Vehicle steering wheel device

Abstract

This vehicle steering wheel device comprises a housing 9 which holds an air bag cushion, a locking plate 8 which is provided on a rear surface 9d of the housing such that plate surfaces thereof overlap, and which has a damper unit assembled thereto, a coil spring which resiliently supports the locking plate, that overlaps the housing, on a steering wheel, and a bush 25 provided inserted through both the housing and the locking plate in order to fix the coil spring, wherein: the bush is locked and fixed to the locking plate using a first locking means; and the bush, fixed to the locking plate using the first locking means, is locked and fixed to the housing using a second locking means.

Description

[Technical Field]

[0001] The present invention relates to a vehicle steering wheel device that can improve the durability of the mounting and fixing points of coil springs when accessory members or accessory parts are attached to the vehicle steering wheel in an elastically supported state via coil springs. [Background technology]

[0002] 2. Description of the Related Art There are various known structures for attaching various accessory members and accessories, such as an airbag module and a horn circuit, to a steering wheel of a vehicle via a coil spring in a resiliently supported state.

[0003] In the "Damper Unit for Airbag Module and Steering Wheel" of Patent Document 1, the steering wheel includes a steering wheel body and an airbag module attached to the steering wheel body via a horn plate and multiple damper units. The damper unit includes a protector, a rubber bushing, and a resin bushing. A coil spring is interposed between the leg piece and the core of the protector in a force-storing state.

[0004] In the "steering wheel" of Patent Document 2, the tip of a pin protruding from the airbag module passes through a cylindrical guide member provided on the horn plate and projects out the back surface of the horn plate. A tapered surface is provided on the tip of the pin, and a lock spring provided on the back surface of the horn plate presses against the tapered surface. The airbag module is pressed against a rubber mount provided on the base portion of the horn plate, compressing the mount seat portion. The distance between the horn switch and the rubber mount is 15 mm or less. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Application Laid-Open No. 2017-159696 [Patent Document 2] Japanese Patent Application Publication No. 2019-006341 Summary of the Invention [Problem to be solved by the invention]

[0006] The steering wheel is a transmission path for vibrations from the road surface, etc. This means that vibrations are input to the various accessories and components attached to the steering wheel, and also to the coil springs interposed between the steering wheel and these accessories, which can result in play in the attachment and fixing points of the coil springs. Therefore, measures to improve the durability of these attachment and fixing points have been desired.

[0007] The present invention was devised in consideration of the above-mentioned conventional problems, and aims to provide a vehicle steering wheel device that can improve the durability of the mounting and fixing points of the coil spring when ancillary members or components are attached to the vehicle steering wheel in an elastically supported state via the coil spring. [Means for solving the problem]

[0008] A vehicle steering wheel device according to one aspect of the present invention comprises a holding plate that holds accessories to a steering wheel of a vehicle, an assembly plate that is arranged with its plate surface overlapping the plate surface of the holding plate and to which accessories to the steering wheel are attached, a coil spring that elastically supports the assembly plate that has been overlapped with the holding plate to the steering wheel, and a bush that is inserted through both the holding plate and the assembly plate to secure the coil spring, wherein the bush is locked and fixed to the assembly plate by a first locking means, and the bush fixed to the assembly plate by the first locking means is locked and fixed to the holding plate by a second locking means.

[0009] It is desirable that the first locking means include: a first through hole formed in the assembly plate material, through which the bushing is inserted so as to be rotatable around the bushing; a plurality of hooks formed on the bushing at intervals around the bushing so as to be elastically bendable; a pressing flange portion formed in the first through hole toward the inside of the first through hole, which elastically bends and deforms the hooks moved by rotation of the bushing; a pair of engaging portions formed on the bushing, which engage with the pressing flange portion from both the front and back sides as the bushing rotates, thereby supporting the bushing on the assembly plate material; and a groove portion formed in the pressing flange portion, which elastically restores the hooks moved by rotation of the bushing and engages the hooks to prevent rotation of the bushing.

[0010] The second locking means preferably includes a second through hole formed in the holding plate and through which the bush, which is locked and fixed to the assembly plate by the first locking means, is inserted, and a stopper protrusion formed on the bush facing outward from the bush, and the second through hole preferably has a locking flange formed inward from the second through hole and for locking the stopper protrusion to prevent rotation of the bush. [Effects of the Invention]

[0011] In the vehicle steering wheel device of the present invention, when ancillary members or components are attached to the vehicle steering wheel in an elastically supported state via a coil spring, the durability of the attachment and fixing portion of the coil spring can be improved. [Brief explanation of the drawings]

