U.S. patent application number 12/438862 was filed with the patent office on 2010-01-28 for device having a surface displaceable in two spatial directions.
Invention is credited to Martin Schwaiger, Thomas Thummel, Heinz Ulbrich.
Application Number | 20100022358 12/438862 |
Document ID | / |
Family ID | 38776260 |
Filed Date | 2010-01-28 |
United States Patent
Application |
20100022358 |
Kind Code |
A1 |
Schwaiger; Martin ; et
al. |
January 28, 2010 |
DEVICE HAVING A SURFACE DISPLACEABLE IN TWO SPATIAL DIRECTIONS
Abstract
A device having a surface displaceable in two spatial
directions, including a carrier frame; a conveyor means disposed
such that it circulates on the carrier frame in a first direction;
a plurality of belt units, each belt unit being fastenable to the
conveyor means in such a way that it is displaceable in the first
direction, and each belt unit including: a first continuous belt
that is disposed such that it circulates on the belt unit in a
second direction; and a first driving roller for driving the first
continuous belt in the second direction; each first driving roller
being actuated by a dedicated drive; and each belt unit
additionally has a second continuous belt that is situated on the
belt unit parallel to the first continuous belt.
Inventors: |
Schwaiger; Martin;
(Moosburg, DE) ; Thummel; Thomas; (Attenkirchen,
DE) ; Ulbrich; Heinz; (Munchen, DE) |
Correspondence
Address: |
GREER, BURNS & CRAIN
300 S WACKER DR, 25TH FLOOR
CHICAGO
IL
60606
US
|
Family ID: |
38776260 |
Appl. No.: |
12/438862 |
Filed: |
August 30, 2007 |
PCT Filed: |
August 30, 2007 |
PCT NO: |
PCT/EP07/07591 |
371 Date: |
October 12, 2009 |
Current U.S.
Class: |
482/54 |
Current CPC
Class: |
A63B 22/0285 20130101;
A63B 22/0242 20130101; B65G 17/345 20130101; A63B 2022/0271
20130101 |
Class at
Publication: |
482/54 |
International
Class: |
A63B 22/02 20060101
A63B022/02 |
Foreign Application Data
Date |
Code |
Application Number |
Aug 30, 2006 |
DE |
10 2006 040 485.8 |
Claims
1. A device having a surface displaceable in two spatial
directions, comprising: a carrier frame; a conveyor means disposed
such that it circulates on the carrier frame in a first direction;
a plurality of belt units, each belt unit being fastenable to the
conveyor means in such a way that it is displaceable in the first
direction, and each belt unit comprising: a first continuous belt
that is disposed such that it circulates on the belt unit in a
second direction; and a first driving roller for driving the first
continuous belt in the second direction; each first driving roller
being actuated by a dedicated drive; and each belt unit
additionally has a second continuous belt that is situated on the
belt unit parallel to the first continuous belt.
2. The device as recited in claim 1, characterized in that the
second continuous belt is flatter and/or shorter than the first
continuous belt.
3. The device as recited in claim 1, characterized in that each
belt unit additionally has a second driving roller for driving the
second continuous belt in the second direction.
4. The device as recited in claim 1, characterized in that the
first and second continuous belt are drivable by the same driving
roller.
5. The device as recited in claim 1, characterized in that the
drives of the first driving rollers are connected in series.
6. The device as recited in claim 1, characterized in that the
drives of the driving rollers comprise hydraulic motors and/or
electric motors.
7. The device as recited in claim 1, characterized in that the
carrier structure comprises a linear guide that is displaceable in
the first direction and on which there is situated an endless
rotating feedthrough for supplying energy to a drive, connected
thereto, of a driving roller.
8. The device as recited in claim 7, characterized in that the
carrier structure comprises a support structure for supporting the
continuous belts of the belt units, such that a connection between
the endless rotating feedthrough and the drive connected thereto in
the second direction, approximately in the center of the
appertaining belt unit, can circulate together with this belt unit
in the first direction.
9. The device as recited in claim 1, characterized in that the
conveyor means comprises two traveling chains that travel in the
first direction, driven by at least one drive wheel per chain.
10. The device as recited in claim 9, characterized in that the
run-in of each chain to the associated drive wheel has a guide
surface for guiding the chain, comprising essentially two linear
segments that are essentially parallel, two clothoidal segments,
and a circular segment, in such a way that the chain goes from a
first linear segment, in which it runs essentially in the first
direction, with constant curvature into a first clothoidal segment,
and from here goes with constant curvature into the circular
segment, and then goes from here with constant curvature into the
second clothoidal segment, and from this segment goes with constant
curvature into the second linear segment.
11. The device as recited in claim 9, characterized in that each
chain can be actuated by a first and second drive wheel, the first
and/or second drive wheels of both chains each being controlled
with angular synchronism.
12. The device as recited in claim 1, characterized in that at
least one drive wheel is a polygonal wheel that can enter into
positive engagement with bolts of the respective chain.
