OBJECT OF THE INVENTION
[0001] The present invention falls within the technical field of gymnastic apparatus for
strengthening muscles, more specifically those apparatus comprising resistant devices
with rotating bodies, and refers in particular to a compact muscle training device
based on resistance to a traction force exerted by inertia discs and which can be
used either by a single user or by two users simultaneously.
[0002] More specifically, the present invention relates to a training, toning, muscle building
and rehabilitation device for pulling resistance based on inertia discs or rings arranged
on a rotating shaft. The device further comprises a grip handle, a transmission element
for multiplying the revolutions of the shaft, and a connecting cord which is solidly
linked at one end to a conical reel for driving the transmission.
BACKGROUND TO THE INVENTION
[0003] During the development of bodybuilding exercises, two phases of movement can be differentiated:
a concentric or positive phase, in which the muscle insertions are brought closer
together and the movement goes against gravity, so that the muscle is shortened or
concentrated when contracting, and an eccentric or negative phase, where the muscle
insertions are distanced and the movement is generated in favour of gravity, so that
the muscle continues contracted, but lengthens.
[0004] Although the muscle is contracted in both phases, they are contractions with different
effects. The main difference lies in the fact that eccentric contraction is more efficient
from a neuromuscular point of view, because this lengthening produces a greater activation
of actin-myosin bridges, generating a greater muscle contraction. Eccentric contractions
also have a lower metabolic demand and produce greater hypertrophy, which makes them
very effective when it comes to gaining muscle. On the downside, it is worth mentioning
that they are very aggressive for muscle and connective tissue, and if performed inappropriately
can cause injuries.
[0005] Within the technical field of gymnastic apparatus for muscle development, a plurality
of devices are known. For example, the international
PCT application with publication number WO2015019118 discloses a device for providing constant resistance values against displacement.
The device comprises a cylinder connected to a cone or cam or variable diameter pulley,
which engages and balances the preselected resistance value of one or more elastic
means, such as springs, on one side (cylinder side) by the variable torque generated
by an externally applied constant force, and on the other side (cone or cam or variable
diameter pulley side) by appropriately varying the geometrical characteristics defining
the torque, including radii, distances or angles.
[0007] On the other hand, small inertial devices are also known. For example, the US patent
with
publication number US2009093350 refers to a transportable sports training and rehabilitation system, based on a pulling
body consisting of a handle, an inertia motor or discs and a cylindrical coil in which
a rope is picked up and released, which is hooked at the opposite end to a point,
which can be a part of the user's own body or another person. This system has two
handles or attachment points, making it possible to reverse the active end from which
the force is exerted.
[0008] Likewise, document
US3841627 discloses a transportable sports training and rehabilitation system comprising two
pulling bodies, one of which integrates, in addition to a handle, an inertia disc
and a cylindrical coil in which a rope is picked up and released, which is hooked
at its opposite end to the second handle.
[0009] However, currently existing devices comprise inertia elements of high weight and
dimensions, which also limit the versatility of such a device, not allowing it to
adapt to different forces and types of shooting.
DESCRIPTION OF THE INVENTION
[0010] The object of the invention consists of a compact inertial device for muscle training,
which is basically made up of a pulling body and a transmitter cord or belt, which
is solidly linked at one end to the pulling body, while it can be attached at the
opposite end to a fixed point or to a fastening element.
[0011] The pulling body in turn consists of a rotating main shaft, to the ends of which
inertia elements, preferably inertia discs, are solidly attached. A reel, on which
the rope is wound, is mounted solidly and coaxially on the main shaft. In the preferred
embodiment of the device, the reel is conical, and one end of the rope is solidly
attached to its smaller diameter base. The pulling body also incorporates an epicyclic
or planetary gear, the central gear of which is solidly mounted on the main shaft,
with the interposition of a torque-limiting clutch.
[0012] An outer casing surrounds and contains the above-mentioned elements of the pulling
body. This housing has an eyelet-type through-hole opening through which the rope
is taken up and released during winding and unwinding on the reel, and a coupling
element, intended to house a handle for gripping the pulling body for manual operation
by a user.
[0013] The rotary motion of the reel, driven by the rope, is transferred to the inertia
discs via the planetary gearing, with a transmission ratio that causes the inertia
disc to rotate "R" turns with a single turn of the reel.
[0014] The device is based on the "flywheel training" devices known as inertial pulley training,
but differs from them thanks to its reduced size and weight, due to the fact that
it has a high-capacity "R" ratio speed multiplier gear internally, which allows the
inertia discs to rotate R times more than the devices without planetary gearing. As
a result, the apparent moment of inertia of the discs is R
2 compared to that of an ungeared device.
