JP2007037884A - Electric small vehicle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an electric small vehicle having an electrical motor in a cantilever support structure capable of ensuring support rigidity of running wheels. <P>SOLUTION: The electric small vehicle 1 comprises a frame 2, a pair of left and right running wheels 4, 4' supported by a wheel support part 5c of the frame 2, and electric motors 9, 9' which are arranged in a hub 4c of the running wheels 4, 4' for supplying motor driving force to the running wheels 4, 4', wherein the electric motors 9, 9' are axial-gap type equipped with a rotor 19 arranged at the same axis with the axle for rotating together with the running wheels 4, 4' and a stator 18 fixed at the frame side so as to face the rotor 19 in the axis direction, and it is arranged on the inner side of the center line of the width direction of the running wheels. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to an electric small vehicle such as an electric wheelchair, and more particularly to an improvement in the arrangement structure of an electric motor.

For example, some electric wheelchairs are provided with a power unit in which a motor and a planetary gear speed reduction mechanism are integrated in a hub of a traveling wheel (see, for example, Patent Document 1). In this conventional power unit, the DC electric motor 65 including the transmission device 38 is disposed in the wheel hub 10 without a protrusion.
Japanese Patent Publication No. 7-53169

  By the way, the conventional power unit employs a so-called cantilever support structure in which the traveling wheel is supported by the vehicle body frame by inserting the insertion shaft 13 protruding from the housing 20 into the adapter sleeve 15 on the vehicle body side. On the other hand, the electric motor 65 is disposed so as to substantially coincide with the center line in the vehicle width direction of the traveling wheel. Therefore, the amount of overhang from the body frame of the heavy electric motor 65 increases, and there is a problem that it is difficult to ensure the support rigidity of the traveling wheels.

  The present invention has been made in view of the above-described conventional situation, and an object of the present invention is to provide an electric small vehicle that can secure the support rigidity of the traveling wheel while the electric motor has a cantilever support structure.

  The invention according to claim 1 is a frame, a pair of left and right traveling wheels supported by wheel support portions of the frame, and an electric motor disposed in a hub of the traveling wheels and supplying driving force to the traveling wheels. The electric motor is fixed to the frame side so as to face the rotor in the axial direction, and a rotor coaxially arranged with the axle so as to rotate together with the traveling wheel. It is an axial gap type provided with a stator, and is arranged to be located on the inner side in the vehicle width direction from the center line in the vehicle width direction of the traveling wheel.

  According to a second aspect of the present invention, in the first aspect, the electric motor is disposed so as to be positioned between the center line in the vehicle width direction and the wheel support portion of the frame.

  According to a third aspect of the present invention, in the second aspect, the rotor includes a disc-shaped holding plate and a magnet arranged and fixed on the outer peripheral portion of the holding plate so as to face the stator in the axial direction. The holding plate has a recessed portion that is recessed so as to be located on the inner peripheral side of the stator, and at least a portion of the recessed portion and the stator overlap when viewed in the radial direction. It is characterized by.

  According to a fourth aspect of the present invention, in the third aspect, the electric motor is housed and disposed in a fixed case, and the fixed case is fixed to a wheel support portion of the frame via a mounting rod, and the fixing rod is fixed. An end portion of the boss portion attached to the case is located in the concave portion of the holding plate.

  According to a fifth aspect of the present invention, there is provided a planetary gear mechanism that decelerates the rotation of the electric motor and transmits it to the traveling wheel according to the first aspect, and the planetary gear mechanism is mostly in the hub and the vehicle. It is arranged so as to be located on the outer side in the vehicle width direction from the center line in the width direction.

  According to a sixth aspect of the present invention, in the first aspect, the motor control controller for controlling the rotation of the electric motor is disposed in the hub and on the outer side in the vehicle width direction from the electric motor. It is a feature.

  A seventh aspect of the present invention is the clutch mechanism according to the first aspect, wherein the clutch mechanism is disposed in a driving force transmission system that transmits the driving force of the electric motor to the traveling wheel, and the clutch mechanism that turns on / off transmission of the driving force And a clutch lever for switching between ON and OFF, and the clutch lever is disposed between the traveling wheel and the wheel support portion of the frame.

  According to an eighth aspect of the present invention, in the first aspect, a brake device is attached to the traveling wheel, and the brake device includes a cylindrical brake drum fixed to the hub, and an inner peripheral surface of the brake drum. And inner and outer brake shoes arranged so that the outer peripheral surface can be clamped in the radial direction.

  According to the first aspect of the present invention, since the electric motor is of an axial gap type in which the rotor and the stator are disposed so as to face each other in the axial direction, the conventional electric motor that causes the rotor and the stator to face each other in the radial direction. Compared with the motor, the radial dimension of the electric motor and thus the power unit can be made compact.