13. The device as recited in claim 1, characterized in that the
second driving roller, together with the first driving roller, is
made to travel by the drive of the belt unit in such a way that the
first and second continuous belt have the same travel speed.
14. The device as recited in claim 1, characterized in that each
belt unit has a traction means that pulls the continuous belt to a
carrier structure of the belt unit.
15. The device as recited in claim 12, characterized in that the
traction means comprises a magnet, in particular an electromagnet,
and/or a vacuum device.
Description
[0001] The present invention relates to a device having a surface
that is capable of being displaced in two spatial directions.
[0002] Conventional treadmills have a surface that is displaceable
in one spatial direction, usually parallel to the ground or
slightly inclined relative thereto, so that a jogger can move
forward relative to this surface while remaining essentially at
rest inertially. This makes it possible to travel, as it were,
arbitrarily long distances forward or backward while staying in the
same place. Vertical treadmills, sometimes provided with artificial
grips, analogously enable an upward climbing movement. In both
cases, a continuous belt circulates in one spatial direction, so
that the upper side of the upper run (as a rule the load run) forms
the desired surface displaceable in this spatial direction.
However, disadvantageously, here it is possible to realize only a
relative movement having one degree of freedom; i.e., the user can
move forward or backward only in this spatial direction relative to
the surface.
[0003] Therefore, EP 0 948 377 B1 proposes an omnidirectional
treadmill whose surface can be displaced in two independent spatial
directions. With such a treadmill it is possible, as this document
proposes as a preferred application, to realize in particular an
artificial environment ("virtual reality," or VR). In this context,
the user can move in the two spatial directions as desired relative
to the surface without essentially changing his inertial position
relative to the surrounding room. If a visual system, such as VR
goggles or surrounding VR monitors, are connected to the system in
such a way that the environment displayed thereon changes in a
manner corresponding to the displacement of the treadmill, this can
convey to the user the subjective feeling of moving in this
environment.
[0004] In this connection, it is to be noted explicitly that, in
contrast to EP 0 948 377 B1, the present invention is not limited
to spatial directions that are essentially perpendicular to the
direction of gravity, i.e. essentially parallel to the ground. The
present invention equally comprises for example an essentially
vertical surface that is displaceable both vertically and
horizontally, and that can thus simulate for example climbing
upward and laterally.
[0005] In a first variant, EP 0 948 377 B1 realizes the
displacement in the two spatial directions in that a continuous
belt circulates in a first spatial direction. The continuous belt
has individual bodies, in particular cylinders or balls, that are
capable of rotation about an axis parallel to the first spatial
direction, so that at its uppermost circumferential point there
results a relative speed in a second spatial direction
perpendicular to the first spatial direction. The rotation of the
individual bodies is imparted via frictional contact with a second
continuous belt that circulates under the first continuous belt,
perpendicular to the direction of circulation thereof, on which
second belt the individual bodies roll under friction.
Disadvantageously, what is known as pivoting friction is present at
the point of contact between individual bodies and the second
continuous belt, because the individual body is drawn in the first
spatial direction over the second continuous belt, which is moving
rapidly in the second spatial direction, so that the body has
relative speed in the first and second spatial direction at the
same time.
[0006] In a second variant, EP 0 948 377 B1 proposes that the
individual bodies be replaced by belt units in the form of
individual continuous belts situated next to one another, each
circulating in the second spatial direction. The displacement in
the second spatial direction is imparted to the individual belt
units by rollers whose axis of rotation is oriented parallel to the
first direction of displacement and via which the individual
continuous belts are drawn along by frictional contact. Here as
well, pivoting friction disadvantageously occurs between the outer
side of the lower run of an individual continuous belt and the
rollers, because the bell units are displaced both in the first and
in the second spatial direction relative to the rollers.
[0007] This pivoting friction increases wear and limits the drive
forces that can be transmitted. It thus disadvantageously limits
the achievable displacement speeds, reaction times, and load
capacities.
[0008] Therefore, from U.S. Pat. No. 6,669,012 B1 a device is known
having a plurality of belt units that are displaced in a first
spatial direction by two conveyor chains. Each belt unit comprises
a first continuous belt that is situated on the belt unit so as to
circulate in a second spatial direction and is actuated by a
servomotor. The accommodation of the servomotor and of the control
and transmission devices connected thereto requires significant
constructive depth of the individual belt units in the spatial
direction perpendicular to the first and second directions. During
circulation of the deflecting rollers of the conveyor chains, the
individual belt units tilt about an axis parallel to the second
spatial direction. For this purpose, due to the mentioned
constructive height of the individual belt units significant gaps
must be present between two adjacent belt units.
[0009] Therefore, U.S. Pat. No. 6,123,647 proposes as an
alternative that one or both of the rollers over which the
continuous belts of the individual belt units circulate (i.e.,
rollers whose axis of rotation during the upper and lower run phase
is parallel to the first direction of displacement) be driven by a
pinion that engages in a respective toothed rack when the
individual belt unit is in the upper run phase. The axes of
rotation of the pinion and toothed racks are oriented parallel to
the first direction of displacement, and their circumferential
toothings lie in the plane of the second direction of displacement.
