Note: Descriptions are shown in the official language in which they were submitted.
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WEIGHT LIFTING SIMULATOR APPARATUS
FIELD OF THE INVENTION
The present invention relates to weight lifting simulator apparatus for
exercise or
therapeutic use.
BACKGROUND OF THE INVENTION
Weight lifting simulator apparatus of conventional form includes the provision
of
weights giving a resistance loading, which may be varied by selection, for a
user
who activates the apparatus using a gripping handle operating on a cable and
pulley or lever mechanism. It is also known to employ such simulator apparatus
that includes either a resistance arrangement on its own, being either
elastic,
pneumatic or the like, or in combination with weights. Examples of such
apparatus are disclosed in US Patent application publication
No. US 2003/0115955 to Keiser, which comprises a compact resistance unit
that houses a pneumatic cylinder providing resistance through a block-and-
tackle mechanism to a handle operable by a user. US Patent application
publication No. US 2005/0032612 to Keiser describes a combined weight and
pneumatic resistance exercise apparatus. US Patent No. 6,652,429 to Bushnell
discloses an exercise machine with controllable resistance. In most prior art
apparatus control of the resistance level is effected by the use of a simple
valve
in conjunction with an air compressor which is expensive, cumbersome, noisy
and require external power source. All these apparatuses have systems that
allow control of some static inertial effect of weight simulation since the
control
effect depends of the position of the different components of the respective
mechanism. None of these apparatuses includes a control of the dynamic
inertial effect of weight that depends on the speed the different components
move relative to one another during operation of the apparatus, by increasing
the inertial effect thereof, especially during movement of the apparatus.
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Accordingly, there is a need for an improved weight lifting simulator
apparatus,
which provides the facility for a constant application of resistance at any
given
setting.
SUMMARY OF THE INVENTION
It is therefore an object of the present invention to provide an improved
weight
lifting simulator apparatus that solves the above-noted problems.
An advantage of the present invention is that the weight lifting simulator
apparatus includes a typically controllable dynamic inertial effect simulation
of
weight displacement in addition to a static inertial effect; the dynamic
inertia
effect being increased, this increase being dependent on the speed of the
activation movement of the apparatus. Typically, the apparatus enables,
through a relatively simple mechanism, simulation of weight lifting with a
control
of the amount of dynamic inertial effect, from constant force with negligible
inertial effect all along its extension path to a more real inertial effect
feel of the
weight as found in conventional weight lifting apparatuses using real physical
weights.
An advantage of the present invention is that the apparatus is of compact
design and construction using elastic or pneumatic technology, and preferably
compressible elastic fluid technology for the simulation of weight resistance
without the use of active compressor.
Another advantage of the present invention is that the apparatus allows a
ready
control and modulation of the weight resistance and/or the dynamic weight
inertia effect simulation by simple manipulation of the configuration.
According to the present invention there is provided a weight lifting
simulator
apparatus comprising a frame, a guideway pivotally mounted on the frame for
activation by a user, a primary load resistant member having generally opposed
first and second primary ends respectively movably mounted on the frame and
pivotally and adjustably securable to the guideway at a desired position
therealong, at least one secondary load resistant member having generally
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opposed first and second secondary ends respectively mounted in pivoting
fashion in relation to and adjacent the second primary end and connected to a
slider associated with and movable relative to the guideway so as to remain
substantially perpendicular thereto, the primary and secondary load resistant
members being operatively interconnected in such manner as to provide a
generally constant resistance with dynamic weight inertial effect upon
activation
of the guideway by the user, whereby in use upon activation of the guideway
the
user encounters a dynamically reduced resistance for increased weight inertial
effect from both the primary and secondary load resistant members after
initial
activation of the guideway depending on the displacement speed thereof.
In one embodiment, the first primary end is pivotally mounted on the frame and
the second secondary end is pivotally mounted on the slider.
Typically, the primary and secondary load resistant members are fluid
actuatable cylinders, and typically pull-type load resistant members.
In one embodiment, the primary and secondary cylinders are fluidly
interconnected in such manner as to constantly provide a uniform internal
pressure therein.
Conveniently, two secondary cylinders are provided, and mounted in parallel
relative to one another.
In one embodiment, a clamp is provided for the securement of the second
primary end to the guideway.
