Technical Field
[0001] The present invention relates to a railway vehicle such as a railroad vehicle, a
monorail vehicle, or a new transportation system vehicle, and particularly relates
to a railway vehicle equipped with a virtual center plate method traction device and
a truck capable of promoting reduction in a size and a weight.
Background Art
[0002] Not only in a railroad vehicle but also in a railway vehicle such as a monorail vehicle
or a new transportation system vehicle, a vehicle body is connected to a truck through
a support device and a traction device. The support device mainly supports a weight
of the vehicle body, and includes an air spring disposed on an upper surface of a
truck frame and the like. The traction device transmits a force in a forward and backward
direction such as a driving force or a braking force from the truck to the vehicle
body, and turns the truck around a vertical axis at a central portion of the truck.
The traction device includes a center pin extending vertically downward from a lower
surface of the vehicle body at both ends thereof in a longitudinal direction thereof,
a link connecting the center pin to a central portion of the truck frame, and the
like.
[0003] Generally, in a vehicle requiring to dispose an actuator at a central portion of
a truck, such as a diesel vehicle in which a propeller shaft extending from an internal
combustion engine disposed on a lower surface of a vehicle penetrates through a central
portion of a truck in a forward and backward direction, a pendulum vehicle in which
a mechanism such as a pendulum beam, a roller, or a pendulum control actuator is integrated
in a central portion of a truck, or a vehicle for supporting a vehicle body with one
air spring per truck, it may be difficult to dispose a traction device at a central
portion of a truck. PTL 1 discloses a traction device applied to a three-axis truck
for a locomotive in which it is difficult to dispose a traction device at a central
portion of the truck similarly to the above vehicle.
[0004] The traction device disclosed in PTL 1 includes a center plate seat, a center plate,
and a center plate metal fitting (right angle crank) disposed sequentially downward
from a lower surface of a portion near a center of a truck on left and right side
beams of a truck frame, a vertical movement metal fitting connected to an outside
of the center plate metal fitting in a sleeper direction through a link, a link shaft
(link) for connecting a pair of center plate metal fittings disposed on the left and
the right of the truck frame, and a V-shape link (draw shaft) for connecting both
ends of the vertical movement metal fitting in a rail direction to link receivers
disposed on a lower surface of an underframe of a vehicle body along the rail direction.
[0005] The center plate metal fitting (right angle crank) can be rotated around a vertical
axis of the center plate. The link shaft synchronizes rotational displacements of
the center plate metal fittings on the left and the right of the truck frame due to
planar motion. Rotational displacements generated in the center plate metal fittings
(right angle cranks) on the left and the right of the truck frame are restrained by
the link shaft. Therefore, a force in a forward and backward direction such as a driving
force of the truck or a braking force thereof is transmitted to the vehicle body via
a draw shaft connected to the vertical movement metal fitting through the center plates
(pins) and the center plate metal fittings on the left and the right of the truck
frame.
[0006] When the traction device passes through a curve, the center plate metal fittings
(right angle cranks) on the left and the right of the truck frame are rotated using
the center plates (pins) as vertical axes in accordance with a turning action of the
truck along the curve, and the link (link shaft) rotates the center plate metal fittings
on the left and the right in the same direction. Forces of compression and tension
thereby act on each of the pair of draw shafts on the left and the right of the truck
frame. Due to this action, the truck turns around a virtual center plate as if a virtual
center plate (a member acting as a turning center of the truck) is present at the
central portion of the truck frame (virtual center plate method). The traction device
described in PTL 1 includes a part constituting the traction device, such as a center
plate metal fitting or a draw shaft, below the truck (at a position close to a rail
upper surface) in order to realize an axle weight compensation function.