[0012] [Figure 1] 1 is a perspective view illustrating an example of an outline of a steering wheel to which a vehicle steering wheel device according to an embodiment of the present invention is applied; [Figure 2] FIG. 2 is a side cross-sectional view of the steering wheel of FIG. 1. [Figure 3]2 is an exploded perspective view showing an example of an airbag module provided in the steering wheel of FIG. 1. FIG. [Figure 4] FIG. 4 is a perspective view of the airbag module shown in FIG. 3 as seen from the back side. [Figure 5] 1 is an explanatory view of a housing applied to a vehicle steering wheel device according to an embodiment of the present invention. [Figure 6] 3 is an explanatory diagram of a locking plate applied to the vehicle steering wheel device according to the embodiment of the present invention. FIG. [Figure 7] FIG. 7 is an explanatory diagram showing an outline of how a coil spring is attached to the locking plate shown in FIG. 6 via a bush. [Figure 8] 1 is an explanatory diagram of a bushing applied to a vehicle steering wheel device according to an embodiment of the present invention. [Figure 9] 5 is an explanatory diagram illustrating attachment of a bush to a locking plate in a vehicle steering wheel device according to an embodiment of the present invention. FIG. [Figure 10] 5 is an explanatory diagram illustrating attachment of a bush to a housing in a vehicle steering wheel device according to an embodiment of the present invention. FIG. [Figure 11] This is an expanded cross-sectional view of region P in FIG. 10(c). DETAILED DESCRIPTION OF THE INVENTION

[0013] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A preferred embodiment of a vehicle steering wheel device according to the present invention will be described in detail below with reference to the accompanying drawings.

[0014] 1 to 6 show a steering wheel 1 for a vehicle and an airbag module 2 attached to the steering wheel.

[0015] FIG. 1 is a perspective view illustrating an outline of a steering wheel 1 to which an airbag module 2 is attached, and FIG. 2 is a side cross-sectional view thereof.

[0016] In the following drawings including FIG. 1, it is assumed that the steering position of a steering wheel 1 attached to a vehicle is in a neutral position, and each direction is illustrated as an example.

[0017] The neutral steering position refers to a position where the steering angle of the steering wheel 1 is "zero" and the steered front wheels are facing in a straight ahead direction.

[0018] In the drawing, the Z axis of the three-dimensional coordinate system (hereinafter sometimes referred to as the "Z axis direction") is an axis parallel to the rotation axis of the steering shaft (not shown). The Z axis is oriented along the steering shaft, with the front wheels pointing downward and the steering wheel 1 pointing upward. In terms of its relationship with other members, the Z axis direction is parallel to the axis of the coil spring 24 (described later). The Z axis direction is also parallel to the direction in which the housing 9, which serves as a holding plate, and the locking plate 8, which serves as an assembly plate, are overlapped.

[0019] Similarly, the direction of the X axis of the three-dimensional coordinate system is from 3 o'clock (right) to 9 o'clock (left) on an analog clock in a plane perpendicular to the Z axis, and the direction of the Y axis is from 12 o'clock (up) to 6 o'clock (down) on the same plane. In addition, the side seen from the driver's side is referred to as the front side, and the opposite side is referred to as the back side.

[0020] The steering wheel 1 is installed at the driver's seat of the vehicle, is connected to a steering shaft, and transmits the steering operation by the driver to a steering gear and the like.

[0021] An airbag module 2 that functions as a driver's seat airbag in an emergency is provided in the center of the steering wheel 1.

[0022] The airbag module 2 also functions as a horn switch that is pressed by the driver to sound the horn under normal circumstances.

[0023] The airbag module 2 also functions as a module damper that attenuates vibrations of the steering wheel 1.

[0024] The steering wheel 1 is made of metal and is roughly composed of a central boss portion 3, a rim 4 that is gripped by the driver, and spokes 5 that connect the boss portion 3 and the rim 4. A steering shaft is connected to the boss portion 3.

[0025] To explain the structure of the airbag module 2, the driver's side of the airbag module 2 is covered with a resin horn cover 6 that functions as a design surface.

[0026] An airbag cushion 7 that is deployed and inflated in an emergency is stored in a folded state inside the horn cover 6.

[0027] As shown in FIG. 3 , the airbag module 2 is composed of a metal locking plate 8, a metal housing 9 formed in a dish shape with a peripheral wall 9a on the surface side and with its plate surface overlapping the plate surface of the locking plate 8, two hollow cylindrical damper units 10, a pin 11 slidably inserted into the hollow interior of the damper unit 10 and connecting the airbag module 2 to the boss portion 3 of the steering wheel 1, a connecting member 12 provided on the housing 9 and formed in the shape of a hook that engages with the boss portion 3 of the steering wheel 1 and connects the airbag module 2 to the boss portion 3 slidably in the Z-axis direction, an inflator 13 that supplies inflator gas to the airbag cushion 7, a metal retainer ring 15 having a bolt 15a to which a nut 14 is fastened and that fixes the airbag cushion 7, the inflator 13, etc. to the housing 9, and a horn cover 6 that houses the airbag cushion 7.

[0028] As will be described later, the damper unit 10 is an example of an accessory part to the steering wheel 1, and is assembled to a locking plate 8 serving as an assembly plate material.

[0029] Similarly, as will be described later, the airbag cushion 7 is an example of an accessory member to the steering wheel 1, and is held by a housing 9 serving as a holding plate member.

[0030] The damper unit 10 is a member that elastically mounts the airbag module 2 to the steering wheel 1, and forms the center of the module damper.

[0031] Briefly, the damper unit 10 is configured by housing a ring-shaped elastic body 16 that damps vibrations inside a holder 17, and by engaging an insulator plate 18 that is superimposed on one end of the elastic body 16 with a sleeve 19 that is inserted into and held within the elastic body 16.

