U.S. patent application number 16/349136 was filed with the patent office on 2019-09-05 for model car racing track.
The applicant listed for this patent is Stadlbauer Marketing + Vertrieb GmbH. Invention is credited to Christian Koker, Christian Rathge.
Application Number | 20190270025 16/349136 |
Document ID | / |
Family ID | 57583788 |
Filed Date | 2019-09-05 |
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United States Patent
Application |
20190270025 |
Kind Code |
A1 |
Koker; Christian ; et
al. |
September 5, 2019 |
MODEL CAR RACING TRACK
Abstract
A model car racetrack with at least one model car which is
guided along a lane, a roadway which defines the lane, wherein the
roadway has at least one bus bar which extends in the direction of
the lane, and a transformer arrangement comprising a primary
element and a secondary element for contact-free energy
transmission from the roadway to the model car, wherein the bus bar
is the primary element of the transformer arrangement and the model
car represents the secondary element of the transformer arrangement
for coupling in the electromagnetic field which is produced by the
primary element.
Inventors: |
Koker; Christian;
(Mahlwinkel, DE) ; Rathge; Christian; (Irxleben,
DE) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Stadlbauer Marketing + Vertrieb GmbH |
Salzburg |
|
AT |
|
|
Family ID: |
57583788 |
Appl. No.: |
16/349136 |
Filed: |
November 21, 2017 |
PCT Filed: |
November 21, 2017 |
PCT NO: |
PCT/EP2017/001362 |
371 Date: |
May 10, 2019 |
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
A63H 18/12 20130101;
A63H 30/04 20130101 |
International
Class: |
A63H 18/12 20060101
A63H018/12; A63H 30/04 20060101 A63H030/04 |
Foreign Application Data
Date |
Code |
Application Number |
Nov 22, 2016 |
DE |
20 2016 007 185.9 |
Claims
1. A model car racing track having at least one model car guided
along a lane and a track defining the lane, wherein the track has
at least one bus_bar extending in the direction of the lane,
including a transformer arrangement with a primary element and a
secondary element for contact-free and interruption-free
transmission of energy and control signals from the track to the
model car, wherein the bus_bar is arranged on a surface of the
track and is the primary element of the transformer arrangement
extending in the direction of the lane, and the model car comprises
the secondary element of the transformer arrangement for coupling
in the electromagnetic field generated by the primary element,
wherein the secondary element has a winding or a plurality of
windings, wherein the winding or plurality of windings defines a
screw vector (S) extending horizontally in a width direction Y
which extends substantially at right angles to the direction of the
lane.
2. The model car racing track of claim 1, wherein a rotation vector
(R) of the electromagnetic field generated by the primary element
points substantially in the direction of the lane.
3. The model car racing track of claim 1, wherein the secondary
element has a main direction of extension (H) which is
substantially at right angles to the direction of the lane.
4. (canceled)
5. The model car racing track of claim 1, wherein at least one
second lane with at least one second bus_bar is provided, along
which a second model car is guided along the lane, wherein an
electrical current with a first frequency is applied to the first
bus_bar and a second electrical current with a second frequency is
applied to the second bus_bar, wherein the first frequency is
different from the second frequency.
6. The model car racing track of claim 5, wherein the second
frequency is at least one and a half times the first frequency.
7. The model car racing track of claim 5, wherein the first
frequency is 400 kHz and the second frequency 600 kHz.
8. The model car racing track of claim 1, wherein the at least one
lane has two parallel bus_bars extending in the direction of the
lane.
9. The model car racing track of claim 8, wherein the two bus_bars
of a lane are wired electrically in parallel.
10. The model car racing track of claim 8, wherein the two bus_bars
of a lane are wired electrically in series.
11. The model car racing track of claim 7, wherein the at least one
lane has two parallel bus bars extending in the direction of the
lane.
12. The model car racing track of claim 11, wherein the two bus
bars of a lane are wired electrically in parallel.
13. The model car racing track of claim 11, wherein the two bus
bars of a lane are wired electrically in series.