Because here the rotational movement of the individual continuous
belts in the second direction of displacement is now imparted not
by friction but by a positive-fit connection via pinion and toothed
rack, the above-mentioned pivoting friction can be reduced.
[0010] The two rollers over which the continuous belts of the
individual belt units travels are each connected to a conveyor belt
that circulates between each two pulleys in the first direction of
displacement. During rotation of the drive disks, the pinions tilt
about an axis of rotation that is parallel to the second direction
of displacement. Therefore, disadvantageously, here as well
intermediate spaces must be provided between the individual belt
units, the size of the spaces being on the order of magnitude of
twice the width of the pinion. If it is desired to advantageously
realize a closed surface, U.S. Pat. No. 6,123,647 proposes that the
pinions of adjacent belt units be offset relative to one another in
the third spatial direction, perpendicular to the first and second
spatial direction. In this way, the individual pinions can tilt
without interference when running in and out of the drive disk.
However, on the other hand this disadvantageously requires a second
toothed rack, so that the pinions of adjacent belt units engage in
the first or second toothed rack in alternating fashion.
[0011] The device known from U.S. Pat. No. 6,123,647 has some
disadvantages. For example, at the beginning of the upper run
phase, i.e. when a belt unit runs away from the deflection of a
drive pulley and the upper side of its continuous belt becomes part
of the usable surface, the pinions must be brought into engagement
with the toothed racks. This requires an expensive synchronization
of the pinion rotational speed to the rotational speed of the
toothed racks. Conversely, before running into the other drive
pulley and being changed over thereby to the lower run phase, the
pinions must first be taken out of engagement with the toothed
racks. Both when the pinions move into or out of engagement with
the toothed rack and during the running of the pinion into or out
of the drive pulley, shocks occur that disturb the uniform
displacement of the surface, and that also place considerable
stress on the components, in particular the drive train.
[0012] Based on the above considerations, the object of the present
invention is to make available a device having a surface that is
displaceable in two spatial directions that avoids the above-named
disadvantages of the prior art.
[0013] For this purpose, according to the present invention a
device as recited in the preamble of claim 1 is developed by the
characterizing features thereof.
[0014] A generic device having a surface displaceable in two
spatial directions comprises a carrier frame, a conveyor means that
is situated on the carrier frame circulating on the frame it in a
first direction and a plurality of belt units, each belt unit being
fastenable on the conveyor means in such a way that it is
displaceable as a whole in the first direction. Each belt unit
comprises a first continuous belt that is situated on the belt unit
and circulating on the unit in a second direction and a first
driving roller for driving the first continuous belt in the second
direction. Preferably, the first and second directions are
essentially perpendicular to one another.
[0015] Each first driving roller is actuated by a dedicated drive.
In order to keep the gaps between the successive individual belt
units as small as possible, and simultaneously to enable a tilting
of the belt units during deflection, according to the present
invention each belt unit also has at least one second continuous
belt that is situated on the belt unit parallel to the first
continuous belt. The second continuous belt can be fashioned
flatter than the first continuous belt in a direction perpendicular
to the direction of conveyance of the conveyor means and
perpendicular to the direction of circulation of the first or
second continuous belt, so that the gap between successive belt
units, necessary in order to enable the lower edges of the belt
units to pivot past one another, can be reduced. In each belt unit,
a second continuous belt can be situated at one side of the first
continuous belt of the belt unit. It is equally possible to provide
one or more second continuous belts at each side of the first
continuous belt.
[0016] The second continuous belt can be driven by a second driving
roller or by the first driving roller in order to drive the first
continuous belt in the second direction.
[0017] As is known from U.S. Pat. No. 6,123,647, a certain minimum
distance must be maintained between belt units that circulate or
travel in the first direction and that have a finite expansion in
this direction, said distance permitting a tilting of the belt
units during the deflection at the drive wheels. According to the
present invention, for this purpose in a device according to the
present invention each belt unit comprises the second continuous
belt that is situated on the belt unit parallel to the first
continuous belt, the first and second continuous belt having the
same speed of circulation.
[0018] Thus, in contrast to U.S. Pat. No. 6,123,647, here it is not
necessary to provide a second toothed rack. The actuation of both
driving rollers via the same drive ensures that both continuous
belts have the same circulation speed, so that the surface is given
a homogenous speed field.
[0019] The first and/or second driving rollers may preferably be
cylindrical, but may for example equally have a polygonal
cross-section.
[0020] Preferably, the first and second continuous belts are
fashioned such that belt units situated next to one another form an
essentially closed surface. Advantageously, here the second
continuous belt can be somewhat shorter and/or flatter. so that
space remains for a corresponding gear mechanism, for example in
the form of chains, toothed wheels, or toothed belts, between the
drive and the driving rollers. In particular, the second driving
roller can have a smaller diameter than the first driving roller,
so that an open space is formed under the second continuous belt,
in which supports, conduits, mechanisms, sensors, or the like may
be situated without having to change the gap width between two belt
units.
