JP2004001631A - Steering wheel unit for automatically guided vehicle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a steering wheel unit for an automatically guided vehicle that can stabilize turning by allowing the floor lowering of the automatically guided vehicle even if making a wheel diameter large. <P>SOLUTION: This steering wheel unit for the automatically guided vehicle is provided with a fixed side base 22 mounted to a vehicle body; a turning side base 24 to which a wheel motor 25 with a wheel 25a is mounted; and an intersecting roller bearing 21 for supporting the turning side base 24 in a turnable manner to the fixed side base 22. A transmission mechanism is constituted by mounting a steering internal tooth gear 23 to the fixed side base 22, mounting a steering motor 26 having a steering pinion 28, to the turning side base 24, and meshing the steering internal tooth gear 23 and the steering pinion 28 with each other. The wheel 25a is steered by the rotation of the steering motor 26. In this constitution, a part (an upper part) of the wheel 25a is disposed in a position surrounded by an inner ring of the intersecting roller bearing 21. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention includes a fixed portion attached to a vehicle body, a turning portion that supports wheels, and a bearing that supports the turning portion so that the turning portion can turn with respect to the fixed portion, and a steering motor rotates the fixed portion or the turning portion. The present invention relates to a steering wheel unit for an automatic guided vehicle, which is attached to any one of the parts, and the wheel is steered by turning the turning part via a transmission mechanism by rotation of the steering motor.
[0002]
[Prior art]
Hitherto, as shown in FIGS. 13 and 14, a steering wheel unit for an automatic guided vehicle has been known. FIG. 13 is a plan view of a conventional steering wheel unit for an automatic guided vehicle. FIG. 14 is a partially broken front view of the automatic guided vehicle steering wheel unit shown in FIG.
[0003]
A conventional steering wheel unit for an automatic guided vehicle shown in FIGS. 13 and 14 is a crossed roller that supports a fixed portion attached to a vehicle body, a turning portion that supports wheels, and a turning portion that can turn with respect to the fixed portion. Bearing 1 (also referred to as a cross roller bearing). The fixed portion is constituted by a steering external gear 3 which has four bolt holes 3a for mounting on the vehicle body, and is mounted on the vehicle body of the automatic guided vehicle by bolts (not shown). The turning section includes a turning base 4, a wheel motor (drive motor with wheels 5 a) 5, wheels 5 a, a steering motor 6, a steering speed reducer 7, and a steering pinion 8. The wheel motor (drive motor with wheels 5a) 5, the steering motor 6, the steering speed reducer 7, and the steering pinion 8 are attached to the turning base 4 by appropriate means. The steering pinion 8 is connected to the steering motor 6 via a steering speed reducer 7. When the steering motor 6, the steering speed reducer 7, and the steering pinion 8 are attached to the turning base 4 by appropriate means, the steering pinion 8 is attached so as to mesh with the steering external gear 3. The crossed roller bearing 1 is disposed so as to pivotally support a turning base 4 as a turning portion with respect to a steering external gear 3 as a fixed portion, and is located above the wheels 5a.
[0004]
A conventional steering wheel unit for an automatic guided vehicle shown in FIGS. 13 and 14 is configured as described above. Therefore, when power is supplied to the wheel motor (drive motor with wheels 5a) 5, the wheels 5a rotate and the automatic guided vehicle runs. When the steering motor 6 rotates, the steering external gear 3 meshing with the steering pinion 8 is mounted on the vehicle body. The turning section including the wheel motor (drive motor with wheels 5a) 5, the steering motor 6, and the steering speed reducer 7 turns integrally. As a result, the wheel 5a is steered by a required amount. The operation of the steering motor 6 is controlled by, for example, a signal generated by an electromagnetic action between a guide sensor (not shown) and a linear conductor installed on the floor.
[0005]
Another conventional steering wheel unit for an automatic guided vehicle is disclosed in Japanese Patent Application Laid-Open No. 2000-264007, entitled "Steering Wheel Unit and Carrier with Steering Wheel Unit". FIG. 15 is a partially cutaway front view of a steering wheel unit for an automatic guided vehicle disclosed in Japanese Unexamined Patent Application Publication No. 2000-264007, “Steering Wheel Unit and Carrier with Steering Wheel Unit”.
