U.S. patent application number 11/384380 was filed with the patent office on 2007-09-27 for actuator for controlling inclination of treadmill and inclination control device of treadmill.
Invention is credited to Seon-Kyung Yoo.
Application Number | 20070225126 11/384380 |
Document ID | / |
Family ID | 38534205 |
Filed Date | 2007-09-27 |
United States Patent
Application |
20070225126 |
Kind Code |
A1 |
Yoo; Seon-Kyung |
September 27, 2007 |
Actuator for controlling inclination of treadmill and inclination
control device of treadmill
Abstract
The present invention provides an inclination control device of
a treadmill comprising: a pair of support members pivotally
connected with at least one first hinge at the track part for
extending from the track part to the ground; a pair of housings
having a housing hinge respectively for being pivotally connected
with each of the second hinge at the support members, and having
female thread; a pair of screw rod engaging respectively with the
female thread of each of the housing so as to be extruded from or
inserted into by relative rotation therebetween; a pair of driving
pulleys combined with each of the screw rod for rotating together
with the screw rod; a belt engaging with the driving pulleys; a
pinion engaging with the belt for transmitting a driving force via
the belt to the driving pulleys; a motor for letting pinion rotate;
and a bracket for rotatably fixing the pinion and the driving
pulleys, and having a pair of bracket hinges on its both sides to
be pivotally combined with each of the third hinges of the track
part, whereby the first hinge, the second hinge and the third hinge
form a three-linked structure so as to stably support the impact
and/or load from a user's running in addition to enhance durability
and to save the manufacture cost.
Inventors: |
Yoo; Seon-Kyung; (Seoul,
KR) |
Correspondence
Address: |
WENDEROTH, LIND & PONACK, L.L.P.
2033 K STREET N. W.
SUITE 800
WASHINGTON
DC
20006-1021
US
|
Family ID: |
38534205 |
Appl. No.: |
11/384380 |
Filed: |
March 21, 2006 |
Current U.S.
Class: |
482/54 |
Current CPC
Class: |
A63B 22/0235 20130101;
A63B 22/0023 20130101 |
Class at
Publication: |
482/054 |
International
Class: |
A63B 22/02 20060101
A63B022/02 |
Claims
1. An actuator for controlling the inclination of the track part of
a treadmill comprising: a motor; a pinion rotatably driven by the
motor; a belt formed to transmit the driving force from the pinion;
a pair of driving pulleys engaging with the belt so as to receive
the driving force from the pinion; a pair of screw rod combined
with each of the driving pulley for rotating together with each of
the driving pulley; and a pair of housings having female thread for
engaging with each of the screw rod; wherein a pair of screw rods
are simultaneously extruded from or simultaneously inserted into
each of the housing by the same length.
2. The actuator for controlling the inclination of the track part
of a treadmill as claimed in claim 1 further comprising: at least
one idler pulley engaging with the belt; wherein the belt is
engaged with the pinion, the idler pulley, and the driving pulleys
for transmitting the driving force from the pinion to the driving
pulleys.
3. The actuator for controlling the inclination of the track part
of a treadmill as claimed in claim 1, wherein the pinion, the idler
pulley, and the driving pulleys has at least one groove on their
sides so as to engage with the protuberances periodically formed on
the belt.
4. The actuator for controlling the inclination of the track part
of a treadmill as claimed in claim 2 further comprising: a bracket
for rotatably fixing the pinion, the idler pulley and the driving
pulleys; and bracket hinges formed at the both sides of the
bracket; housing hinges formed at each of the housings.
5. An inclination control device for a treadmill having at least
one track part comprising: at least one support member pivotally
connected with at least one first hinge at the track part for
extending from the track part to the ground; and at least one
extendable rod pivotally connected with at least one second hinge
which moves together with the support member, and pivotally
connected with at least one third hinge of the track part which is
located apart from the first hinge at the track part; wherein, the
inclination of the track part is controlled by the extension or the
contraction of the extendable rod.
6. The inclination control device for a treadmill as claimed in
claim 5, wherein the support members are formed as a pair for
pivotally being connected with a pair of the first hinges at the
track part, and the extendable rods are formed as a pair for
pivotally being connected with a pair of the third hinges at the
track part.
7. The inclination control device for a treadmill as claimed in
claim 6, wherein a pair of the support members include a traverse
member which connects the support members each other, and the
second hinges are formed as a pair at the support members or at the
traverse member for pivotally being connected with a pair of the
extendable rods.