[0021] A device according to the present invention also does away
with the other disadvantages explained above. Because the
continuous belts are not actuated via frictional contact as in EP 0
948 377 B1, the pivoting friction that occurs there does not occur
in the present invention, reducing the associated wear and also the
transmission of large drive loads. Correspondingly, it is also
possible to realize large surfaces displaceable in two spatial
directions, providing a person situated thereon with a large radius
of action, in particular extended stride lengths or the like.
[0022] In comparison with U.S. Pat. No. 6,123,647, here no
toothings engage or disengage with one another, so that the
associated run-in and run-out shocks are avoided and the
displacement of the surface is more uniform. In addition, the
problems connected with toothings are avoided, such as changing
rigidities due to the different number of teeth that are engaged,
as well as a longitudinal torsion of the toothed racks, which makes
precise controlling of the rotational movement of the continuous
belts more difficult.
[0023] Advantageously, the separate drives are connected in series,
making it possible to supply the required energy from an inertially
stationary source to one of the drives, from which it is
transmitted to the other drives in succession. At the same time,
this also enables a homogenous controlling of all the drives, so
that all the continuous belts circulate in the second direction
with the same speed. This makes it possible to displace the overall
surface formed from the individual continuous belts homogenously in
the second direction.
[0024] In an alternative embodiment, the individual drives can also
be controlled individually, so that surface areas having different
speeds can also be realized in the second direction. For this
purpose, the individual drives can be remotely controlled, for
example via radio or infrared signals.
[0025] It is equally possible for the drives to be controlled by a
data bus, which can preferably be situated parallel to the energy
supply, or by sensors, for example roll levers or reed contacts, in
such a way as to be deactivated after the run-in to the deflection
from the load run phase and to be reactivated upon runout from the
deflection into the load run phase, in order to save energy and to
avoid unnecessary dynamic excitations. Advantageously, the
(de-)activation takes place continuously during a specified span of
time, in order to avoid spikes in the energy supply and in the
speed of the continuous belts. In a preferred embodiment, here the
motors can also be connected to a common energy supply, parallel to
one another.
[0026] The drives of the driving rollers can comprise for example
electric motors. In a preferred embodiment, the drives comprise
hydraulic motors that are connected in series by hydraulic lines.
Here, each hydraulic line advantageously connects two adjacent
hydraulic motors. Hydraulic motors are particularly suitable for
use in a device according to the present invention due to their
quiet running, their damping properties, and their high power.
[0027] For the supply of energy, the carrier structure preferably
has a linear guide that can be displaced in the first direction and
on which there is situated an endless rotating feedthrough for the
supply of energy to a drive, connected thereto, of a driving
roller. If the drives comprise electric motors, the linear guide
can be connected by a first line to an inertially stationary
voltage source. Via the endless rotating guide, the electrical
energy is then supplied to one of the electric motors, from which
it is then transmitted to the other drives connected in series
thereto. In the preferred embodiment having hydraulic motors, the
linear guide is connected to an inertially stationary pressure
source in an analogous manner. The hydraulic pressure is fed to a
hydraulic motor in a constructively simple manner via the endless
rotating guide, and from there is transmitted to the other motors
connected in series.
[0028] Alternatively, the supply of energy to the one drive can
also take place via a pre-tensioned line that is inertially
stationary at one side, the pre-tensioning preventing the line from
sagging. For this purpose, for example the line can advantageously
be unwound from an inertially stationary drum against a resetting
torque.
[0029] During the circulation of the belt units in the first
direction, the drive connected to the endless rotating guide
carries the energy supply, with back-and-forth displacement of the
linear guide. During the deflection of the belt units from a
displacement in the first direction to the opposite direction, the
endless rotating guide enables a corresponding rotation of this
drive. Thus, in a constructively simple manner all drives of the
belt units can be supplied with energy from an inertially
stationary energy source.
[0030] Advantageously, the carrier structure comprises a support
structure in order to support the continuous belts of the belt
units. This makes it possible to realize relatively large surfaces
that can accommodate large loads perpendicular to the surface.
[0031] Preferably, this support structure is fashioned in such a
way that a connection between the continuous belt feedthrough and
the drive connected thereto in the second direction, approximately
in the center of the appertaining belt unit, can circulate along
with this belt unit in the first direction. This permits the
surface to be supported over almost its entire width, and is
particularly advantageous if the loads are widely distributed or
concentrated at the edge, as is the case for example with
multi-axle wheeled vehicles. Equally, the connection can also
circulate in the first direction at another location, for example
at the edge of the surface, so that the surface is supported in
particular in the central area, in which the main load is usually
located.
