Note: Descriptions are shown in the official language in which they were submitted.
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1 HEIGHT-ADJUSTABLE THREE-WHEELED CHAIR
2
3 BACKGROUND OF THE INVENTION
4 1. Field of the Invention
The present invention relates to a height-adjustable three-wheeled chair, and
more
6 particullarly, to a height-adjustable three-wheeled chair, which can allow a
user to move along a
7 furrow of a cultivated field while sitting on a seat provided thereon, to
adjust the level of the
8 seat according to the surface gradient of the cultivated field, thereby
improving user's
9 convenience and comfort.
2. Description of the Related Art
11 In general, since crops are grown on ridges of a cultivated field of
greenhouse or
12 opened area, the cultivated field is often not flat but grooved.
13 Especially, since a farmer should bend over when growing and harvesting
crops such as
14 grapes, tomatoes, red peppers, etc., the farmer frequently gets fatigued or
aches in his or her
back, resulting in deteriorating workability.
16 For example, in case of thinning out bunches of grapes which requires the
farmer to
17 work in a stooping posture for a long time, the farmer may suffer from
musculoskeletal diseases.
18 To solve these problems, Korean Utility Model Registration No. 112544
(registered on
19 April 9, 1998), entitled "Improved Chair for Farm Work" discloses a seat
board that is moved up
and down according to the height of a user or a growing crop to adjust the
unevenness such that
21 the user can easily do farm work using the chair, and the chair can be
readily transported
22 before or after the farm work.
23 Moreover, Korean Unexamined Patent Publication No. 1999-0040466 (published
on
24 June 05, 1999), entitled "Furrow Work Chair" discloses a technology which
allows a user sitting
on the chair to move the chair left and right while doing farm work, in which
wheels for moving left
26 and right are mounted at the bottom of the chair such that the worker
sitting on the chair can
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1 move left and right using his or her feet, and a height-adjusting means and
a rotatable
2 connecting means are included in the chair.
3 The above-described prior arts relate to work chairs that allow an old
person or woman
4 sitting thereon to move freely while managing the crops; however, these work
chairs do not have
the function of adjusting the level of the chair according to the surface
gradient of the cultivated
6 field.
7 Therefore, it is difficult for the user to maintain the level while working
on a slope, and
8 thus work-related fatigue is increased.
9 To solve these problems, a three-wheeled chair for farm work which includes
the
function of adjusting the level of the chair on a slope is disclosed in Korean
Patent Registration
11 No. 0849205 (July 23, 2008) filed by the present inventor.
12 The above information disclosed in this Background section is only for
enhancement of
13 understanding of the background of the invention and therefore it may
contain information that
14 does not form the prior art that is already known in this country to a
person of ordinary skill in the
art.
16
17 SUMMARY OF THE INVENTION
18 The present invention has been made in an effort to solve the above-
described problems
19 associated with prior art. Accordingly, the present invention provides a
height-adjustable
three-wheeled chair, which can allow a user sitting on a seat thereof to move
along a furrow of a
21 cultivated field, adjusting the level of the seat according to the surface
gradient of the cultivated
22 field, thereby improving user's convenience and comfort.
23 The present invention has a feature in that the functions of adjusting the
height and level
24 of a thee-wheeled chair for farm work, which are disclosed in Korean Patent
Application No.
2007-39112 (April 23, 2007), are improved such that a user can easily operate
the three-wheeled
26 chair.
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1 In one aspect, the present invention provides a height adjustable three-
wheeled chair,
2 which comprising: a main frame; a seat located above the main frame; a
height adjusting device
3 for moving up and down the seat, the height adjusting device being built in
the main frame; a
4 wheel axle formed on an upper front surface of the main frame; a running
wheel mounted on the
wheel axle; an auxiliary frame assembled at the rear of the main frame by
means of an insertion
6 rod and a height adjusting pipe, the insertion rod being vertically
installed to the vicinity of an
7 upper end of the main frame and the height adjusting pipe being vertically
installed on the
8 auxiliary frame; and a pair of lifting wheels mounted on the auxiliary
frame, wherein the insertion
9 rod is configured to move up and down within the height adjusting pipe and
is fixed at a desirous
position such that the height of the lifting wheels and the auxiliary frame
can be adjusted as
11 needed.