8. The inclination control device for a treadmill as claimed in
claim 7, wherein a pair of the extendable rods include a pair of
housings having a housing hinge respectively for being pivotally
connected with each of the second hinge, and having female thread;
and a pair of screw rods engaging respectively with the female
thread of each of the housing so as to be extruded from or inserted
into each of the housing by relative rotation therebetween; and,
further comprising: a pair of driving pulleys combined with each of
the screw rod for rotating together with the screw rod; a belt
engaging with the driving pulleys; a pinion engaging with the belt
for transmitting a driving force via the belt to the driving
pulleys; a motor for making the pinion rotate; and a bracket for
rotatably fixing the pinion, and the driving pulleys, and having a
pair of bracket hinges on its both sides to be pivotally combined
with each of the third hinges; wherein one of the first hinges, one
of the second hinges, and one of the third hinges form hinges of
three-link structure.
9. The inclination control device for a treadmill as claimed in
claim 8, wherein the screw rods integrally rotate with each of the
driving pulley respectively.
10. The inclination control device for a treadmill as claimed in
claim 8, further comprising: at least one idler pulley rotatably
fixed to the bracket for engaging with the belt; wherein the belt
is engaged with the pinion, the idler pulley, and the driving
pulleys for transmitting the driving force from the pinion to the
driving pulleys.
11. The inclination control device for a treadmill as claimed in
claim 10, wherein the pinion, the idler pulley, and the driving
pulleys have at least one groove on their sides so as to engage
with the protuberances periodically formed on one side of the
belt.
12. The inclination control device for a treadmill as claimed in
claim 8, further comprising a roller formed at the end of each of
the support member which is contact with the ground.
13. The inclination control device for a treadmill as claimed in
claim 8, wherein the second hinges are formed within the range
between 0.1 L to 0.5 L from one end contacted with the ground, when
the length of the support member is L.
14. The inclination control device for a treadmill as claimed in
claim 8, wherein a pair of the extendable rods include a pair of
housings having a housing hinge respectively for pivotally
connecting with each of the second hinge, and having female thread;
and a pair of screw rods engaging respectively with the female
thread of each of the housing so as to be extruded from or inserted
into each of the housing by relative rotation therebetween; and,
further comprising: a pair of driving gears combined with each of
the screw rod for rotating together with the screw rod; at least
one pair of intermediate gears engaging with the driving gears; a
pinion gear engaging with the intermediate gears for transmitting a
driving force via the intermediate gears to the driving gears; a
motor for making the pinion gear rotate; and a bracket for
rotatably fixing the pinion gear, the intermediate gears and the
driving gears, and having bracket hinges on its both sides for
being pivotally connected with each of the third hinges; wherein
one of the first hinges, one of the second hinges, and one of the
third hinges form hinges of three-link structure.
15. An inclination control device for a treadmill having at least
one track part, comprising: a pair of support members pivotally
connected with a pair of first hinges at the track part for
extending from the track part to the ground; a pair of housings
having a housing hinge respectively for being pivotally connected
with a pair of second hinges at the support members, and having
female thread; a pair of screw rod engaging respectively with the
female thread of each of the housing so as to be extruded from or
inserted into by relative rotation therebetween; a pair of driving
pulleys combined with each of the screw rod for rotating together
with the screw rod; a belt engaging with the driving pulleys; a
pinion engaging with the belt for transmitting a driving force via
the belt to the driving pulleys; a motor for letting pinion rotate;
and a bracket for rotatably fixing the pinion and the driving
pulleys, and having a pair of bracket hinges on its both sides to
be pivotally combined with a pair of the third hinges at the track
part; wherein the third hinges are apart from the first hinges
respectively, and wherein one of the first hinges, one of the
second hinges and one of the third hinges form a three-linked
structure.
16. The inclination control device for a treadmill as claimed in
claim 15, wherein the screw rods are integrally rotate with each of
the driving pulley respectively.
17. The inclination control device for a treadmill as claimed in
claim 15, further comprising: at least one idler pulley rotatably
fixed to the bracket for engaging with the belt; wherein the belt
is engaged with the pinion, the idler pulley, and the driving
pulleys for transmitting the driving force from the pinion to the
driving pulleys.
18. The inclination control device for a treadmill as claimed in
claim 17, wherein the pinion, the idler pulley, and the driving
pulleys have at least one groove on their sides so as to engage
with the protuberances periodically formed on one side of the
belt.
19. The inclination control device for a treadmill as claimed in
claim 15, further comprising a roller formed at the end of each of
the support member which is contact with the ground.
20. The inclination control device for a treadmill as claimed in
claim 15, wherein the second hinges are formed within the range
between 0.1 L to 0.5 L from one end contacted with the ground, when
the length of the support member is L.
