[0001]
Fig. 1 is a plan view showing a typical example of a prior art switching device for
vehicle;
Figs. 2a to 2b are cross sectional views taken along the line IIa-IIa and the line
IIb-IIb of Fig. 1, respectively;
Fig. 3 is a cross sectional view of a vehicle and track according to a conventional
vehicle guiding system;
Fig. 4 is a plan view corresponding to that of Fig. which shows a switching device
for vehicle according to an embodiment of the present invention;
Fig. 5 is a cross sectional view taken along the line V-V of Fig. 4;
Fig. 6 is a view for explaining a movable or switching rail section shown in Fig.
4;
Figs. 7a, 7b and 7c are cross sectional views taken along the lines XIIa-XIIa, XIIb-XIIb,
and XIIc-XIIc of Fig. 6, respectively;
Fig. 8 is a plan view showing the switching device vehicle according to another embodiment
of the present invention;
Fig. 9 is a plan view showing the switching device for vehicle according to still
another embodiment of the present invention; and,
Fig. 10 is a cross sectional view of track, showing the difference between the vehicle
guiding system according to the present invention and that according to the prior
art, a right side illustration thereof showing the former system while a left side
illustration thereof showing the latter system.
BACKGROUND OF THE INVENTION:
FIELD OF THE INVENTION
[0002] The present invention relates to a switching device for vehicle, applied to a vehicle
guiding system wherein a vehicle is guided by its guide wheels allowed to rotate within
a horizontal plane.
[0003] Many of those vehicles arranged to travel on an exclusive track through their rubber
made tires are guided leftwards or rightwards by means of their wheels which are provided
horizontally.
[0004] Fig. 1 shows a prior art vehicle of such type and a switching device for vehicle
involved. The vehicle A has a travel wheel 3 of rubber tire and travels on an exclusive
track 10. In other track section than that in which the switching device is installed,
the vehicle A is guided by travel of its guide wheels along their corresponding rail
and by detecting the position of the vehicle A relative to the rail, or the variation
thereof and by steering the travel wheel 3 accordingly.
[0005] The track includes a general section and a switching section when it is roughly classified.
Usually, in the general section, main rails 11L and 11R are provided on both sides
of the track and, in the switching section, an auxiliary rail 12L and movable guide
plate 13L, and an auxiliary rail 12R and movable guide plate 13R are added to the
main rails 11L and 11R, respectively, as shown in Fig. 1.
[0006] In Fig. 2, a sectional view of the vehicle A is shown. As seen, the guide wheels
which are provided horizontally include two types of guide wheels, one of which is
main wheels 1 and the other of which is switching wheels 2. In the vehicle shown in
Figs. 2a and 2b, the main wheels 1 are guided by the main rails 11L, 11R while the
switching wheels 2 are guided by the auxiliary rails 12L, 12R or guide plates 13L,
13R. Practically, it is desirable that the main wheels and main rails are located
at an upper stage or position with the switching wheels and auxiliary rails being
located at a lower stage or position. Thus, the main rail and auxiliary rail have
the different heights of guide surface and are not opposed to each other.
[0007] When the vehicle travels on the track of general section, the main wheels 1 respectively
provided on the right and left sides of the vehicle are guided by the right and left
main rails 11L, 11R, respectively. In the switching section of track, the switching
wheels of one side are guided by and along a corresponding one of the wheel ways
H respectively provided between the main rails and auxiliary rails on both sides of
the track. For selecting the course of the vehicle, in a switching section the movable
guide plates 13L and 13R are provided in such a manner as to be connected to the auxiliary
rails, respectively, and are pivotally supported by pins 13', respectively. The other
end of the movable guide plates, as in the case of a point installed on a railway,
is made rightwardly or leftwardly movable by a switching device 14 whereby the wheel
way H is selectively formed on either one side of the track 10.
[0008] The construction of such switching device for vehicle is known as dissolved in Japanese
Utility Model Laid-Open No. 126303/80, Japanese Patent Publication No. 264/81, Japanese
Utility Model Laid-Open No. 123001/80, or Japanese Patent Laid-Open No. 39807/76.