  Since the electric motor is disposed so as to be located on the inner side in the vehicle width direction from the center line in the vehicle width direction of the traveling wheel, the amount of overhang from the frame of the heavy electric motor can be reduced. In particular, as in the second aspect of the invention, when it is arranged so as to be positioned between the vehicle width direction center line and the wheel support portion of the frame, the overhang amount can be further reduced. As a result, it is possible to increase the support rigidity of the traveling wheel while adopting the cantilever support structure.

  In the invention of claim 3, the rotor is arranged and fixed on a disc-shaped holding plate so that the magnet faces the stator in the axial direction, and a concave portion is formed in the center of the holding plate, The concave portion and at least part of the stator are configured to overlap when viewed in the radial direction. Therefore, the axial length of the electric motor can be further reduced, the amount of overhang from the frame of the electric motor can be further reduced, and the support rigidity of the traveling wheel can be increased.

  In the invention of claim 4, since the end of the mounting boss portion of the mounting rod for fixing the fixing case to the frame side is positioned in the recess of the holding plate, the overhang amount of the electric motor is further increased. It can be made smaller, and the support rigidity of the traveling wheel can be further increased.

  In the invention of claim 5, the planetary gear mechanism is arranged so that most of the planetary gear mechanism is located in the hub and outside the vehicle width direction center line in the vehicle width direction. It is located on both sides of the center line in the width direction, and the weight balance in the vehicle width direction when viewed with the entire traveling wheel can be improved.

  According to the sixth aspect of the present invention, since the motor control controller is disposed so as to be located on the outer side in the vehicle width direction from the electric motor, the maintainability can be improved. That is, by removing the traveling wheel unit comprising the hub, rim and tire from the power unit, the controller can be inspected and maintained from the outside, and the maintainability can be improved.

  In the invention of claim 7, since the clutch lever for switching the clutch mechanism to the on / off state is disposed between the traveling wheel and the wheel support portion of the frame, even a user with a disability is seated. Thus, the clutch lever can be easily operated, and manual traveling when the clutch mechanism is turned off and electric traveling when the clutch mechanism is turned on can be freely selected.

  In the invention of claim 8, the brake device includes a brake drum fixed to the hub, and inner and outer brake shoes arranged so as to be able to sandwich the inner and outer peripheral surfaces of the brake drum in the radial direction. Therefore, it becomes possible to add a brake device by retrofitting, and versatility can be improved.

  Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.

  1 to 15 are views for explaining an electric wheelchair according to an embodiment of the present invention. Note that front and rear and left and right in this embodiment mean front and rear and left and right when viewed in a wheelchair.

  In each figure which shows the structure of the said wheelchair, 1 is the electric wheelchair which concerns on this embodiment. This wheelchair 1 includes a body frame 2, small-diameter left and right front wheels 3, 3 'disposed at the front of the body frame 2, and large-diameter left and right traveling wheels 4, 4 disposed at the rear. ′. The vehicle body frame 2 has a schematic structure in which left and right side frames 5, 5 'are connected to each other by a plurality of cross frames. The side frame 5 has a schematic structure in which upper and lower pipes 5a and 5b extending in the front-rear direction are connected by a plurality of vertical pipes 5c. A board support pipe 5d extends downward from the front end portions of the left and right side frames, and the footboard 6 is supported by the board support pipe 5d. A handle pipe 5e is formed at the rear end of the side frame 5 so as to extend upward. A steering handle 5f is attached to the handle pipe 5e, and an operation box 60 operated by an assistant is disposed on the handle 5f.

  Further, a support column 7 is disposed so as to stand upward at the front end portion of the right side frame 5 '. An operation box 8 is mounted on the upper end portion of the column 7, and a joystick 8 a that functions as an input means for giving an input rotation command value to electric motors 9 and 9 ′ described later is disposed in the operation box 8. . When the joystick 8a is tilted forward, it moves forward, when it is tilted backward, it moves backward, and when it is tilted left or right, it turns left or right.

  The operation box 8 can be adjusted in its vertical position, front-rear direction position, and vehicle width direction position by the following structure. By this adjustment, the position of the joystick 8a can be adjusted to a position that can be easily operated by the user.

  The rear upper part of the holder 7a attached to the lower end portion of the column 7 is fastened and fixed to the board support pipe 5d of the right side frame 5 together with the pipe clamp 7b by a bolt 7c. The rear lower portion of the holder 7a is fastened and fixed to the arc-shaped long hole 7h portion of the support plate 7e by a bolt 7d. Furthermore, the inclined long hole 7i portion at the front of the support plate 7e is fastened and fixed to the board support pipe 5d together with the pipe clamp 7g by a bolt 7f.