In one embodiment, a stepped adjustment mechanism is provided for the
securement of the second primary end to the guideway.
Typically, the stepped adjustment mechanism is in the form of a rack,
eventually
arcuate, with a resiliently-loaded detent engageable with the interstices of
the
rack, and the resiliently-loaded detent is remotely operable by means of a
cable
actuable upon the detent.
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Alternatively, the stepped adjustment mechanism includes a scalloped,
typically
arcuate, slot formed in the guideway, a cam-operable roller engageable with a
selected one of the scallops in the slot.
Conveniently, the cam-operable roller is carried on a yoke having a bridge
with
a bridge collar mounted adjacent the second primary end, and a fixed collar
connected adjacent to the first primary end having pivotally mounted thereon a
lever carrying a cam operable upon the bridge collar of the yoke, whereby in
use operation of the lever and the cam moves the cam-operable roller into or
out of engagement with a scallop in the guideway slot.
In one embodiment, the slider associated with the guideway includes at least
one roller or a linear type bearing engageable with the guideway.
Typically, the second secondary end is pivotally mounted on a pivot axis
substantially intersecting a sliding axis of the slider moving relative to the
guideway.
In one embodiment, the secondary load resistant member is further attached to
the primary load resistant member in sliding manner through the agency of a
mount providing for resiliently-biased linear movement and secured to and
adjacent the second primary end so as to further dynamically increase weight
inertial effect from both the primary and secondary load resistant members
after
initial activation of the guideway depending on the displacement speed
thereof.
Typically, the guideway is pivotally mounted on the frame at a pivot axis and
the
linear movement is along a linear movement axis oriented towards the
guideway in a direction away from the pivot axis relative to the first
secondary
end.
Conveniently, the linear movement axis is angularly adjustable relative to the
guideway for adjustment of the dynamically increased weight inertial effect
from
the secondary load resistant member.
In one embodiment, the apparatus further includes a user handle connected to
the guideway for activation thereof by the user.
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Typically, a cable member and pulley arrangement connects the handle to the
guideway.
Alternatively, the handle is mounted on an extension of the guideway extending
longitudinally away from a pivot axis thereof.
5 In other embodiment, the second secondary end is either fixably or
movably
mounted on the slider.
In one embodiment, the first primary end slidably mounted on a guide rail of
the
frame so as to be virtually pivotally mounted on the frame.
In one embodiment, the second primary end is pivotally and adjustably
securable to the guideway along an arcuate guide; and conveniently, the
arcuate guide has a gradually decreasing radii curve shape about a pivot
mounting point of said first primary end when leading away from a neutral
position thereof in which said primary and secondary load resistant members
are generally parallel to one another.
Other objects and advantages of the present invention will become apparent
from a careful reading of the detailed description provided herein, with
appropriate reference to the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
Further aspects and advantages of the present invention will become better
understood with reference to the description in association with the following
Figures, in which similar references used in different Figures denote similar
components, wherein:
Figure 1 is a simplified top perspective view of a weight lifting simulator
apparatus in accordance with an embodiment of the present invention, showing
the main cylinder positioned in a heavy-load simulation in an extended
configuration;
Figure 2 is a partially broken and enlarged perspective view of the embodiment
of Figure 1, showing the main cylinder in a contracted configuration;
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Figure 3 is a view similar to Figure 2, showing the main cylinder in an
extended
configuration, in a light-load simulation;
Figure 4 is a view similar to Figure 3, showing the main cylinder in a
contracted
configuration;
Figure 5 is a simplified side elevational view of another embodiment of the
present invention with the cylinder assembly mounted up side down;
Figure 6 is a partially broken and enlarged side view of the embodiment of
Figure 5;
Figure 7 is a view similar to Figure 6, showing another embodiment of the
present invention;
Figure 8 is an enlarged section view taken along line 8-8 of Figure 7;
Figure 9 is a view similar to Figure 7, showing another embodiment of the
present invention;
Figure 10 is a view similar to Figure 1, showing another embodiment of the
present invention with the main cylinder movably mounted on the fame with a
virtual pivot point;
Figures 11a through 11d are enlarged broken views, showing different
embodiments of the attachment of the secondary cylinder(s) to the slider; and
Figures 12a and 12b are enlarged broken views similar to the embodiment of
Figure 7, schematically showing the relative force required from a user to
position the main cylinder along the guideway away from a neutral position
thererof, with the guideway arcuate guide following a constant radii curve and
a
gradually decreasing radii curve when leading away from the neutral position,
respectively.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
With reference to the annexed drawings the preferred embodiments of a weight
lifting simulator apparatus according to the present invention will be herein
described for indicative purpose and by no means as of limitation. Although
the
following description describes the use of primary and secondary pneumatic
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cylinders, any elastic behavior load resistant members, such as elastic
springs
or the like, could be considered without departing from the scope of the
present
invention.