[0032] The pin 11 provided in the damper unit 10 has a flange portion 11a at one end. The pin 11 is inserted into the damper unit 10 from the housing 9 side so that the flange portion 11a abuts against the sleeve 19 of the damper unit 10.

[0033] 4, the two damper units 10 are aligned in the X-axis direction with the neutral position of the steering wheel 1 as a reference, and are disposed close to both the left and right sides of the airbag module 2. In other words, when the steering angle of the steering wheel 1 is set to zero, the two damper units 10 are provided at positions corresponding to 3 o'clock and 9 o'clock on an analog clock relative to the central axis (steering shaft) of the steering wheel 1.

[0034] The pin 11 is provided so as to protrude from the damper unit 10 toward the boss portion 3 of the steering wheel 1 in the Z-axis direction.

[0035] The housing 9 and the locking plate 8 will be described with reference to FIGS. 3, 5(a) and 6(a).

[0036] FIG. 5(a) is a perspective view of the housing 9 as seen from the rear side, and FIG. 6(a) is a perspective view of the locking plate 8 as seen from the rear side.

[0037] The locking plate 8 has a hole 8a formed through the center for mounting an inflator, and two groove-shaped retaining portions 20 formed at positions away from the hole 8a to match the arrangement of the two damper units 10.

[0038] The holding portion 20 has a locking hole 20a formed therethrough for locking and fixing the holder 17 of the damper unit 10 therein.

[0039] As a structure for fixing the damper unit 10 to the locking hole 20a, for example, the locking hole 20a and the holder 17 are both formed in an elliptical shape defined by a major axis and a minor axis, and the holder 17 is inserted into the locking hole 20a by aligning the major axes and the minor axes of the locking hole 20a and the holder 17, and then rotating the holder 17 to lock the holder 17 into the locking hole 20a. In this way, the damper unit 10 is assembled to the locking plate 8.

[0040] The pin 11 inserted into the damper unit 10 has a pointed portion 11b at the other end opposite to the flange portion 11a protruding from the locking hole 20a toward the boss portion 3 of the steering wheel 1 (see FIG. 4).

[0041] The housing 9 is formed in a size that covers almost the entire locking plate 8 including the holding portion 20 .

[0042] The housing 9 has a hole 9b formed in the center thereof for passing the inflator 13 therethrough, and a peripheral wall 9a formed at the outer edge thereof, rising up toward the front side.

[0043] The housing 9 covers the retaining portion 20, and the flange portion 11a of the pin 11 inserted into the damper unit 10 is sandwiched between the housing 9 and the retaining portion 20 of the locking plate 8, thereby causing the pin 11 and damper unit 10 to be incorporated and held between the housing 9 and the locking plate 8.

[0044] The locking plate 8 is formed with an assembly protrusion 8b so that the plate surfaces can be overlapped and assembled to the housing 9, and the housing 9 is formed with a locking hole 9c that fits with the assembly protrusion 8b.

[0045] Further, an elastically deformable locking piece 6b formed on the cylindrical portion 6a of the horn cover 6 of the airbag module 2 is locked in the locking hole 9c of the housing 9.

[0046] The horn cover 6 accommodating the airbag cushion 7 is attached to the housing 9 by the engagement of the engagement pieces 6 b with the engagement holes 9 c.

[0047] Furthermore, the housing 9 and the locking plate 8 are formed with bolt insertion holes 21 through which the bolts 15a of the retainer ring 15 are inserted.

[0048] The connecting member 12 provided on the housing 9 has, at one end along the Z-axis direction, a joining portion 12a joined to the peripheral wall 9a of the housing 9 with a rivet 22, and at the other end, a hook portion 12b that is engaged with the boss portion 3 of the steering wheel 1. The connecting member 12 is formed, for example, from an elastically deformable plate-like metal plate or the like.

[0049] The connecting member 12 is provided between the steering wheel 1 and the airbag module 2 in parallel with the damper unit 10.

[0050] The hook portion 12b is covered with a resin elastic material 23, which serves both as an electrical insulator between the boss portion 3 and the housing 9 and as a buffer.

[0051] The connecting member 12 has an opening 12c extending in the Z-axis direction between the joint portion 12a and the hook portion 12b. A protruding portion (not shown) of the boss portion 3 is inserted into the opening 12c. The airbag module 2 is slidable in the Z-axis direction relative to the boss portion 3 by the length of this opening 12c in the Z-axis direction.

[0052] As shown in FIG. 2, the pin 11 and the connecting member 12 are components that attach the airbag module 2 to the boss portion 3 of the steering wheel 1 in the Z-axis direction.

[0053] 4, the connecting member 12 is positioned downward in the vertical direction (Y-axis direction) of the steering wheel 1 with respect to the neutral position of the steering wheel 1. In other words, when the steering angle of the steering wheel 1 is set to zero, the connecting member 12 is located at a position corresponding to the 6 o'clock position of an analog clock relative to the central axis (steering shaft) of the steering wheel 1.