Description
BACKGROUND
[0001] 1. Field of the Invention
[0002] The present invention relates to a treadmill, more
particularly, to an actuator for stably controlling an inclination
of the track part of a treadmill and an inclination control device
of a treadmill.
[0003] 2. Discussion of Related Art
[0004] A treadmill known as a running machine is widely used
indoors such as at home or in a sports center because it allows a
user to effectively exercise by working or running on its endlessly
rotating track belt even in the narrow space. In view that a user
can exercise indoors using treadmill even in the cold winter, the
demand for treadmills is recently drastically increasing due to the
advantages of its safety and convenience because.
[0005] By using a treadmill, the user thereof can strengthen the
cardiopulmonary function and muscles of legs, and can control
weight by consuming calories efficiently while running or walking
on the treadmill. To maximize this exercise effect, a treadmill
with an inclination control device came to be lately produced.
[0006] More specifically, a treadmill generally comprises a track
part on which user put their feet for running or walking, and an
inclination control device for supporting the track part and to
control the inclination.
[0007] As illustrated in FIGS. 1 and 2, the conventional treadmill
comprises a track part 10 on which user run or walk, a support part
20 located at a bottom of the treadmill for controlling the
inclination of the track part 10 while sustaining the load or
impact transmitted from the track part 10.
[0008] The track part 10 has a support frame 11 which upholds
weight of user; a belt rotating endlessly, which enables a user to
run or walk continuously on the upper side of the track part 10; a
pair of rollers 13 supporting both sides of the belt 12; a motor 14
as a driving unit for driving making one of the rollers 13 rotate;
and connection part 15 linked with the actuator 30.
[0009] The support part 20 includes a base frame 21 installed on
the ground, and a support member 22, having its one end fixed to a
base frame 21 and the other end 22a pivotally connected to a track
part 10.
[0010] The actuator includes a extendable rod 32, of which one end
32a is pivotally connected to a link member 15 of the track part
10, and of which the other end is pivotally connected to a base
frame 21; and a driving part 31 to control the length of the
extendable rod 32 by extending or contracting the extendable rod
32.
[0011] The above conventional treadmill controls its inclination of
the track part 10 by means of extending or contracting the
extendable rod in the direction of 30a. In this case, the load or
impact of user is concentrated on the part where user put their
foot apart from the other end 22a of a fixed member by d1. That is,
The load and/or impact is concentrated on the front part of the
track part 10, and thus the load Fa of the actuator 30 will be
obtained by the following equation in condition that the track part
10 is parallel to the ground. Fa'=F Equation 1
[0012] In general, since d2 is designed smaller than d1, the load
Fa' applied on the actuator 30 is calculated by user's load F.sub.1
amplified by d1/d2. Besides, the actuator get more moment due to
user's load F.sub.1 generated from exercise on the track. The
conventional treadmill accordingly needs a big actuator to endure
the load and it result in an unnecessary increase of manufacture
costs and power consumption.
[0013] Also, it is not desirable to install a big actuator in the
narrow space between a track part 10 and a base frame 21, from view
that a user feels safe when the distance between the base frame 21
and the track part 10 is as short as possible. As a solution for
this problem, it can be considered that the actuator 30 is
installed at both sides of the track part as a pair. However, if
two actuators 30 are not exactly controlled with the same extended
or the same contracted length, it causes to have a problem that
track part 10 is widthwise inclined even by the small amount,
whereby the user feels unstable and uncomfortable.
SUMMARY OF THE INVENTION
[0014] The present invention has been made in view of the above
and/or other problems, and it is an object of the present invention
to provide with an actuator for controlling an inclination of the
track part of a treadmill, which is capable of stably controlling
the inclination of the track part by simultaneously contracting or
simultaneously extending a pair of extendable rods.
[0015] Another object of the present invention is to provide an
inclination control device of a treadmill, which minimizes the load
and moment on the extendable rod of the actuator for controlling
the inclination of the treadmill thereby enhancing durability as
well as efficiently reducing the manufacturing cost.
[0016] In order to achieve the above objects and another aspect of
the present invention, the present invention provides an actuator
for controlling the inclination of the track part of a treadmill
comprising: a driving unit; a pinion rotatably driven by the
driving unit; a belt formed to transmit the driving force from the
pinion; a pair of driving pulleys engaging with the belt so as to
receive the driving force from the pinion; a pair of screw rod
combined with each of the driving pulley for rotating together with
each of the driving pulley; and a pair of housings having female
thread for engaging with each of the screw rod, whereby a pair of
screw rods are simultaneously extruded from or simultaneously
inserted into each of the housing by the same length.