Description
BACKGROUND OF THE INVENTION
1. Field of the Invention
[0001] The invention relates to a model car racing track. More
specifically, the invention relates to a model car racing track
having a transformer arrangement for contact-free energy
transmission from the track to a model car, where the track bus bar
represents the primary element of the transformer arrangement, and
the model car represents the secondary element for coupling in the
electromagnet field generated by the primary element.
2. Description of Related Art
[0002] A model car racing track, also known as a slot-car track or
slot track, is a technical apparatus with which electrically-driven
model cars can be driven in a guided manner along lanes, wherein a
guide keel on the model car engages in a slot on the track.
[0003] The model car racing track comprises a track which can for
example be assembled from a plurality of track sections which can
be plugged together. The track can have two lanes which in each
case possess a slot for guiding a model car and two bus bars for
the current supply of the electrical drive of the model vehicles
which can be moved along the respective lane. Current collectors on
the respective model cars are thereby in contact with the
respective bus bar in order to guarantee a transmission of
electrical energy. The speed and braking behavior of the respective
model car can in each case be controlled using a hand-held
controller. However, when driving round a curve for example, due to
centrifugal forces acting on the model cars it can happen that the
contact between the bus bar and the current collector of the model
car is interrupted, with the consequence that the energy supply to
the electrical drive of the model car is interrupted and the model
car loses speed.
SUMMARY OF THE INVENTION
[0004] The invention is based on the object of showing a way how an
interruption-free supply with electrical energy of model cars of
such a model car racing track can be guaranteed.
[0005] According to the invention, this object is achieved through
a model car racing track of the aforementioned type with the
characterizing features of the independent claims. Advantageous
embodiments of the invention are described in the further dependent
claims.
[0006] The above and other objects, which will be apparent to those
skilled in the art, are achieved in the present invention which is
directed to a model car racing track having at least one model car
guided along a lane and a track defining the lane, wherein the
track has at least one bus bar extending in the direction of the
lane, including a transformer arrangement with a primary element
and a secondary element for contact-free and interruption-free
transmission of energy and control signals from the track to the
model car, wherein the bus bar is arranged on a surface of the
track and is the primary element of the transformer arrangement
extending in the direction of the lane, and the model car comprises
the secondary element of the transformer arrangement for coupling
in the electromagnetic field generated by the primary element,
wherein the secondary element has a winding or a plurality of
windings, wherein the winding or plurality of windings defines a
screw vector (S) extending horizontally in a width direction Y
which extends substantially at right angles to the direction of the
lane.
[0007] A rotation vector (R) of the electromagnetic field generated
by the primary element points substantially in the direction of the
lane. The secondary element has a main direction of extension (H)
which is substantially at right angles to the direction of the
lane.
[0008] At least one second lane with at least one second bus bar is
provided, along which a second model car is guided along the lane,
wherein an electrical current with a first frequency is applied to
the first bus bar and a second electrical current with a second
frequency is applied to the second bus bar, wherein the first
frequency is different from the second frequency.
[0009] The second frequency is preferably at least one and a half
times the first frequency, for example, the first frequency may be
400 kHz and the second frequency may be 600 kHz.
[0010] The at least one lane may have two parallel bus bars
extending in the direction of the lane, where the two bus bars of a
lane are wired electrically in parallel or wired electrically in
series.
BRIEF DESCRIPTION OF THE DRAWINGS
[0011] The features of the invention believed to be novel and the
elements characteristic of the invention are set forth with
particularity in the appended claims. The figures are for
illustration purposes only and are not drawn to scale. The
invention itself, however, both as to organization and method of
operation, may best be understood by reference to the detailed
description which follows taken in conjunction with the
accompanying drawings in which:
[0012] FIG. 1 shows a schematic sectional representation of a
preferred embodiment of a model car racing track according to the
invention;
[0013] FIG. 2 shows a schematic representation of a transformer
arrangement which is used in the model car racing track shown in
FIG. 1;
[0014] FIG. 3 shows a view from above of the first substrate
element shown in FIG. 2;
[0015] FIG. 4 shows a view from below of the second substrate
element shown in FIG. 2;
[0016] FIG. 5 shows an operating scenario of the model car racing
track shown in FIG. 1;
[0017] FIG. 6 shows a first wiring variant of bus bars of a track
with two lanes;
[0018] FIG. 7 shows a second wiring variant of bus bars of a track
with two lanes; and
[0019] FIG. 8 shows a further exemplary embodiment of a model car
racing track according to the invention, with a track provided with
a bus bar for each lane of the track, which has several lanes.