[0054] In terms of its positional relationship with the damper units 10, the connecting member 12 is disposed in the center between the two damper units 10 and closer to the lower side (6 o'clock side) than these damper units 10.

[0055] Therefore, the damper unit 10 and the connecting member 12 are disposed relative to the airbag module 2 at the vertices of an inverted isosceles triangle.

[0056] 4, the airbag module 2 is provided with a pair of coil springs 24 on both sides of the connecting member 12 along the X-axis direction via bushings 25. The axis of the coil spring 24 is parallel to the Z-axis direction. The axis of the coil spring 24 refers to a line (coil spring axis) that passes through the center of the coil spring 24.

[0057] More specifically, these coil springs 24 are disposed on the rear surface 8 c of the locking plate 8 and sandwiched between the boss portion 3 and the airbag module 2 .

[0058] The inflator 13 has a bolt insertion hole 21 and an outer peripheral flange 13 a that abuts against the back surface 8 c of the locking plate 8 .

[0059] Although not shown, an insertion hole for inserting the inflator 13 is formed in the airbag cushion 7. Bolt insertion holes for the retainer ring 15 are formed around the insertion hole.

[0060] The retainer ring 15 is provided inside the airbag cushion 7. The retainer ring 15 has a hole 15b that communicates with the hole 9b of the housing 9 and the hole 8a of the locking plate 8 and positions the inflator 13 inside the airbag cushion 7.

[0061] The retainer ring 15 is aligned with the insertion hole of the airbag cushion 7 so that the bolt 15a protrudes from the bolt insertion hole.

[0062] To assemble the airbag module 2, the housing 9 is aligned with the insertion hole 9b of the housing 9 and the bolt 15a of the retainer ring 15 protruding from the airbag cushion 7 is inserted into the bolt insertion hole 21 of the housing 9.

[0063] When the bolt 15 a is inserted into the bolt insertion hole 21 of the housing 9 , the periphery of the insertion hole of the airbag cushion 7 is sandwiched between the retainer ring 15 and the housing 9 , and the airbag cushion 7 is installed relative to the housing 9 .

[0064] As a result, the housing 9 holds the airbag cushion 7 which is an accessory member to the steering wheel 1.

[0065] On the other hand, for the locking plate 8, the damper unit 10 is mounted in the holding portion 20 from the front surface side (housing 9 side) of the locking plate 8, and is fixed to the locking plate 8 via the locking holes 20a.

[0066] The pin 11 has its pointed end 11b inserted into the damper unit 10 from the housing 9 side, and protrudes outward from the locking hole 20a of the locking plate 8.

[0067] Next, the housing 9 is placed over the locking plate 8 from the front side, and the two plates are stacked together. The stacking direction is parallel to the Z-axis direction.

[0068] The flange portion 11a of the pin 11 is sandwiched between the housing 9 and the locking plate 8 and is held therebetween.

[0069] Next, the outer peripheral flange 13a of the inflator 13 is abutted against the back surface 8c of the locking plate 8, and the inflator 13 is inserted into the insertion hole of the airbag cushion 7 through the hole 8a of the locking plate 8, the hole 9b of the housing 9, and the hole 15b of the retainer ring 15.

[0070] The bolts 15a of the retainer ring 15 protruding from the bolt insertion holes 21 of the housing 9 are inserted into the bolt insertion holes 21 of the locking plate 8 and the outer peripheral flange 13a of the inflator 13, and the nuts 14 are fastened from the back side of the locking plate 8.

[0071] As a result, the airbag cushion 7 and the inflator 13 are fixed and held in the housing 9, and a damper unit 10, which is an accessory part to the steering wheel 1, is attached to the locking plate 8.

[0072] The connecting member 12 attached to the housing 9 is disposed in parallel with the damper unit 10 along the Z-axis direction.

[0073] Next, the horn cover 6 is attached to the housing 9. The locking pieces 6b of the horn cover 6 are locked into the locking holes 9c of the housing 9.

[0074] In this manner, the airbag module 2 is assembled.

[0075] When the airbag module 2 is attached to the steering wheel 1 in the Z-axis direction, a coil-shaped horn spring 26, which is an elastic member that is elastically deformable, is provided between the boss portion 3 and the locking plate 8 to surround the pin 11, as shown in Figures 3 and 4. In addition, a pair of coil springs 24 are attached to bushings 25 on both sides of the connecting member 12.

[0076] The coil spring 24 and the horn spring 26 are brought into contact with the boss portion 3 to elastically support the airbag module 2 relative to the steering wheel 1.

[0077] The horn spring 26 ensures a gap between the boss portion 3 and the airbag module 2 for horn operation.

[0078] When the airbag module 2 is attached to the boss 3, the pin 11 is inserted and held at its tip 11b in an attachment hole (not shown) provided in the boss 3, with the coil spring 24 and the horn spring 26 elastically compressed. At the same time, the hook portion 12b of the connecting member 12 is engaged with the boss 3.

[0079] As a result, the airbag module 2 is attached to and connected to the steering wheel 1 in the Z-axis direction via the damper unit 10 and the connecting member 12.

[0080] Therefore, the airbag module 2 is connected to the steering wheel 1 via the damper unit 10 while being elastically supported by the horn spring 26 so as to be movable toward the steering wheel 1, i.e., capable of being pressed (see B in Figure 2).