12 In a preferred embodiment, the auxiliary frame includes a U-shaped frame
and a
13 horizontal frame, which are integrally formed with each other, the lifting
wheels are rotatably
14 mounted on both ends of the U-shaped frame, and the height-adjusting pipe
is vertically installed
at a position corresponding to the insertion rod such that the insertion rod
is inserted into the
16 inside of the height-adjusting pipe.
17 In another preferred embodiment, the insertion rod is installed at each of
both sides of
18 the main frame and the height-adjusting pipe is installed at each of both
sides of the auxiliary
19 frame, respectively.
In still another preferred embodiment, the insertion rod includes a plurality
of insertion
21 holes spaced at a predetermined distance in the longitudinal direction, and
the height-adjusting
22 pipe includes a through-hole, such that the height-adjusting pipe is fixed
in the insertion rod by a
23 stopper pin inserted into a specific insertion hole of the insertion rod
through the through-hole of
24 the height-adjusting pipe.
In yet another preferred embodiment, a fixing pipe, in which a lower end of a
support
26 frame is inserted and fixed, is mounted on the auxiliary frame, a bucket
support is integrally
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1 mounted on an upper end of the support frame, and a bucket in which a
harvest or a working tool
2 is put is assembled on the bucket support.
3 In still yet another preferred embodiment, the lower end of the support
frame inserted
4 into the inside of the fixing pipe is fixed by a screw fixing device
penetrating the fixing pipe.
In a further preferred embodiment, a rotation stop bar is installed at the
wheel axle of the
6 main frame to stop the rotation of the running wheel, in which one end of
the rotation stop bar is
7 rotatably connected to the wheel axle by a hinge such that the rotation stop
bar is rotated
8 downward to be fitted onto the top of the outer circumference of the running
wheel, thus pressing
9 the running wheel and stopping the rotation of the running wheel.
In another further preferred embodiment, wherein the height-adjusting device
is a gas
11 cylinder or hydraulic cylinder type spindle device having a spindle, on
which the seat is integrally
12 mounted, and vertically mounted on the main frame, such that the spindle is
moved up and down
13 by the flow of working fluid in the cylinder according to the operation of
an operation lever, thus
14 adjusting the height of the seat.
16 BRIEF DESCRIPTION OF THE DRAWINGS
17 The above and other features of the present invention will be described in
reference to
18 certain exemplary embodiments thereof with reference to the attached
drawings in which:
19 FIG. 1 is a perspective view showing a height-adjustable three-wheeled
chair in
accordance with a preferred embodiment of the present invention;
21 FIG. 2 is a perspective view showing an operation state of a seat that
moves up and
22 down by a cylinder device in the height-adjustable three-wheeled chair in
accordance with the
23 preferred embodiment of the present invention;
24 FIG. 3 is a perspective view showing an operation state of a pair of
lifting wheels that is
lifted up and down in the height-adjustable three-wheeled chair of the present
invention;
26 FIG. 4 is a side view showing the operation state of the pair of lifting
wheels that is lifted
27 up and down in the height-adjustable three-wheeled chair of the present
invention;
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1 FIG. 5 is a perspective view showing a state where a support frame and a
bucket are
2 assembled in the height-adjustable three-wheeled chair of the present
invention; and
3 FIG. 6 is a perspective view showing a state where the rotation of a running
wheel is
4 stopped by a rotation stop bar in the height-adjustable three-wheeled chair
of the present
invention.
6 It should be understood that the appended drawings are not necessarily to
scale,
7 presenting a somewhat simplified representation of various preferred
features illustrative of the
8 basic principles of the invention. The specific design features of the
present invention as
9 disclosed herein, including, for example, specific dimensions, orientations,
locations, and shapes
will be determined in part by the particular intended application and use
environment. In the
11 figures, reference numbers refer to the same or equivalent parts of the
present invention
12 throughout the several figures of the drawing.
13
14 DETAILED DESCRIPTION OF THE INVENTION
Hereinafter reference will now be made in detail to various embodiments of the
present
16 invention, examples of which are illustrated in the accompanying drawings
and described below.