DESCRIPTION OF THE PREFERRED EMBODIMENT(S)
[0020] In describing the preferred embodiment of the present
invention, reference will be made herein to FIGS. 1-8 of the
drawings in which like numerals refer to like features of the
invention.
[0021] For this purpose, in a model car racing track of the
aforementioned type, according to the invention a transformer
arrangement comprising a primary element and a secondary element
for contact-free energy transmission from the track to the model
car is provided, wherein the bus bar is the primary element of the
transformer arrangement and the model car comprises the secondary
element of the transformer arrangement for coupling in the
electromagnetic field generated by the primary element. In other
words, the model car racing track has an air-core transformer for
contact-free energy transmission, wherein the primary element
performs the function of a primary coil or winding and the
secondary element performs the function of a secondary coil or
winding.
[0022] This has the advantage that no temporary interruption of an
electrical contact between a bus bar and a current collector, and
thus no interruption of the supply with electrical energy, can
occur. Furthermore, an unmodified track with a particularly simple
structure can be used in which the bus bars are configured as
conductors extending in the direction of travel or lane direction.
In addition to the transmission of operating energy, control
signals can also be transmitted with the transformer arrangement,
for example in order to accelerate or brake the model car, for
example in that these control signals are modulated with a higher
frequency and filtered out again on the model car side.
[0023] According to a preferred embodiment, a rotation vector of
the electromagnetic field generated by the primary element points
substantially in the direction of the lane. The bus bar, configured
as a conductor extended in the direction of the lane, forms a
magnetic field, the field lines of which have the form of closed,
concentric circles or ellipses around the bus bar. In this case a
rotation vector of the magnetic field, which stands perpendicular
to the concentric circles, points in the direction of the lane.
"Substantially" is thereby understood to mean within usual
manufacturing tolerances. Thus, an unmodified track with a
particularly simple structure can be used in which the bus bars are
configured as conductors extending in the direction of travel or
lane direction. Tracks with integrated coil elements, which are
complex to manufacture, are not necessary.
[0024] According to a further preferred embodiment, the secondary
element has a main direction of extension which is substantially at
right angles to the direction of the lane.
[0025] According to a further preferred embodiment, the secondary
element has a winding or a plurality of windings, wherein the
winding or plurality of windings defines a screw vector which
extends substantially at right angles to the direction of the lane.
The plurality of windings defines a main direction of extension of
the secondary element in the helical direction of the secondary
element. Thus, the secondary element can have a different
orientation than the primary element, which makes possible a
construction-space-saving arrangement within the model car.
[0026] According to a further preferred embodiment, at least one
second lane with at least one second bus bar is provided, along
which a second model car is guided along the lane, wherein an
electrical current with a first frequency is applied to the first
bus bar and a second electrical current with a second frequency is
applied to the second bus bar, wherein the first frequency is
different from the second frequency. In this way, mutual influences
through the inductive coupling-in of electrical energy are avoided
or at least reduced.
[0027] According to a further preferred embodiment, the second
frequency is at least one and a half times the first frequency. In
this way, a mutual influence through the inductive coupling-in of
electrical energy can be reduced particularly effectively.
[0028] According to a further preferred embodiment, the first
frequency is 400 kHz and the second frequency 600 kHz. Through the
selection of these frequencies, a particularly effective energy
transmission can be achieved on the one hand, and on the other hand
minimal interference with other electro-technical or electronic
devices in the vicinity of the model car racing track can be
achieved.
[0029] According to a further preferred embodiment, the at least
one track has two parallel bus bars extending in the direction of
the lane. Here too, an unmodified track with a particularly simple
structure can be used in which the bus bars are configured as
conductors extending in the direction of travel or lane
direction.
[0030] According to a further preferred embodiment, the two bus
bars are wired electrically in parallel. In this way, a doubled
conductor cross section is made available, so that a doubled
current strength can be applied to the bus bar elements.
Furthermore, this means that, in the event of an interruption of
one of the two bus bar elements, electrical current still flows
through the other bus bar element. This increases the reliability
of the supply of a model car with electrical energy.
