JP2007082880A - Steering structure for small-sized electric vehicle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a steering structure for small-sized electric vehicles which easily agrees with the direction of front wheels in the direction of a steering wheel by forming to adjust phase shifting at mounting the steering wheel due to shape errors caused by the complicated steering structure. <P>SOLUTION: The steering structure for small-sized electric vehicles travelling by steering the right and left front wheels by manipulating the steering wheel is equipped with an angle adjusting mechanism comprising a flange part 10 provided at the upper end of a steering shaft and a steering wheel mounting part 13 and has a long hole 17 at the steering wheel mounting part 13. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a steering structure suitable for use in a four-wheeled small electric vehicle for use by an elderly person or a person with reduced mobility.

  Small electric vehicles are classified as self-operating handle type wheelchairs, and are extremely useful as substitutes for elderly people. In the basic configuration of such a small electric vehicle, for example, a seat on which the occupant sits is installed at the rear of the vehicle body, a floor for the occupant to put his / her foot on is provided in front of the seat, and a steering shaft for steering the front wheels in front of the seat. Is established. A handle is attached to the upper end of the steering shaft, and an occupant is seated on the seat and operates the handle.

  In this kind of small electric vehicle, the basic structure of the steering system that transmits the steering operation to the wheels is that one end of the steering shaft is fixed to the tie rod arm, and the tie rod arm is connected to one end of the tie rod arranged symmetrically, The other end of the tie rod is connected to the wheel via a knuckle arm. A handle is fixed to the other end of the steering shaft. By comprising in this way, a driver | operator's steering wheel operation is transmitted to a wheel as rotational motion.

  On the floor where passengers put their feet, the expansion of the space can be given as a user merit. In order to secure the floor space, the steering shaft standing in front of the floor and the shaft to which the handle is fixed are separated as separate parts, for example, bent through a universal joint or the like, and the steering shaft and the tie rod arm are connected. Various devices have been devised, such as separating the shaft as a separate part and connecting it with a link member to transmit rotational motion. In some cases, the steering system is configured by bending the steering shaft so as to ensure sufficient floor space, extending the steering shaft to a position where the driver can easily operate, and attaching a handle.

  As a prior art of a steering wheel mounting structure in a steering system, there is a technique such as Patent Document 1 in which a handle bar can be directly mounted on a support bracket integrated with a steering shaft. According to this technology, the handlebar can be easily removed when the handle is repaired or modified, and therefore, it is excellent in maintainability.

JP 2000-237245 A

  Each component in the steering system is connected, for example, a connecting portion between the steering shaft and the tie rod arm is provided with a gear or the like, and each component is mainly fixed by welding. In addition, bending the steering shaft to ensure space as described above increases the number of intervening parts such as a universal joint, and accordingly increases the number of welds.

  The increase in the number of parts results in the accumulation of dimensional errors unique to the part, and the increase in weld locations results in the accumulation of shape errors due to welding. When the handle is mounted, the accumulation of both errors causes the wheel direction and the handle direction to deviate. It tends to cause phase shift.

  Also, increasing the number of integrated parts or increasing the welding accuracy to improve the component accuracy is not necessarily suitable because it may lead to an increase in cost and weight, resulting in a rise in sales price and a deterioration in the cruising range. It's hard to say.

  Further, when the above-described steering shaft and tie rod arm are provided with a separate shaft and connected by a link member, the phase shift can be adjusted by using a pillow ball and a rod for the link member. However, it is necessary to enlarge the link member as the steering angle increases, which may limit the component layout and floor space. Moreover, since the number of parts increases, it is not necessarily preferable.

  In view of the actual situation, the present invention makes it possible to easily adjust the direction of the front wheel and the direction of the steering wheel by making it possible to adjust the phase shift at the time of mounting the steering wheel due to the shape error that may occur as the steering structure becomes complicated. Provided is a steering structure for a small electric vehicle capable of achieving the above.

  The present invention is a steering structure for a small electric vehicle that travels by steering left and right front wheels by operating a handle, and is characterized in that a handle angle adjusting mechanism is provided at a joint portion between the steering shaft and the handle.