  In addition, a silado pipe 8b is inserted into the support column 7. A support 8e is fastened and fixed by a bolt 8d to a support 8c fixed to the upper end of the ride pipe 8b. Further, a wedge member 8f is screwed to the lower end of the bolt 8d, and the slide pipe 8b can be moved up and down by loosening the bolt 8d and fixed by tightening at an arbitrary position.

  Furthermore, a ball holder 8i for holding a ball joint 8g formed on the lower surface of the operation box 8 is fastened and fixed to the support 8e with bolts 8j. The ball joint 8g is fixedly supported by the ball holder 8i by tightening a bolt 8h.

  In order to move the operation box 8 slightly forward and backward as it is, the bolts 7c, 7d and 7f are loosened, the support column 7 is moved back and forth together with the pipe clamp 7b, and then the bolts 7c, 7d and 7f are fastened and fixed. When the operation box 8 is moved back and forth relatively large, the bolts 7c and 7d are loosened, the support column 7 is rotated back and forth around the bolt 7c, and then the bolts 7c and 7d are tightened. At this time, since the operation box 8 is tilted back and forth, the bolt 8h is loosened and the operation box 8 is rotated around the ball joint 8g so as to be in a horizontal state.

  In order to move the operation box 8 up and down, the bolt 8d is loosened and the slide pipe 8b is expanded and contracted up and down. At this time, the operation box 8 can be rotated horizontally around the slide pipe 8b, thereby adjusting the position in the vehicle width direction.

  The front wheel holder 3a is supported by the vertical pipe 5c at the front end so as to be able to turn around the axis of the vertical pipe 5c, and the front wheel 3 is rotatably supported by the front wheel holder 3a. The left and right traveling wheels 4 and 4 'are detachably supported by left and right vertical pipes 5c and 5c' at the rear end by a structure which will be described later.

  The left and right traveling wheels 4, 4 'are symmetrical with respect to the vehicle center line and basically have the same structure. The battery 30 is fixed to the fixed case 14 of the right traveling wheel 4 '. The left and right traveling wheels 4, 4 'have a structure in which a ring-shaped rim 4b on which a tire 4a is mounted and a bottomed cylindrical hub 4c are connected by a large number of spokes 4d. In the present embodiment, the straight line A passing through the center in the axial direction (vehicle width direction) of the tire 4a and the rim 4b is referred to as the center line in the width direction of the left and right traveling wheels 4, 4 ′.

  Inside the hub 4c, power units 31, 31 'for generating the rotational driving force of the left and right traveling wheels 4, 4' are disposed. The left and right power units 31, 31 'serve as left and right electric motors 9, 9' and a driving force transmission system for transmitting the rotational driving force of the electric motors 9, 9 'to the traveling wheels 4, 4'. Left and right planetary gear mechanisms 10 and 10 'functioning, and left and right dog clutches 11 and 11' functioning as left and right mechanical clutch mechanisms for turning on and off the transmission of the driving force are provided.

  Further, in the hub 4c, clutch detection switches 12, 12 'functioning as clutch detection means for detecting the on / off state of the dog latches 11, 11' and the clutch detection switches 12, 12 'are detected. Left and right motor drivers 13 and 13 'for controlling the rotation of the electric motors 9 and 9' according to the on / off states of the dog clutches 11 and 11 'are provided.

  Here, when the position in the vehicle width direction of the electric motors 9, 9 ', etc. is viewed in more detail, the electric motors 9, 9' are arranged on the inner side in the vehicle width direction from the width direction center line A of the traveling wheels 4, 4 '. In addition, at least the first and second speed reduction mechanisms 23 and 24 of the planetary gear mechanisms 10 and 10 'are disposed so as to be located on the outer side in the vehicle width direction from the width direction center line A.

  The electric motor 9 and the planetary gear mechanism 10 are accommodated in the fixed case 14. The fixed case 14 is divided into two in the motor axial direction, which is a roughly dish-shaped motor case 15 and a speed reducer case 16 having a flange portion 16a and a bottomed cylindrical tube portion 16b. The outer peripheral edge of the motor case 15 and the outer peripheral edge of the flange portion 16a of the speed reducer case 16 are coupled to each other by a connecting bolt (not shown).

  Here, the power unit 31 and the traveling wheel 4 are attached to the vehicle body frame 2 in a detachable manner and the attachment angle thereof can be adjusted by the following structure.

