U.S. patent application number 15/624738 was filed with the patent office on 2018-12-20 for cart.
The applicant listed for this patent is Unique Product & Design Co., LTD.. Invention is credited to Chih-Ching Cheng.
Application Number | 20180362065 15/624738 |
Document ID | / |
Family ID | 64657035 |
Filed Date | 2018-12-20 |
United States Patent
Application |
20180362065 |
Kind Code |
A1 |
Cheng; Chih-Ching |
December 20, 2018 |
Cart
Abstract
A cart, at least a folding joint mechanism disposed among an
upper frame, a bottom frame and a rear wheel frame, comprising a
bottom frame joint having a first arc-rack, an upper frame joint
having a second arc-rack, a rear wheel frame joint, and a linkage
gear unit disposed between the upper and bottom frame joints, the
linkage gear unit having a first and a second gears rotating
coaxially and engaging with the first and second arc-rack
respectively, and the first and second gears having the numbers N1
and N2 of gear teeth respectively, and wherein N1 and N2 are
greater than or equal to 6.
Inventors: |
Cheng; Chih-Ching; (Tainan
City, TW) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Unique Product & Design Co., LTD. |
Tainan City |
|
TW |
|
|
Family ID: |
64657035 |
Appl. No.: |
15/624738 |
Filed: |
June 16, 2017 |
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
B62B 2205/18 20130101;
B62B 3/02 20130101; B62B 2202/404 20130101; F16H 19/001 20130101;
B62B 7/062 20130101; B62B 7/064 20130101 |
International
Class: |
B62B 7/06 20060101
B62B007/06; B62B 3/02 20060101 B62B003/02; F16H 19/00 20060101
F16H019/00; F16B 12/40 20060101 F16B012/40 |
Claims
1-10. (canceled)
11. A cart, comprising: an upper frame extending outwards toward a
first direction; a lower frame extending outwards toward a second
direction; a rear wheel frame extending outwards toward a third
direction; at least one folding joint mechanism disposed among the
upper frame, the bottom frame and the rear wheel frame, and
comprising: a bottom frame joint connected to an end of the bottom
frame, and the bottom frame joint including a first opening, and a
first arc-rack formed on a portion of an edge of the first opening;
an upper frame joint connected to an end of the upper frame, and
the upper frame joint including a second opening, and a second
arc-rack formed on a portion of an edge of the second opening; a
rear wheel frame joint connected to an end of the rear wheel frame;
and a linkage gear unit disposed between the bottom frame joint and
the upper frame joint, and the linkage gear unit having a first
gear and a second gear, and the first gear and the second gear
rotating coaxially, and wherein the first gear being engaged with
the first arc-rack and the second gear being engaged with the
second arc-rack, and the first gear having a number N1 of gear
teeth and the second gear having a number N2 of gear teeth, and the
first arc-rack having a first axle center, a first tooth and a
second tooth, and the second tooth being adjacent to the first
tooth, and the first tooth having a first end point connected to
the first axle center to form a first virtual line and the second
tooth having a second end point connected to the first axle center
form a second virtual line, and the second virtual line and the
first virtual line defining a first included angle .theta.1, and
the second arc-rack having a second axle center, a third tooth, and
a fourth tooth, and the fourth tooth being adjacent to the third
tooth, the third tooth having a third end point being adjacent to
the second axle center to form a third virtual line and the fourth
tooth having a fourth end point being adjacent to the second axle
center to form a fourth virtual line, and the third virtual line
and the fourth virtual line defining a second included angle
.theta.2, and the first and second arc-racks having the numbers N3
and N4 of gear teeth, and the upper frame extending outwards toward
a first direction, the bottom frame extending outwards toward a
second direction and the rear wheel frame extending outwards toward
a third direction, and the second direction and the third direction
defining a third included angle .theta.3 and the third direction
and the first direction defining a fourth included angle .theta.4,
and wherein N1, N2, .theta.1, and .theta.2 meeting the following
relations: 360/.theta.1=N3, .theta.1>0; 360/.theta.2=N4,
.theta.2>0; (N2/N4)*(N3/N1)=.theta.4/.theta.3, and both .theta.3
and .theta.4 fall within a range of 30.degree..about.150.degree.;
and at least one of N3 and N4 is not a positive integer, and both
N1 and N2 are positive integers, and both .theta.3 and .theta.4
fall within a range of 30.degree..about.150.degree..