Citation List
Patent Literature
Summary of Invention
Technical Problem
[0008] Conventionally, a link shaft (link) constituting a virtual center plate method traction
device has been disposed along a sleeper direction at a position offset from a central
portion of a truck in a longitudinal (rail) direction thereof in the longitudinal
direction. Therefore, it is necessary to make a design to avoid interference between
the link shaft and a part such as a main motor receiver at the central portion of
the truck. For example, a size of the truck in the longitudinal direction thereof
is increased by the offset of the link shaft. This may be one of factors for inhibiting
reduction in a size of the truck and a weight thereof.
[0009] In addition, there is a problem to be solved in terms of improving maintainability.
For example, when the link shaft or the draw shaft is disposed near the rail upper
surface below the truck frame, it may be necessary to inspect these parts due to an
impact of ballast that snow which has arrived at a lower surface of the truck is scattered
by falling snow during travelling in winter.
[0010] The present invention has been achieved in view of this problem, and provides a traction
device for a railway vehicle capable of reducing a size of a virtual center plate
method truck and a weight thereof by reducing a size of the truck in a longitudinal
direction thereof and improving maintainability in a railway vehicle equipped with
the truck.
Solution to Problem
[0011] The above problem can be solved by the following characteristics of a railway vehicle
of the present invention. That is, in the railway vehicle of the present invention,
a vehicle is connected to a truck through a traction device. This traction device
includes a link shaft disposed at a central portion of the truck in a longitudinal
direction thereof along a width direction thereof, link shaft arms disposed at both
ends of the link shaft, and draw shafts for connecting the link shaft arms to a vehicle
body and disposed along a longitudinal direction of the vehicle body. One end of one
of the link shaft arms is connected to one end of the link shaft. One of the draw
shafts is connected to the other end of the one of the link shaft arms extending downward,
and is disposed toward one end of the vehicle in a longitudinal direction thereof.
One end of the other of the link shaft arms is connected to the other end of the link
shaft. The other of the draw shafts is connected to the other end of the other of
the link shaft arms extending upward, and is disposed toward the other end of the
vehicle in a longitudinal direction thereof.
Advantageous Effects of Invention
[0012] The present invention can provide a traction device for a railway vehicle capable
of reducing a size of a virtual center plate method truck and a weight thereof by
reducing a size of the truck in a longitudinal direction thereof and improving maintainability
in a railway vehicle equipped with the truck.
Brief Description of Drawings
[0013]
[FIG. 1] FIG. 1 is a side view of a railroad vehicle.
[FIG. 2] FIG. 2 is a side view of a truck indicated by A part in FIG. 1.
[FIG. 3] FIG. 3 is a plan view of a truck illustrated in FIG. 2.
[FIG. 4] FIG. 4 is a perspective view for explaining an action of a traction device
when the vehicle illustrated in FIGS. 1 to 3 accelerates.
[FIG. 5] FIG. 5 is a perspective view for explaining an action of the traction device
when the vehicle illustrated in FIGS. 1 to 3 passes through a curve.
[FIG. 6] FIG. 6 is a side view of a truck of a vehicle in Example 2.
[FIG. 7] FIG. 7 is a side view of a truck of a monorail vehicle in Example 3, to which
the traction device illustrated in FIGS. 2 to 6 is applied.
[FIG. 8] FIG. 8 is a plan view of the truck of a monorail vehicle illustrated in FIG.
7.
Description of Embodiments
[0014] Hereinafter, embodiments of the present invention will be described with reference
to FIGS. 1 to 8. Before the present invention is described, directions will be defined.
The directions are a longitudinal direction (forward and backward direction) of a
railway vehicle or a truck or a rail direction 100, a width (lateral) direction of
the railway vehicle or the truck or a sleeper direction 110, and a height direction
120. These directions are simply referred to as a longitudinal direction (forward
and backward direction) 100, a width (lateral) direction 110, and a height (vertical)
direction 120.
[0015] The railway vehicle is a vehicle travelling along a laid track, and includes a railroad
vehicle, a monorail vehicle, a new transportation vehicle, a tram, and the like. In
Examples of the present invention, as a representative of the railway vehicle, the
railroad vehicle and the monorail vehicle will be exemplified, but the railway vehicle
can be also applied to a truck of the new transportation vehicle, the tram, or the
like.