[0017] This is intended to control a pair of extendable rods
including the screw rods and the housings to be extended or
contracted by the same amount based on that the driving force from
the driving unit is transmitted via the belt to a pair of the
driving pulleys so that a pair of the driving pulleys rotates by
the same amount.
[0018] Herein, at least one idler pulley engaging the belt is
additionally included thereby obtaining the higher wrapping angle
of the pinion surrounded by the belt. Therefore, the friction
between the pinion and the belt is increased, and the driving force
can be transmitted to a driving pulley without any loss.
[0019] Periodical grooves are formed on the outer sides of the
pinion, the idler pulley and the driving pulley, and also, the
periodical protuberances engaged with the grooves are formed so as
to thoroughly remove any slip between the belt and the pulleys due
to the increase of the friction, thereby precisely controlling the
screw rod's displacement.
[0020] It is effective to further comprising: a bracket for
rotatably fixing the pinion, the idler pully, and the driving
pulleys as one module; bracket hinges formed on both end sides the
bracket to be pivotally combined with the track part of a
treadmill; and housing hinges formed at each of the housings,
whereby the actuator can be easily combined with a treadmill which
realizes stable control of the inclination of the track part.
[0021] Meanwhile, the actuator for controlling the inclination of a
treadmill can use chain or gear instead of the belt as a power
transmission means in order to embody the same function.
[0022] That is, the treadmill can comprise a driving unit; a pinion
rotatably driven by the driving unit; at least one pair of
intermediate gear formed to transmit the driving force from the
pinion; a pair of driving gears engaging with the intermediate
gears so as to receive the driving force from the pinion; a pair of
screw rod combined with each of the driving gear for rotating
together with each of the driving gear; and a pair of housings
having female thread for engaging with each of the screw rod,
whereby a pair of screw rods are simultaneously extruded from or
simultaneously inserted into each of the housing by the same
length.
[0023] Herein, the intermediate gears can be plural at one side
between the pinion and the driving pulley because it is necessary
to install the driving pulleys apart from the pinion in the narrow
and long bracket.
[0024] On the other hand, the present invention provides with an
inclination control device for a treadmill having at least one
track part comprising: at least one extendable rod pivotally
connected with at least one second hinge which moves together with
the support member, and pivotally connected with a third hinge of
the track part which is located apart from the first hinge at the
track part; wherein, the inclination of the track part is
controlled by the extension or the contraction of the extendable
rod.
[0025] That is, the first hinge, the second hinge and the third
hinge form three-link structure, thereby securely support the track
part. Although the actuator is located in the front area of the
track belt on which user put their feet, as the load and/or impact
from a user is not concentrated on the screw rod of the actuator
because three elements (i.e., the track part, the support member,
and the screw rod with the housing) make up a three-link mechanism,
the screw rod can be designed to be smaller diameter or to be a
smaller size for obtaining the required durability, thereby
realizing the small-sized actuator and saving the manufacturing
cost.
[0026] It is desirable to include a traverse member to connect
between a pair of the support members for obtaining stability.
[0027] Also, the second hinge is located at the traverse member so
as to easily pivotally combine the extendable rod (more
specifically, housing) with the traverse member, thereby achieving
the lower manufacturing cost.
[0028] It is effective for each roller to be attached at the end of
the support members contacted with the ground, thereby reducing
friction between the support member and ground when the inclination
of the track part is controlled.
[0029] When the length of the support member is assumed as L, it is
desirable that the second hinge is located in 0.1 L or 0.5 L from
one end of the support member contacted with ground. It means that
the second hinge is formed near to ground so as to reduce the load
applied on the screw rod.
[0030] The gear can be used as a means of transmitting power from
the drive unit for controlling the inclination of the
treadmill.
BRIEF DESCRIPTION OF THE DRAWINGS
[0031] These and/or other objects and advantages of the invention
will become apparent and more readily appreciated from the
following description of preferred embodiments, taken in
conjunction with the accompanying drawings of which:
[0032] FIGS. 1 and 2 are views illustrating an inclination control
device of a conventional treadmill, in which:
[0033] FIG. 1 is a side view illustrating a structure of
inclination control device of treadmill;
[0034] FIG. 2 is a side view showing the reaction force on the
inclination control device of FIG. 1 as a user exercises
thereon;
[0035] FIGS. 3 to 7 are views illustrating an actuator for
controlling an inclination of the track part of the treadmill in
accordance with one embodiment of the present invention;
[0036] FIG. 3 is perspective views of part of the actuator when the
extendable rod thereof is contracted.