12. The cart of claim 11, wherein the cart is particularly a baby
stroller or a golf trolley having three or more wheels.
13. The cart of claim 11, wherein both of the numbers N1 and N2 of
gear teeth of the first and second gears are greater than or equal
to 6.
14. The cart of claim 11, wherein the first direction, the second
direction and the third direction are different directions.
15. The cart of claim 11, wherein the sum of the third included
angle and the fourth included angle falls within a range of
120.degree..about.240.degree..
16. The cart of claim 11, wherein the first gear and the second
gear are independently separate parts.
17. The cart of claim 11, wherein the first gear and the second
gear are fixedly attached together.
18. The cart of claim 11, wherein the linkage gear unit further
comprises a base disposed between the first gear and the second
gear, and the diameter of the base is greater than the diameter of
the first gear.
19. The cart of claim 18, wherein the base includes a notch.
Description
BACKGROUND OF THE INVENTION
Field of the Invention
[0001] The present disclosure relates to a cart, in particular a
baby stroller and a golf trolley having three or more wheels, and
more particularly, to a folding joint mechanism on the left and
right sides of the cart.
Description of the Related Art
[0002] A cart, in the present disclosure, generally including the
baby stroller and the golf trolley having three or more wheels, and
the present disclosure, more particularly relates to the baby
stroller. The following description of the disclosure is further
explained by way of a four-wheel baby stroller.
[0003] In the prior art, a large number of baby strollers having
the gears with few gear teeth, but the following drawbacks should
be alleviated even though the construction is simple thereof.
[0004] 1. When the baby stroller is in an unfolded or folded state,
at the status of the angle of rotation is specific, the contact
ratio is definitely lower at the time of a gear engaged with the
internal gear teeth of a rotatable member due to the few gear teeth
of the gear, and the contact ratio is lower and the bearing stress
of the unit tooth is heavier accordingly. Therefore, when an
external force (including the folding or unfolding rotation force)
is exerted on the folding joint, the gear will be damaged more
easily and result in the shortage of the service life thereof.
[0005] 2. Furthermore, the gear located in the cart generally is a
complete gear, which an included angle defined in the peak of the
two adjacent gear teeth can be divisible by 360.degree.. In effect,
there is more design freedom and flexibility restricted since in
this design, the angle of the included angle of the bottom frame
and the rear wheel frame is limited, and fails to provide a free
adjustable function.
SUMMARY OF THE INVENTION
[0006] The primary object of the present disclosure is to provide a
cart capable of enhancing the strength of the gear so as to extend
the service life thereof.
[0007] Another object of the present disclosure is to provide a
cart capable of adjusting the angle of the included angle of the
frame freely so as to improve the freedom and flexibility of the
product design.
[0008] To achieve the aforementioned object, in the disclosure a
cart comprises an upper frame, a bottom frame, a rear wheel frame
and at least a folding joint mechanism, and the folding joint
mechanism is disposed among the upper frame, the bottom frame and
the rear wheel frame, comprising a bottom frame joint connected to
an end of the bottom frame, the bottom frame joint including a
first opening and a first arc-rack formed on a portion of the edge
of the first opening, an upper frame joint connected to an end of
the upper frame, the upper frame including a second opening and a
second arc-rack formed on a portion of the edge of the second
opening, a rear wheel frame connected to an end of the rear wheel
frame, and a linkage gear unit disposed between the bottom frame
joint and the upper frame joint, the linkage gear unit having a
first gear and a second gear rotating coaxially, and the first gear
being engaged with the first arc-rack, the second gear being
engaged with the second arc-rack, and wherein the first gear having
a number N1 of gear teeth and the second gear having a number N2 of
gear teeth, and the N1 and N2 are both greater than or equal to
6.
[0009] The aforementioned cart, in particular a baby stroller or a
golf trolley having three or more wheels.