[Example 1]
[0016] FIG. 1 is a side view of a railroad vehicle. FIG. 2 is a side view of a truck of
a vehicle indicated by A part in FIG. 1. FIG. 3 is a plan view of a truck illustrated
in FIG. 2. A truck 12 includes a truck frame 70 and a wheel shaft 32 obtained by connecting
two wheels 31 through an axle 30. The truck frame 70 includes two side beams 71 disposed
apart from each other along the longitudinal direction 110 and a transverse beam 72
for connecting center portions of the side beams 71 in the longitudinal direction
to each other, and is a substantially H-shaped part when being overlooked. In FIG.
3, the two transverse beams 72 connect the side beams 71 to each other, but one transverse
beam 72 may connect the side beams 71 to each other. The wheel shaft 32 rolling on
a rail 1 is obtained by connecting the two wheels 31 through the axle 30, and is rollably
held by axle boxes 34 disposed at both ends of the wheel shaft 32. The axle boxes
34 support both ends of each of the side beams 71 in the longitudinal direction via
a shaft spring 33 disposed on each of the axle boxes 34.
[0017] A vehicle body 11 is connected to the truck 12 via a vehicle body support device
40. The vehicle body support device 40 includes an air spring 46 for supporting a
load of the vehicle body in a vertical direction and a traction device 20 for transmitting
a driving force or a braking force (force acting in the forward and backward direction
100) of the truck 12 to the vehicle body 11.
[0018] The traction device 20 includes a link shaft 21 disposed at a central portion of
the truck 12 in the longitudinal direction 100 along the width direction 110, a link
shaft arm 22 one end of which is connected to one end of the link shaft 21, a draw
shaft 23 one end of which is connected to the other end of the link shaft arm 22,
and a draw shaft bracket 25 for connecting the other end of the draw shaft 23 to the
vehicle body 11.
[0019] Both ends of the link shaft 21 are disposed rotatably to a pair of link shaft brackets
24 disposed on an upper surface of the truck frame 70 (side beams 71 on the left and
the right) . Between the link shaft 21 and each of the link shaft brackets 24, a bearing
structure reducing friction and wear by a self-lubricating function such as OILES
(registered trademark) and capable of withstanding a force in the forward and backward
direction (radial load) from the truck 12 is desirable. The link shaft brackets 24
may be omitted, and the link shaft 21 may be disposed by opening a hole on a side
surface of the side beam 71 between the two transverse beams 72 and disposing the
above-described bearing structure in this hole. Furthermore, when only one hollow
transverse beam 72 is disposed, the link shaft 21 may be disposed at a center line
(at an axis in a case of a cylinder) of the transverse beam 72 in a longitudinal direction
thereof (width direction 110).
[0020] A pair of the link shaft arms 22 disposed along the height direction 120 is connected
to both ends of the link shaft 21. One link shaft arm 22a (refer to FIG. 4) is disposed
such that an upper end thereof is connected to one end of the link shaft 21, and a
lower end thereof extends downward. The other link shaft arm 22b (refer to FIG. 4)
is disposed such that a lower end thereof is connected to the other end of the link
shaft 21, and an upper end thereof extends upward. The link shaft arm 22 is disposed
along the height direction 120, but may be disposed not only in the vertical direction
but also in such a manner that the link shaft arm 22 is inclined in the longitudinal
direction 100. The link shaft arms 22 on the left and the right have the same size
in the height direction. The link shaft arms 22 and the link shaft 21 have an integral
structure in which the link shaft arms 22 and the link shaft 21 are connected to each
other by welding, press fitting, or the like.