Referring first to Figures 1 to 4 there is shown a generally rectangular frame
2 of
a weight lifting simulator apparatus 1, a guideway 4, or arm, being pivotally
mounted thereon at pivot 6 on a side limb 8 thereof for rotation about a pivot
axis between two limit angular positions (one position limiting stopper being
the
piston rod 18 fully retracted inside the cylinder 14 as detailed hereinbelow
and
shown in Figures 2, 4, 7, 8 and 9, the other being shown in Figure 9 in dotted
lines). The free end of the guideway 4 remote from its pivot 6 either
pivotally
carries a block-and-tackle arrangement diagrammatically depicted at 10, the
arrangement 10 being connected to a suitable actuating handle 5 (see Figure 5)
via a rope or cable 12, or is provided with a longitudinal extension 4' and
handle
5' (shown in dotted lines in Figure 1) of the guideway 4 away from the pivot
6,
fora user.
A primary load resistant member, typically a pneumatic cylinder 14 is movably,
preferably pivotally, mounted at a first primary end 16 on the frame 2 as
illustrated with its primary second end or piston rod 18 pivotally carrying a
clamp
20, adjacent pivot 19, for registration with the guideway 4 at any desired and
selected position therealong. In this embodiment, twin secondary load
resistant
members, typically pneumatic cylinders 30 are provided and have a first
secondary end pivotally attached to a collar 32 for pivotal connection with
and
adjacent the end of the piston rod 18. The second secondary ends or piston
rods 34 of the cylinders 30 are attached or connected, either fixedly or
movably
(see Figures 11a to 11d and corresponding details hereinbelow) and typically
pivotally mounted, to a yoke in the form of a slider 36 bridging the guideway
4
and being slidable therealong, typically using a linear type bearing or the
like. A
pivot axis 35 of the secondary piston rods 34 is generally perpendicular and
typically as close as possible to the sliding axis of the slider 36 for
increased
smoothness in the sliding motion, as shown in Figures 1 through 9. Preferably,
the pivot axis 35 generally intersects the sliding axis of the slider 36. In
operation, the slider 36 allows the secondary cylinders 30 to remain
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substantially perpendicular to the guideway 4 during pivotal displacement
thereof.
The primary and secondary cylinders 14, 30 are typically fluidly
interconnected,
to generally keep all internal pressures uniform, by suitable hoses 40 which
typically unite in a pressure control or fill/purge valve 42, such as a
typical
bicycle fill valve or the like, to eventually allow selective modification of
the total
amount of fluid, or fluid pressure, inside the cylinders 14, 30. The filling
of the
cylinders 14, 30 could be performed via a conventional manually or power
activated pump. Obviously, more sophisticated pump mechanisms with
predetermined pressure levels could also be considered without departing from
the scope of the present invention; the more fluid there is inside the
cylinders
the more resistive the created force will be.
As shown in Figure 1 the apparatus 1 has the guideway 4 in its maximum
upward angular displacement or extension such that the primary cylinder 14 has
had its piston as "fully extended" as possible by a user employing the block-
and-
tackle 10 and the rope 12, which is accordingly taut. The cylinder 14, which
obviously still has a minimum volume of air therein, is in a heavy load
simulation
with the clamp 20 secured near the free end of the guideway 4 and the slider
36
of the secondary cylinders 30 having moved towards side limb 8 with their
collar
32 locked to the rod 18 to remain substantially perpendicular to the guideway
4.