[0032] The conveyor means preferably comprises two circulating
chains, each circulating in the first direction through the action
of at least one drive wheel. In order to avoid, or at least reduce,
the polygon effect that occurs here, the run-in of each chain to
the associated drive wheel can advantageously have a guide surface
in order to guide the chain, said surface essentially comprising
two linear segments that are essentially parallel, two segments,
preferably clothoidal, having changing inclination with constant
curvature, and a circular segment, in such a way that the chain
goes from a first linear segment, in which it runs essentially in
the first direction, with a constant curvature into a first,
preferably clothoidal segment having changing inclination with
constant curvature, and from here goes with constant curvature into
the circular segment, then going from this segment with a constant
curvature into the second, again preferably clothoidal segment
having changing inclination with constant curvature, and from here
goes with constant curvature into the second linear segment. In
this way, the deflection of the individual belt units at the drive
wheel takes place almost without shocks, enabling a particularly
uniform displacement and further reducing the wear on the device
associated with shocks. As is known, a clothoid is a curve in which
the curvature changes in linear fashion with its length, in
particular a curve in which the product of the curve radius and the
curve length is constant.
[0033] Advantageously, each chain can be actuated by a first and a
second drive wheel situated at the beginning or end of the
circulation path of the chain. In order to avoid shear loading of
the belt units, the first and/or second drive wheels of both chains
are preferably each controlled with angular synchronism; electric
motors are particularly well-suited for this.
[0034] Preferably, the drive wheels are fashioned as polygonal
wheels that can enter into positively fitting engagement with bolts
of the respective chain. This enables actuation of the chains with
very little play and with low wear.
[0035] It is equally possible to use toothed belts, rigid chains,
and/or a magnetic linear drive as a conveyor means. The latter
advantageously makes it possible to provide fewer belt units,
because in the idle run phase they can circulate faster. In this
way, it is possible to provide only the number of belt units
required to form the surface on the one hand and in addition to
replace the belt units running out therefrom. To a first
approximation of a continuity equation, the number of belts can be
reduced by approximately half the number of belts required for
complete equipping, divided by the increase in speed in the idle
run phase. Thus, in a device in which the belt units are circulated
in the first direction by a magnetic linear drive and are conveyed
back in the idle run phase at twice the speed, the number of belts
can be reduced by one-fourth (half, divided by twice the speed) in
comparison with full equipping.
[0036] Preferably, each belt unit can comprise a traction device by
means of which the continuous belt can be drawn to a carrier
structure of the belt unit. For example, a magnetically reactive
continuous belt can be drawn using a magnet. Equally, the
continuous belt can also be drawn to the carrier structure by a
partial vacuum created by a vacuum device. This advantageously
compensates lateral forces, in particular ill the first direction,
on the continuous belts, thus also permitting vertical use as an
artificial climbing wall.
[0037] Further objects, advantages, and features result from the
subclaims and from the following exemplary embodiments.
[0038] FIG. 1 shows a device according to an embodiment of the
present invention in a perspective view;
[0039] FIG. 2 shows the device of FIG. 1 in a front view;
[0040] FIG. 3 shows the device of FIG. 1 in a side view;
[0041] FIG. 4 shows a view corresponding to FIG. 2, with belt units
removed;
[0042] FIG. 5 shows an individual belt unit in a perspective
partial view, with a first continuous belt partly removed;
[0043] FIG. 6 shows a drive wheel with sectioned belt units, in a
schematic perspective representation;
[0044] FIG. 7 shows the drive wheel of FIG. 6 in a side view;
[0045] FIG. 8 shows the hydraulic circuit plan of a valve;
[0046] FIG. 9 shows a drive wheel with an actuated chain in a
perspective partial view; and
[0047] FIG. 10 shows a linear guide with an endless rotating
feedthrough for the energy supply.
[0048] FIG. 1 shows a device having a surface displaceable in two
spatial directions according to an embodiment of the present
invention, in a perspective view. The device comprises a carrier
frame 11 that is shown in more detail in FIG. 4.
[0049] As can be seen in FIGS. 6, 7, and 9, a conveyor means 16, in
the form of two link chains, surrounds the carrier frame in a first
direction. Each chain comprises, in a known manner, inner and outer
elements 44, 45, connected to one another in jointed fashion by
bolts 46 (FIG. 9). In order to displace the chains in the first
direction, a first and a second drive wheel 18 each engage in each
chain 16, said drive wheels being fashioned as polygonal wheels and
driven by a first electric motor M10 or M20 or by a second electric
motor M11, M21. Advantageously, first and second electric motors
M10, M20 or M11, M21 are controlled with angular synchronism so as
to avoid shear stress on the device. Preferably, the front drive
wheels (in the direction of displacement) draw the chains, and the
rear drive wheels (in the direction of displacement) rotate along
with approximately the same speed, so that the chains do not have
to transmit any tensile forces in order to overcome the friction of
these rear drive wheels and their electric motors. When the first
direction of displacement is reversed, the first and second drive
wheels exchange their roles as front or rear drive wheels.