17 While the invention will be described in conjunction with exemplary
embodiments, it will be
18 understood that present description is not intended to limit the invention
to those exemplary
19 embodiments. On the contrary, the invention is intended to cover not only
the exemplary
embodiments, but also various alternatives, modifications, equivalents and
other embodiments,
21 which may be included within the spirit and scope of the invention as
defined by the appended
22 claims.
23 FIG. 1 is a perspective view showing a height-adjustable three-wheeled
chair in
24 accordance with a preferred embodiment of the present invention, and FIG. 2
is a perspective
view showing an operation state of a seat that goes up and down by a cylinder
device in the
26 height-adjustable three-wheeled chair in accordance with the preferred
embodiment of the
27 present invention.
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1 FIG. 3 is a perspective view showing an operation state of a pair of lifting
wheels that is
2 lifted up and down in the height-adjustable three-wheeled chair of the
present invention, and FIG.
3 4 is a side view showing the operation state of the pair of lifting wheels
that is lifted up and down
4 in the height-adjustable three-wheeled chair of the present invention.
FIG. 5 is a perspective view showing a state where a support frame and a
bucket are
6 assembled in the height-adjustable three-wheeled chair of the present
invention, and FIG. 6 is a
7 perspective view showing a state where the rotation of a running wheel is
stopped by a rotation
8 stop bar in the height-adjustable three-wheeled chair of the present
invention.
9 As shown in FIG. 1, in a height-adjustable three-wheeled chair 100 of the
present
invention (hereinafter referred to as a chair), a height-adjusting device 111
for moving up and
11 down a seat 101 to adjust the height thereof is mounted on a main frame 110
located at the
12 center of the chair 100, the height-adjusting device 111 being built in the
main frame 110 in the
13 vertical direction.
14 The height-adjusting device 111 may be implemented by a gas (or pneumatic)
cylinder
type spindle device or a hydraulic cylinder type spindle device, which are
widely used as
16 height-adjusting devices of household chairs.
17 For example, a gas cylinder type spindle device includes a spindle 112 that
moves up
18 and down, and the seat 101 is integrally mounted on the upper end of the
spindle 112.
19 Moreover, the spindle device includes an operation lever 113 projecting
from the bottom
of the seat 101 to the side such that the spindle 101 integrally formed with
the seat 101 is moved
21 up or down by the flow of working fluid (gas) in the cylinder in connection
with the operation of
22 the operation lever 113.
23 That is, when a user operates the operation lever 113 to adjust the height
of the seat 101,
24 the spindle 112 is moved up or down by the flow of working fluid (gas) in
the cylinder, and thus
the seat 101 is moved up or down to reach a desired height.
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1 Therefore, the user can adjust the height of the seat 101 according to the
height of a
2 growing crop by operating the operation lever 113, and thus the user sitting
on the seat 101 can
3 do the farm work more easily and conveniently.
4 A wheel axle 114 is integrally formed on an upper front surface of the main
frame 110 in
the vertical direction, and a running wheel 115 is rotatably mounted on a
lower end of the wheel
6 axle 114.
7 Moreover, an insertion rod 116 is vertically installed at both sides of the
upper end of the
8 main frame 110, respectively.
9 Each of the insertion rods 116 includes a plurality of insertion holes 116a
spaced at a
predetermined distance in the longitudinal direction, and a stopper pin 124
for fixing the height of
11 an auxiliary frame 120 and a pair of lifting wheels 125, which will be
described later, is inserted
12 into the insertion hole 116a.
13 Meanwhile, the chair 100 of the present invention includes the pair of
lifting wheels 125
14 capable of being lifted up and down with respect to the main frame 110 and
the running wheel
115 mounted thereon. The lifting wheels 125 are rotatably mounted on both ends
of the
16 auxiliary frame 120 assembled at the rear of the main frame 110.
17 The auxiliary frame 120 includes a U-shaped frame 121 and a horizontal
frame 122,
18 which are integrally welded to each other. Both ends extending vertically
from the U-shaped
19 frame 121 of the auxiliary frame 120 serve as wheel axles, on which the
lifting wheels 125 are
rotatably mounted.