[0031] According to a further preferred embodiment, the two bus bar
elements are wired electrically in series. Thus, the two bus bar
elements form a double loop, which further improves the efficiency
of the energy transmission.
[0032] The invention is described in more detail in the following
with reference to the drawings.
[0033] A model car racing track 2, also known as a slot-car track
or slot track, is represented in FIG. 1.
[0034] The model car racing track 2 has a track 4 made up of a
plurality of track sections which can be plugged together with, in
the present exemplary embodiment, two lanes 6a, 6b, each for a
model car 10. Only one model car 10 is illustrated in FIG. 1.
[0035] In the present exemplary embodiment, the track 4 has a
recess 8a, 8b assigned to each lane 6a, 6b which is arranged
centrally relative to the lane and in which a guide element 30, for
example a guide pin or guide keel of the model car 10, engages and
so effects a guidance of the model car 10 along the respective
lane, in this case the lane 6a.
[0036] Furthermore, in the present exemplary embodiment the track 4
has in each case two bus bars 14a, 14b, 14c, 14d arranged on each
side of the respective recess 8a, 8b which are assigned to the
first lane 6a or the second lane 6b. In the present exemplary
embodiment, the first and second bus bars 14a, 14b, 14c, 14d have a
u-formed profile in cross section and are pressed into further
recesses in the track 4. In departure from the present exemplary
embodiment, the first and second bus bars 14a, 14b, 14c, 14d can
also have a different profile in cross section.
[0037] The bus bars 14a, 14b, 14c, 14d are in each case formed in a
single piece and of the same material. Furthermore, the bus bars
14a, 14b, 14c, 14d are manufactured of a magnetic material. In this
way, the model car 10 can be held in the lane 6a through magnetic
force by means of a permanent magnet (not shown) which interacts
with the bus bars 14a, 14b.
[0038] As will be explained later, the two bus bar pairs 14a, 14b
or 14c, 14d form a primary element 18 of a transformer arrangement
16 for contact-free energy transmission to the model car 10.
[0039] The transformer arrangement 16 for contact-free energy
transmission to the model car 10 also includes a secondary element
20 assigned to the model car 10 for coupling in the electromagnetic
field generated by the primary element 18.
[0040] In the present exemplary embodiment, the secondary element
20 is a coil arrangement 22.
[0041] In addition to the transmission of operating energy, control
signals can also be transmitted with the transformer arrangement
16, for example in order to accelerate or brake the model car 10,
for example in that these control signals are modulated with a
higher frequency and filtered out again on the model car side.
[0042] Reference is now made, in addition, to FIG. 2, which for
reasons of simplicity only shows the first lane 6a of the two lanes
6a, 6b. However, the following explanations also apply analogously
to the second lane 6b with the recess 8b and the bus bars 14c and
14d.
[0043] FIG. 2 shows that both the recess 8a and also the two bus
bars 14a, 14b each have a main direction of extension H pointing
along the lane 6a in the direction of travel, in which direction
its dimensions are significantly greater than in the direction of
the other directions of extension.
[0044] Furthermore, FIG. 2 shows that the coil arrangement 22 has a
substrate 12. In the present exemplary embodiment, the substrate 12
has a first substrate element 24a and a second substrate element
24b as well as a ferrite core 26 arranged between the first
substrate element 24a and the second substrate element 24b.
[0045] In the present exemplary embodiment, the first substrate
element 24a and the second substrate element 24b are in each case a
circuit board. The circuit boards have a basic shape extending in a
planar manner, in the present exemplary embodiment a rectangular
basic shape, with in each case an upper side and an underside
opposite the upper side. They consist in each case of an
electrically insulating material and conductor paths arranged
thereon. Fiber-reinforced plastic is for example commonly used as
insulating material. The conductor paths are for example etched
from a thin coating of copper applied previously to the insulating
material.
[0046] In the present exemplary embodiment, conductor paths on the
upper side of the first substrate element 24a form a plurality of
first coil portions 28a, while in the present exemplary embodiment
further conductor paths on the underside of the second substrate
element 24b form a plurality of second coil portions 28b. In each
case one of the first coil portions 28a and one of the second coil
portions 28b together form a coil winding of the coil arrangement
20.