  A mounting rod 28 is inserted into the center portion 15c of the inner side surface in the vehicle width direction of the motor case 15 so as to be positioned at the axial center of the traveling wheel 4, protrudes inward, and is secured by being snapped off by a snap ring 28b. Has been. The mounting rod 28 is inserted so as to penetrate through the wheel holding portion 5c 'formed in the vertical pipe 5c at the rear end portion in the direction perpendicular to the axis, and the vehicle inner protrusion is fastened and fixed by a nut 28a. . The wheel holding portion 5c ′ is a member having a rectangular cross section, and a positioning plate 29 is interposed between the wheel holding portion 5c ′ and the motor case 15. The positioning plate 29 is formed with a mounting hole 29a through which the mounting rod 28 passes, and two mounting pins 15b and 15b 'are implanted. These mounting holes 29a and mounting pins 15b and 15b 'are arranged so as to form a triangle. Further, two positioning slits 29c are formed in the positioning plate 29 so as to have a radial shape centered on the mounting hole 29a. The two positioning slits 29c are fitted with two of a large number of protrusions 15c projecting from the inner surface of the motor case 15 so as to have a radial shape about the axle.

  The one mounting pin 15b is in contact with the vertical pipe 5c. A fixed cam 33 is mounted on the other mounting pin 15b 'so as to be rotatable about the mounting pin 15b'. The fixed cam 33 is formed with a cam surface 33a that is eccentric with respect to the mounting pin 15b ', and the cam surface 33a presses the vertical pipe 5c more strongly as the fixed cam 33 is rotated clockwise. A bolt hole 33b is formed in an arc shape centering on the mounting pin 15b 'on the side of the fixed cam 33 opposite to the cam surface. A fixing bolt 33c is inserted into the bolt hole 33b and screwed into a boss portion 29b fixed to the positioning plate 29. The fixed cam 33 is formed with a tool hole 33d penetrating from the outer edge to the arc-shaped bolt hole 33b.

  When the fixing bolt 33c is loosened and a screwdriver or the like is inserted into the tool hole 33d and the fixing cam 33 is rotated clockwise in the figure, the vertical pipe is formed by the cam surface 33a and one mounting pin 15b. 5c is clamped. By tightening the fixing bolt 33c in this state, the power unit 31 is fixed in a state of being prevented from rotating at a desired angular position.

  The electric motors 9 and 9 'are arranged so as to be located on the motor case 15 side, and the planetary gear mechanisms 10 and 10' are arranged so as to be located on the speed reducer case 16 side.

  The electric motors 9 and 9 'are of the so-called axial gap type in which the stator 18 and the rotor 19 are arranged so as to face each other in the axial direction of the motor. The stator 18 is fixed to a side of the flange portion 16a of the speed reducer case 16 facing the motor case 15. The rotor 19 includes a disk-shaped holding plate 19a and a magnet 19b fixed to the side of the plate 19a facing the stator 18.

  A concave portion 19d is formed in the center of the holding plate 19a. When viewed in the direction perpendicular to the axis, the recess 19 d overlaps the stator 18. Further, a boss portion 28c of the mounting rod 28 that is engaged with the motor case 15 is located in the recess 19d, thereby making the dimension of the fixed case 14 in the vehicle width direction compact.

  Further, the shaft center portion 19c of the concave portion 19d is spline-fitted to the shaft center of the electric motor 9 ', that is, the input shaft 22 of the planetary gear mechanism 10' disposed at the shaft center of the traveling wheel 4 ', and further fixed. It is fixed by a nut 22a.

  The controller 13 is disposed and fixed on a rib 16c formed on the side of the flange 16a opposite to the motor. The controller 13 has an electronic circuit element 13d such as an FET mounted on a substrate 13a fixed on the rib 16c with a heat dissipation sheet 13b interposed therebetween, and the electronic circuit element 13d is covered with a heat dissipation sheet 13b and a heat dissipation plate 13c. Of the same structure.

  The planetary gear mechanism 10 is of a two-stage reduction type composed of first and second reduction mechanisms 23 and 24 arranged on the input side and the output side. The first speed reduction mechanism 23 is disposed so as to surround a first sun gear 23a formed on the outer periphery of the input shaft 22, a plurality of first planetary gears 23b meshing with the sun gear 23a, and the planetary gears 23b. A first ring gear 23c having an inner peripheral tooth meshing with each planetary gear 23b is provided.

  Here, the outer peripheral surface of the first ring gear 23c is spline-fitted to the inner peripheral surface of the holding member 23d that is bolted to the boundary portion between the cylindrical portion 16b and the flange portion 16a of the reduction gear case 16. The holding member 23d supports the input side end of the input shaft 22 via a bearing 25a. The output side end of the input shaft 22 is supported by an inner peripheral surface of a second carrier 24d described later via a bearing 25d.

  The second reduction mechanism 24 includes a second sun gear 24a formed on the outer periphery of the shaft portion of the first carrier 23e that supports the first planetary gear 23b, a plurality of second planetary gears 24b that mesh with the second sun gear 24b, And a second ring gear 24c arranged to mesh with the planetary gear 24b. The inner peripheral surface of the shaft center portion 4e of the hub 4c is spline-fitted to the outer peripheral surface of the shaft portion of the second carrier 24d that pivotally supports the second planetary gear 24b. When the second carrier 24d rotates, the hub 4c, that is, the traveling wheel 4 is rotationally driven.