[0021] A lower end of the one link shaft arm 22a is connected to a draw shaft bracket 25a
(refer to FIG. 4) disposed at one end of a lower surface of the vehicle body 11 in
the width direction 110 through a draw shaft 23a. An upper end of the other link shaft
arm 22b is connected to a draw shaft bracket 25b (refer to FIG. 4) disposed at the
other end of the lower surface of the vehicle body 11 in the width direction 110 through
a draw shaft 23b. The one draw shaft 23a is disposed from the lower end of the link
shaft arm 22a toward one end of the vehicle in the longitudinal direction 100. The
other draw shaft 23b is disposed from the upper end of the link shaft arm 22b toward
the other end of the vehicle in the longitudinal direction 100.
[0022] A bearing having a rotational degree of freedom around the lateral direction 110
as an axis may be disposed at one end of the draw shaft 23, and a bearing having a
rotational degree of freedom around the vertical direction 120 as an axis may be disposed
at the other end of the draw shaft 23 such that relative lateral and vertical displacements
are allowable between the vehicle body and the truck. In order to reduce transmission
of vibration from the truck 12 to the vehicle body 11 caused by track irregularity
or the like, a spherical bearing capable of allowing displacements in the lateral
direction 110 and the vertical direction 120 or an elastic body such as a rubber bush
may be disposed at both ends of the draw shaft 23.
[0023] FIG. 4 is a perspective view for explaining an action of the traction device when
the vehicle accelerates. The arrows indicated in the vehicle body 11, the draw shafts
23a and 23b, the link shaft arms 22a and 22b, and the link shaft brackets 24a and
24b illustrated in FIG. 4 indicate forces acting on parts constituting the traction
device when a vehicle 10 accelerates.
[0024] The vehicle 10 accelerates in such a manner that a driving force generated by rolling
of the wheel shaft 32 driven by a main motor (not illustrated) mounted on the truck
12 on the rail 1 pulls or propels the vehicle body 11 via the traction device (draw
shaft). At this time, forces A having the same magnitude and the same direction are
transmitted to the draw shaft 23a as a pulling force (tensile force) and the draw
shaft 23b as a propulsion force (compression force).
[0025] A moment force acts on the link shaft 21 by the force A transmitted to each of the
draw shafts 23a and 23b and the link shaft arms 22a and 22b. A moment force in a direction
of an arrow B acts on one end of the link shaft 21. A moment force in a direction
of an arrow C acts on the other end of the link shaft 21. A direction in which a moment
force acts on one end of the link shaft 21 is opposite (reverse) to a direction in
which a moment force acts on the other end of the link shaft 21.
[0026] The link shaft arms 22a and 22b are connected to both ends of the link shaft 21 integrally.
Therefore, the moment forces acting on both ends of the link shaft 21 in opposite
directions are cancelled. Due to the cancellation of the moment forces, the link shaft
arms 22a and 22b do not make a rotational displacement, and the force A acting on
the draw shafts 23a and 23b is directly transmitted to the vehicle body 11 via the
draw shaft brackets 25a and 25b. By such a balance of the driving forces and such
an action, the vehicle 10 continues to accelerate in a forward direction. When the
truck 12 generates a braking force, a translational force or a moment force is generated
in a direction opposite to the case where the above driving force is generated, and
the vehicle 10 decelerates.
[0027] FIG. 5 is a perspective view for explaining an action of the traction device when
the vehicle illustrated in FIGS. 1 to 3 passes through a curve. FIG. 5 illustrates
a state when the truck 12 yaws (turns) in a direction of an arrow D with respect to
the vehicle body 11 and the vehicle 10 passes through a left curve. In FIG. 5, a two-dot
chain line indicates states of the vehicle body and the truck when the vehicle 10
travels straight, and a solid line indicates states thereof when the vehicle 10 passes
through a curve. The arrows illustrated in the vehicle body 11, the draw shafts 23a
and 23b, and the link shaft arms 22a and 22b indicate forces acting on parts constituting
the traction device when the truck 12 yaws in the direction of the arrow D with respect
to the vehicle body 11. An arrow E illustrated on a front side of the truck 12 indicates
a traveling direction of the vehicle 10 passing through a left curve, and the arrow
D illustrated at the central portion of the truck 12 indicates a direction in which
the truck 12 yaws with respect to the vehicle body 11.