[0006]
Another conventional automatic guided vehicle steering wheel unit shown in FIG. 15 is a crossed roller bearing that supports a fixed portion attached to a vehicle body, a turning portion that supports wheels, and a turning portion that can turn with respect to the fixed portion. (Also referred to as a cross roller bearing) 11. The fixing portion includes a fixed shaft 12 with a flange and a steering external gear 13. The flanged fixed shaft 12 has a flange attached to the vehicle body, and the steering external gear 13 is attached to the flanged fixed shaft 12. The turning section includes a turning base 14 with an outer shaft 14a, a wheel motor (drive motor with wheels 15a) 15, wheels 15a, a steering motor 16, and a steering pinion 18. The wheel motor (drive motor with wheels 15a) 15, the steering motor 16, and the steering pinion 18 are attached to the turning base 14 by appropriate means. The steering pinion 18 is connected to an output shaft 16a of the steering motor 16. When the steering motor 16 and the steering pinion 18 are attached to the turning base 14 by appropriate means, the steering pinion 18 is attached so as to mesh with the steering external gear 13. The crossed roller bearing 11 is provided between the fixed shaft 12 with the flange and the outer shaft 14a of the turning base 14 with the outer shaft 14a, and the turning base that is the turning portion with respect to the fixed shaft 12 with the flange that is the fixed portion. 14 is disposed so as to be capable of turning, and is located above the wheels 15a.
[0007]
Another conventional automatic guided vehicle steering wheel unit shown in FIG. 15 is configured as described above. Therefore, when the wheel motor (drive motor with wheels 15a) 15 is energized, the wheels 15a rotate and the automatic guided vehicle runs. When the steering motor 16 rotates, the steering external gear 13 meshing with the steering pinion 18 is attached to the vehicle body by the fixed shaft 12 with the flange, so that the steering pinion 18 moves around the outer periphery of the steering external gear 13 in a planetary motion. Then, the turning part including the turning base 14, the wheel motor (drive motor with wheels 15a) 15, and the steering motor 16 turns integrally. As a result, the wheel 15a is steered by a required amount. The operation of the steering motor 16 is also controlled by, for example, a signal generated by an electromagnetic action between a guide sensor (not shown) and a linear conductor installed on the floor.
[0008]
[Problems to be solved by the invention]
By the way, in general, it is necessary to increase the diameter of the wheel in order to improve the load-bearing capacity of the automatic guided vehicle steering wheel unit. However, in the conventional steering wheel unit for an automatic guided vehicle shown in FIGS. 13 and 14 and another conventional steering wheel unit for an automatic guided vehicle shown in FIG. The height of the vehicle steering wheel unit is increased, and as a result, the height of the automatic guided vehicle is also increased. Therefore, there is a problem that the diameter of the wheel cannot be increased in the low floor type automatic guided vehicle. Such a problem is caused by the relatively small diameter of the crossed roller bearing in the conventional automatic guided vehicle steering wheel unit shown in FIGS. 13 and 14 and another conventional automatic guided vehicle steering wheel unit shown in FIG. It is small and is due to the cross roller bearing being located above the wheel.
[0009]
Therefore, the present invention provides a steering wheel unit for an automatic guided vehicle, which solves the above-mentioned problems and can reduce the floor of the automatic guided vehicle even when the wheel diameter is increased and stabilize turning. I do.
[0010]
[Means for Solving the Problems]
In order to solve the above-mentioned problems, the invention according to claim 1 includes a fixed portion attached to a vehicle body, a turning portion that supports wheels, and a bearing that supports the turning portion to be able to turn with respect to the fixed portion. For an automatic guided vehicle in which a steering motor is attached to either the fixed part or the turning part, and the wheel is steered by turning the turning part via a transmission mechanism by rotation of the steering motor. In the steering wheel unit, a part of the wheel is disposed at a position surrounded by an inner ring of the bearing.
[0011]
According to a second aspect of the present invention, there is provided an automatic guided vehicle steering wheel unit according to the first aspect, wherein the bearing comprises a crossed roller bearing.