  Here, the second ring gear 24c is rotatably supported by the inner peripheral surface of the cylindrical portion 16b of the speed reducer case 16. When the second ring gear 24c is fixed to the speed reducer case 16 and thus to the vehicle body frame 2, the rotation of the electric motor 9 is decelerated at a predetermined speed reduction ratio corresponding to the speed reduction ratio of the first and second speed reduction mechanisms 23 and 24. It is transmitted to the traveling wheel 4 to enable electric traveling. On the other hand, when the fixing is released, the rotation of the electric motor 9 is not transmitted, and the traveling wheels 4 and 4 ′ can rotate lightly without causing resistance on the motor side, and can be manually driven with the help of the assistant. In this embodiment, dog clutches 11 and 11 'functioning as a clutch mechanism are configured between the second ring gear 24c and the cylindrical portion 16b by utilizing this action.

  The right dog clutch 11 'has stopper pins 11b disposed in a recessed groove 11a formed at predetermined angular intervals (for example, 30 degrees) on the outer peripheral surface of the second ring gear 24c so as to be movable back and forth in the radial direction. By engaging / disengaging, the rotation of the second ring gear 24c is prevented or allowed.

  The stopper pin 11b is guided by a cylindrical guide boss portion 16d formed so as to protrude radially outward from the cylindrical portion 16b of the speed reducer case 16. A biasing spring 26 is interposed between the step portion of the stopper pin 11b and the lid member 16e. The urging spring 26 urges the stopper pin 11b in a direction to engage (engage) the concave groove 11a. A guide groove 11e is recessed in the outer surface of the stopper pin 11b so as to extend in the axial direction, and a guide pin 32d is inserted into the guide groove 11e. The guide pin 32d is provided to protrude from the reduction gear case 16. As a result, the stopper pin 11b is prevented from rotating.

  A shoe plate 12b constituting a part of the clutch detection switch 12 is fixed to the upper end portion of the stopper pin 11b by a bolt 11c. The shoe plate 12b is formed by bending a plate into an L-shaped cross section having a horizontal piece portion 12c and a vertical piece portion 12d. An upper end protrusion 11d of the stopper pin 11b is fitted to the horizontal piece 12c and is screwed with a bolt 11c, whereby the shoe plate 12b is integrated with the stopper pin 11b.

  A transmission plate 27a is disposed on the inner side in the vehicle width direction of the shoe plate 12b. A pair of locking pins 27b and 27c are implanted in the transmission plate 27a, and one of the locking pins comes into contact with the lower surface of the lateral piece 12c of the shoe plate 12b depending on the angle state of the transmission plate 27a. Accordingly, the stopper pin 11b is raised or allowed to move downward.

  The transmission plate 27a is fixed to the outer end in the vehicle width direction of the clutch shaft 27d that is pivotally supported on the upper portion of the fixed case 14. The inner end of the clutch shaft 27d in the vehicle width direction protrudes inward in the vehicle width direction from the fixed case 14, and the clutch lever 27 is coupled to the protruding portion, and the clutch lever 27 extends forward. . In the middle of the clutch lever 27, a moderation mechanism 27e for holding the lever 27 on a manual side for turning off the dog clutch 11 or an electric side for turning on the dog clutch 11 is disposed. The moderation mechanism 27e is supported by a bracket 27f, and the bracket 27f is fixed to the motor case 15. Reference numeral 27j denotes a stopper for restricting the rotation angle of the clutch lever 27, which protrudes from the motor case 15.

  A coupling plate 27g is attached to the clutch shaft 27d, and the coupling plate 27g is fixed to the clutch lever 27 by bolts 27i. The connecting plate 27g is connected to the left dog clutch via a transmission cable 27h. Therefore, when the clutch lever 27 is operated, the left and right dog clutches 11 and 11 'are simultaneously operated.

  The clutch detection switch 12 includes a switch body 12a fixed to the speed reducer case 16 side, and the shoe plate 12b fixed to the stopper pin 11b and moving up and down together with the pin 11b. A shoe 12e is attached to one end of the shoe plate 12b, and the shoe 12e presses the actuator 12f of the switch body 12a.

  Further, the non-motor side portion of the reduction gear case 16 is covered with a cover 32 made of resin and having an annular shape. The inner peripheral edge 32a of the cover 32 is fitted to the outer peripheral surface of the cylindrical portion 16b of the speed reducer case 16, and the outer peripheral edge 32b is fastened and fixed to the flange portion 16a with bolts 32c. The controller 13 and the dog clutch 11 described above are arranged in a space formed by the cover 32 and the speed reducer case 16.