[0010] The aforementioned first arc-rack has a first axle center, a
first tooth and a second tooth, and the second tooth is adjacent to
the first tooth, the first tooth has a first end point connected
with the first axle center to form a first virtual line, the second
tooth has a second end point connected with the first axle center
to form a second virtual line, and the second and first virtual
lines define a first included angle.theta.1. The second arc-rack
has a second axle center, a third tooth and a fourth tooth, and the
fourth tooth is adjacent to the third tooth, and wherein the third
tooth has a third end point connected with the second axle center
to form a third virtual line, the fourth tooth has a fourth end
point connected with the second axle center to form a fourth
virtual line, and the third and fourth virtual lines define a
second included angle .theta.2. The upper frame extends outwards
toward a first direction, the bottom frame extends outwards toward
a second direction and the rear wheel frame extends outwards toward
a third direction, and the second and third directions define a
third included angle .theta.3, the third and the first directions
define a fourth included angle .theta.4, and
[0011] further N1, N2, .theta.1, .theta.2 meet the following
relations:
360/.theta.1=N3, .theta.1>0;
360/.theta.2=N4, .theta.2>0; and
(N2/N4)*(N3/N1)=.theta.4/.theta.3, and both.theta.3 and.theta.4
fall within a range of 30.degree..about.150.degree..
[0012] At least one of the aforementioned numbers N3 and N4 of gear
teeth of the first and second arc-racks is not a positive
integer.
[0013] Both of the aforementioned numbers N1 and N2 of gear teeth
of the first and second gears are positive integers.
[0014] The sum of the aforementioned third included angle.theta.3
and the fourth included angle.theta.4 falls within a range of
120.degree..about.240.degree..
[0015] The aforementioned first and second gears are separate
parts.
[0016] The aforementioned first and second gears are fixedly
attached.
[0017] The aforementioned linkage gear unit further comprises a
base disposed between the first and the second gears, and the
diameter of the base is greater than the diameter of the first
gear.
[0018] In a preferred embodiment, the cart comprises an upper frame
extending outwards toward a first direction, a bottom frame
extending outwards toward a second direction and a rear wheel frame
extending outwards toward a third direction, and at least a folding
joint mechanism disposed among the upper frame, the bottom frame
and the rear wheel frame. The folding joint mechanism comprises a
bottom frame joint connected to an end of the bottom frame, the
bottom frame joint including a first opening and a first arc-rack
formed on a portion of the edge of the first opening, an upper
frame joint connected to an end of the upper frame, the upper frame
joint including a second opening and a second arc-rack formed on a
portion of an edge of the second opening, and a rear wheel frame
joint connected to an end of the rear wheel frame, and a linkage
gear unit disposed between the bottom frame join and the upper
frame joint, the linkage gear unit having a first gear and a second
gear rotating coaxially, and the first gear engaging with the first
arc-rack and the second gear engaging with the second arc-rack, and
the first gear having a number N1 of gear teeth, the second gear
having a number N2 of gear teeth, and the first arc-rack having a
first axle center, a first tooth and a second tooth, and the second
tooth being adjacent to the first tooth, and wherein the first
tooth having a first end point connected with the first axle center
to form a first virtual line, the second tooth having a second end
point connected with the first axle center to form a second virtual
line, and the second and first virtual lines defining a first
included angle.theta.1. The second arc-rack has a second axle
center, a third tooth and a fourth tooth, and the fourth tooth
being adjacent to the third tooth, and wherein the third tooth
having a third end point connected with the second axle center to
form a third virtual line, the fourth tooth having a fourth end
point connected with the second axle center to form a fourth
virtual line, and the third and the fourth virtual lines defining a
second included angle .theta.2. The first and second arc-racks have
the numbers N3 and N4 of gear teeth, the second and the third
directions define a third included angle .theta.3, and the third
and the first directions define a fourth included angle .theta.4,
and wherein N1, N2, .theta.1 and .theta.2 meet the following
relations:
360/.theta.1=N3, .theta.1>0;
360/.theta.2=N4, .theta.2>0;
(N2/N4)*(N3/N1)=.theta.4/.theta.3, and both.theta.3 and.theta.4
fall within a range of 30.degree..about.150.degree., and at least
one of N3 and N4 is not a positive integer, both N1 and N2 are
positive integers, and both.theta.3 and.theta.4 fall within a range
of 30.degree..about.150.degree..