[0037] FIG. 4 is perspective views of part of the actuator when the
extendable rod thereof is extended.
[0038] FIG. 5 is a perspective view of the actuator adding a hinge
bracket into the part of the actuator of FIG. 3;
[0039] FIG. 6 is a perspective view of the actuator from another
view;
[0040] FIG. 7 is a plane view of FIG. 5;
[0041] FIG. 8 is a schematic view illustrating a structure of an
actuator for controlling an inclination of the track part of the
treadmill in accordance with another embodiment of the present
invention;
[0042] FIGS. 9 to 12 are views illustrating an inclination control
device using the actuator shown in FIG. 5 for a treadmill in
accordance with one embodiment of the present invention;
[0043] FIG. 9 is a perspective view illustrating the treadmill when
the inclination of the track part is high position;
[0044] FIG. 10 is a perspective view illustrating a structure of
the treadmill when the inclination of the track part is low
position;
[0045] FIG. 11 is a perspective view illustrating a structure of
treadmill without a driving cover when the inclination of the track
part is low position;
[0046] FIG. 12 is a side view of the treadmill shown in FIG. 10;
and
[0047] FIG. 13 is a FIG. to explain the three-linked truss
structure for diverging the load from walking or running of a
user.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
[0048] Hereinafter, an actuator for controlling an inclination of a
treadmill according to a preferred embodiment of the present
invention will be described.
[0049] As illustrated in FIGS. 3 to 7, the actuator 130 for
controlling the inclination of a treadmill in accordance with one
embodiment of the present invention comprises a driving unit for
generating and transmitting the driving torque; and a pair of
extendable rod 140 which can be extended or contracted in its
length by using the power transmitted from the driving unit.
[0050] The driving unit has an actuator motor 131 generating
rotating force; a transmission 132 for reducing the rotating speed
of a actuator motor 131; a pinion 133 rotatably combined with the
transmission 132; a belt 137 to transmit rotating power via the
pinion 133; driving pulleys 135, 136 rotatably installed by the
power transmitted from the pinion via the belt 137, an idler pulley
134 rotatably installed for changing the path of the belt 137
between the pinion 133 and driving pullys 135, 136 so as to
increase the wrapping angle of the pinion 133; the belt 137
transmitting the driving force from the pinion 133 to the driving
pulley 135, 136; a bracket 138 rotatably fixing the pinion 133,
idler pulley 134, and driving pulleys 135, 136 for forming them as
one module; a pair of protuberances 138a at both end sides of the
bracket 138 to be pivotally combined with the track part 110 of the
treadmill 100; and a fixing plate 139 on a low side of the bracket
138 for fixing the transmission 132.
[0051] In order to prevent the slip between the belt 137 and
pulleys (including pinion 133, idler pulley 134 and a pair of
driving pulleys 135, 136), although not shown in the Figures, it is
effective that grooves are periodically formed at outside of the
pulleys 133, 134, 135, 136, and that protuberances for engaging
with the grooves respectively are periodically formed at one side
or at both sides of the belt 137. A commercially used V-groove type
belt having protuberances on its one side can be applied thereto
through twisting the belt by 180 between the pinion 133 and the
idler pulley 134 and between the idler pulley 134 and the driving
pulley 135.
[0052] Also, as shown in FIGS. 3 to 5 and 7, by the installation of
the idler pulley 134 in the bracket 138 for changing the path of
the belt 137, the wrapping angle of the pinion 133 is increased
more than 180.degree. so that precise control of the rotation angle
of the driving pulleys 135, 136 can be realized by the increase of
the driving friction therebetween.
[0053] A pair of the extendable rod 140 rotates together with each
of the driving pulleys 135, 136 fixed to the upper end thereof.
Each extendable rod 140 includes a screw rod 142 having thread on
its whole length, and a housing 141 having female thread for
engaging with the thread of the screw rod 142, and thus, each
extendable rod 140 can become longer when the screw rod 142 is
extruded from the housing 141 by relative rotation therebetween,
and become shorter when the screw rod is inserted into the housing
141.
[0054] Herein, a hinge hole 141a as a housing hinge is formed at
the low end of the respective housing 141 for being pivotally
combined with each of second hinges 141a of the track part 110. In
order for the driving pulleys 135, 136 and the bracket 138
integrally move together, the bracket 138 is fastened by nuts 142b.
That is, groove is formed between the nut 142b and the driving
pulleys 135, 136 in the direction of circumference and the bracket
138 is inserted within the groove 142a.