[0012]
According to the first and second aspects of the present invention, since a part of the wheel is disposed at a position surrounded by the inner ring of the bearing, the floor of the automatic guided vehicle can be reduced. In addition, by disposing a part of the wheel at a position surrounded by the inner ring of the bearing, the diameter of the bearing increases as a result, and the turning can be stabilized.
[0013]
According to the second aspect of the present invention, in the steering wheel unit for an automatic guided vehicle according to the first aspect, since the bearing is constituted by a crossed roller bearing, it receives an axial load, a radial load, and a moment load. Therefore, the steering wheel unit for an automatic guided vehicle can be reduced in size.
[0014]
BEST MODE FOR CARRYING OUT THE INVENTION
Embodiments of the present invention will be described below with reference to the drawings. First, a steering wheel unit for an automatic guided vehicle according to Embodiment 1 of the present invention will be described. FIG. 1 is a plan view of a steering wheel unit for an automatic guided vehicle according to Embodiment 1 of the present invention. FIG. 2 is a front view of the automatic guided vehicle steering wheel unit shown in FIG. FIG. 3 is a sectional view taken along line AA in FIG. FIG. 4 is a perspective view of the automatic guided vehicle steering wheel unit shown in FIG.
[0015]
A steering wheel unit for an automatic guided vehicle according to Embodiment 1 of the present invention includes a fixed portion attached to a vehicle body, a turning portion on which wheels are supported, and a bearing for supporting the turning portion to be able to turn with respect to the fixed portion. It has. The bearing is composed of a cross roller bearing (also referred to as a cross roller bearing) 21. The cross roller bearing 21 is an angular contact bearing having one row of rollers arranged so that adjacent rollers cross each other. In this crossed roller bearing 21, the axial load in one direction is supported by every other roller of the roller set, the axial load in the opposite direction is supported by the other half of the roller set, and the radial load and moment load are also one. Can be received in one bearing.
[0016]
The fixed portion includes a fixed-side base 22 attached to the vehicle body and a steering internal gear 23. The steering internal gear 23 is attached to the fixed base 22 by bolts 31 '.
[0017]
The turning section includes a turning-side base 24, a wheel motor (drive motor with wheels 25a) 25, wheels 25a, a steering motor 26, a steering speed reducer 27, and a steering pinion 28. The wheel motor (drive motor with wheels 25 a) 25 is attached to the turning base 24 by bolts 31. The steering motor 26, the steering speed reducer 27, and the steering pinion 28 are attached to the turning base 24 by appropriate means. The steering pinion 28 is connected to a steering motor 26 via a steering speed reducer 27.
[0018]
When the steering motor 26, the steering speed reducer 27, and the steering pinion 28 are mounted on the turning base 24 by appropriate means, the steering pinion 28 is mounted so as to mesh with the steering internal gear 23. The transmission mechanism is constituted by the steering pinion 28 and the steering internal gear 23.
[0019]
The crossed roller bearing 21 has an inside diameter large enough to surround a part (upper part) of the wheel 25a attached to the wheel motor (drive motor with the wheel 25a) 25. The crossed roller bearing 21 is disposed between the fixed-side base 22 and the turning-side base 24, and the inner ring thereof is fixed to the turning-side base 24 by fixing the inner-ring holding ring 21a to the turning-side base 24 by appropriate means. The outer ring is attached to the fixed base 22 by fixing the outer ring pressing ring 21b to the fixed base 22 with bolts 31 ″.
[0020]
When the wheel motor (drive motor with wheels 25 a) 25 is attached to the turning base 24 by the bolts 31, a part (upper part) of the wheels 25 a is arranged at a position surrounded by the inner ring of the cross roller bearing 21.
[0021]
The steering wheel unit for an automatic guided vehicle according to Embodiment 1 of the present invention is configured as described above. Therefore, when the wheel motor (drive motor with wheels 25a) 25 is energized, the wheels 25a rotate and the automatic guided vehicle runs. When the steering motor 26 rotates, the steering internal gear 23 meshing with the steering pinion 28 is attached to the fixed side base 22, so that the steering pinion 28 planetary moves around the inner periphery of the steering internal gear 23, A turning section including the turning base 24, a wheel motor (drive motor with wheels 25a) 25, a steering motor 26, and a steering speed reducer 27 turns integrally. As a result, the wheels 25a are steered by the required amount. The operation of the steering motor 26 is controlled, for example, by a signal generated by an electromagnetic action between a guide sensor (not shown) and a linear conductor installed on the floor.