  The handle angle adjusting mechanism includes a flange portion provided at an upper end of the steering shaft and a handle attachment portion, and has a plurality of fastening holes on both sides, and the handle portion adjustment portion includes at least one of the flange portion and the handle attachment portion. The fastening hole is a long hole.

  Further, the arrangement of both the fastening holes or the long holes is configured so that the mounting angle of the handle mounting portion can be changed by 90 degrees.

  Further, the steering shaft is configured to bend and tilt toward the rear of the vehicle.

  According to the present invention, by providing a handle angle adjusting mechanism in the attachment of the steering wheel and the steering shaft, the phase of the front wheel and the steering wheel from the accumulation of dimensional errors due to the intervention of parts that can occur in the steering system and the accumulation of shape errors due to welding. The shift can be adjusted by turning.

  Further, the handle attachment angle can be easily changed, and in particular, when it is configured to be able to rotate 90 degrees, the handle can be arranged at a position close to the driver, so that the usability is improved.

  DESCRIPTION OF EMBODIMENTS Hereinafter, a preferred embodiment of a steering structure in a small electric vehicle according to the present invention will be described with reference to the drawings. FIG. 1 is a side view showing an overall configuration of a small electric vehicle 100 according to an embodiment of the present invention, FIG. 2 is a front view, and FIG. 3 is a plan view. First, the overall configuration of the small electric vehicle 100 in the present embodiment will be described. In the small electric vehicle 100, a pair of left and right front wheels 102 and a pair of left and right rear wheels 103 are supported by a body frame 101 via a suspension (not shown). The body frame 101 is covered with a resin cover including a front cover 104, a leg shield 105, a floor 106, a rear cover 107, and the like, except for a part thereof.

  A substantially box-shaped rear cover 107 projects upward at the rear of the vehicle body, and components (not shown) for driving the left and right rear wheels 103 on the inner side of the rear cover 107, such as a drive motor and a drive. A gear unit, a battery, and the like that transmit the output of the motor to the axle are accommodated.

  A seat 109 on which a passenger sits is mounted on the upper side of the rear cover 107 via a bracket 108 that rises in a gate shape from the body frame 101. The seat 109 includes a seat cushion 110 and a seat back (backrest) 111, and is supported on the rear cover 107 so as to be turnable in the horizontal direction.

  Further, armrests 112 are provided on both sides of the seat back 111, and each armrest 112 is supported so as to be rotatable around a fulcrum 113. A blinker may be provided on each side surface of each armrest 112.

  The leg shield 105 protrudes upward at the front of the vehicle body, and protects the wind and the like around the legs of the passenger seated on the seat 109. A steering shaft 114 for steering the front wheel 102 and a handle shaft 115 (FIG. 1, broken line) connected to the upper end of the steering shaft 114 are erected in the leg shield 105. A handle unit 116 is attached to the upper end of the handle shaft 115. The driver sits on the seat 109 and grips and operates the handle unit 116. In addition, rear view mirrors 117 are arranged at right and left at appropriate positions of the handle unit 116.

  In the front part of the leg shield 105, a front basket 118 that can be used as a storage basket is mounted at a position lower than the handle unit 116, and the front basket 118 can be used as a container as appropriate.

  The handle unit 116 has a handle main body 119 having substantially the same left and right width as that of the front basket 118, and constitutes a substantially rectangular loop handle. In addition, an operation / display device 121 used when the vehicle travels is mounted on the upper surface of the switch box 120 arranged at the approximate center.