  When the stopper pin 11b is engaged with the concave groove 11a, the shoe plate 12b is lowered together with the stopper pin, the shoe 12e is separated from the actuator 12f, and the switch body 12a is turned on. When the engagement between the pin 11b and the groove 11a is released, the shoe 12e rotates the actuator 12f to the right, and the switch body 12a is turned off.

  When the clutch lever 27 is swung to the upper manual position, the transmission plate 27a is rotated counterclockwise in FIG. 4, and the locking pin 27b raises the shoe plate 12b and thus the stopper pin 11b, thereby the stopper pin. The engagement of the second ring gear 24c of the 11b with the concave groove 11a is released, and the dog clutch 11 is turned off (see FIG. 4). At this time, the shoe 12e of the shoe plate 12b rotates the actuator 12f of the switch body 12a clockwise in the figure, and an off signal is output from the switch body 12a. Since the second ring gear 24c is rotatable, the resistance by the power unit 31 against the rotation of the traveling wheel 4 is reduced, and the assistant can lightly push and pull the wheelchair 1.

  On the other hand, when the clutch lever 27 is swung to the lower electric position, as shown in FIG. 5A, the stopper pin 11b is located between the concave groove 11a of the second ring gear 24c and the adjacent concave groove 11a. When it is located at the position, the stopper pin 11b and thus the shoe plate 12b cannot be lowered, and the clutch remains in the off state. In this case, when the second ring gear 24c is slightly rotated, the stopper pin 11b is engaged with the concave groove 11a by the urging force of the urging spring 26 as shown in FIG. As a result, the shoe plate 12b is lowered, the shoe 12e is separated from the actuator 12f of the switch body 12a, and an ON signal is output from the switch body 12a.

  The left and right traveling wheels 4, 4 ′ are equipped with manual brake devices 35, 35 ′ on the power unit 31. The brake device 35 includes a brake drum 39 that is bolted and fixed to an inner edge in the vehicle width direction of the hub 4c, and a shoe drive mechanism 40 that clamps the brake drum 39 with a brake shoe.

  The brake drum 39 has a cylindrical drum body 39a and an annular flange portion 39b integrally formed at one end thereof, and the flange portion 39b is fixed to the inner end surface of the hub 4c by a bolt 39c. Yes.

  The shoe drive mechanism 40 includes a support bracket 36 fastened and fixed to the motor case 15 with bolts 36a and 36b, an outer arm 37 and an inner arm 38 pivotally supported on the support bracket 36 via pins 36c, Outer and outer brake shoes 37a and 38a supported by outer and inner arms 37 and 38 are provided.

  An outer 42a of the brake cable 42 is screwed into the inner arm 38 and fixed with a lock nut 42c. The tie 42 d at the tip of the inner 42 b of the brake cable 42 is locked to the outer arm 37. The brake cables 42 and 42 'of the left and right brake devices 35 and 35' extend along the handle pipe 5e to the handle 5f and are connected to the brake lever 35b. When the brake lever 35 is gripped, the inner cable 42b is pulled, and the outer and inner brake shoes 37a and 38a pinch the drum body 39a.

  A plate 36d is fastened to the support bracket 36 with bolts 36f. An adjustment bolt 36e is screwed into the plate 36d. By tightening the adjusting bolt 36e, the gap between the brake shoes 37a, 38a and the drum body 39a can be adjusted. In FIG. 8, a cover 35a covers the shoe drive mechanism 40.

  When the power unit 31 is left on the vehicle body side and only the traveling wheel 4 is removed, the cap 4g is removed and the nut 24e is removed. As a result, the spline engagement between the hub 4c and the second carrier 24d can be released, and the hub 4c and the second carrier 24d can be removed from the vehicle body frame of the traveling wheels 4.

  When the traveling wheel 4 is removed together with the power unit 31, the bolt 33c of the fixed cam 33 is loosened, and the nut 28a of the mounting rod 28 is removed. Thereby, the traveling wheel 4 can be detached from the vehicle body frame together with the power unit 31.

  In the present embodiment, since the electric motor 9 is of an axial gap type in which the rotor 19 and the stator 18 are arranged so as to face each other in the axial direction, the conventional electric motor that makes the rotor and the stator face each other in the radial direction. As compared with the above, the radial dimension of the electric motor 9 and thus the power unit 31 can be made compact.

  Since the electric motor 9 is disposed so as to be positioned between the center line A of the traveling wheel 4 in the vehicle width direction and the vertical pipe 5c, the amount of overhang from the vertical pipe 5c of the heavy electric motor 9 is reduced. can do. As a result, it is possible to increase the support rigidity of the traveling wheel 4 while adopting the cantilever support structure.

