to the surface of the inner covering portion 20, for example, even when the heater wire 21 is divided into a plurality of systems, the film 101 is used once. The heater wire 21 can be easily and securely fixed to the inner cover portion 20 with less man-hours, and the steering wheel 10 provided with the heater wire 21 on the rim portion 15 can be cheaper. Compared to the case where the heater wire is fixed to the surface of the inner covering portion with, for example, double-sided tape, the heater wire 21 is less likely to lose its shape, and the heater wire 21 can be shaped more reliably over a long period of time. .

  In addition, since the heater wire 21 can be fixed to the surface of the inner covering portion 20 without using a separate sheet or the like, a separate sheet or the like is unnecessary, and the inner covering portion 20 caused by the wrinkles or the like of this separate sheet. The surface unevenness of the outer covering portion 23 (rim portion 15) does not occur.

  Furthermore, since the heater wire 21 can be fixed to the surface 101a of the film 101 using the mounting device 103, from the fixing of the surface 101a of the film 101 of the heater wire 21, winding around the surface of the inner covering portion 20 of the film 101, heating In addition, the efficiency of fixing the heater wire 21 to the surface of the inner covering portion 20 leading to the peeling of the film 101 can be greatly improved, and semi-automation can be achieved.

  In the tenth embodiment, the film 101 may be configured to be flexible by providing a slit.

  Further, the arrangement of the hook pins 103b can be changed as appropriate according to the required arrangement pattern of the heater wires 21.

  Furthermore, the heater wire 21 may be transferred to the surface of the surface layer 87 of the ninth embodiment by using the film 101 of the tenth embodiment.

  In each of the above embodiments, the outer covering portion 23 is formed by, for example, winding a sheet-like skin body such as leather, synthetic leather, or synthetic resin around the surface of the inner covering portion 20 and fixing it by sewing or the like. You can also In this case, a steering wheel with a heating element similar to a general so-called leather-wrapped steering wheel can be obtained.

  Further, the inner covering portion 20 can be formed into an arbitrary multilayer.

  In addition, the steering wheel 10 is not limited to the configuration including the three spoke portions 17, and can be applied to a configuration including, for example, the four spoke portions 17.

  In place of the airbag device 12, for example, a pad body that houses an impact absorber can be used.

  The present invention can be suitably used, for example, as a steering wheel for an automobile.

10 Steering wheel that is a steering wheel
15 Rim as grip
15a cored bar
20 Covering part as planned gripping part
21 Heater wire as a heating element
22 Fabric material
23 Outer covering as skin
31 Mold for inner coating part, which is a mold for planned part as surface mold
35 Resin raw material
84 Heating element
86 Core layer
86a Outer side, one side
86b Inner side, which is the other side
87 Surface
88 Mold for core layer
93 Resin raw materials that are resin materials for core layers and resin materials for surface layers
96 channels
101 Film as carrier M2 Intermediate

Claims (4)

A method of manufacturing a handle for manufacturing a handle provided in a gripping part that grips a heating element that generates heat when energized,
A scheduled part molding step of molding a planned gripping part in which the heating element and the cored bar are filled with a liquid resin raw material into a molding die for a planned part, and the heating element is integrally fixed to the surface part;
A method of manufacturing a handle, comprising: forming a skin portion by covering the planned grip portion including the heating element to form the skin portion. The planned part molding process is
A cloth material installation process in which a cloth material in which a heating element is integrally fixed to the surface is installed in a molding die for a planned portion;
A cored bar installation step of installing a cored bar in the mold for the planned part;
2. A molding step of filling a liquid resin raw material into the molding part mold in which the heating element and the cored bar are respectively installed, and molding the planned gripping part. A method for manufacturing a handle. The gripping portion is composed of a core layer that has a smaller thickness on the other side than the one side and covers at least a part of the cored bar, and a surface layer that covers the core layer,
The planned part molding process is
A core layer molding step of molding the core layer by covering at least a part of the core metal by filling a liquid core layer resin raw material in the core layer molding die in which the core metal is installed;
A heating element installation step of installing a heating element in the surface layer mold,
An intermediate body including a core layer covering at least a part of the core metal in the surface layer mold, one side of the core layer and the surface layer between the other side of the core layer and the surface layer mold An intermediate installation process for installing a flow path wider than that between the mold for molding,
The surface layer molding step of forming the surface layer by filling a liquid surface layer resin raw material into the surface layer molding die using the flow path is provided. Production method. A method of manufacturing a handle for manufacturing a handle provided in a gripping part that grips a heating element that generates heat when energized,
A planned part molding step for molding a planned grip part by filling a liquid resin raw material in a mold for a planned part in which a core metal is installed;
A transfer step of winding the carrier holding the heating element around the surface of the gripping portion and transferring the heating element to the surface of the gripping portion;
A method of manufacturing a handle, comprising: forming a skin portion by covering the planned grip portion including the heating element to form the skin portion.

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