  A pair of accelerator levers 122 extending from both sides of the switch box 120 are mounted symmetrically inside the handle body 119. The accelerator lever 122 is substantially C-shaped and is configured along the handle main body 119. The accelerator lever 122 is located above the handle main body 119 in the vehicle rear (Rr) side portion, and the vehicle rear (Rr) side of the handle main body 119. The portion extends substantially parallel to the straight bar portion of the part and has a shape that follows. Further, the vehicle front (Fr) side portion is positioned below the handle main body 119, extends substantially parallel to the straight bar portion of the handle main body 119 on the vehicle front (Fr) side portion, and further curves to bend the handle main body 119. The shape is along the short side. By configuring the accelerator lever 122 in this way, the driver can operate the accelerator without any trouble while holding the handle body 119 at an appropriate position according to the physique of the driver. Further, a brake lever 123 extends to the left at the front of the switch box 120.

  Next, a steering system including the steering shaft 114 and the handle shaft 115 will be described with reference to FIGS.

  FIG. 4 is a cross-sectional view showing the connection relationship between the handle shaft 115 and the steering shaft 114 and the connection relationship with the tie rod arm 133 at the lower end of the steering shaft 114. Reference numeral 115 denotes a handle shaft, which will be described in detail later. A handle unit 116 is attached to the upper end of the handle shaft. The handle shaft 115 is connected to the steering shaft 114 via a universal joint 124 at the lower end. In this way, by connecting with the universal joint 124, it becomes possible to bend, and a sufficient space of the floor 106 can be secured. The universal joint 124 and the handle shaft 115 are welded, and the steering shaft 114 and the universal joint 124 are spline-fitted.

  Further, the upper end of the auxiliary shaft 126 formed integrally with the gear 125 is welded to the lower end of the steering shaft 114. The lower end side of the auxiliary shaft 126 is pivotally supported via a bearing (preferably a resin bush) (not shown) on an auxiliary shaft mounting boss 128 provided on a bracket 127 supported by welding to the vehicle body frame 101. The bracket 127 is also provided with a counter shaft mounting boss 129, and the counter shaft 131 to which the gear 130 is fixed is pivotally supported by the boss 129 via a bearing 132. Further, a tie rod arm 133 is welded to the lower end of the counter shaft 131, the gear 125 and the gear 130 mesh with each other, and the rotational movement of the handle unit 116 is transmitted to the tie rod arm 133.

  Next, a perspective view of the handle shaft 115 is shown in FIG. The handle shaft 115 is made of a round pipe material or the like, and its lower end is connected to the upper end of the steering shaft 114 via the universal joint 124 as described above. The flange portion 10 for fastening the handle shaft 115 to the handle unit 116 is welded to the upper end of the handle shaft 115. The flange portion 10 is made of a metal plate, and its peripheral edge is bent to form an edge portion. Further, in the approximate center of the flange portion 10, there is a fitting hole 11 having approximately the same diameter as the handle shaft 115, and welding is performed with the handle shaft 115 fitted in the fitting hole 11. A plurality of bolt holes 12 are formed so as to surround the fitting hole 11. In the present embodiment, the bolt holes 12 are formed at three points of approximately 120 degrees equidistant. Although details will be described later, the bolt inserted into the elongated hole 17 of the handle mounting portion 13 is screwed into the bolt hole 12.

  Furthermore, the handle attachment portion 13 is shown in FIG. The handle attachment portion 13 is molded into a rectangular flat plate that is punched out in place for a light-weight or through hole for wiring of an electrical system such as the display device 121 attached to the switch box 120. Further, two bolt holes 14 for attaching the handlebars are disposed near both ends in the longitudinal direction (vehicle longitudinal direction). Further, a flange fitting portion 15 that protrudes downward is formed in the approximate center of the handle attachment portion 13. The flange fitting portion 15 is fitted into the flange portion 10 and is restrained by an edge portion formed on the periphery of the flange portion 10, prevents falling off, and is maintained in a stable state at the time of bolt fastening. Further, the flange fitting portion 15 has a through hole 16 having approximately the same diameter as that of the handle shaft 115 at a substantially center thereof, and is configured so that the upper end portion of the handle shaft 115 can be inserted. Further, three long holes 17 are formed at equal intervals of approximately 120 degrees so as to surround the through holes 16, and the positional relationship of the long holes 17 is approximately the same as the position of the bolt holes 12. Further, the handle attachment portion 13 has a bolt inserted through the elongated hole 17 and is screwed into the bolt hole 12 provided in the flange portion 10 described above.