[0028] First, when the truck 12 yaws in the direction of the arrow D with respect to the
vehicle body 11, a force F acts on the link shaft arm 22a from the draw shaft 23a,
and a force G acts on the link shaft arm 22b from the draw shaft 23b. The link shaft
arm 22a and 22b are rotated in a vertical plane by these forces F and G to generate
moment forces H in the same direction at both ends of the link shaft 21. At this time,
the link shaft arm 22a is connected to the draw shaft 23a, and the link shaft arm
22b is connected to the draw shaft 23b. Therefore, one end of the link shaft 21 (a
side of the link shaft arm 22a) integrated with the link shaft arm 22 is displaced
in a direction of an arrow J, and the other end of the link shaft 21 (a side of the
link shaft arm 22b) is displaced in a direction of an arrow I.
[0029] As a result, the link shaft 21 makes a yawing displacement (turns) in the direction
of the arrow D in a horizontal plane around the central portion in the longitudinal
direction (width direction 110) thereof. The link shaft 21 is fixed to the truck frame
70 via the link shaft brackets 24a and 24b. Therefore, the truck 12 is displaced in
accordance with the yawing motion of the link shaft 21, and makes a yawing displacement
in the direction of the arrow D around a vertical axis at a central portion of the
truck 12 with respect to the vehicle body 11 as if a center plate is present.
[0030] In a traction device realizing a conventional virtual center plate method, including
a link shaft, a right angle crank, and the like, the right angle crank or the like
moves in a horizontal plane, and therefore a compression load and a tensile load act
on the link shaft. Meanwhile, in the link shaft 21 included in the traction device
according to the present invention, when a vehicle accelerates or decelerates and
passes through a curve (when a truck turns), a compression load or a tensile load
is not generated in an axis direction of the link shaft 21, and only a torsional (moment)
load acts on the link shaft 21. Therefore, by forming the link shaft 21 with a cylindrical
member robust with respect to a torsional load, reduction in weights of the traction
device and the truck can be promoted.
[0031] Due to the above structure, a railway vehicle equipped with the above traction device,
such as a diesel vehicle in which a propeller shaft penetrates through a central portion
of a truck in a forward and backward direction, a pendulum vehicle in which a mechanism
such as a pendulum beam, a roller, or a pendulum control actuator is integrated in
a central portion of a truck, or a vehicle for supporting a vehicle body with one
air spring per truck, can be provided in place of a conventional traction device with
a central pin.
[0032] In addition, in the conventional virtual center plate method traction device, a link
shaft is connected to a right angle crank making a rotational displacement around
a vertical axis, and performs a planar motion on an upper surface of a truck frame
(a transverse beam or a side beam). Therefore, the link shaft is disposed at a position
offset from a central portion of a truck in a longitudinal direction thereof. Therefore,
in order to avoid interference between the link shaft and a part such as a wheel,
the central portion of the truck requires a length of at least the offset in a longitudinal
direction of a vehicle.
[0033] Meanwhile, in the traction device of the present invention, the link shaft is rotated
around a lateral direction of the vehicle as an axis, and the link shaft can be thereby
disposed at the central portion of the truck without providing an offset in the longitudinal
direction of the vehicle. That is, the length of the truck in the longitudinal direction
of the vehicle, required for avoiding interference between the link shaft and a part
such as a wheel, can be reduced, and a railway vehicle equipped with the truck promoting
reduction in a size and a weight can be provided.
[0034] In Examples of the present invention, the link shaft is disposed so as to be connected
to the side beams on the left and the right between the transverse beams disposed
apart from each other along the longitudinal direction 100, but may be disposed on
an upper surface of the truck frame. In addition, the link shaft bracket may be connected
to the vehicle body, and the draw shaft bracket may be connected to the truck. Furthermore,
by forming a suspension device above the upper surface of the truck frame, an impact
of ballast due to falling snow or the like on the traction device can be avoided.