[0081] The damper unit 10 is disposed between the airbag module 2 and the steering wheel 1 to damp vibrations of the steering wheel 1.

[0082] Vibrations of the steering wheel 1 are transmitted to the damper unit 10 via the pin 11. The transmitted vibrations are damped by the elastic body 16 of the damper unit 10, with the airbag module 2 acting as a damper mass.

[0083] In the event of an emergency, when a signal is sent from a sensor in the vehicle, inflator gas is supplied from inflator 13 to airbag cushion 7.

[0084] The airbag cushion 7 supplied with the inflator gas tears the horn cover 6 open, and deploys and inflates into the vehicle interior space to restrain the driver.

[0085] Regarding the horn function, when the airbag module 2 is pressed in the Z-axis direction toward the steering wheel 1, the entire airbag module 2 including the damper unit 10 slides against the pin 11 held in the boss portion 3, and the horn spring 26 is elastically compressed and deformed.

[0086] As a result, electrical continuity is established between the contacts provided on the airbag module 2 and the boss portion 3, causing the horn to sound.

[0087] When the pressure on the airbag module 2 is released, the horn spring 26 elastically restores its original shape, causing the airbag module 2 to move backward, which separates the contacts and stops the sound.

[0088] Therefore, the airbag module 2 and the steering wheel 1 form a conductive circuit.

[0089] The coil spring 24 is arranged on the back surface 8c of the locking plate 8 and sandwiched between the boss portion 3 and the airbag module 2, and elastically supports the airbag module 2 from the boss portion 3 side around the connecting member 12 arranged on the 6 o'clock side.

[0090] The coil spring 24 provides stable support for the airbag module 2 when the horn is not operated, and ensures good pressing operability of the airbag module 2 when the horn is operated.

[0091] Specifically, the coil spring 24 elastically supports the locking plate 8 on which the housing 9 is superimposed relative to the boss portion 3 .

[0092] The structure for attaching these coil springs 24 to the airbag module 2 side by means of bushings 25 will be described in detail with reference to FIGS.

[0093] FIG. 7 shows how the coil spring 24 is attached to the locking plate 8 via a bushing 25 .

[0094] FIG. 5(b) is an enlarged view of a main part of the housing 9, and FIG. 6(b) is an enlarged view of a main part of the locking plate 8. As shown in FIG.

[0095] 8(a) to 8(e) are a perspective view, a front view, a top view, a bottom view, and a side view of the bush 25, respectively.

[0096] Figure 9 is an explanatory diagram illustrating the attachment of bush 25 to locking plate 8, where Figure 9(a) is an oblique view showing how bush 25 is assembled to locking plate 8, Figure 9(b) is an explanatory diagram illustrating how bush 25 is locked by the first locking means, Figure 9(c) is an explanatory diagram illustrating the movement of bush 25 when locked by the first locking means, Figure 9(d) is an explanatory diagram illustrating how bush 25 is locked by the first locking means, and Figure 9(e) is an oblique view showing how bush 25 is fixed to locking plate 8.

[0097] Figure 10 is an explanatory diagram illustrating the attachment of bush 25 to housing 9, where Figure 10(a) is an oblique view showing how bush 25 is assembled to housing 9, Figure 10(b) is an explanatory view showing how bush 25 is locked by the second locking means, and Figure 10(c) is an oblique view showing how bush 25 is fixed to housing 9.

[0098] FIG. 11 is a developed cross-sectional view of region P in FIG. 10(c).

[0099] The bushing 25 is inserted through both the locking plate 8 and the housing 9 and fixes the coil spring 24 to the airbag module 2 .

[0100] The bushing 25 according to this embodiment is made of a synthetic resin material and has a substantially hollow cylindrical shape.

[0101] As shown in FIG. 8, the bushing 25 includes a spring holding portion 25a provided on one side (the boss portion 3 side) along the Z-axis direction and a fixing portion 25b provided on the other side (the airbag module 2 side).

[0102] One end of the coil spring 24 in the length direction is held by a spring holding portion 25a, and thereby the coil spring 24 is attached and fixed to the bushing 25 (see FIG. 7).

[0103] The bushing 25 is attached to the airbag module 2 by having the fixing portion 25b locked and fixed to the locking plate 8 by a first locking means and also locked and fixed to the housing 9 by a second locking means.

[0104] The double locking of the bush 25 means that the bush 25 alone is first locked to the locking plate 8 by a first locking means, and then the bush 25 attached to the locking plate 8 is locked together with the locking plate 8 to the housing 9 by a second locking means.

[0105] The first locking means and the second locking means may have any configuration as long as they can individually lock the bushing 25 to the locking plate 8 and the housing 9, respectively, and restrict or inhibit movement of the bushing 25.

[0106] In this embodiment, the first locking means is composed of a bushing 25 and a locking plate 8.

[0107] As shown in FIG. 6(b), the locking plate 8 is formed with a first through-hole 27 for inserting the bushing 25 therethrough so as to be rotatable around the bushing 25, that is, around the Z axis.