  Further, the rotor 19 is configured such that a concave portion 19d is formed in the central portion of the holding plate 19a that holds the magnet 19b, and at least a part of the concave portion 19d and the stator 18 are overlapped when viewed in the radial direction. Therefore, the axial length of the electric motor 9 can be further shortened, the amount of overhang from the frame of the electric motor 9 can be further reduced, and the support rigidity of the traveling wheels can be increased.

  Further, since the mounting boss portion 28c of the mounting rod 28 for fixing the fixing case 14 to the frame side is positioned in the concave portion 19d of the holding plate 19a, the overhang amount of the electric motor 9 is also from this point. And the support rigidity of the traveling wheel can be further increased.

  In the present embodiment, the planetary gear mechanism 10 is arranged so that most of the planetary gear mechanism 10 is located inside the hub 4c and outside the vehicle width direction center line A. Therefore, the electric motor 9 and the planetary gear mechanism are arranged. 10 is located on both sides of the center line A in the vehicle width direction, and the weight balance in the vehicle width direction when viewed from the entire traveling wheel can be improved.

  Furthermore, since the controller 13 is disposed outside the electric motor 9 in the vehicle width direction, the maintainability can be improved. That is, when the traveling wheel unit including the hub 4c, the rim 4b, and the tire 4a is removed from the power unit 31 and the cover 32 is further removed, the controller 13 is exposed to the outside. Accordingly, the inspection and maintainability of the controller 13 can be improved.

  Further, in this embodiment, the clutch lever 27 for switching the dock clutch 11 to the on / off state is disposed so as to be positioned between the traveling wheel 4 and the vertical pipe 5c. Thus, the clutch lever 27 can be easily operated, and manual travel and electric travel can be freely selected.

  Further, a manual brake device 35 is provided, and the device 35 is provided with a brake drum 39 fixed to the hub 4c, and an inner side and an outer side arranged so as to be able to sandwich the inner peripheral surface and outer peripheral surface of the brake drum 39 in the radial direction. Since it was set as the structure provided with the brake shoes 37a and 38a, it becomes possible to add a brake device by retrofitting and can improve versatility.

  In addition, when the shoe drive mechanism 40 is attached to the vehicle body frame side, these operations are easy both when removing only the wheel unit and when removing the power unit together.

  16 and 17 show modifications of the structure for attaching the power unit 31 to the vehicle body frame. In this modification, the power unit 31 and the traveling wheel 4 can be attached to and detached from the vehicle body frame with a single touch by the following structure. In the figure, the same reference numerals as those in FIGS. 3 and 8 denote the same or corresponding parts.

  A mounting rod 44 is implanted in the center portion 15c of the inner side surface in the vehicle width direction of the motor case 15 so as to be positioned at the axial center of the traveling wheel 4, and protrudes inwardly. A holding cylinder 45 having a male screw on the outer periphery is disposed on the vertical pipe 5c so as to be coaxial with the traveling wheel 4, and is fastened and fixed to the vertical pipe 5c by a nut 45a. The mounting rod 44 is inserted into the holding cylinder 45, and its left end protrudes toward the inside of the vehicle. A lock ball 46 is movably disposed in the projecting portion in the radial direction. When the lock ball 46 is pushed out to the radially outer position, the lock ball 46 is locked to the end surface of the holding cylinder 45 to prevent the mounting rod 44 from moving in the axial direction.

  A push rod 47 is inserted and arranged in the axial center of the mounting rod 44 so as to be movable in the axial direction. A cam surface 47a projects from the inner end of the push rod 47. When the push rod 47 is moved to the right, the cam surface 47a pushes the lock ball 46 to the locking position, When moved in the direction, the lock ball 46 is allowed to be immersed inward in the radial direction. The push rod 47 is biased rightward by a biasing spring 48.

  The push rod 47 extends through the axial center of the input shaft 22 to the vicinity of the inner surface of the cap 4g, and a rubber cover 49 is attached to the outer end thereof. When the cap 4g is pushed inward, the push rod 47 moves to the left, the locking of the lock ball 46 to the holding cylinder 44 is released, and the power unit 31 and the traveling wheel 4 can be removed.

  A base end portion 50a of the positioning plate 50 is sandwiched between the head portion 45b of the holding cylinder 45 and the vertical pipe 5c. The positioning plate 50 extends downward, and a positioning ring 50c is fixed to the lower end 50b thereof. A detent pin 51 is inserted into the positioning ring 50c. The anti-rotation pin 51 is screwed and fixed to the motor case 15.

  A protrusion 52 a formed at the tip of the fixed plate 52 is fitted in the locking hole 50 d formed in the middle of the positioning plate 50. A nut member 52b is fixed to the base end portion of the fixing plate 52, and a fixing bolt 53 inserted from the inside of the vertical pipe 5c is screwed into the nut member 52b.