Therefore, an increase in maintenance cost of the traction device can be suppressed.
[0035] In a conventional steering truck, a vehicle body is connected to a truck, and the
truck is connected to a wheel shaft through a plurality of links, and the links are
driven in accordance with relative yawing of the vehicle and the truck caused when
the truck passes through a curve. The steering truck steers the wheel shaft such that
the wheel shaft is directed to a radial direction of the curve, and does not have
a function of turning the truck around a vertical axis of the central portion thereof.
Meanwhile, in the traction device of the present invention, the vehicle body is connected
to the truck through the link shaft, the draw shaft, or the like, the link shaft makes
a rotational displacement in accordance with relative yawing of the vehicle and the
truck caused when the traction device passes through a curve, and the truck yaws around
a vertical axis of the central portion thereof with respect to the vehicle body. The
conventional steering truck is largely different from the present invention in a structure
thereof and an effect in accordance with an action thereof.
[Example 2]
[0036] FIG. 6 is a side view of a truck of a vehicle in Example 2. The same reference sign
is given to a part having a common or similar effect to a part constituting the traction
device illustrated in FIGS. 1 to 5 and a railroad vehicle including the traction device.
Only a part and a structure different from those in FIGS. 1 to 5 will be described.
[0037] Two link shaft arms 22 of a traction device 20 illustrated in FIG. 6 are disposed
at both ends of a link shaft 21 along a height direction. One link shaft arm 22a is
integrally connected to an end of the link shaft 21 at a central portion in a longitudinal
direction thereof by welding or the like. A draw shaft 23a is connected to one end
of the link shaft arm 22a extending downward, and one end of a yaw damper 26a is connected
to the other end thereof extending upward. The other end of the yaw damper 26a is
connected to a yaw damper bracket 27a disposed on a side surface of a side beam 71
forming a truck frame 70.
[0038] The other link shaft arm 22b is integrally connected to an end of the link shaft
21 at a central portion in a longitudinal direction thereof by welding or the like.
A draw shaft 23b (not illustrated) is connected to one end of the link shaft arm 22b
extending upward, and one end of a yaw damper 26b (not illustrated) is connected to
the other end thereof extending downward. The other end of the yaw damper 26b is connected
to a yaw damper bracket 27b (not illustrated) disposed on a side surface of the side
beam 71 forming the truck frame 70.
[0039] This yaw damper 26 includes a piston, a cylinder, an adjusting valve, a relief valve,
and the like. The cylinder is filled with oil. As described in Example 1, when a relative
yawing motion occurs in a vehicle body 11 and a truck 12, for example, when a vehicle
10 passes through a curve, the link shaft arm 22 makes a rotational displacement around
a lateral direction 110 as an axis together with the link shaft 21. When the link
shaft arm 22 makes a rotational displacement counter-clockwise around the lateral
direction 110 as an axis, a piston of the yaw damper 26 is displaced in a stretching
direction with respect to a cylinder. On the contrary, when the link shaft arm 22
makes a rotational displacement clockwise around the lateral direction 110 as an axis,
the piston is displaced in a contracting direction with respect to the cylinder.
[0040] The oil in the cylinder passes through the adjusting valve or the relief valve in
the cylinder in accordance with the stretching and contracting motion of the piston,
a damping force is thereby generated in the yaw damper 26. This damping force attenuates
a rotational displacement of the link shaft arm 22 and a back and forth displacement
of the draw shaft 23 in accordance with the rotational displacement of the link shaft
arm 22, attenuates a displacement of a mechanism connected to the draw shaft 23, the
link shaft arm 22, and the link shaft 21, and thereby attenuates yawing of the truck
12 with respect to the vehicle body 11.
[0041] The higher the stretching and contracting speed of the piston is, the larger the
damping force of the yaw damper 26 is. Therefore, a large damping force is not generated
with respect to a slow yawing motion when the vehicle 10 passes through a curve, and
a large damping force is generated with respect to a fast yawing motion such as a
snake behavior generated when the vehicle 10 travels at a high speed. As another method
to form the yaw damper 26, a rotary damper to attenuate a rotational motion of the
link shaft 21 or the like may be formed between the link shaft 21 and the truck frame
70 to attenuate the relative yawing motion of the vehicle body 11 and the truck 12.