[0108] The first through-hole 27 is set to a size that allows the fixing portion 25b of the bushing 25 to be inserted therethrough.

[0109] As shown in FIG. 8, a plurality of hooks 29 are formed at intervals around the periphery of the bushing 25 in the fixing portion 25b of the bushing 25 so as to be elastically bendable and deformable.

[0110] In the illustrated example, two hooks 29 are formed at an interval of 180°. The hooks 29 are formed in an L-shape with a base end 29a connected to the bushing 25.

[0111] When the bushing 25 is inserted into the first through-hole 27, the hook 29 is positioned so that the L-shaped free end 29b faces the hole edge 27a of the first through-hole 27 (see FIG. 9(c)). The hook 29 is elastically bent and deformed toward the hollow interior of the bushing 25.

[0112] As shown in FIG. 6(b), the first through-hole 27 has a pressing flange 30 formed therein, which protrudes inward from the first through-hole 27.

[0113] That is, the size of the first through hole 27 is narrowed by the pressing flange portions 30. In the illustrated example, two pressing flange portions 30 are provided for two hooks 29.

[0114] When the bushing 25 is rotated as shown in FIG. 9(b), the pressing flange portion 30 causes the hook 29, which is moved along the hole edge 27a of the first through hole 27 by this rotation, to undergo elastic bending deformation as shown in FIG. 9(c).

[0115] The bushing 25 is formed with a pair of engaging portions that avoid the hooks 29 and engage with the pressure flange portion 30 from both the front and back sides.

[0116] Specifically, as shown in Figure 8, using the position of the free end 29b of the hook 29 as a reference, a first engagement portion 31 that engages with the back surface of the pressing flange portion 30 is formed on the side of the spring holding portion 25a in an arc-like shape and protrudes outward, and on the opposite side, a second engagement portion that engages with the surface of the pressing flange portion 30 is formed in the form of a protrusion and protrudes outward, positioned between the first engagement portions 31 and overlapping with the hook 29 with a gap in the Z-axis direction from the hook 29.

[0117] In this embodiment, the second engagement portion also serves as the stopper projection 32 (hereinafter, the second engagement portion will be referred to as the stopper projection).

[0118] In the illustrated example, two first engagement portions 31 and two stopper projections 32 are provided corresponding to the two pressure flange portions 30.

[0119] In the drawing, reference numeral 28 denotes a protrusion to which a jig for rotating and moving the bush 25 (see arrow R in FIG. 9(b)) is attached.

[0120] When the hook 29 is elastically deformed by the pressing flange 30 as the bush 25 rotates, the first engagement portion 31 and the stopper protrusion 32 engage with the pressing flange 30 from both the front and back sides, and are slid relative to the pressing flange 30 as the bush 25 rotates.

[0121] As shown in FIG. 6(b), the pressing flange 30 has a groove 33 formed by a partial cutout, into which the hook 29 fits.

[0122] As shown in FIG. 9(d), the groove portion 33 allows the hook 29, which is rotated in an elastically deformed state by the pressing flange portion 30 protruding inward of the first through-hole 27, to elastically restore its original shape.

[0123] Furthermore, the groove 33 locks the hook 29, which has elastically restored, in the circumferential direction of the first through-hole 27, thereby preventing the bush 25 from rotating.

[0124] When the hook 29 is locked in the groove 33, the bush 25 is supported on the locking plate 8 by the first engaging portion 31 and the stopper projection 32 which engage with the pressing flange 30 from both the front and back sides.

[0125] The hook 29 is engaged with the pressure flange portion 30 provided in the first through hole 27, and the bush 25 is locked and fixed to the locking plate 8 with the spring retaining portion 25a protruding from the locking plate 8 toward the boss portion 3, as shown in Figure 9(e), by the first locking means in which the paired first engagement portion 31 and stopper protrusion 32 engage.

[0126] The bushing 25 is attached to the rear surface 8c of the locking plate 8 as shown in FIG. 9(a).

[0127] When installing, the fixing portion 25b including the hook 29 and the stopper protrusion 32 is inserted into the first through hole 27 while avoiding the pressing flange portion 30, and then the bushing 25 is rotated to a position where the hook 29 is engaged with the groove portion 33.

[0128] In this embodiment, the second locking means is constituted by a stopper projection 32 formed on the fixing portion 25b of the bushing 25 and a second through hole 34 formed in the housing 9.

[0129] As described above, the stopper projection 32 also serves as the second engaging portion that engages with the pressing flange portion 30.

[0130] As shown in FIG. 5(b), the housing 9 is formed with a second through-hole 34 through which the bushing 25 is inserted.

[0131] The above-mentioned first through hole 27 is formed to a size that allows the stopper protrusion 32 to pass through, so that the stopper protrusion 32 can be positioned relative to the hole edge 34a of the second through hole 34 by inserting the bushing 25 from the back surface 8c side of the locking plate 6.

[0132] The second through hole 34 is set slightly larger than the first through hole 27 to provide some margin.

[0133] As shown in FIG. 5(b), a locking flange 35 is formed in the second through hole 34 so as to protrude inward of the second through hole 34.