[0022]
According to the automatic guided vehicle steering wheel unit according to Embodiment 1 of the present invention, a part (upper part) of wheel 25a is arranged at a position surrounded by the inner ring of cross roller bearing 21. The floor of the automatic guided vehicle can be reduced. In addition, by disposing a part (upper part) of the wheel 25a at a position surrounded by the inner ring of the crossed roller bearing 21, the diameter of the crossed roller bearing 21 is eventually increased, and the turning can be stabilized. Furthermore, the crossed roller bearing 21 can receive an axial load, a radial load, and a moment load, and the steering wheel unit for an automatic guided vehicle can be reduced in size.
[0023]
Next, a steering wheel unit for an automatic guided vehicle according to Embodiment 2 of the present invention will be described. FIG. 5 is a plan view of a steering wheel unit for an automatic guided vehicle according to Embodiment 2 of the present invention. FIG. 6 is a front view of the steering wheel unit for the automatic guided vehicle shown in FIG. FIG. 7 is a sectional view taken along line AA in FIG. FIG. 8 is a perspective view of the steering wheel unit for the automatic guided vehicle shown in FIG.
[0024]
A steering wheel unit for an automatic guided vehicle according to a second embodiment of the present invention includes a fixed portion attached to a vehicle body, a turning portion that supports wheels, and a bearing that supports the turning portion to be able to turn with respect to the fixed portion. It has. The bearing is composed of a cross roller bearing (also referred to as a cross roller bearing) 21.
[0025]
The fixed portion includes a fixed base 22 attached to the vehicle body and a steering external gear 23 '. The steering external gear 23 'is attached to the fixed base 22 by an appropriate means.
[0026]
The turning section includes a turning-side base 24, a wheel motor (drive motor with wheels 25a) 25, wheels 25a, a steering motor 26, a steering speed reducer 27, and a steering pinion 28. The wheel motor (drive motor with wheels 25 a) 25 is attached to the turning base 24 by bolts 31. The steering motor 26, the steering speed reducer 27, and the steering pinion 28 are attached to the turning base 24 by appropriate means. The steering pinion 28 is connected to a steering motor 26 via a steering speed reducer 27.
[0027]
When the steering motor 26, the steering speed reducer 27, and the steering pinion 28 are mounted on the turning base 24 by appropriate means, the steering pinion 28 is mounted so as to mesh with the steering external gear 23 '. The transmission mechanism is constituted by the steering pinion 28 and the steering external gear 23 '.
[0028]
The crossed roller bearing 21 has an inside diameter large enough to surround a part (upper part) of the wheel 25a attached to the wheel motor (drive motor with the wheel 25a) 25. The crossed roller bearing 21 is disposed between the fixed-side base 22 and the turning-side base 24, and its inner ring is fixed to the turning-side base 24 by the inner ring holding ring 21'a with a bolt 31 '. The outer ring is attached to the fixed base 22 by fixing the outer ring holding ring 21b to the fixed base 22 with bolts 31 ".
[0029]
When the wheel motor (drive motor with wheels 25 a) 25 is attached to the turning base 24 by the bolts 31, a part (upper part) of the wheels 25 a is arranged at a position surrounded by the inner ring of the cross roller bearing 21.
[0030]
The automatic guided vehicle steering wheel unit according to Embodiment 2 of the present invention is configured as described above. Therefore, when the wheel motor (drive motor with wheels 25a) 25 is energized, the wheels 25a rotate and the automatic guided vehicle runs. When the steering motor 26 rotates, the steering external gear 23 'meshing with the steering pinion 28 is attached to the fixed side base 22, so that the steering pinion 28 planetary moves around the outer periphery of the steering external gear 23'. The turning portion including the turning base 24, the wheel motor (drive motor with wheels 25a) 25, the steering motor 26, and the steering speed reducer 27 turns integrally. As a result, the wheels 25a are steered by the required amount. The operation of the steering motor 26 is controlled, for example, by a signal generated by an electromagnetic action between a guide sensor (not shown) and a linear conductor installed on the floor.