[0015] Thus, with inertia discs of very small dimensions, but rotating at many revolutions,
the same inertia is achieved as with the large discs commonly used in current "flywheel
training" devices, which means a great reduction in material, transport and storage
costs. These smaller inertia discs also lower the centre of mass and the volume of
the device, allowing for much lower, lighter and more economical fixture platforms
than current device platforms.
[0016] The main advantage of a conical rope reel is that, when starting to unwind the rope,
the pulling force required is lower, as it starts to unwind from the part with the
largest diameter. The resistance exerted by the reel, and therefore the pulling force
required to unwind the rope, increases progressively as the radius of the cone decreases.
Likewise, the conical reel facilitates the correct winding of the rope when it is
reeled in.
[0017] In order for the user to use the device, he must initially sufficiently pre-load
the conical reel by winding onto it a quantity of the transmitter rope, immobilise
this rope by means of a ratchet, and fix the opposite end of the rope, on which an
anchoring element is located, to a static point against which the opposite pull is
to be made.
[0018] The device allows both individual use and shared use. In individual use there are
two modes of operation: in the first mode, a single user operates the device through
the pulling body, the rope being attached at one end to a static element through the
anchoring element, so that the pulling body held by the user moves and the opposite
end of the rope remains fixed. Alternatively, in the second mode, the pulling body
is held anchored by an attachment to a static element in the environment and the user
pulls on the free end of the rope by means of a handle linked to the anchoring element.
[0019] In the case of shared use, two users, one operating the pulling body and the other
holding the free end of the rope by means of a handle linked to the anchorage element,
simultaneously pull the transmitting rope in opposite directions, so that both users
share the efforts according to the pulling force applied.
[0020] In the case of individual use of the device, and with the device already preloaded,
the exercise starts with a pulling phase or concentric phase, in which the user pulls
the pulling body through the handle by means of a concentric muscular contraction
in which his muscle is shortened. The transmitter rope begins to unwind, rotating
the conical reel on which it is wound, which in turn rotates the main shaft on which
it is solidly mounted. As mentioned above, as the main shaft is linked to the central
gear of the planetary gear, the inertia element rotates at a speed "R" times greater
than that of the bevel spool, "R" being the reduction ratio.
[0021] In this pulling phase, the user makes a physical effort to pull the rope by means
of which a progressive acceleration is obtained, both in the movement of the device
and in the angular acceleration of the inertia discs. As a result, the inertia discs
themselves are loaded with angular momentum, and this phase ends when the user reaches
the final position of this phase of the exercise, corresponding to the maximum pulling
distance.
[0022] The next phase of the exercise, known as the intermediate dead centre phase, begins
when the transmitter rope has been fully unwound from the conical reel, which stops
rotating. At this point, the inertia discs are fully loaded to their maximum angular
velocity, and continue to rotate in the same direction.
[0023] The discs, rotating at their maximum speed, drag the planetary gear and this, in
turn, drag the conical reel, which continues to rotate in the same direction. The
rope begins to wind around it, starting at the end with the smallest radius, and in
the opposite direction to the previous one, thus beginning the collection or eccentric
phase, in which the user must make an eccentric muscular effort to hold the rope so
that the reel slows down and stops at the same point at which the exercise began.
Thus, the length of rope wound on the reel determines the total exercise distance
to be performed.
[0024] In the last phase of the exercise or end dead centre phase, the main shaft stops,
as well as the gear and the reel to which it is solidly linked, the value of the angular
velocity of the inertia discs being equal to zero. However, the bevel spool is sufficiently
loaded with rope to allow the user to restart a new exercise in the pull or concentric
phase, except that the shaft and gearing will rotate in the opposite direction on
this occasion.
[0025] In the case of simultaneous use of the device by two users, the same sequence of
the above-mentioned four phases is maintained, but with the difference that one of
them holds one end of the rope through a handle linked to the coupling element while
the other grips the pulling body through the handle, in order to pull in the opposite
direction.
DESCRIPTION OF THE DRAWINGS
[0026] In order to complement the description being made and in order to assist in a better
understanding of the features of the invention, in accordance with a preferred example
of a practical embodiment thereof, a set of drawings is attached hereto as an integral
part of the said description, in which the following is illustratively and non-limitingly
depicted:
Figure 1.- Shows a front perspective view of the pulling body and the rope of the
inertial device.
Figure 2.- Shows a rear perspective view of the pulling body.
Figure 3.- Shows a detail view of a cross-section of the pulling body.