[0047] For this purpose, connecting lines (not shown) are provided
which extend through the first substrate element 24a and the second
substrate element 24b and connect the respective first coil
portions 28a with the respective second coil portion 28b in an
electrically conductive manner. Thus, in the present exemplary
embodiment the coil portions 28a, 28b form three coil windings.
However, five to eight coil windings could also be provided.
[0048] Furthermore, FIG. 2 shows that the ferrite core 26 is
arranged with its upper side on an underside of the first substrate
element 24a and the underside of the ferrite core 26 is arranged on
an upper side of the second substrate element 24b.
[0049] The ferrite core 26 is a component made of ferrite which, as
core of the coil arrangement 22, increases its inductance or guides
the magnetic field. Ferrites are understood to be materials
comprising poorly electrically conductive or non-conductive
ferrimagnetic ceramic materials made from the iron oxide haematite
(Fe.sub.2O.sub.3), magnetite (Fe.sub.3O.sub.4) and/or from further
metal oxides. Depending on the composition, ferrites are hard
magnetic or soft magnetic.
[0050] The coil windings formed by the respective first coil
portions 28a and second coil portions 28b have a screw vector S
which, as illustrated in FIG. 2, lies substantially within the
plane of the substrate 12 and describes the helical configuration
of the coil windings of the coil arrangement 22.
[0051] It can also be seen that the screw vector S is arranged
substantially at right angles to the main direction of extension H
of the bus bars 14a, 14b.
[0052] Furthermore, FIG. 2 shows that the substrate 12 has a first
direction of extension I, a second direction of extension II and a
third direction of extension III.
[0053] In the present exemplary embodiment, the first direction of
extension I extends in a height direction Z between the first
substrate element 24a and the second substrate element 24b. The
second direction of extension II extends at right angles to the
first direction of extension I in the direction of the screw vector
S or in a width direction Y. Furthermore, the third direction of
extension III extends at right angles to the first direction of
extension I and to the second direction of extension II in the
direction of the main direction of extension H or in a depth
direction X.
[0054] In the present exemplary embodiment, the substrate 12, the
first substrate element 24a, the second substrate element 24b and
the ferrite core 26 in each case have significantly greater
dimensions in the direction of the second direction of extension II
and the third direction of extension III than in the direction of
the first direction of extension I. In other words, they in each
case have a rectangular, in particular plate-formed basic
shape.
[0055] Reference is now made, in addition, to FIGS. 3 and 4.
[0056] FIGS. 3 and 4 show that the first coil portions 28a and the
second coil portions 28b have an elongated form, i.e., their
respective dimensions in the direction of the third direction of
extension III are greater than in the direction of the second
direction of extension II. Furthermore, the first coil portions 28a
and the second coil portions 28b extend at an angle to the second
direction of extension II which is unequal to a right angle. In the
present exemplary embodiment, the first coil portions 28a and the
second coil portions 28b extend at an angle of 75.degree. to
85.degree. or 95.degree. to 110.degree. to the second direction of
extension II.
[0057] In this way, a coil arrangement 22 is provided which is
particularly compact and takes up little construction space.
Furthermore, the manufacture of the coil arrangement 22 is
simplified in each case through the planar formation of the first
coil portions 28a and second coil portion 28b on the upper or
underside of the substrate 12, since planar or thick film
technology can be used for this purpose.
[0058] The operation of the model car racing track 2 will be
explained with additional reference to FIG. 5, wherein, for reasons
of simplicity, of the primary element 18, only the first bus bar
14a of the two bus bars 14a, 14b of the first lane 6a is
illustrated.
[0059] In operation, an alternating current with a frequency of 400
kHz flows through the bus bar 14a. A magnetic field M is formed
around the bus bars 14a with concentric field lines extending
around the bus bar 14a. The course of the field lines can be
described by a rotation vector R standing perpendicular to the
plane which is described by the field lines.