[0009] In the prior art, however, the above-mentioned two types of guide wheels, i.e., main
wheels and branching wheels are always used as the horizontal guide wheels. Further,
such arrangement of prior art intends, as understandable from Figs. 2a and 2b, that,
during the travel of the vehicle in the switching section, any of main wheel and switching
wheel is allowed to contact with the main rail or auxiliary rail only on one side
of the wheel, whereby to prevent the wheels from making their reverse rotation and
being much frictionally worn. Providing the switching wheels in the same number as
that of the main wheels, however, means that a valuable space is employed only for
the purpose of performing the switching operation which occupies a very small percentage
in the entire travelling operation of the vehicle. This is not preferable from the
viewpoint of spatial efficiency. On the other hand, while the branching wheels perform
a very important function of selecting the course of the vehicle, a failure involved
in such branching wheel will result in a great accident. For this reason, a large
amount of labour is spent for their maintenance and inspection similarly as in the
case of for maintenance and inspection of the main wheels.
[0010] In the meantime, since the guide wheel 1 and the corresponding switching wheel 2
are vertically arranged in upper and lower stages, the respective positions of the
main rails 11L and 11R become correspondingly high and the space required for installing
the rails becomes correspondingly large. Accordingly, a space for providing power
rails 15 provided on the side of the track and used to supply a power, as well as
a space for providing a current collector 4 on the side of the vehicle becomes necessarily
small.
[0011] Further, in the switching device of the above-mentioned system, the movable guide
plates are pivotally supported by the pins 13' as shown in Fig. 1, it becomes necessary
to make dimentional adjustment of the device, make replacement of the worn pins or
bushes, effect the supply of oil to the relevant parts, etc. Namely, there remains
some problem of maintenance unsettled. Further, since, in such branching device, the
movable guide plates are constructed in the form of a straight line, the device has
a problem that it fails to provide a smoothness when the vehicle passes through it.
SUMMARY OF THE INVENTION:
[0012] In view of the above, the object of the present invention is to provide a switching
device for vehicle which eliminates the above-mentioned problems inherent in the prior
art, which is simple in construction, which is easy to maintain, and which makes it
possible for the vehicle to have wider space for providing a current collector or
power rails and to make a smooth switching movement. The present invention has been
accomplished by discovering that the problems considered important in the prior art,
i.e., the above-mentioned problems that when single guide wheel is guided between
two vertical walls of a wheel way, it is brought alternatingly into contact with either
of the two vertical walls of the wheel way and is thereby caused repeatedly to make
its normal and back rotations and thus frictionally worn very much, are practically
not serious problems, that is to say, by discovering that such problems are practically
not fatal problems for the reasons that the guide wheel in the switching section is
likely to be guided in contact with only one side wall of the wheel way; that, on
the other hand, the length of the switching section is remarkably short as compared
with the entire length of the track; etc. Further, the present invention has been
materialized with conception that the auxiliary rails and movable guide plates need
not be high in stiffness since they are solely intended to guide only the guide wheels
for obtaining a steering signal unlike those intended to guide the travelling wheels
as in case of a railway.
[0013] The above object of the present invention is attained by arranging the main rails
and the corresponding auxiliary rails such that the vertical guiding surface of the
former rail and that of the latter rail are opposed to each other with the same height.
Further, the above another object of the present invention is attained by preparing
the movable rail in a manner that it is integrally and bendably connected at one end
to a auxiliary rail or main rail by reducing lateral stiffness of connecting portion
and the other free end of the movable rail is made flexible.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS:
[0014] An embodiment of the present invention will now be described with reference to the
accompanying drawings.