This relative movement occasions free fluid interflow between the primary and
secondary cylinders 14 and 30 thereby distributing the resistive force and
providing a generally constant resistance to the user. Depending on the weight
of the slider 36, the sliding displacement of the secondary cylinders 30 along
the
guideway 4 dynamically increases the weight inertial effect of the load
simulator;
i.e. the relatively small dynamic load reduction felt by the user, as would be
naturally felt with a real weight being lifted, will be larger if the
displacement
speed of the slider 36 induced by the rotational displacement of the guideway
4
is larger.
Figure 2 shows the cylinder 14 in a contracted (seating) position
corresponding
to a resting configuration of the apparatus 1 ensured by the built-in pressure
inside the cylinders. In the apparatus resting configuration, the rope or
cable 12
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is released by the return stroke of the user with the handle 5 (as shown in
Figure 5) up to an abutment position against a stopper or the like (not shown)
that could also be the handle 5 itself or even protectors thereof that would
be
blocked by the first pulley it encounters or the like. The slider 36 of the
secondary cylinders 30 has moved along the guideway 4 towards the block-
and-tackle 10, and this reciprocating movement is repeated as the user moves
the rope 12 into a heavy load and then into a return or release position.
Figures 3 and 4 show the clamp 20 in a different position nearer to the pivot
6 of
the guideway 4 with the rod 18 extended to a smaller extent than in Figures 1
and 2. The close position of the clamp 20 provides for a smaller lever length
to
the cylinder 14 on the guideway 4, associated with a smaller range of travel
of
the piston in the primary cylinder 14, give a lower resistance weight loading
simulation. Again, the interflow of air between the cylinders with the sliding
of
the piston rods 34 on the guideway 4 provides for a balancing of force that
gives
a smooth and constant application of load resistance with dynamic weight
inertia effect.
Referring now to Figures 5 and 6, the primary cylinder 14 is pivotally
attached to
an upper region 50 of the apparatus 1 and the guideway 4 is pivoted at 6 in a
relatively lower region 51 of the apparatus. The clamp 20 is in the form of a
spring-loaded detent 52 registering and engaging with a rack 54 of arcuate
form
provided in a slot 56 within the guideway 4. The detent 52 is actuable by
means
of a wire or cable 58 and accordingly resetting the detent 52 in a recess of
the
rack will change the resistance loading of the primary cylinder 14 as with the
first embodiment of Figures 1 to 4. The clamp 20 is pivotally carried by an
arm
53 which is attached to the piston rod 18 of the primary cylinder 14. The
slider
36 of the secondary cylinders 30 engages the guideway 4 in the manner shown
in the drawings; the secondary cylinders 30 are connected in a similar manner
to a collar (not shown) pivotally mounted on the piston rod 18.
The guideway 4 carries at the free end remote from its pivot 6 a pulley 60
which
is one of an array 70 of pulleys provided for the apparatus 1 as shown. The
cable 12 is reeved around the pulley 60 and upon appropriate movement of the
cable the guideway 4 is caused to pivot about its mounting at 6. A pull on the
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cable causes tension therein and brings the guideway 4 into a downward path
thus generating resistance via the compressed fluid in the primary and the
secondary cylinders 14, 30 which are balanced due to the fluid flow
therebetween via the hoses 40. The advantage of the arrangement is as
5 previously indicated in relation to the first embodiment. However, the
setting of
the primary cylinder orientation relative to the guideway is fixed by virtue
of the
rack, which provides for predetermined incremental steps to give discrete
modulation.
With reference now to Figures 7 and 8 there is shown a variation on the
10 embodiment illustrated in Figures 5 and 6 in that the guideway 4 is in
two parts
4a and 4b generally parallel to each other; the slot 56 is formed in each part
and
is of scalloped form on its relatively upper margin, each scallop 72 being so
shaped as to accommodate a roller 74 carried on a yoke 76 which embraces
both parts as more clearly can be seen in Figure 8. A bridge piece 78 of the
yoke 76 is mounted on the piston rod 18 also connected to a collar 80 mounted
thereon. A fixed collar 82 is provided on the cylinder 14 and carries an
actuating lever 84 with a cam 86 that abuts the collar 80 when the apparatus 1
is in the resting configuration with primary cylinder 14 in a substantially
contracted configuration, rotation of the lever and thus the cam occasioning
movement of the yoke 76 to engage or disengage the rollers 74 in a respective
scallop 72 as desired to change the setting and to fix the rollers in the
required
setting. The slider 36 comprises spool type rollers 90 which engage the lower
side of each of the parts 4a and 4b as can be seen in Figure 8. As shown in
Figures 7 and 8, the pivot mounting 19 of the piston rod 18 would typically
coincide with the axis of rollers 74 while the pivot 35 of the piston rods 34
would
typically coincide with the rotation axis of the rollers 90. The operation of
this
embodiment is essentially the same as that of the previous embodiment except
that the setting of the primary cylinder is effected by the interengagement of
the
rollers 74 with the scallops 72 in contrast to the rack formation and the
locking
of the setting is secured by the use of a cam operated lever arrangement.