  Details of the fastening of the handle unit 116 and the handle shaft 115 will be described with reference to FIG. In FIG. 7, the handle bar 134 has a substantially rectangular shape and is molded so as to cut off the central portion of one side of the long side, thereby forming a loop handle. In addition, a soft material such as urethane is fixed by a mold and a mold part 135 is attached to form a grip part suitable for the driver.

  A stay 136 having a bolt insertion hole for attaching a handle is disposed in each of the vehicle front and rear directions of the handle bar 134, and the handle bar 134 is fastened by the bolt hole 14 and the bolt of the handle attaching portion 13 described above. In this manner, the handle bar 134 can be attached and detached, and a handle having excellent maintainability such as repair and modification can be obtained. Further, a rear view mirror mounting bracket 137 and the like are attached to the handle bar 134.

  As shown in FIG. 7, the handle unit 116 and the handle shaft 115 are fastened by fastening the bolt insertion hole of the stay 136 and the bolt hole 14 of the handle attachment portion 13 with bolts as shown in FIG. 13 and the bolt hole 12 of the flange portion 10 are fastened with bolts.

  As described above, the angle adjustment mechanism according to the embodiment of the present invention is configured by providing the flange portion 10 and the handle attachment portion 13. In attaching the flange portion 10 and the handle attachment portion 13 that fasten the elongated hole 17 and the bolt hole 12, a gap is generated in the elongated hole 17 when the bolt is inserted. Using this gap, it is possible to rotate and adjust the phase difference from the accumulation of dimensional errors due to intervening parts and the accumulation of shape errors due to welding that occurs in the steering system (handle unit 116 to tie rod arm 133) of the present embodiment. .

  Details of the phase difference assumed in the present embodiment causing the above-described phase difference will be described. When the center of the tie rod arm 133 that is the center of the steering operation of the vehicle is aligned with the vehicle traveling direction, first, an error occurs in the welding of the counter shaft 131 that is welded to the tie rod arm 133 (FIG. 4, a).

  Further, the gear 130 for transmitting the steering force meshes with the gear 125. Since the gear 125 is formed integrally with the auxiliary shaft 126, the auxiliary shaft 126 is welded to the lower end of the steering shaft 114, and an error occurs (FIG. 4, b).

  Further, the upper end of the steering shaft 114 is welded with a spline shaft for coupling with the universal joint 124 to cause an error (FIG. 4, c), and the handle shaft 115 is welded with one end of the universal joint 124. An error occurs (FIG. 4, d).

  If the handle attachment portion 13 is directly welded to the handle shaft 115, when the handle bar 134 is attached, a phase difference (a + b + c + d) due to accumulation of welding errors occurs. When this welding error is accumulated in the same direction, if the tie rod arm 133 is moved straight, it seems that the handle is tilted due to the phase difference, which causes a user complaint.

  Therefore, in the present invention, in the structure in which the flange portion 10 and the handle mounting portion 13 are fastened as in the present embodiment, the fastening hole of the handle mounting portion 13 is the long hole 17 and the size of the long hole 17 is changed. It is possible to easily avoid the phase difference by configuring so that the rotation can be adjusted within an angle range (FIG. 6, e) having a margin more than the phase difference (a + b + c + d).

  In the present embodiment, the bolt holes 12 of the flange portion 10 and the elongated holes 17 of the handle mounting portion 13 are arranged at approximately 120 degrees equidistant three points, but the positions and sizes thereof are particularly limited. The number is not limited to the above and may be other than the above number. For example, if the positions of the bolt holes 12 and the long holes 17 are arranged concentrically, the handle unit 116 can be attached to a position that is appropriately rotated. In particular, the handle unit 116 is rotated 90 degrees by making the long hole 17 into a long hole having a sufficient length and by arranging the bolt hole 12 and the long hole 17 in an even number such as four or eight. (FIG. 8).