[0050] The drive wheels are fashioned as polygonal wheels that can
enter into positive engagement with bolts 46 of the respective
chain.
[0051] A plurality of belt units 20 are fastened permanently or
detachably to the chains, so that the belt units are displaced
along with the chains in the first direction. As is shown in FIGS.
6, 7, for this purpose there are situated on chain elements 44, 45
holding clips 43 with which each belt unit can be brought into
engagement. Here, all possible types of fastening are conceivable,
including in particular screws, locking connections, snap
connections, clamping connections, bayonet locks, or the like.
Advantageously, the connection between the belt unit and the
conveyor means permits a certain rotation about an axis that is
essentially perpendicular to the first and second direction, in
order to compensate manufacturing tolerances and asynchronicities
of the conveyor means.
[0052] In FIG. 5, a belt unit 20 is shown in more detail. It
comprises a first endless or main belt 22 (FIG. 2) that is partly
hidden in FIG. 5. It circulates on the belt unit in a second
direction that is oriented essentially perpendicular to the first
direction, actuated by a first driving roller 23.
[0053] Each first driving roller is actuated by a dedicated drive
that in the exemplary embodiment is fashioned as hydraulic motor
26. This motor drives first driving roller 23 via a tractor belt
24.
[0054] In addition, each belt unit comprises a second continuous or
support belt 21 that is situated on the belt unit parallel to the
first continuous belt and that is driven in the second direction by
a second driving roller 28. The second driving roller is driven via
a tractor belt 25, together with first driving roller 23, by drive
26 of the belt unit in such a way that the first and second
continuous belts have the same speed of circulation.
[0055] In a modification (not shown) of the exemplary embodiment,
first and second driving roller 23, 28 can also be combined to form
a common driving roller.
[0056] The carrier structure comprises a linear guide 71, shown in
more detail in FIG. 10, that is displaceable in the first direction
and on which there is situated an endless rotating feedthrough 72
for the supply of energy to a drive, connected thereto, of a
driving roller. In this way, the energy, for example electrical
power or hydraulic pressure for electric or hydraulic motors 26,
can be transmitted from an inertially stationary energy source,
connected for example to carrier frame 11, to linear guide 71 via a
flexible line that permits displacement in the first direction, and
from there can be transmitted via endless rotating feedthrough 72
to a drive motor 26 that is connected to a rail 74 permanently or
via an elastic component, in particular a spring 77, which itself
is connected permanently or detachably to endless rotating
feedthrough 72.
[0057] As can be seen in FIG. 4, in which the belt units are hidden
for clarity, the carrier structure comprises a support structure 17
for supporting the continuous belts of the belt units, in such a
way that connection 74 (FIG. 10) between the endless rotating
feedthrough and the drive connected thereto in the second
direction, approximately in the center of the appertaining belt
unit, can circulate or travel together with this belt unit in the
first direction. In this way, the first and second continuous belt
of each belt unit can be supported over a wide area, making it
possible to enlarge the surface displaceable in two spatial
directions enough that relatively large movements on the surface
are possible; for example, a person can jump on it. Alternatively,
the narrow area that has to be left open by support structure 17
for the above-mentioned supply of energy can also be provided in a
different area, for example at the edge of the surface.
[0058] Hydraulic motors 26 are connected in series; that is,
starting from the hydraulic motor that is connected to rail 74 and
to which hydraulic pressure is applied via the linear feedthrough
and the endless rotating feedthrough 72, 73, this hydraulic
pressure is supplied to all the hydraulic motors of all the belt
units successively via hydraulic lines between adjacent hydraulic
motors. This permits a very simple, disturbance-resistant supply of
energy, and minimizes the movable parts of the energy chain between
the inertially stationary energy source and the drives circulating
in the first direction.
[0059] As can be seen in particular in FIGS. 7 and 9, the run-in of
each chain to the associated drive wheel has a guide surface 19 in
order to guide the chain, essentially comprising two linear
sections that are essentially parallel, two clothoidal segments 13,
and a circular segment, in such a way that the chain goes from a
first linear segment, in which it runs essentially in the first
direction, with constant curvature into a first clothoidal segment,
and from here goes with constant curvature into the circular
segment, and then goes from this segment with constant curvature
into the second clothoidal segment, and from here goes with
constant curvature into the second linear segment. Here, in the
clothoidal segments the product R(s)s of the curvature radius R(s)
and curve length s is constant, which enables a continuous
transition of the linear segment (radius of curvature R(0)
infinite) at the beginning of the curve (curve length s=0) to the
circular segment having curvature radius or circular radius RE,
avoiding run-in and run-out shocks as well as the polygon
effect.
[0060] In the following, an embodiment of the present invention is
explained in terms of the individual assemblies of the device.
[0061] As stated, the basic construction of the device consists of
carrier frame 11 having a running surface on which belt units 20
are displaced, and that comprises a guide surface 19 in the area of
the drive wheels. The device can be divided into two functional
areas: carrier frame with main drive (11-19) and belt units
(20-41).