[0031]
According to the automatic guided vehicle steering wheel unit according to the second embodiment of the present invention, the same effects as those of the automatic guided vehicle steering wheel unit according to the first embodiment of the present invention can be obtained.
[0032]
Next, a steering wheel unit for an automatic guided vehicle according to Embodiment 3 of the present invention will be described. FIG. 9 is a plan view of a steering wheel unit for an automatic guided vehicle according to Embodiment 3 of the present invention. FIG. 10 is a front view of the automatic guided vehicle steering wheel unit shown in FIG. FIG. 11 is a sectional view taken along line AA in FIG. FIG. 12 is a perspective view of the automatic guided vehicle steering wheel unit shown in FIG.
[0033]
An automatic guided vehicle steering wheel unit according to Embodiment 3 of the present invention includes a fixed portion attached to a vehicle body, a turning portion on which wheels are supported, and a bearing for rotatably supporting the turning portion with respect to the fixed portion. It has. The bearing is composed of a cross roller bearing (also referred to as a cross roller bearing) 21.
[0034]
The fixed portion includes a fixed base 22 attached to the vehicle body, a steering motor 26, a speed reducer 27 for steering, and a steering pinion 28. The steering motor 26, the steering speed reducer 27, and the steering pinion 28 are attached to the fixed base 22 by appropriate means. The steering pinion 28 is connected to a steering motor 26 via a steering speed reducer 27.
[0035]
The turning section includes a turning-side base 24, a semicircular steering external gear 23 ", a wheel motor (drive motor with wheels 25a) 25, and wheels 25a. The wheel motor (drive motor with wheels 25 a) 25 is attached to the turning base 24 by bolts 31 ′.
[0036]
When the steering motor 26, the steering speed reducer 27, and the steering pinion 28 are mounted on the fixed base 22 by appropriate means, the steering pinion 28 is mounted so as to mesh with the semicircular steering external gear 23 ". , A transmission mechanism is constituted by the steering pinion 28 and the semicircular steering external gear 23 ″.
[0037]
The crossed roller bearing 21 has a sufficient inner diameter to surround a part (upper part) of the wheel 25a attached to the wheel motor (drive motor with the wheel 25a) 25. The crossed roller bearing 21 is disposed between the fixed-side base 22 and the turning-side base 24. The inner ring of the cross-roller bearing 21 is turned by fixing the semicircular steering external gear 23 "to the turning-side base 24 with bolts 31 '. The outer ring is attached to the fixed base 22 by fixing the outer ring holding ring 21b to the fixed base 22 with bolts 31 ".
[0038]
When the wheel motor (drive motor with wheels 25 a) 25 is attached to the turning base 24 by the bolts 31, a part (upper part) of the wheels 25 a is arranged at a position surrounded by the inner ring of the cross roller bearing 21.
[0039]
The steering wheel unit for an automatic guided vehicle according to the third embodiment of the present invention is configured as described above. Therefore, when the wheel motor (drive motor with wheels 25a) 25 is energized, the wheels 25a rotate and the automatic guided vehicle runs. When the steering motor 26 rotates, the steering pinion 28 is attached to the fixed base 22 together with the steering motor 26 and the steering speed reducer 27. Therefore, the semicircular steering external gear 23 '' meshing with the steering pinion 28 is The vehicle is turned by the steering pinion 28, and the turning portion including the turning base 24 and the wheel motor (drive motor with wheels 25a) 25 turns integrally, so that the wheels 25a are steered by a required amount. The operation control of the motor 26 is performed by, for example, a signal generated by an electromagnetic action between a guide sensor (not shown) and a linear conductor installed on the floor surface. In the steering wheel unit, the steering wheel Although the semi-circular steering external gear 23 "is used as the external gear meshing with the nonion 28, the external gear is not limited to the semi-circular steering external gear 23", and a modification thereof (not shown) An annular or circular steering external gear may be used.