[0015] In Fig. 4, over the substantially entire length of a switching section S having main
rails 11L and 11R provided thereon, auxiliary rails 12L and 12R being paired with
the main rails 11L and llR, respectively, are provided inside these rails 11L and
11R, respectively. A portion of the auxiliary rail 12L adjacent to an entrance of
the switching section S forms a swingable rail 12M, thus defining a switching section
M..Assume now that a vehicle A mounted, at its right and left sides, with guide wheels
1 arranged to rotate within a horizontal plane, comes on from a direction indicated
by an arrow. Then, the vehicle, in accordance with the position of the swingable rail,
advances rightwards by having its right guide wheels guided along a right wheel road
Hr, or alternatively advances leftwards by having its left guide wheels guided along
a left wheel way H£. As seen in Fig. 5, a vertical guiding surface of the main rail
11 and a vertical guiding surface of the auxiliary rail 12L, 12R or movable rail 12M
are same in height and made to oppose each other with one guide wheel 1 interposed
or guided therebetween.
[0016] In this embodiment, the swingable rail 12M is constructed in such a manner as to
continue from the fixed or stationary auxiliary rail 12L, and a bending portion 20
is made small in the lateral stiffness and thereby made flexible or bendable. A free
end portion 12F (indicated by a-one-dot chain line in Fig. 4) of the swingable rail
12M is also made small or less in the lateral stiffness, whereby, when it is contacted
with the main rail, it flexes to form a smooth guiding surface.
[0017] In the meanwhile, the auxiliary rail 12R of the branching side is also fixedly provided
over the substantially entire switching section S. In this case, however, an end 12F'
of the auxiliary rail 12R is retreated from a point corresponding to said free end
portion F, to such an extent that, when the vehicle advances straight along the rails
11L and 12L, no hindrance arises in passing of its right-side guide wheel 1. The ends
12E', 12F' of the auxiliary rail 12R, as well as the respective ends 12E, 12F of the
auxiliary rail 12L and swingable rail 12M, should be extended up to the positions
at which the vehicle can reliably be guided by only main rail 11L and opposing main
rail 11R. Further, the swingable rail-12M may of course be provided on the auxiliary
rail 12R.
[0018] Figs. 6, 7a, 7b and 7c each show a detailed structure of an embodiment of the swingable
rail 12M shown in Figs. 4 and 5. Cross-sectional shapes of main. rail 11L and swingable
rail 12M are, however, not limited to those shown in these figures. In Fig. 7C, the
cross section of the free end portion is shown, which joins the movable rail 12M to
the corresponding main rail 11L. As seen, horizontal and vertical webs of the T-shaped
movable rail 12M have their respective parts omitted or cut away, whereby the movable
rail 12M is reduced in the lateral stiffness. Thus, the swingable rail 12M is made
flexible and thereby made capable of being pressed contact with the main rail so that
it may have a smooth guiding surface. The reduced thickness of vertical webs is helpful
for a smooth guiding..Further, the cross section (b-b) of an intermediate portion
of the swingable rain 12M indicates that no particular fabrication is required in
this intermediate portion. In the cross section (a-a) of a bending portion of the
swingable rail 12M, a horizontal web thereof has its parts omitted or cut away, whereby
reducing the lateral stiffness. Further, as shown in Fig. 6, the swingable rail 12M
may be provided with an embossed portion 21 for reliably introducing the guide wheel
1 residing on the opposite side from the swingable rail 12M into the corresponding
wheel road Hr. The necessity of the embossed portion 21 depends on the positional
relation between the bending portion 20 and the end portion 12F' of the opposing auxiliary
rail 12R, this is, the embossed portion 21 is not required in case that the end portion
12F' is located more toward the entrance of switching section than the bending portion
20, or in case that swingable rails are provided on both sides of the track as will
be mentioned later.
[0019] In Fig. 8, there is shown another embodiment of the swingable rail 12M, in which
the swingable rail is provided on each of the auxiliary rails 12L, 12R. The one-side
swingable rail 12ML is made linear correspondingly to the form of its corresponding
main rail while the other-side swingable rail 12MR is made curvilinear. This embodiment
provides a structure suitable for the passing of the vehicle through the switching
section at high speed. The swingable rails 12ML and 12MR have bending portions 20L
and 20R, respectively, and are made operable in interlocking relation with each other.