[0019] The aforementioned cart in particular a baby stroller or a
golf trolley having three or more wheels.
[0020] Both of the aforementioned numbers N1 and N2 of gear teeth
of the first and second gears are greater than or equal to 6.
[0021] The aforementioned first, second and third directions of the
bottom frame, upper frame and rear wheel frame are different
directions.
[0022] The sum of the aforementioned third included angle.theta.3
and the fourth included angle.theta.4 falls within a range of
120.degree..about.240.degree..
[0023] The aforementioned first and second gears are independently
separate parts.
[0024] The aforementioned first and second gears are fixedly
attached together.
[0025] The aforementioned linkage gear unit further comprises a
base disposed between the first gear and the second gear, and the
diameter of the base is greater than the diameter of the first
gear.
BRIEF DESCRIPTION OF THE DRAWINGS
[0026] FIG. 1 is a perspective view of a cart of the present
disclosure in an unfolded state;
[0027] FIG. 2 is a perspective view of a rear side of a folding
joint mechanism of FIG. 1;
[0028] FIG. 3 is an exploded view of the folding joint mechanism of
FIG. 1;
[0029] FIG. 4 is an enlarged view of a portion of a linkage gear
unit of FIG. 3;
[0030] FIG. 5 is a cross-sectional view of combination of the
folding joint mechanism of FIG. 1;
[0031] FIG. 6 is a schematic view of another side of the folding
joint mechanism of FIG. 1;
[0032] FIG. 7 is an enlarged view of a portion of a first arc-rack
of a lower frame joint of FIG. 3;
[0033] FIG. 8 is an enlarged view of a portion of a second arc-rack
of an upper frame joint of FIG. 3;
[0034] FIG. 9 is a side view showing the included angle between the
frames in an unfolded state;
[0035] FIG. 10 is a perspective view of a linkage gear unit in
accordance with a second preferred embodiment of the present
disclosure;
[0036] FIG. 11 is a perspective view of a linkage gear unit in
accordance with a third preferred embodiment of the present
disclosure;
[0037] FIG. 12 is another perspective view of another side of a
linkage gear unit in accordance with the third preferred embodiment
of the present disclosure;
[0038] FIGS. 13a-13d are schematic views of different states of
first and second teeth units of the present disclosure; and
[0039] FIGS. 14a-14b are schematic views of another two states of
the first and second teeth units of the present disclosure.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0040] As shown in the drawings, for the purpose of illustration,
the present disclosure is preferably embodied in the constructions,
features and efficiency thereof as following.
[0041] With reference to FIGS. 1 to 6, a cart in the present
disclosure comprises a bottom frame 1, an upper frame 2, a rear
wheel frame 3 and at least a folding joint mechanism 100.
[0042] The lower end of the bottom frame 1 at least is provided
with a front wheel 11, the upper end is connected to a bottom frame
joint 10, and the bottom frame joint 10 has a recess 2 formed at
the lower end of the outer edge of the bottom frame joint 10, a
first opening 13 formed at the upper end of the inner side of the
bottom frame joint 10, and a first arc-rack 14 formed on a portion
of the edge (the upper edge) of the first opening 13.
[0043] The upper end of the upper frame 2 is provided with a handle
21, the lower end is connected to an upper frame joint 20, and the
upper frame joint 20 has a recess 22 formed at the lower end of the
outer edge of the upper frame joint 20, a second opening 23 formed
at the upper end of the inner side of the upper frame joint 20, and
a second arc-rack 24 formed on a portion of the edge (the bottom
edge) of the second opening 23.
[0044] The lower end of the rear wheel frame 3 at least is provided
with a rear wheel 31, the upper end at least is connected to a rear
wheel frame joint 30, and the rear wheel frame joint 30 has a
recess 32 formed at the lower end of the outer edge of the rear
wheel frame joint 30.