[0055] The drawing notation of 132a is a bearing installation part
supporting rotation of a rotating axis 132b to connect the
transmission 132 and a pinion 133, and the drawing notation of 139a
is a bolt to fix the fixing plate 139 to the bracket 138.
[0056] Hereinafter, operation principle of the actuator 130 in
accordance with one embodiment of the present invention is
explained.
[0057] When the actuator motor 131 rotates in order to drive the
contracted extendable rod 140 to be extended as illustrated in FIG.
5, the driving torque is transmitted from the actuator motor 131 to
the pinion 133, and the pinion 133 is driven to rotate
counterclockwise. Accordingly, an idler pulley 134 connected by the
belt 137 with the pinion 133 is driven to rotate clockwise, and
simultaneously, a pair of driving pulleys 135, 136 is driven to
rotate counterclockwise. As one end 141a of the housing 141 is
fixed to other component such as a support member 151 or a traverse
member 153, the housing 141 is restricted not to rotate any longer.
Thus, as the driving pulley 135, 136 are driven rotate
counterclockwise, a pair of the screw rods 142 accordingly rotate
together with the pulleys 135, 136 at the same angle, and thus, a
pair of screw rods 142 is to be upwardly (142c) extruded from the
housing 141 by the same length each other, whereby the length d of
the extendable rod become longer as shown in FIG. 5.
[0058] Similarly, when the actuator motor 131 rotates in order to
drive the extended extendable rod 140 to be contracted as
illustrated in FIG. 3, the driving torque is transmitted from the
actuator motor 131 to the pinion 133, and the pinion 133 is driven
to rotate clockwise. Accordingly, an idler pulley 134 connected by
the belt 137 with the pinion 133 is driven to rotate
counterclockwise, and simultaneously, a pair of driving pulleys
135, 136 is driven to rotate clockwise. As one end 141a of the
housing 141 is fixed to other component such as a support member
151 or a traverse member 153, the housing 141 is restricted not to
rotate any longer. Thus, as the driving pulley 135, 136 are driven
rotate clockwise, a pair of the screw rods 142 accordingly rotate
together with the pulleys 135, 136 at the same angle, and thus, a
pair of screw rods 142 is to be downwardly (142d) extruded from the
housing 141 by the same length each other, whereby the length d of
the extendable rod become shorter as shown in FIG. 3
[0059] In the above manner, the actuator 130 can precisely control
the length of a pair of the extendable rod simultaneously.
[0060] It is also possible that the actuator for controlling the
inclination of the treadmill of the present invention can drive as
a manner of transmitting power from a motor to a screw rod of the
extendable rod using plural gears as shown FIG. 8.
[0061] Hereinafter, details of another embodiment of the present
invention including plural gears will be explained.
[0062] As illustrated in FIG. 8, an actuator 230 for controlling
the inclination by using gears for transmitting the driving torque
comprises a driving unit generating the driving torque, and a pair
of extendable rods 140 of which length are contracted and extended
by the driving torque transmitted from the driving unit. Herein, in
order to clarify this embodiment, an explanation of the detailed
structure described above on the extendable rod 140 is omitted as
it is identical or similar to the foregoing embodiment.
[0063] The driving unit includes The driving unit has an actuator
motor 131 generating rotating force; a pinion gear 233 rotatably
driven by the actuator motor 131; intermediate gears 234, 234',
234'' engaging the pinion gear 233; a pair of driving gears 235,
236 fixed to rotate together with a screw rod 142 engaging the
intermediate gears 234-234'' and a bracket 138 formed for rotatably
fix the gears 233, 234, 234', 234'', 235, 236 as one module.
[0064] In case that the pinion gear 233 is located in the center of
bracket 138, it is possible to arrange intermediate gear 126
symmetrically. However, in the case that the pinion gear 233 is not
located in the center of bracket 138, such is not possible. For
example, as shown in FIG. 8, when the pinion gear 233 is placed
left from the center, one intermediate gear 234 is installed
between the pinion gear 233 and left driving gear 135, while three
gears 234, 234', 234'' are installed between the pinion gear 233
and right driving gear 136. That is, it is not needed to set up the
same number of left and right gear and it is enough to balance the
number of the teeth of gears to be engaged each other. When the
number of left and right gears is different, a moving direction of
left and right screw rods 142 can be matched by means of balancing
the number of intermediate gear. That is, when the number of one
side of intermediate gear 234 is odd, that of the other side of
intermediate gears 234-234'' should be odd, and when the number of
one side of intermediate gear 234 is even, that of the other side
of intermediate gears 234-234'' should be even.
[0065] Hereinafter, operation principle of the actuator 230 in
accordance with another embodiment of the present invention is
explained.