[0062] Using a total of four motors M10, M20, M11, M21, the main
drive drives drive chains 16. Belt units 20 are fastened to these
drive chains 16 by holding clips 43. Each belt unit itself consists
of two belts 21 and 22 that are driven via common motor 26.
Construction of the Belt Units
[0063] FIG. 5 shows the construction of the belt unit. First, or
main, belt 22 is partially hidden here in order to show the inner
workings. Main belt 22 is driven by a driving roller 23, and second
or support belt 21 is driven by deflecting roller 28. Support belt
21 here has a significantly smaller constructive height than does
main belt 22. In addition, support belt 21 is realized in such a
way that it terminates flush at the outer side of frame 33. As soon
as a plurality of belt segments 20 are situated next to one
another, there arises a closed surface made up of belts 22, 21.
Deflecting rollers 23 and 28 are connected to drive 26 by drive
elements 24 and 25. The connection can be realized for example as a
toothed belt drive. Here, the gear ratio in each case is chosen
such that the belts are displaced with identical speed. Drive
element 26 is realized as a leak-free hydraulic motor. Given an
arrangement of a plurality of belt units 20, a precise synchronism
or ganging can be achieved through a serial connection of drive
elements 26.
[0064] For the advantageous controlling of the motor, in addition a
proportional hydraulic valve 30 can be used as a bypass, switched
by a sensor 31. As soon as the belt on chain 16 leaves the
horizontal position on the upper side of the device, in the run-in
to deflection 13, the bypass is activated and belts 21, 22 come to
a halt due to friction. This prevents malfunction ("running off" of
belts 21, 22 from the guide) of belt unit 20, for example a halting
in the vertical position at the deflection with simultaneous
driving by motor 26.
[0065] An energy supply provides energy to the belt. This supply is
constructed in such a way as to facilitate the serial arrangement
of belt units 20. The supply of energy takes place at a belt unit
20 that is supplied by flexible supply line 76. The energy is then
successively forwarded in the chain of belt units 20 until the
train again reaches first belt unit 20, which, depending on the
medium, brings the return line into the energy train.
[0066] For the accommodation of lateral forces, belt 21 and 22 is
equipped with suitable guide elements. An advantageous embodiment
here is for example trapezoidal profiles welded onto the underside
of the bell, which slide into correspondingly shaped grooves of the
run surface.
[0067] In order to improve the spatial expansion of the belt and
the dynamic properties connected therewith, the drive element and
the controlling are housed largely within the belt element. On the
remaining free area underneath the support belt, supports 27 are
attached at intervals, which can accept forces with a support
roller 29 held on bearings. As soon as belt unit 20 is situated on
the upper side of the device, these supports are in contact with
running rails 17 of carrier frame 11. In this way, forces of almost
any magnitude exerted by objects on the device can be accepted
without having to reinforce frame 33 of the belt unit; this is very
advantageous with regard to the weight and dynamics of the device.
In addition, the arrangement can be made almost arbitrarily
wide.
[0068] The bypass of drive motor 26 can in addition be constructed
very advantageously, which has a significant effect on the costs
and operating safety. in the proposed advantageous arrangement
shown in FIG. 8, the bypass is activated by a sensor 60. This
sensor can be realized for example as a roller lever valve. As soon
as a sensor is activated, a fluid flows into piston 62, whose speed
of movement is limited by adjustable throttle check valves 61. The
piston actuates a hydraulic valve whose degree of opening is
proportional to the actuation path. In this way, after a switching
process of the sensor the bypass is opened or closed with
adjustable speed, the opening and closing times being settable
independent of one another. This results in a smooth curve of the
line pressure without pressure shocks, resulting in a constant
speed of all belt units 20.
Main Drive Train
[0069] Belt units 20 are connected to main drive train 16 via a
respective holding clip 43. Main drive train 16 is constructed from
inner elements 45 and outer elements 44, which are fastened via
bolts 46 so as to be displaceable. On bolts 46 there are mounted
running wheels 41 that roll on a running surface with deflection.
Holding clip 43 for belt segments 20 is mounted on an element pair
(44 and/or 45). Main drive train 16 is driven by a segmented wheel
18 that engages in bolts 46 on the inner side between a pair of
elements 45. The segmented wheel is advantageously constructed in
such a way that after the engagement has taken place the positive
fit of bolts 46 with wheel 18 is ideal (exact fit, hardening of
segmented wheel 18), and main drive train 16 is automatically
centered by a beveling on the outside of the tooth edges of
segmented wheel 18.
[0070] Run-in 19 is shaped especially in order to avoid the known
polygon effect at chain edges, above all given large spacings. It
also serves to prevent what is known as the lash effect, in which
belt segments 20 have a tendency, given a jump in the curvature of
the running belt, to strike against the adjacent belt segments 20.