[0134] As shown in Figure 10(b), when the bushing 25 is fitted into the second through hole 34, the locking flange portion 35 locks the protruding stopper protrusion 32 located on the hole edge 34a of the second through hole 34 from the rotational direction of the bushing 25 around the Z axis, thereby suppressing the rotation of the bushing 25.

[0135] In the illustrated example, two locking flanges 35 are formed corresponding to the two stopper projections 32.

[0136] These locking flanges 35 lock the two stopper projections 32 by pinching them from both sides of the bush 25 so as to prevent the stopper projections 32 from rotating around the bush 25 relative to the second through-hole 34 .

[0137] The locking plate 8 to which the bushing 25 is fixed is attached from the rear surface 9d of the housing 9, as shown in FIG. 10(a).

[0138] The second locking means prevents the bushing 25, which is locked and fixed at a predetermined rotational position relative to the locking plate 8 by the first locking means, from rotating on the housing 9 side.

[0139] The second locking means, which locks the stopper protrusion 32 with the locking flange 35 provided in the second through hole 34, doubly locks and fixes the bushing 25 by the housing 9 superimposed on the locking plate 8, as shown in Figure 10(c).

[0140] FIG. 11 shows the bushing 25 doubly locked by the locking plate 8 and the housing 9 .

[0141] The first locking means locks and fixes the bushing 25 to the locking plate 8 by the pressing flange 30 (groove 33) of the first through hole 27 engaging the hook 29 and the first engagement portion 31 and the stopper protrusion 32, and the second locking means locks and fixes the bushing 25 to the housing 9 by the engagement flange 35 of the second through hole 34 engaging the stopper protrusion 32 of the bushing 25, thereby doubly locking the bushing 25.

[0142] In this embodiment, the engagement with the pressing flange 30 of the bushing 25 and the locking by the locking flange 35 of the bushing 25 are ensured only by the stopper projection 32 .

[0143] However, it goes without saying that the engagement with the pressing flange 30 and the engagement by the locking flange 35 may be ensured at separate locations formed on the bush 25.

[0144] In the vehicle steering wheel device of this embodiment, a bush 25 is provided between the steering wheel 1, which is the vibration transmission path, and the airbag module 2, which is equipped with an airbag cushion 7 and other accessories and a damper unit 10 and other accessories, and which secures the coil spring 24, which is elastically deformed by horn operation and receives the reaction force accompanying the deployment and inflation action when the airbag is activated, to the airbag module 2. The bush 25 is doubly locked and secured to the airbag module 2 by a first locking means and a second locking means.

[0145] This prevents loosening or rattle from occurring at the portion where the coil spring 24 is fixed to the airbag module 2, significantly improving durability and allowing the airbag module 2 to be securely attached to the steering wheel 1.

[0146] The first locking means has a pressing flange 30 with a groove 33 in the first through hole 27 of the locking plate 8, and has a hook 29 and a pair of engagement portions (first engagement portion 31, stopper protrusion 32) in the bushing 25, so that the hook 29 is engaged with the groove 33 of the pressing flange 30 to prevent the bushing 25 from rotating, and the pair of engagement portions are engaged with the pressing flange 30 to support the bushing 25 on the locking plate 8.

[0147] The first locking means has a simple structure and yet can reliably lock and fix the bushing 25 to the locking plate 8.

[0148] The second locking means has a locking flange 35 in the second through hole 34 of the housing 9 and a stopper protrusion 32 on the bushing 25, and rotation of the bushing 25 when it is locked and fixed to the locking plate 8 by the first locking means is suppressed by the locking of the stopper protrusion 32 by the locking flange 35.

[0149] The second locking means also has an extremely simple structure, and can cooperate with the first locking means to reliably lock and fix the bushing 25 to the housing 8.

[0150] Furthermore, a strong and robust fixing structure for the bushing 25 can be secured in a narrow space approximately equal to the thickness of the housing 9 and the locking plate 8.

[0151] The vehicle steering wheel device described above is a preferred example of the present invention, and other embodiments can be implemented or performed in various ways. Unless otherwise specified in the present specification, the present invention is not limited to the shapes, sizes, and configurations of the detailed parts shown in the accompanying drawings. Furthermore, the expressions and terms used in the present specification are for explanatory purposes only, and are not intended to be limiting unless otherwise specified.

[0152] For example, two damper units 10 are provided as accessory parts at the 3 o'clock and 9 o'clock positions of an analog clock in the example, but this is not limiting. For example, an additional damper unit may be provided at the 12 o'clock position of an analog clock, or alternatively, an additional damper unit may be provided only at the 12 o'clock position of an analog clock. In other words, the number of accessory parts may be one or more (one or more).

[0153] [Appendix 1] The vehicle steering wheel device comprises a holding plate that holds accessories attached to the steering wheel 1 of the vehicle, an assembly plate that is placed over the holding plate and to which one or more accessories are attached to the steering wheel 1, a coil spring 24 that elastically supports the assembly plate that is placed over the holding plate on the steering wheel 1, and a bush 25 that is inserted through both the holding plate and the assembly plate to secure the coil spring 24, the bush 25 being locked and fixed to the assembly plate by a first locking means, and the bush 25 fixed to the assembly plate by the first locking means being locked and fixed to the holding plate by a second locking means.