[0066] In order to control the length of the extendable rod 140, as
a actuator motor 131 is driven to rotate, a pinion gear 233 also
rotates interlocked with the actuator motor 131. Thus, one or
several intermediate gears 233, 233', 233'' engaged with the pinion
gear 233 also rotate in the opposite direction, and the driving
pulleys 235, 236 engaged with intermediate gears 234 is also driven
rotate. According to the rotation of the driving gears 235, 236, a
pair of the screw rod 142 fixed to the driving gears 235, 236
respectively move up and down by being extruded from or being
inserted into the housing 141 so that the length of extendable rod
140 can be contracted or extended.
[0067] Furthermore, the mechanism of power transmission in
accordance with one embodiment of the present invention is not
limited to the above described belt system as well as the gear
system. The scope of the present invention includes a power
transmission by driving the driving means such as driving pulleys
135, 136 with a chain system, and also includes the construction of
which extendable rod comprises a rack gear engaging driving gears
235, 236.
[0068] On the other hand, the present invention provides with an
inclination control device of treadmill using the above actuator
for controlling the inclination of a treadmill. Hereinafter,
details of an inclination control device of a treadmill in
accordance with one embodiment referring to FIGS. 9 to 13.
[0069] FIG. 9 is a perspective view illustrating the treadmill when
the inclination of the track part is high position, and FIG. 10 is
a perspective view illustrating the structure of treadmill without
the driving cover shown in FIG. 9. The treadmill 101 with the
inclination control device in accordance with one embodiment of the
present invention comprises a track part 110 on which user run or
walk; a track driving unit 120 for driving the track belt 112 to
rotate endlessly of the track part 110; an inclination control
device to control the inclination of the track part 110 by
including the actuator 130, the extendable rod 140 and a front
support 150 to uphold the track part 110 with controlling the
inclination thereof; a rear support 160 to uphold a rear part of
the track part 110; and a column part 170 vertically protruded from
the track part 110.
[0070] The track part 110 includes a main bracket 111 to cover the
bottom side of the track part 110; a footplate (not shown)
installed in the main bracket to uphold the load of user; a support
frame (not shown) installed in the main bracket to support the
footplate; a track belt 112 installed to cover the upper and lower
sides of the footplate for endlessly rotating; a side cover 113 to
cover both sides of upper part of the main bracket 111; a plate 114
fixed to the upper side of the front part of the main bracket 111
and having a hinge hole 114a to be pivotally combined with each of
the protuberance 138a of the bracket 138 of the actuator shown in
FIG. 4; a first hinge plate 115 located at the lower side of the
main bracket 111 to pivotally combined with the end of the support
member 151; a fixing plate 116 located at the upper side of the
main bracket 111 for easily combining the column part 170.
[0071] The track driving unit 120 includes a track driving motor
121 generating the rotating power driving the track belt 112 of the
track part 110, a connection belt 122 transmitting power of the
track driving motor 121, a driving roller 123 connected with the
connection belt for being driven to rotate by the track driving
motor 121, an idler roller 124 located at the rear part of the
track part 110, and a driver unit cover 125 for preventing the
undesirable dusts or particles from entering into the track driving
motor 121.
[0072] The front support 150 includes a pair of support members 151
pivotally connected to each of the first bracket 115 located at
both sides of the lower part of track part 110, a roller 152
rotatably combined with the end of each of the support member 151
so that the end of the support member 151 can smoothly slide
against the ground. And the support member 151 includes a traverse
member 153 to connect the both support members 151 each other.
Herein, a first hinge 151a is formed at the pivotally connected
point between the support member 151 and the first bracket 115 of
the track part 110.
[0073] The rear support 160 has contact portions made of rubber
material for preventing the unexpected slide between the rear
support 160 and the contact portion.
[0074] The column part 170 includes a column 171 upwardly
stretching from the track part 110 by combining with the fixing
plate 116, a handle attached to the other end of column 171, and a
control panel 173 combined with the end of the handle for inputting
the exercise program and displaying exercise information.
[0075] The inclination control device includes the actuator 130 for
simultaneously controlling the length of the extendable rod 140 by
the same amount, the expandable rod 140 as described above, and a
front support 150 for upholding the front part of track part
110.
[0076] The actuator 130 is structured as illustrated in FIG. 3 or
FIG. 7 and above mentioned. How to install the actuator 130 in a
treadmill is as follow.
[0077] As illustrated in FIG. 13, an inclination control device of
treadmill of the present invention can efficiently prevent its
members 110, 151, 141 from being concentrated by load from a user
due to three-link truss structure of which three hinges 151a, 141a,
138a are formed as rotatable.