[0060] The field lines pass through the secondary element 20 or the
coil arrangement 22 and generate, through induction, an electrical
voltage in the secondary element 20. The electrical voltage induced
in the secondary element 20 can then be used to supply an
electrical drive of the model car 10, so that the model car 10 can
move in the direction of travel F predetermined by the main
direction of extension H of the recess 8a or the bus bar 14a. Thus,
the direction of travel F and the rotation vector R are oriented
substantially at right angles to one another. "Substantially" is
thereby understood to mean within usual manufacturing
tolerances.
[0061] A regulation of the speed of the model car 10 can thereby be
achieved through a change in the current strength of the electrical
current which flows through the bus bars 14a, 14b.
[0062] Due to the contact-free transmission of electrical energy,
contact interruptions, such as occur in the prior art, can be
avoided and interruption of the supply with electrical energy no
longer occurs.
[0063] In addition to the first lane 6a shown in FIG. 1, in the
present exemplary embodiment the second lane 6b for a second model
car (not shown) is provided which has the same structure as the
first lane 6a. However, in order to avoid, as far as possible,
interferences between two model cars 10 and thus disturbances in
the energy transmission, the bus bars 14c, 14d of the second lane
6b are flowed through by an electrical current with a frequency
which is at least one and a half times as high as the first
frequency. In the present exemplary embodiment, the second
frequency is 600 kHz.
[0064] Reference is now made, in addition, to FIGS. 6 and 7, which
show by way of example wiring variants of the two bus bar pairs
14a, 14b or 14c, 14d with reference to the first lane 6a of the two
lanes 6a, 6b of the track 4.
[0065] FIG. 6 shows a first wiring variant in which the two bus
bars 14a, 14b of the first lane 6a are wired electrically in
parallel. This allows use to be made of the doubled conductor cross
section of the two bus bars 14a, 14b, so that a doubling of the
current strength applied to the bus bars 14a, 14b becomes
possible.
[0066] FIG. 7 shows a second wiring variant in which the two bus
bars 14a, 14b of the first lane 6a are wired electrically in
series. Thus, the two bus bars 14a, 14b form a double conductor
loop, so that the efficiency of the energy transmission is
improved.
[0067] Reference is now made to FIG. 8.
[0068] This shows a second exemplary embodiment of a track 4'
which, in contrast to the track 4 illustrated in FIG. 1, only has
two recesses 8a, 8b, in each of which a further exemplary
embodiment of a bus bar 14a', 14b' is fitted.
[0069] The structure of the bus bars 14a', 14b' according to this
exemplary embodiment will be explained with reference to the bus
bar 14b' assigned to the second lane 6b.
[0070] The bus bar 14b' has a u-formed profile with a groove base
32 and two flanges 34 extending from the groove base 32 which in
the present exemplary embodiment extend parallel. Extending from
each of the flanges 34 is a tongue 36 which extends within the
plane of the surface of the track 4'.
[0071] The bus bars 14a', 14b' according to this exemplary
embodiment are in each case formed in a single piece and of the
same material. Furthermore, according to this exemplary embodiment
the bus bars 14a', 14b' are manufactured of a magnetic material. In
this way, here too the model car 10 can be held in the lane 6a
through magnetic force by means of a permanent magnet (not shown)
which interacts with the bus bar 14a'. In particular, the two
tongues 36 provide an enlarged surface on which the magnetic force
can act, so that a magnet of reduced size can be used in the model
car 10 which takes up less construction space.
[0072] Furthermore, the two bus bars 14a' 14b' are fitted into the
respective recesses 8a, 8b such that the u-formed bus bars 14a',
14b' are open in an upwards direction, so that the guide element
30, for example a pin of the model car 10, can engage in the
u-formed bus bar 14a' in order in this way to guide the model car
10 along the lane 6a defined by the recess 8a. Thus, this track 4'
has a particularly simple structure with only one bus bar 14a',
14b', in the present exemplary embodiment arranged centrally, for
each of the lanes 6a, 6b, wherein the bus bars 14a', 14b' in each
case have a double function, namely as bus bar and as guide groove
for the model car.
[0073] While the present invention has been particularly described,
in conjunction with a specific preferred embodiment, it is evident
that many alternatives, modifications and variations will be
apparent to those skilled in the art in light of the foregoing
description. It is therefore contemplated that the appended claims
will embrace any such alternatives, modifications and variations as
falling within the true scope and spirit of the present
invention.
* * * * *