[0045] The at least one folding joint mechanism 100 is disposed
among the bottom frame 1, the upper frame 2 and the rear wheel
frame 3, comprising the bottom frame joint 10, the upper frame
joint 20, the rear wheel frame joint 30 and a linkage gear unit 4,
and the linkage gear unit 4 being disposed between the bottom frame
joint 10 and the upper frame joint 20 having mutually separate
first and second gears 41, 42, and the first and second gears 41,
42 axially mounted to a side of the rear wheel frame joint 30 by a
pin 40 and rotating coaxially, the gear 41 positioned to engage the
first arc-rack 14 of the bottom frame joint 10, and the second gear
42 positioned to engage the second arc-rack 24 of the upper frame
joint 20; wherein the numbers N1 and N2 of gear teeth of the first
gear 41, 42 are greater than or equal to 6 and both are positive
integers. The numbers N1 and N2 on the actual product are less than
100. In this embodiment, the number of gear teeth of the first gear
41 can be seven teeth, and the number of gear teeth of the second
gear 42 can be six teeth.
[0046] The at least one folding joint mechanism 100 comprises the
left side and right side folding joint mechanism, the left side and
right side folding joint mechanism may have the same constructions,
with one being the mirror image of the other. It is noteworthy that
the following description is depicted in singular number (side),
but the description will apply to both left and right sides.
[0047] The bottom frame joint 10, the upper frame joint 20 and the
rear wheel frame joint 30 are linear arrangement, combined and
locked fixedly by a fixed threaded device 33, for example a screw,
so that the bottom frame joint 10 locates between the upper frame
joint 20 and the rear wheel frame joint 30, and the recesses 12,
22, 32 thereof are arranged linearly, and the first and second
arc-racks 14, 24 and the linkage gear unit 4 are mutually engaged
to form a gear set.
[0048] The at least one folding joint mechanism 100 located at the
front and rear ends of the rear wheel frame joint 30 is defined
with a control mechanism 5 and a pull buckle 6 respectively, a
first latch is formed by the control mechanism 5 and locked when
the baby stroller is unfolded, and further a second safety lock is
formed by the pull buckle 6 to prevent the unintended folding of
the stroller.
[0049] With reference to FIGS. 7 and 8, the first arc-rack 14 of
the bottom frame joint has a first axel center 140, a first tooth
141 and a second tooth 142 respectively, and the second tooth 142
is adjacent to the first tooth 141, the first tooth 141 has a first
end point connected with the first axel center 140 to form a first
virtual line L1, the second tooth 142 has a second end point
P.sub.2 connected with the first axel center 140 to form a second
virtual line L2, and the second virtual line L2 and the first
virtual line L1 define a first including angle .theta.1. The second
arc-rack 24 has a second axel center 240, a third teeth 243 and a
fourth tooth 244 respectively, and the fourth tooth 244 is adjacent
to the second tooth 243, the third tooth 243 has a third end point
P3 connected with the second axel center 240 to form a fourth
virtual line L4, and the third virtual line L3 and the fourth
virtual line L4 define a second included angle.theta.2.
[0050] As shown in FIGS. 1 and 9, when the cart frame is in a fully
unfolded state, the upper frame 2 extends outwards toward a first
direction d.sub.1, the bottom frame 1 extends outwards toward a
second direction d.sub.2 and the rear wheel frame 3 extends
outwards toward a third direction d.sub.3, and the second direction
d.sub.2 and the third direction d.sub.3 define a third included
angle .theta..sub.3, and the third direction d.sub.3 and the first
direction d.sub.1 define a fourth included angle .theta..sub.4.
[0051] According to the aforementioned construction, the gear
design of the at least one folding joint mechanism 100 must meet
the following relations:
360/.theta..sub.1=N.sub.3, .theta..sub.1>0;
360/.theta..sub.2=N.sub.4, .theta..sub.2>0;
[0052]
(N.sub.2/N.sub.4)*(N.sub.3/N.sub.1)=.theta..sub.4/.theta..sub.3;
and wherein N.sub.3 is the number of gear teeth of the first
arc-rack 14, N.sub.4 is the number of gear teeth of the second
arc-rack 24, and both the numbers N1 and N2 of gear teeth of the
first and second gears 41, 42 are positive integers, and at least
one of the numbers N3 and N4 of gear teeth of the first and second
arc-racks 14, 24 is not a positive integer. The angle of the third
included angle .theta..sub.3 and the fourth included angle
.theta..sub.4 falls within a range of 30.degree..about.150.degree.,
and the sum of .theta..sub.3 and .theta..sub.4 falls within a range
of 120.about.240.degree.. When the sum of the two included angles
falls within this range, the cart with the angle in a full unfolded
state will be more stable.