[0042] In Example 2, a yaw damper for attenuating a relative yawing motion of a vehicle
body and a truck is added to the structure of Example 1. Example 2 thereby can suppress
self-excited vibration called a snake behavior by which the vehicle body or the truck
swings violently to the left and the right when the vehicle travels at a high speed,
and improves travelling stability of the vehicle in addition to the effect of Example
1.
[Example 3]
[0043] FIG. 7 illustrates another Example, and is a side view of a truck 14 of a monorail
vehicle to which the traction device illustrated in FIGS. 2 to 6 is applied. FIG.
8 is a plan view of the truck 14 illustrated in FIG. 7. The same reference sign is
given to a part having a common or similar effect to a part constituting the traction
device illustrated in FIGS. 1 to 6 and a railroad vehicle including the traction device.
Only a part and a structure different from those in FIGS. 1 to 6 will be described.
[0044] A truck frame 70 of the truck 14 of a monorail vehicle includes three types of wheels,
a running wheel 35, a guiding wheel 36, and a stabilizing wheel 37. The running wheel
35 is a wheel for supporting a load of a vehicle body 13 of the monorail vehicle and
the truck 14 thereof in a vertical direction, and rolls on an upper surface of a track
beam 2 having a rectangular cross section. The guiding wheel 36 rolls at an upper
end of a side surface of the track beam 2 in a horizontal plane, and guides the monorail
vehicle in a rolling direction along the track beam 2 when the monorail vehicle travels
on a curved track. The stabilizing wheel 37 rolls at a lower end of a side surface
of the track beam 2 in a horizontal plane, and maintains a stable posture such that
the monorail vehicle does not fall down on the track beam 2.
[0045] A traction device 20 illustrated in FIGS. 7 and 8 is basically obtained by disposing
a link shaft 21 (refer to FIGS. 2 to 6) disposed so as to pass through side beams
71 on the left and the right between transverse beams 72 on upper surfaces of the
transverse beams 72.
[0046] Such a structure of Example 3 can exhibit an effect similar to Examples 1 and 2 described
with reference to FIGS. 1 to 6. As a main effect thereof, offset disposition of a
link shaft at a central portion of a truck in the longitudinal direction 100 is not
necessary with respect to the conventional virtual center plate method traction device.
A length of the truck in the longitudinal direction can be thereby reduced. Such a
reduction has been required for avoiding interference between the link shaft and a
part such as a running wheel. Therefore, a monorail truck having a short wheel base
can be formed. In addition, due to the reduction in the wheel base, it is possible
to provide a traction device capable of forming a small and light monorail truck capable
of reducing a burden load of a guiding wheel when the monorail truck passes through
a curve.
Reference Signs List
[0047]
- 1
- rail
- 2
- track beam
- 10
- vehicle
- 11, 13
- vehicle body
- 12, 14
- truck
- 20
- traction device
- 21
- link shaft
- 22, 22a, 22b
- link shaft arm
- 23, 23a, 23b
- draw shaft
- 24, 24a, 24b
- link shaft bracket
- 25, 25a, 25b
- draw shaft bracket
- 26
- yaw damper
- 27
- yaw damper bracket
- 30
- axle
- 31
- wheel
- 32
- wheel shaft
- 33
- shaft spring
- 34
- axle box
- 35
- running wheel
- 36
- guiding wheel
- 37
- stabilizing wheel
- 40
- vehicle body support device
- 46
- air spring
- 70
- truck frame
- 71
- side beam
- 72
- transverse beam
- 73
- guiding wheel support frame
- 74
- stabilizing wheel support frame
- 100
- forward and backward (longitudinal) direction
- 110
- lateral (width) direction
- 120
- vertical (height) direction