  When only the traveling wheel 4 is removed, the cap 4g is removed and the nut 24e is removed as in the case of the above-described embodiment.

  On the other hand, when the traveling wheel 4 is removed together with the power unit 31, the push rod 47 is moved inward by pushing the cap 4g. Then, the cam surface 47a is detached from the lock ball 46, and the lock ball 36 is allowed to be immersed inward in the radial direction. As a result, the locking of the lock ball 46 and the holding cylinder 45 is released, and the traveling wheel 4 and the power unit 31 are removed from the vehicle body frame.

  In the above embodiment, the case of an electric wheelchair has been described as an example, but the present invention can also be applied to an electric small vehicle other than a wheelchair.

1 is a left side view of an electric wheelchair according to an embodiment of the present invention. It is a rear view of the right running wheel of the wheelchair. It is a cross-sectional rear view of the hub inner part of the right running wheel. It is sectional drawing seen from the inside of the clutch part of the said right running wheel. It is operation | movement explanatory drawing of the said clutch part. It is a rear view of the operation box part of the said wheelchair. It is a side view of the said operation box part. It is the figure seen from the vehicle width direction inner side of the power unit part of the said right traveling wheel. It is the IX-IX sectional view taken on the line of FIG. It is a side view of the brake device of the said wheelchair. It is a front view of the brake device. It is a top view of the said brake device. It is XIII-XIII sectional view taken on the line of FIG. It is a side view of the brake lever part of the said wheelchair. It is a bottom view of the said brake lever part. It is a side surface of the modification of the said power unit attachment / detachment structure. It is a cross-sectional rear view of the modified example.

Explanation of symbols

1 Wheelchair (Electric small vehicle)
2 Frame 4, 4 'Left and right traveling wheels 4c Hub 5c Vertical pipe (wheel support)
9, 9 'Left, right electric motor 10, 10' Left, right planetary gear mechanism 11, 11 'Left, right dog clutch (clutch mechanism)
13 Controller 14 Fixed case 18 Stator 19 Rotor 19a Holding plate 19b Magnet 19d Recess 27 Clutch levers 28 and 44 Mounting rod 28c Mounting boss 35 Brake device 37a and 38a Brake shoe 39 Brake drum A Center line in the vehicle width direction of the running wheel

Claims (8)

A small electric type equipped with a frame, a pair of left and right traveling wheels supported by wheel support portions of the frame, and an electric motor disposed in a hub of the traveling wheels and supplying driving force to the traveling wheels A vehicle,
The electric motor is of an axial gap type including a rotor coaxially arranged with an axle so as to rotate together with the traveling wheel, and a stator fixed on the frame side so as to face the rotor in the axial direction. The electric small vehicle is disposed so as to be located on the inner side in the vehicle width direction from the center line in the vehicle width direction of the traveling wheel.   The electric small vehicle according to claim 1, wherein the electric motor is disposed so as to be positioned between the center line in the vehicle width direction and a wheel support portion of the frame.   In Claim 2, the rotor includes a disk-shaped holding plate, and a magnet arranged and fixed on an outer peripheral portion of the holding plate so as to face the stator in the axial direction. A small electric type characterized in that it has a recess recessed at the center thereof so as to be positioned on the inner peripheral side of the stator, and that the recess and at least a part of the stator overlap when viewed in the radial direction. vehicle.   The electric motor according to claim 3, wherein the electric motor is accommodated in a fixed case, the fixed case is fixed to a wheel support portion of the frame via a mounting rod, and a mounting boss portion of the mounting rod to the fixed case is provided. An electric small vehicle characterized in that an end portion is located in a recess of the holding plate.   The planetary gear mechanism according to claim 1, further comprising a planetary gear mechanism that decelerates the rotation of the electric motor and transmits the reduced speed to the traveling wheels, the planetary gear mechanism being mostly in the hub and from the vehicle width direction center line. An electric small vehicle characterized by being arranged so as to be located outside in the direction.   2. The electric small vehicle according to claim 1, wherein the motor control controller for controlling the rotation of the electric motor is disposed in the hub and on the outer side in the vehicle width direction from the electric motor. . 2. A clutch mechanism that is disposed in a driving force transmission system that transmits the driving force of the electric motor to the traveling wheel, and that switches the driving force on and off, and switches the clutch mechanism to an on / off state. A clutch lever,
The electric small vehicle, wherein the clutch lever is disposed between the traveling wheel and a wheel support portion of the frame.   2. The traveling wheel according to claim 1, wherein a brake device is attached to the traveling wheel, and the brake device has a cylindrical brake drum fixed to the hub, and an inner peripheral surface and an outer peripheral surface of the brake drum in a radial direction. An electric small vehicle comprising inner and outer brake shoes arranged so as to be clamped.

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