[0053] In a further example, when the design conditions are
.theta..sub.3=80.degree. and .theta..sub.4=100.degree., selecting
N.sub.1=7, N.sub.2=6 and N.sub.3=30 and meantime N4=20.57 will be
obtained by means of the relations, and wherein N.sub.4 is an
incomplete tooth. In another example, when the design conditions
are .theta..sub.3=80.degree. and.theta..sub.4=100.degree.,
selecting N.sub.1=10, N.sub.2=8 and N.sub.3=40.87 and meantime
N4=26.16 will be obtained by means of the relations, and wherein N3
and N4 are incomplete teeth. In another example, when the design
conditions are.theta..sub.3=85.degree. and.theta..sub.4=95.degree.,
selecting N1=11, N.sub.2=7 and N.sub.4=25 and meantime N.sub.3=43.9
will be obtained by means of the relations, and wherein N.sub.3 is
the incomplete tooth. In effect, the design freedom and flexibility
will be enhanced on the product design.
[0054] In summation of the description above, the present
disclosure has at least one of the following advantages and effects
and has more great advance than the prior art.
[0055] 1. When the angle of rotation in an unfolding or folding
state is unchanged, the contact ratio of the gear and the arc-rack
is increased since the numbers N1 and N2 of gear teeth of the first
and second gears 41, 42 are greater than or equal to 6. Not only
more gear teeth will provide the supporting force but also the
stress exerted on a unit teeth is decreased significantly, so that
the strength of the gear teeth is enhanced, and the service life is
extended effectively.
[0056] 2. Since the numbers of gear teeth of the first and second
gears 41, 42 are greater than or equal to 6, the coaxial rotation
can be achieved, and the number of gear teeth and the modulus of
the gear can be changed, so as to improve the freedom and
flexibility of the gear design significantly.
[0057] 3. Since at least one of the first and second arc-racks 14,
24 is an incomplete tooth, the included angle .theta..sub.1 defined
between the bottom frame 1 and the rear wheel frame 3 can be
changed or adjusted freely, so as to improve the freedom and
flexibility of the frame design.
[0058] With reference to FIG. 10 for the second embodiment of the
linkage gear unit, in this embodiment the linkage gear unit 4' is
composed of the first and second gears 43, 44 and is mounted by a
pin 40 to rotate coaxially, and the first and second gears 43, 44
are fixedly attached together by welding or some other manner for
rotating together as a unit on the pin 44, and wherein the number
of gear teeth of the first gear 43 is seven and the number of gear
teeth of the second gear is six, so that for the purpose of
achieving the same efficacy as the abovementioned first
embodiment.
[0059] With reference to FIGS. 11 and 12 for third embodiment of
the linkage gear unit, the linkage gear unit 4'' comprises a first
and a second gear 45, 46, a base 47 is disposed between the first
and second gears 45, 46, and a pin 40 is provided for the first and
second gears 45, 46 being passed and mounted to the base 47. The
diameter of the base 47 is greater than the diameter of the first
and second gears 45, 46, and includes a notch 471 thereto for
recognizing and installing, so that for the purpose of achieving
the same efficacy as the above mentioned first embodiment.
[0060] With reference to FIGS. 13a.about.13d, 14a, and 14b for the
design of different states related to the first and second teeth in
the first and second arc-racks of the present disclosure, and the
states are embodied for the purpose of depicting the first and
second gear teeth, and the concept related to the two adjacent
teeth can be indicated by means of the adjacent first gear tooth
unit and second gear tooth unit. As shown in FIG. 13a, as long as
the repeatedly representative end point P and virtual line L are
included in the two adjacent gear teeth units, the first gear teeth
unit comprises one large gear teeth and one small gear teeth, and
the second gear teeth unit and the first gear teeth unit are
repeated periodic design, and herewith the included angle .theta.
of the gear teeth units is calculated from the repeated points of
the first gear teeth unit and the second teeth gear unit, that is
the disclosure can be implemented with the condition of a periodic
unit with an effective contact.
* * * * *