21 In the chair 100 of the present invention, the running wheel 115 and the
lifting wheels
22 125 are mounted such that the chair 100 can move in the left and right
directions with respect to
23 the user sitting on the seat 101. When the user sitting on the seat 101
pushes the ground with
24 his or her legs, the running wheel 115 and the lifting wheels 125 roll on
the ground such that the
user sitting on the seat 101 can move left and right.
26 Moreover, a height-adjusting pipe 123 is welded to each of both sides of
the auxiliary
27 frame 120, and each of the height-adjusting pipes 123 is vertically
installed at a position
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1 corresponding to the insertion rod 116 such that the insertion rod 116 of
the main frame 110 is
2 inserted into the inside of the height-adjusting pipe 123.
3 Each of the height-adjusting pipes 123 of the auxiliary frame 120 is
inserted downward
4 into the outside of the insertion rod 116 of the main frame 110 such that
the auxiliary frame 120 is
assembled with the main frame 110.
6 Moreover, a through-hole 123a, through which the stopper pin 124 is
inserted, is formed
7 at a specific position of the height-adjusting pipe 123.
8 As a result, after inserting the insertion rod 116 of the main frame into
the inside of the
9 height-adjusting pipe 123 of the auxiliary frame 120, the through-hole 123a
of the
height-adjusting pipe 123 and a specific one of the plurality of the insertion
holes 11 6a of the
11 insertion rod 116 are adjusted to coincide with each other, and then the
stopper pin 124 is
12 inserted into the corresponding insertion hole 116a of the insertion rod
116 through the
13 through-hole 123a of the height-adjusting pipe 123 (refer to FIG. 6).
14 When the stopper pin 124 is assembled in the above manner, the height of
the auxiliary
frame 120 and the lifting wheels 125 is fixed.
16 FIGS. 3 and 4 show the state where the height of the auxiliary frame 120
and the lifting
17 wheels 125 is adjusted to maintain the chair 100 in a horizontal position.
Basically, when the
18 stopper pin 124 is removed from the corresponding insertion hole 116a, the
height-adjusting pipe
19 123 can move up and down in the insertion rod 116, and thus the auxiliary
frame 120 and the
lifting wheels 125 move up and down with respect to the main frame 110, the
running wheel 115,
21 and the seat 101.
22 For example, as shown in the left side of FIG. 4, when the chair 100 needs
to move left
23 and right along a furrow on a cultivated field under the condition that the
lifting wheels 125 are
24 placed on a furrow surface 2, which is cut lower than a ground 1 on which
the running wheel 115
is placed, the height of the lifting wheels 125 should be adjusted to be lower
than that of the
26 running wheel 115 depending on the depth of the furrow surface 2.
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1 Accordingly, as shown in the right side of FIG. 4, when the user removes the
stopper pin
2 124, the height-adjusting pipe 123 moves down along the insertion rod 116
and the entire
3 auxiliary frame 120 moves down such that the lifting wheels 125 are in
contact with the furrow
4 surface 2. In this state, when the stopper pin 124 is inserted into an
appropriate insertion hole
116a to fix the height of the auxiliary frame 120 and the lifting wheels 125,
the chair 100 can
6 stably move while maintaining the level.
7 As such, when the stopper pin 124 is inserted and fixed in the insertion
hole 116a of the
8 insertion rod 116 through the through-hole 123a of the height-adjusting pipe
123 under the
9 condition that the lifting wheels 125 are in contact with the furrow surface
2, the height of the
entire auxiliary frame 120 including the lifting wheels 125 is adjusted with
respect to the chair 100
11 including the main frame 110, the running wheel 115, and the seat 101.
12 When it is necessary to raise the height of the lifting wheels 125, the
stopper pin 124 is
13 removed, the height-adjusting pipe 123 is raised up from the insertion rod
116, and then the
14 stopper pin 124 is inserted and fixed in an insertion hole 116a at a
position higher than the
previous one.
16 At this time, the auxiliary frame 120 and the lifting wheels 125 are raised
up and coincide
17 with the main frame 110 and the running wheel 115.