Figure 4.- Shows a detailed exploded view of the drawbar body.
Figure 5.- Shows a detail view of the ratchet for the rope of the device.
Figure 6.- Shows a view of the device in individual use according to a first option.
Figure 7.- Shows a view of the device in individual use according to a second option.
Figure 8.- Shows a view of the device in shared use.
Figure 9.- Shows a detail view of a support platform.
Figure 10.- Shows a detail view of the device in use with an incorporated pulley.
Figure 11.- Shows a view of the device in individual use according to a third option.
PREFERRED EMBODIMENT OF THE INVENTION
[0027] A detailed explanation of an example of a preferred embodiment of the subject matter
of the present invention is given below with the aid of the figures referred to above.
[0028] The described compact inertial muscle training device, shown in figure 1, basically
consists of a pulling body (1) and a transmitter rope (2), which is solidly linked
at one end to the pulling body (1), from which it is wound and unwound.
[0029] The pulling body (1), the exploded view of which is shown in figure 4, comprises
an external casing (3) inside which is housed a transversely oriented rotating main
shaft (4). A central gear of a planetary gear (5), which in turn comprises external
gears or planets, is solidly coupled to this main shaft (4).
[0030] Likewise, an inertia element (6), consisting in this case of an inertia disc, is
solidly coupled to said main shaft (4). In the preferred embodiment described here,
the opposite end of the main shaft (4) incorporates an additional inertia element
(7), consisting of another inertia disc solidly linked through its centre to said
main shaft (4), without the interposition of any type of intermediate gear or multiplier
element.
[0031] Mounted solidly and coaxially on a central sector of the main shaft (4) is a reel
(8), which in the preferred embodiment described here is a conical reel, which in
turn has a sector of smaller diameter, to which one end of the rope (2) is solidly
attached. This rope (2) is automatically wound and unwound on the reel (8), thus producing
a rotation on the main shaft (4) on which the reel (8) is solidly mounted.
[0032] The inertia element (6) accumulates rotational energy from the rotation of the main
shaft (4). As the device incorporates the planetary gear (5), the rotational energy
transmitted by the main shaft (4) is multiplied in the planetary gear (5) before being
transmitted to the inertia element (6), to which it is solidly coupled. Thus, with
an inertia element (6) of small dimensions, high values of moment of inertia are achieved
thanks to the intermediate action of the planetary gear (5).
[0033] In the preferred embodiment described here, the planetary gear (5) used has a transmission
ratio of 13,5, so that one revolution of the spool (8) causes the inertia element
(6) to rotate 13,5 turns.
[0034] The casing (3) includes a through opening (9) through which the rope (2) passes for
its deployment and retraction on the reel (8), as well as a hook (10) which projects
from the casing (3) in the vicinity of the through opening (9). The casing (3) also
comprises a coupling (11) for temporary attachment of the pulling body (1) to various
external elements. For example, as shown in Figures 1 to 4, a grip handle (12) is
temporarily attachable to said coupling (11) for manual actuation of the pulling body
(1).
[0035] In the preferred embodiment of the device, the coupling (11) consists of a prominent
sector (13) of quadrangular geometry starting from the casing (3), which has a groove
(14) that surrounds the prominent sector (13) perimetrically, designed to house the
corresponding couplings of the handle (12) or of a fastening element (15) in which
it is desired to immobilise the pulling body (1), as illustrated in figure 7.
[0036] The device also incorporates a ratchet (16), shown in detail in figure 5, which can
be attached to the rope (2) for adjusting the length that can be rewound and unwound
on the reel (8). As can be seen in the aforementioned figure 5, the ratchet (16) has
a through hole (17) for coupling an anchoring element, such as a carabiner, which
allows connection to external elements such as a handle (18), shown in figure 8, which
allows it to be gripped by a second user. The ratchet (16) also incorporates a latching
ring (19).
[0037] It is also envisaged that a pulley (20) is incorporated into the rope (2) to increase
the pulling resistance, this pulley (20) being particularly suitable for performing
exercises involving the work of large muscle groups, such as squats or weightlifting,
without the need to modify the inertia elements (6, 7). For this purpose, the rope
(2) must pass through the pulley (20) and return to the pulling body (1), as illustrated
in figure 10, so that the ratchet (16) is fixed to it by means of a carabiner that
can be inserted into the hook (10).