Figure 9 depicts a variation of the embodiment of Figure 7 in terms of the
connection mount between the primary and secondary cylinders 14 and 30.
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The connection 100 provides for a linear displacement of the secondary
cylinder(s) 30 relative to the rod 18 with a resilient bias giving a damping
effect.
In this connection, the connection 100 comprises a slideway bracket 104,
tightly
secured to the rod 18 at 102, holding a pin 106 on which the end 108 of the
cylinder(s) 30 slides reciprocally, as shown by the straight arrow Y, as much
as
possible in a frictionless manner, typically via a linear bearing or the like.
A
spring 110 is provided on the pin 106 and thus gives a bias to the end of the
cylinder(s) 30. Obviously, the end 108 of the cylinder(s) 30 is pivotally
mounted
relative to the pin 106 as shown by arrow X.
The pin 106 has its axis 107 (linear movement axis) that is typically
angularly
oriented towards the guideway 4 in a direction away from the pivot axis
relative
to the cylinder(s) 30, or towards the free end of the guideway 4 when the
latter
is in its limit angular position away from the main cylinder 14, as shown by
angle T of Figure 9 with the limit angular position of the guideway 4 shown in
dotted lines. Obviously, when the angle T is properly set with the main piston
rod 18 connected to the guideway 4 at its far most location relative to the
pivot 6
(in a heavy load configuration, not illustrated), any other subsequent
location of
the piston rod 18 on the guideway 4 would be automatically set, with the
effect
of the connection 100 being the most apparent in that heavy load configuration
where it is expected the most.
The provision of the connection 100 is to further dynamically increase the
weight inertial effect of the load simulator by increasing the simulation of
the
weight reduction feeling occurring during the lifting movement when lifting
real
weight bars, depending on the speed of the movement. The secondary
cylinder(s) 30 always tends to remain generally perpendicular to the guideway
4
while contracting as much as possible, thus having the first secondary end or
cylinder(s) 30 slide toward the spring 110 upon lifting movement because of
the
angle of the pin axis 107. The biasing spring 110 is there to bias this
displacement and prevent any shock that could occur, especially at the end of
the linear displacement path along the pin 106.
Typically, the angular position of the mount connection 100 relative to the
piston
rod 18 can be adjusted, preferably incrementally, via an adjustment mechanism
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102 such as a tightening bolt or the like, to control the additional dynamic
weight
inertia effect of the apparatus 1 provided by this connection 100.
The overall advantage of the present invention is to simulate weight lifting
apparatus by the use of pneumatic cylinders with free interflow of air thus
facilitating the achievement of constancy in terms of resistance.
Referring more specifically to Figure 10, there is shown another embodiment la
of the apparatus of the present invention in which the first primary end 16 of
cylinder 14 is movably, typically slidably and non-pivotally, mounted on an
arcuate guide rail 3 secured to the frame 2. The guide rail 3 provides for
circular displacement of the first primary end about a virtual pivot 16' such
that
the primary load resistant member is virtually pivotally mounted on the frame.
This mounting allow the use of a shorter primary cylinder 14, yet with similar
volume as the long primary cylinder of Figures 1 through 9, i.e. similar
reservoir,
without affecting the weight lifting simulation characteristics of the
apparatus 1a.
In order to vary the dynamic weight inertia effect of the apparatus 1, the
second
secondary ends or piston rods 34 could be connected in different ways to the
slider 36, as shown in Figures 11a through 11d, as examples.