[0040]
According to the automatic guided vehicle steering wheel unit according to the third embodiment of the present invention and its modification, the same effect as that of the automatic guided vehicle steering wheel unit according to the first embodiment of the present invention is exerted.
[0041]
In each of the embodiments of the present invention, the crossed roller bearing 21 is used as a bearing. However, in the invention described in claim 1, the invention is not limited to the crossed roller bearing, and may be replaced with a crossed roller bearing. Thus, a four-point contact ball bearing or other bearings can be used.
[0042]
In each of the embodiments of the present invention, the case where the wheel 25a is a driving wheel is described. However, it is needless to say that the present invention can be applied to a case where the wheel is a driven wheel.
[0043]
Further, the automatic guided vehicle referred to in the present invention is used in a broad sense including an unmanned tow truck and an unmanned forklift, and the present invention includes a steering wheel unit for an unmanned tow truck or a steering wheel unit for an unmanned forklift.
[0044]
【The invention's effect】
According to the first and second aspects of the present invention, the floor of the automatic guided vehicle can be reduced by arranging a part of the wheel at a position surrounded by the inner ring of the bearing. In addition, by disposing a part of the wheel at a position surrounded by the inner ring of the bearing, the diameter of the bearing increases as a result, and the turning can be stabilized.
[0045]
According to a second aspect of the present invention, in the first aspect of the invention, since the bearing is constituted by a crossed roller bearing, the bearing can receive an axial load, a radial load, and a moment load, and is a steering wheel for an automatic guided vehicle. The unit can be reduced in size.
[Brief description of the drawings]
FIG. 1 is a plan view of a steering wheel unit for an automatic guided vehicle according to Embodiment 1 of the present invention.
FIG. 2 is a front view of the automatic guided vehicle steering wheel unit shown in FIG. 1;
FIG. 3 is a sectional view taken along line AA in FIG.
4 is a perspective view of the automatic guided vehicle steering wheel unit shown in FIG. 1;
FIG. 5 is a plan view of a steering wheel unit for an automatic guided vehicle according to Embodiment 2 of the present invention.
6 is a front view of the automatic guided vehicle steering wheel unit shown in FIG. 5;
FIG. 7 is a sectional view taken along line AA in FIG.
8 is a perspective view of the steering wheel unit for an automatic guided vehicle shown in FIG. 5;
FIG. 9 is a plan view of a steering wheel unit for an automatic guided vehicle according to Embodiment 3 of the present invention.
FIG. 10 is a front view of the automatic guided vehicle steering wheel unit shown in FIG. 9;
FIG. 11 is a sectional view taken along line AA in FIG. 9;
12 is a perspective view of the automatic guided vehicle steering wheel unit shown in FIG. 9;
FIG. 13 is a plan view of a conventional automatic guided vehicle steering wheel unit.
14 is a partially cutaway front view of the automatic guided vehicle steering wheel unit shown in FIG. 13;
FIG. 15 is a partially cutaway front view of another conventional automatic guided vehicle steering wheel unit.
[Explanation of symbols]
21 Crossed Roller Bearings 21a, 21'a Inner Ring Holding Ring 21b Outer Ring Holding Ring 22 Fixed Side Base 23 Steering Internal Gear 23 'Steering External Gear 23 "Semicircular Steering External Gear 24 Turning Base 25 Wheel Motor 25a Wheel 26 Steering Motor 27 Steering reducer 28 Steering pinion 31 Bolt 31 'Bolt 31 "Bolt

Claims (2)

A fixed portion attached to the vehicle body, a turning portion for supporting wheels, and a bearing for supporting the turning portion to be able to turn with respect to the fixed portion, wherein a steering motor is provided for either the fixed portion or the turning portion. The steering wheel unit for an automatic guided vehicle, wherein the wheels are steered by the turning portion being turned via a transmission mechanism by the rotation of the steering motor,
A steering wheel unit for an automatic guided vehicle, wherein a part of the wheel is disposed at a position surrounded by an inner ring of the bearing. The steering wheel unit for an automatic guided vehicle according to claim 1, wherein the bearing is formed of a crossed roller bearing.

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