The end portions 12FL and 12FR of the swingable rails 12ML and 12MR are pointed or
made sharp, as same as in case of Fig. 6.
[0020] When the movable rail 12ML is pressed against the main rail 11L by the switch-over
force of the switching device 14, a portion of the swingable rail 12ML which resides
in the vicinity of the free end 12FL thereof is caused to flex or bend due to its
elasticity and is thereby pressed contact with the main rail 11L. Thus, a desired
smooth guiding surface is obtained. Since the swingable rail 12MR of opposite side
is made curvilinear, it is possible to cause both the swingable rails 12ML and 12MR
to suitably share a load applied from the guide wheels if, for example, stoppers 23
are located at the center side of the track. Where, on the contrary, the vehicle takes
the straight course, pressing the swingable rail 12MR against the corresponding main
rail llR by the switching device would cause the swingable rail 12MR to flex to pressed
contact with the main rail 11R. Thus, a substantially linear rail form or guiding
surface is obtained. At this time, the movable rail 12ML of opposite side is restored
to its original linear form, whereby the guide wheels are guided without hindrance.
Constructing the swingable rail 12
ML or 12M
R in a manner that it has the bendable portion 20L or 20R,.or the sharp or pointed
end portion 12FL or 12FR, is possible as is in the preceding embodiment.
[0021] Fig. 9 shows still another embodiment of the present invention. This embodiment refers
to a switching device wherein the auxiliary rails 12L and 12R are disposed outside
the main rails 11L and 11R, respectively. The interspace between each main rail and
its corresponding auxiliary rail is given as a wheel way H, and the corresponding
guide wheels pass through this wheel way H. Even in such a switching device, the above-mentioned
elasticity characteristic can be applied to the swingable rails 12ML and 12MR. In
the switching device of this embodiment, however, it is impossible to construct the
main rail on a continuous basis as in the preceding embodiments. That is, in the switching
device of this type, it becomes unavoidably necessary to provide a clearance or passage
22 for passing the swingable rails.
[0022] In any case of the foregoing descriptions, reference was made to the case where the
height of the main rails is made same as the height of the auxiliary rails. With such
construction, it is possible, as stated before, to omit the provision of the branching
wheel 2 to the vehicle, and also to make the constructing of the current collector
4 and the power rails 15 on the I track easy.
[0023] However, it is also possible to improve.the switching device already in service for
passing a vehicle equipped with the prior art guiding system in a manner simply to
make the movable rail at both ends laterally bendable, resulting in a simple machanism
of the switching section and in a smooth passing of the vehicle through the switching
section.
[0024] Fig. 10 shows the difference between the vehic guiding system according to the present
invention shown at right side and that according to the prior art shown in left side.
As seen in Fig. 10, the heightwise space necessary for the guide wheel section of
the present invention becomes smaller as compared with that of the prior art, and
the height of the main rail is reduced correspondingly to that of the guide wheels,
by amount of Ah = hl - h2. As a result, the arm of moment applied to the main rail
from the guide wheel become shorter, and the space for accommodating the power rails
15 become wider.
[0025] The present invention has the following effects.
(1) The vehicle has only main guide wheels, but no switching wheels. This makes it
possible to omit the expenditures and labour involved in the manufacture and maintenance
of such switching wheels.
(2) The heights of guide wheels as well as of main rails are reduced. As a result,
installation of the current collector 4 in the vehicle and of the power rails 15 in
the track become easier due to their wider spaces, and the support column 24 for the
main rail may be light-structured due to the reduced arm length of moment applied
thereon.
(3) Since, according to the invention, the supporting of the branching device is effected
by elastic flexure or deformation instead of by hinge joints with pins, it is possible
to eliminate the complexity in manufacture and maintenance which might be caused by
the hinge joints with pins. And,
(4) Since, according to the present invention, it is possible, by utilizing the elastic
deformation of the swingable rail itself, to provide a smooth guiding surface at the
switching portion of the track, the comfortable ride of passengers being obtained.