In Figure 11a, the rods 34 are fixedly mounted on the slider 36 via securing
bolts 37a to restrain the dynamic weight inertia effect from the sliding
motion of
the slider 36. In Figure 11b, the dynamic weight inertia effect is slightly
enhanced by the rods 34 being slidably mounted, in a direction typically
parallel
to the slider displacement direction, on the slider 36 via a slot-square shaft
arrangement 37b or the like, the arrangement providing a smooth (not jerked)
sliding.
In Figures 11c and 11d, the rods 34 movably mounted on the slider 36 via
flexible links, such as a rubber-type piece 37c, a helical spring 37d,
respectively,
or the like flexible arrangement, further enhance the dynamic weight inertia
effect to the apparatus 1 from the sliding motion of the slider 36.
Referring now to Figure 12a, there is schematically shown the relative force
Fu
required from a user to position the second primary end (piston rod 18) of the
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primary cylinder assembly 14 along the guideway 4 away from a neutral position
N, with the arcuate guideway slot 56 (or any other arcuate guide or the like)
having a smooth upper margin 57 rollably engaged by the roller 74 whose pivot
axis 19 is further a pin or the like that lockingly engages one of the
different
position holes 75 following a generally constant radii curve C about the first
primary end pivot point 16 when leading away from the neutral position N
wherein the primary and secondary cylinders 14, 30 are generally parallel to
one another (as shown in dotted lines in Figures 12a and 12b), since the
secondary cylinder 30 tends to remain into the neutral position with force Fs.
This user applied force Fu might get significant enough to prevent a young or
weak user from locating the primary piston 14 in position holes 75 at either
ends
of the slot 56. In order to reduce that amount of effort required by the user,
illustrated by smaller force Fu' in Figure 12b, the guideway slot 56' is
preferably
shaped with a gradually decreasing radii curve C', about the first primary end
pivot point 16, when leading away from the neutral position N, as illustrated
in
solid lines (relative to dotted lines) in Figure 12b. This decreasing radii
curved
slot 56', with corresponding position holes 75', essentially compensates for
the
retention force Fs exerted by the secondary cylinder 30 by allowing the
primary
cylinder 14 to contract while the secondary cylinder 30, operatively or
fluidly
interconnected to the primary cylinder 14, is forced to expand and pulls with
force Fp while getting away from the neutral position N.
Depending on the design parameters (actual angles and the like), the force Fp
exerted by the primary cylinder 14 could happen to be slightly larger than the
resistive force Fs from the secondary cylinder 30 such that the user's force
Fu'
could be negative (in the opposite direction than illustrated in Figure 12b).
It is
to be noted that the neutral position N could be anywhere along the arcuate
guide, or even away therefrom (virtually out of the guideway 4), and not
necessarily at its geometrical center. Also, as it would be readily understood
by
one skilled in the art, the gradually decreasing radii curve C' could be
formed
with a constant smaller radii about a point located closer to the guideway 4
than
the first primary end pivot point 16.
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Although the above description refers to resistance provided by pull-type
cylinders (or other pull-type load resistant members), it would be obvious to
one
skilled in the art to use push-type cylinders (or other push-type load
resistant
members) without departing from the scope of the present invention.
In order to further control the dynamic weight inertia effect response of the
apparatus 1, some weight (not shown) could be selectively added /removed to
the slider 36 or rollers 90 of Figures 1 to 4 since the gravity effect works
in the
same direction as the sliding movement direction of the secondary second end
or piston rod(s) 34 on the guideway 4. Additionally, when the guideway 4 is
below the cylinders 14, 30 as in Figures 5 to 9, some hanging weight W or the
like biasing force (as shown in dotted lines in Figure 7) could be even
connected
to the slider 36 to reorient the resulting gravity effect in the same
direction as
the sliding inertial effect of the piston(s) 34 on the guideway 4 by
counteracting
the direct effect of gravity on the slider 36 that would otherwise tend to
generate
some shuddering of its sliding movement.
Although the present weight lifting simulator apparatus has been described
with
a certain degree of particularity, it is to be understood that the disclosure
has
been made by way of example only and that the present invention is not limited
to the features of the embodiments described and illustrated herein, but
includes all variations and modifications within the scope of the invention as
hereinafter claimed.