[0078] Also, by supporting both sides of the track part 110 with
two extendable rods, an inclination of the track part 110 in the
width direction can be prevented thereby preventing the fluctuation
or unbalance thereof in the width direction.
[0079] Comprised as above mentioned, the operation mechanism of the
inclination control device of the treadmill can be easily
understandable referring to that of the foregoing actuator in FIG.
3 and FIG. 4. A difference of rotating direction of the actuator
motor 131 makes a pair of screw rods 141 be extruded from the
housing 141 by the same length so that the inclination of the track
part 110 can be precisely controlled. FIG. 12 illustrates the
situation when the length d of extendable rod 140 gets shortest,
and thus, the downward inclination of the track part 110 is
realized within the range between -10.degree. and 0.degree.
[0080] Referring to FIG. 12, in case that the load Fp due to a
user's exercise thereon is applied on the front part B of track
part 110 as indicated in FIG. 12, the reaction force Fa on the
extendable rod 140 and the reaction force Fs on the support member
151 can be calculated as following equations 2 and 3.
Fs=Fp.times.(L2/L1) EQUATION 2 Fa=Fp.times.(L4/L3) EQUATION 3
[0081] Therefore, different from the reaction force for the
inclination control device of a conventional treadmill (see
equation 1), the reaction force Fa on the extendable rod 140 in the
axial direction thereof is came to be reduced rather than be
increased. Furthermore, any moment is not applied on the extendable
rod, since both ends of the extendable rod 140 are formed as the
rotatable hinges 138a, 141a. In view that a member came to be
broken due to the repeated bending fatigue loads, the actuator 130
can have almost permanent life span because any moment is not
applied on the extendable rod 140. As the moment and the reaction
force Fa of the extendable rod 140 are minimized, it is possible to
design the extendable rod to have a minimized diameter, thereby
also realizing the smaller capacity of the actuator motor as well
as the reduced weight of the extendable rod 140 (i.e., the housing
141 and the screw rod 142) Accordingly, energy consumption required
to drive and to manufacture the actuator 130 can be also
reduced.
[0082] In addition, by letting the second hinge 141a far apart from
the track part 110, as the reaction force on the extendable rod 140
in the axial direction thereof can surprisingly be reduced, when
the length of the support member 151 is assumed to be L5, it is
more desirable that the length of L3 is longer than 0.5*L5.
[0083] As above explained, The present invention provides with an
actuator for inclination controlling of treadmill, which comprises:
a motor, a pinion rotating with power of the motor, a belt for
transmitting power from the motor, a pair of driving pulleys
rotatably engaged with the belt, a pair of the screw rod combined
with the driving pulley on its one end, a female screw engaging a
screw thread of the screw rod, a housing attached to the screw rod
by the female screw so that it facilitates inclination control of a
track of the treadmill.
[0084] In order to maintain the track part stable during a user's
exercise on the track part, a pair of the extendable rod including
the screw rod and the housing can be contracted or extended by the
same length so that the treadmill can be easily and precisely
controlled.
[0085] In addition, as the present invention provides with an
inclination control device of treadmill using the actuator
supporting both sides of track part with a pair of the extendable
rods, a user can run or walk on the track part 110 without an
inclination in the width direction which causes a user feel to
unstable and unsafe.
[0086] The present invention also can save manufacturing cost and
enhance durability surprisingly because the load can be effectively
diverged and the moment on the extendable rod is removed by
constructing one or a pair of three-linked truss structure of which
hinges are all rotatable relative to the near members. Also, the
actuator according to the present invention can save power
consumption for driving and manufacturing cost.
[0087] As the present invention may be embodied in several forms
without departing from the spirit or essential characteristics
thereof, it should also be understood that the above-described
embodiments are not limited by any of the details the foregoing
description, unless otherwise specified, but rather should be
construed broadly within its spirit and scope as defined in the
appended claims, and therefore all changes and modifications that
fall within the metes and bounds of the claims, or equivalence of
such metes and bounds are therefore intended to be embraced by the
appended claims.
[0088] On the other hand, although the actuator 130 using belt 137
for transmitting the driving toque is described above as one
embodiment of the present invention, any actuator capable of
simultaneously controlling a pair of the extendable rod 140 is
within the scope of the present invention. Also, the inclination
control device having a pair of the extendable rod 140 for
achieving three hinges 138a, 141a, 151 for three-linked truss
structure is described above as one embodiment of the present
invention, an inclination control device only having one extendable
rod 140 is also within the scope of the present invention.
* * * * *