The transition 19 from the running surface to the deflection takes
place with a constant curvature. The beginning of the deflection is
advantageously realized as a clothoid 13. In this way, a sudden
jump in acceleration is avoided, and the belt units 20 separate
from one another without shocks. As soon as the clothoid has
inclination and curvature identical to that of the corresponding
circular arc of polygonal wheel 18, deflection 13 goes from the
clothoidal shape to the circular path. With the beginning of the
circular path, the complete contact of a bolt 46 with polygonal
wheel 18 is also created. The run-out is fashioned in the same way
as the run-in. At the transition from the circular path to the
clothoidal shape, bolts 46 become separated from polygonal wheel
18. Subsequently, belt segment 20 is continuously braked in its
rotation about its longitudinal axis, and finally, at the
transition to the linear run surface 19, makes contact without
shocks with belt segment 20 traveling in front of it.
[0071] A precise synchronism of the two main drive trains 16 is
particularly advantageous, because otherwise the entire device may
be destroyed. For this purpose, each of the two main drive trains
16 is equipped with two drive elements M10, M11 or M20, M21. These
drive elements are advantageously fashioned as electric motors
having a gear mechanism and a control unit.
[0072] In order to displace main drive trains 16 in the direction
of drives M10, M20, the following controlling is provided: M10 and
M20 are controlled with angular synchronism, and are held in exact
synchronism by the control unit, using rotary sensors in a closed
control loop. The motors at the opposite side, M11 and M21, are
charged with a constant moment in the running direction that is
sufficient to displace the motors and the gear mechanism themselves
but not to exert relevant forces on the main drive train. The
purpose of this is so that motors M11 and M21 will not be dragged
by main drive trains 16, which would result in increased wear and
destruction. The movement in the opposite direction takes place in
analogous fashion, but the motors are exchanged: M10.fwdarw.M11 and
M20.fwdarw.M21. In order to brake the device, the braking force is
applied by the drive motors that are situated opposite those
required for the acceleration. For example, if, as shown, the
driving is accomplished by M10, M20, then the braking force is
applied by M11, M21, M10, M20 are again charged with a constant
moment in the running direction in order to prevent the gear
mechanism and motors M11, M21 of main drive train 16 from being
driven by the inertia of the moved masses in a manner similar to a
generator. Correspondingly, here the braking force is greater than
the moment at M11, M21.
[0073] As is shown in FIG. 4, the supply of energy 14 takes place
at a belt segment 20 inside carrier structure 11. Belt segment 20
at which the energy is fed in accomplishes the forwarding to other
belt segments. The situation of element 14 takes place as shown in
FIG. 10. On a rail 70 that is connected fixedly to carrier
structure 11 inside the chain of belts, a linear guide 71 slides. A
rotating feedthrough 72 that transfers the energy to endlessly
rotatable element 73 is fastened to this linear guide. The rotating
feedthrough is supplied with energy from energy chain 75, which is
connected at the other end to carrier frame 11. In this element, in
addition to the energies transmitted into 72, vacuum can be fed
through as needed; for example, this vacuum can be used to fix the
belts on 22 on the support. A traction element, for example a
spring 77 between rail 74 and belt unit 20, is fastened to a rail
74. In addition, energy guide elements, for example hydraulic hoses
and cables, are also fastened to rail 74.
[0074] If a belt segment 20 is now displaced, via the above-named
traction element it exerts, in addition to the pre-tension force,
an additional force on rail 74. In order to compensate the
resulting imbalance of forces, elements 71 to 74 are displaced in
such a way that an equilibrium is reestablished. In this way it is
ensured that the supply of energy takes place in an ideal position
at all times.
[0075] Alternatively, the supply of energy can also take place
without linear guide 70, 71 and energy chain 75. In this case, the
rotating feedthrough is situated centrically in carrier structure
11. Element 73 is realized as a drum from which a long energy chain
leads to belt segment 20. Drum 73 is pre-tensioned with a constant
moment by a suitable drive element, and provides that the energy
chain from element 74 to element 20 is always under tension and
does not make impermissible contact with the belts.
Carrier Structure
[0076] Carrier structure 11 is constructed in such a way that it
can ideally accommodate the forces that arise, while at the same
time enabling a supply of energy. FIG. 1 shows the arrangement of
the carrier elements. Here, carrier segments 11a are fixed via
connectors 11b. Braces 11c provide the necessary stability. The
system has a modular construction and can be disassembled quickly,
which facilitates mobile use.
[0077] FIG. 4 shows the carrier structure 11a front view without
main drive chain 16 and belt segments 20. The loads that occur on
the belt segments are accepted via elements 17 and 19. The
cantilever of element 11a is kept as short as possible here. In
addition, the greatest load occurs in the area of guide rails 19,
which load is introduced directly into the stable perpendicular
carriers of 11a. At the same time, due to the opening on the upper
side of two connected elements 11a, sufficient space remains for
the feedthrough of the energy chain.
[0078] The return routing of belt segments 20 takes place in the
interior of carrier segments 11a.
* * * * *