[0154] [Appendix 2] In the steering wheel device described in Appendix 1, the first locking means may include: a first through hole 27 formed in the assembly plate material and through which the bushing 25 is inserted so as to be rotatable around the bushing 25; a plurality of hooks 29 formed in the bushing 25 at intervals around the bushing 25 so as to be elastically bendable; a pressing flange 30 formed in the first through hole 27 toward the inside of the first through hole 27 and elastically bending and deforming the hooks 29 moved by the rotation of the bushing 25; a pair of engaging portions formed in the bushing 25 and engaging with the pressing flange 30 from both the front and back sides as the bushing 25 rotates, thereby supporting the bushing 25 on the assembly plate material; and a groove 33 formed in the pressing flange 30 and engaging the hooks 29 so as to elastically restore the original shape of the hooks 29 moved by the rotation of the bushing 25 and prevent the rotation of the bushing 25.

[0155] [Appendix 3] In the steering wheel device described in Appendices 1 and 2, the second locking means may be characterized in that it includes a second through hole 34 formed in the holding plate material and through which the bush 25 locked and fixed to the assembly plate material by the first locking means is inserted, and a stopper protrusion 32 formed on the bush 25 facing outward from the bush 25, and the second through hole 34 has a locking flange portion 35 formed inward of the second through hole 34 and locking the stopper protrusion 32 to prevent rotation of the bush 25.

[0156] [Appendix 4] In the steering wheel devices described in Supplementary Notes 1 to 3, one or more accessory parts may be provided at the 3 o'clock and 9 o'clock positions of the assembly plate when the steering angle of the steering wheel 1 is zero.

[0157] [Appendix 5] In the steering wheel devices described in Supplementary Notes 1 to 4, one or more of the accessory parts may be a damper unit 10.

[0158] [Appendix 6] The steering wheel device described in Appendices 1 to 5 may further include a connecting member 12 that connects the holding plate to the steering wheel 1, and the connecting member 12 may be located at the 6 o'clock position of the steering wheel 1 when the steering angle of the steering wheel 1 is zero.

[0159] [Appendix 7] In the steering wheel device described in Supplementary Note 6, the connecting member 12 may connect the holding plate to the steering wheel so as to be slidable in a direction parallel to the axis of the coil spring 24. [Explanation of symbols]

[0160] 1 steering wheel 7 Airbag cushion 8 Locking Plate 8c Back of the locking plate 9. Housing 9d Back of the housing 10 Damper unit 24 coil springs 25 Bush 27 First through hole 29 Hook 30 Pressing flange 31 first engagement portion 32 Stopper protrusion 33 Groove 34 Second through hole 35 Locking flange

Claims

1. a holding plate for holding an accessory to the steering wheel of the vehicle; an assembly plate provided on the holding plate and adapted to assemble one or more accessory parts to the steering wheel; a coil spring that elastically supports the assembly plate, which is formed by overlapping the holding plate, on the steering wheel; a bushing that is inserted through both the holding plate and the assembly plate in order to fix the coil spring; The bushing is locked and fixed to the assembly plate by a first locking means, The bushing fixed to the assembly plate by the first locking means is then locked and fixed to the holding plate by the second locking means.

2. The first locking means is a first through hole formed in the assembly plate member, through which the bushing is inserted so as to be rotatable around the bushing; a plurality of hooks formed on the bush at intervals around the bush so as to be elastically bendable; a pressing flange portion formed in the first through hole toward the inside of the first through hole, the pressing flange portion elastically bending and deforming the hook that is moved by rotation of the bushing; a pair of engaging portions formed on the bushing, which engage with the pressing flange portion from both the front and rear sides as the bushing rotates, thereby supporting the bushing on the assembly plate; 2. The steering wheel device for a vehicle according to claim 1, further comprising a groove formed in the pressing flange for allowing the hook, which is moved by the rotation of the bush, to elastically restore its original shape and for engaging the hook so as to prevent the rotation of the bush.

3. The second locking means is a second through hole formed in the holding plate and through which the bushing, which is locked and fixed to the assembly plate by the first locking means, is inserted; The bushing includes a stopper projection formed outward from the bushing, The vehicle steering wheel device according to claim 1 or 2, characterized in that the second through hole has a locking flange portion formed toward the inside of the second through hole and locking the stopper protrusion so as to prevent rotation of the bush.

4. 3. The vehicle steering wheel device according to claim 1, wherein the one or more accessory parts are provided at positions of the assembly plate material at 3 o'clock and 9 o'clock when the steering angle of the steering wheel is zero.

5. 5. The vehicle steering wheel apparatus according to claim 4, wherein the at least one accessory part is a damper unit.

6. a connecting member that connects the holding plate to the steering wheel, 3. The vehicle steering wheel device according to claim 1, wherein the connecting member is provided at a position in the six o'clock direction of the steering wheel when the steering angle of the steering wheel is zero.

7. 7. The vehicle steering wheel apparatus according to claim 6, wherein the connecting member connects the holding plate to the steering wheel so as to be slidable in a direction parallel to the axis of the coil spring.

Images