18 The height of the auxiliary frame 120 and the lifting wheels 125 can be
adjusted in
19 various ways, and thus the lifting wheels 125 may be positioned higher than
the lifting wheels
125.
21 Meanwhile, as shown in FIG. 5, a fixing pipe 126, in which a lower end of a
support
22 frame 131 is inserted and fixed, is welded to the side of each of the wheel
axles corresponding to
23 both ends of the auxiliary frame 120, more explicitly both ends of the U-
shaped frame 121. If
24 necessary, a fixing pipe (not shown) may be welded to a lower end side of
the wheel axle 114 of
the main frame 110.
26 In this case, a screw fixing device 127 is provided such that the lower end
of the support
27 frame 131 inserted into the inside of the fixing pipe 126 is fixed thereto.
The screw fixing device
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1 127 includes a handle 127a and a screw 127b and, at this time, the screw
127b penetrates the
2 fixing pipe 126 and fixes the lower end of the support frame 131 inserted
into the inside of the
3 fixing pipe 126.
4 In detail, when the lower end of the support frame 131 is inserted into the
inside of the
fixing pipe 126 and the handle 127a of the screw fixing device 127 is rotated,
the screw 127b
6 holds the lower end of the support frame 131 such that the support frame 131
is integrally fixed.
7 A bucket support 132 is integrally mounted on an upper end of the support
frame 131,
8 and a bucket 133 in which a harvest or a working tool can be put is
assembled on the bucket
9 support 132.
Here, it will be understood that the bucket 133 includes a basket, a box,
etc., which is
11 placed on the bucket support 132 of the support frame 131 and contains a
harvest or a working
12 tool.
13 FIG. 6 shows a stopping means for stopping the rotation of the running
wheel 115. As
14 the stopping means, a rotation stop bar 141, which is fitted onto the outer
circumference of the
running wheel 115, is mounted on the wheel axle 114 of the main frame 110.
16 As shown in FIGS. 1 to 6, the rotation stop bar 141 is fabricated by
bending a thin bar in a
17 U-shape and reconstructing the entire shape to match the shape of the outer
circumference of
18 the running wheel 115. One end of the rotation stop bar 141 is rotatably
connected to the
19 wheel axle 114 of the main frame 110 by a hinge.
When the running wheel 115 needs to be stopped, the user pulls down the
rotation stop
21 bar 141, holding the other end of the rotation stop bar 141, and fits the
rotation stop bar 141
22 onto the top of the outer circumference of the running wheel 115 such that
the rotation stop bar
23 141 presses the running wheel 115, thus stopping the rotation of the
running wheel 115.
24 Otherwise, when the running wheel 115 needs to be rotated, the user pulls
up the
rotation stop bar 141 such that it is connected to the wheel axle 114 of the
main frame 110.
26 Therefore, the running wheel 115 is free from the influence of the rotation
stop bar 141, and
27 thus it can freely roll on the ground.
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1 As described above, the height-adjustable three-wheeled chair according to
the present
2 invention provides the following advantages.
3 It is possible to adjust the height of the seat of the chair according to
the height of a user
4 and maintain the level of the seat by adjusting the height of the lifting
wheels according to the
surface gradient of the cultivated field, thus allowing the user to do farm
work easily and
6 conveniently. Moreover, it is possible to prevent the upper body of the user
sitting on the seat
7 of the chair from being tilted, thus effectively preventing musculoskeletal
diseases.
8 Especially, the height-adjustable three-wheeled chair is invented in
consideration of the
9 rural manpower consisting of aged persons, and the objects of the present
invention are to
allow the user to freely move on an inclined furrow, maintaining the level of
the seat on an
11 inclined surface and adjusting the height of the seat according to the
height of a growing crop,
12 thus allowing the user to do farm work easily and conveniently.
13 Moreover, since height-adjustable three-wheeled chair is equipped with a
bucket such as
14 a basket, a box, etc., in which a harvest or a working tool can be put, it
is possible to improve
work convenience.
16 The invention has been described in detail with reference to preferred
embodiments
17 thereof. However, it will be appreciated by those skilled in the art that
changes may be made in
18 these embodiments without departing from the principles and spirit of the
invention, the scope of
19 which is defined in the appended claims and their equivalents.
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