  As described above, since the position of the handle unit 116 can be changed, the driver can adjust his / her preference. In particular, a driver with a single arm disability can provide a handle that is easy to use because the handle can be placed close to his / her body. At this time, since the accelerator lever 122 in the present embodiment extends along each side of the handle main body 119, the accelerator operation can be performed without any trouble even when the handle is disposed at a rotated position. .

  Further, the flange portion 10 and the handle attachment portion 13 are provided with a plurality of fastening holes and can be fastened with a plurality of bolts, and are not restricted by the diameter of the handle shaft 115. Large torque can be transmitted compared to the structure.

  The implementation of the present invention is not limited to the steering system in the present embodiment. For example, even in a steering shaft that is not bent via a universal joint, there is naturally interposition of parts and welding in a tie rod arm connecting portion or the like, so that the present invention can be suitably implemented.

  Further, even when the joint is not connected by welding, for example, when the universal joint is fixed to the steering shaft by serration, the steering structure of the present invention can suitably cope with a shape error that may occur.

  Further, in the present embodiment, the long hole 17 is provided in the handle mounting portion 13, but the long hole may be provided in the flange portion 10 and the bolt hole may be provided in the handle mounting portion 13. Moreover, although there is no limitation in the magnitude | size of the long hole 17, it is desirable to set it as the arrangement | positioning which considered the stability at the time of attachment, and a rigid surface.

  The handle shaft used in the present embodiment is conceptually the same as the steering shaft.

1 is a side view of a small electric vehicle according to an embodiment of the present invention. 1 is a front view of a small electric vehicle according to an embodiment of the present invention. 1 is a plan view of a small electric vehicle according to an embodiment of the present invention. It is principal part sectional drawing of the small electric vehicle which concerns on embodiment of this invention. It is a figure which shows the component of the small electric vehicle which concerns on embodiment of this invention. It is a figure which shows the component of the small electric vehicle which concerns on embodiment of this invention. It is a figure which shows the mode of the assembly of the principal part of the small electric vehicle which concerns on embodiment of this invention. It is a figure which shows the example which rotated the handle | steering-wheel of the small electric vehicle which concerns on embodiment of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Flange part 11 Fitting hole 12 Bolt hole 13 Handle attachment part 14 Insertion hole 15 Flange fitting part 16 Through hole 17 Long hole 100 Small electric vehicle 101 Body frame 102 Front wheel 103 Rear wheel 104 Front cover 105 Leg shield 106 Floor 107 Rear cover 108 Bracket 109 Seat 110 Seat cushion 111 Seat back 112 Armrest 113 Support point 114 Steering shaft 115 Handle shaft 116 Handle unit 117 Rear view mirror 118 Front basket 119 Handle body 120 Switch box 121 Display device 122 Acceleration lever 123 Brake lever 124 Universal joint 125 Gear 126 Auxiliary shaft 127 Bracket 128 Boss 129 Boss 130 Gear 131 Cow Center shaft 132 Bearing 133 Tie rod arm 134 Handle bar 135 Mold part 136 Stay 137 Bracket

Claims (5)

  A steering structure for a small electric vehicle that travels by steering left and right front wheels by operating a steering wheel, wherein a steering angle adjusting mechanism is provided at a joint between the steering shaft and the steering wheel.   The handle angle adjusting mechanism includes a flange portion provided at an upper end of a steering shaft and a handle attachment portion, and has a plurality of fastening holes on both sides, and the fastening hole in at least one of the flange portion or the handle attachment portion. The steering structure for a small electric vehicle according to claim 1, wherein is a long hole.   The steering structure for a small electric vehicle according to claim 2, wherein the fastening holes are arranged so that the attachment angle of the handle attachment portion can be changed by 90 degrees.   The steering structure for a small electric vehicle according to claim 2, wherein the size of the elongated hole is configured so that the attachment angle of the handle attachment portion can be changed by 90 degrees.   The steering structure for a small electric vehicle according to any one of claims 1 to 4, wherein the steering shaft is configured to bend and tilt toward the rear of the vehicle at a predetermined height.

Images