[0038] It is also envisaged that a number of additional elements will be incorporated to
improve and add functionalities to the device. For example, first of all, it is envisaged
to incorporate a safety element to prevent entrapment and return strokes at the start
of the rope retraction phase (2). This element consists in its preferred version of
a force limiting clutch, consisting of a pre-calibrated spring and two opposing wheels
which disengage the main shaft (4) from the central gear of the planetary gear (5),
in the event of exceeding a pre-established limit force value.
[0039] It is also foreseen the additional incorporation of an externally operable gear change,
linked to the central shaft (4) and designed to vary the transmission ratio of the
planetary gear (5) to obtain different previously established reduction ratios. Optionally,
it is also envisaged the inclusion of a remotely operated brake for blocking the rotation
of the inertia element (6) and, if applicable, the additional inertia element (7),
in the final dead centre phase, which allows the user to carry out additional isometric
(static) exercises, thus increasing the versatility of the device.
[0040] It is also possible to incorporate electronic elements to increase the performance
of the device. For example, a revolution counter consisting of an electronic module
that detects, by means of a sensor, preferably optical, the revolutions and direction
of rotation of the reel (8), in order to subsequently analyse the work curves and
extract parameters such as caloric consumption, time, speed, force, performance, and
other parameters. It is also foreseen to add a wireless transmitter connected to the
lap counter to send the data collected by it to a mobile device equipped with a computer
application that acts as an operational interface with the user.
[0041] It is also envisaged that various elements for attaching the pulling body (1) to
the device will be incorporated into the device to enable various types of exercises
to be carried out. For example, a support platform (21), shown in figure 6, equipped
with elements for coupling with the coupling (11), and designed to support the feet
during the execution of exercises such as squats or weightlifting. In its preferred
embodiment, illustrated in figure 9, the platform (21) is foldable and has a curved
geometry face, with a central sector higher than the perimeter edges.
[0042] It is also envisaged that additional inertia discs can be temporarily attached to
the main shaft (4) by means of bolts or similar quick coupling means.
[0043] Figures 6, 7, 8 and 11 show the device in different uses, both individual use and
shared use, which show its great versatility, as indicated in the description.
1. A compact inertial muscle training device comprising:
- a pulling body (1), further comprising:
- a rotating main shaft (4),
- a reel (8) mounted solidly and coaxially on the main shaft (4), and
- an inertia element (6) solidly linked to one end of the main shaft (4) for accumulation
of kinetic energy from the rotation of the main shaft (4), and
- a drive rope (2), attached at one end to the reel (8), which can be rewound and
unwound on the reel (8),
the inertial device being
characterised in that it additionally comprises a planetary gear (5) which in turn comprises a central
gear linked solidly to the main shaft (4) for multiplication of the transmission speed
from the main shaft (4) to the inertia element (6).
2. Inertial device according to claim 1, wherein the reel (8) is a conical reel having
a sector of smaller diameter to which one end of the rope (2) is solidly attached.
3. Inertial device according to claim 1 wherein the pulling body (1) additionally comprises
an external casing (3) comprising in turn:
- a through opening (9) for passage of the rope (2), and
- a coupling (11).
4. Inertial device according to claim 3, wherein the casing (3) additionally comprises
an attachment hook (10).
5. Inertial device according to claim 3
characterised in that the coupling (11) comprises:
- a prominent section (13) projecting from the casing (3), and
- a groove (14) that surrounds the prominent area (13) perimetrically.
6. Inertial device according to claim 3, characterised in that it incorporates a handle (12) which can be temporarily inserted into the coupling
(11) for gripping the pulling body (1).
7. Inertial device according to claim 1, characterised in that it additionally comprises a ratchet (16) attachable to the rope (2) for adjusting
the length of the rope (2) windable and unwindable on the reel (8).
8. Inertial device according to claim 7
characterised in that the ratchet (16) comprises
- a through hole (17) for attachment of an anchor element, and
- an attachment ring (19) for attaching a pulley.
9. Inertial device according to claim 1, characterised in that it incorporates a pulley (20) linkable to the rope (2) to increase the pulling resistance.
10. Inertial device according to claim 3, characterised in that it incorporates a support platform (21) linkable to the coupling (11) for fixing
the pulling body (1).
11. Inertial device according to claim 10 characterised in that the platform (21) is foldable.
12. Inertial device according to claim 3 characterised in that it additionally comprises a fastening element (15) linkable to the coupling (11)
for immobilisation of the pulling body (1).
13. Inertial device according to claim 1, characterised in that it incorporates a force limiting clutch for decoupling the main shaft (4) from the
central gear of the planetary gear (5).
14. Inertial device according to claim 13, characterised in that the force limiting clutch consists of a pre-calibrated spring and wheels facing the
main shaft (4).