[0001] The invention relates to a modular tube assembly, more particularly to a modular
tube assembly for assembling tubular furniture parts.
[0002] As shown in Figure 1, a conventional tube assembly includes a pair of upright tubes
11, and a plurality of connecting rods 12 interconnecting the upright tubes 11. The
opposite ends of each of the connecting rods 12 are generally and respectively welded
to the upright tubes 11. However, it is troublesome to have the opposite ends of each
connecting rod 12 welded respectively and precisely to selected positions of the upright
tubes 11. Moreover, the conventional tube assembly can not be disassembled, thereby
resulting in inconvenience when transporting the conventional tube assembly.
[0003] Referring to Figure 2, a conventional modular tube assembly includes a pair of upright
tubes 121, a plurality of connecting rods 122 interconnecting the upright tubes 121,
and a plurality of securing bolts 123 for securing opposite ends of the connecting
rods 122 to the respective upright tubes 121. Each of the upright tubes 121 has a
plurality of depressed portions 1211 corresponding in position to the connecting rods
122, respectively, and a plurality of through holes 1212 formed respectively in the
depressed portions 1211. Each of the securing bolts 123 is disposed to extend through
a respective one of the depressed portions 1211 of a respective one of the upright
tubes 121 and into an end of a respective one of the connecting rods 122. However,
it is still inconvenient to assemble this conventional modular tube assembly using
the securing bolts 123.
[0004] Therefore, the object of the present invention is to provide a modular tube assembly
that is easy to assemble.
[0005] Accordingly, a modular tube assembly of the present invention comprises first and
second upright tubes and at least one connecting rod unit. The first and second upright
tubes are spaced apart from each other. Each of the first and second upright tubes
is formed with at least one engaging hole. The at least one engaging hole of the first
upright tube is registered with the at least one engaging hole of the second upright
tube. The at least one connecting rod unit includes a connecting rod and at least
one spring-loaded pin. The connecting rod interconnects the first and second upright
tubes, and has a first end that corresponds in position to the at least one engaging
hole of the first upright tube, and a second end that is longitudinally opposite to
the first end and that corresponds in position to the at least one engaging hole of
the second upright tube. The at least one spring-loaded pin has a securing portion
that is secured to one of the first and second ends of the connecting rod, and a movable
portion that is movable resiliently relative to the securing portion and that engages
removably the at least one engaging hole of a respective one of the first and second
upright tubes.
[0006] Other features and advantages of the present invention will become apparent in the
following detailed description of the preferred embodiments with reference to the
accompanying drawings, of which:
Fig. 1 is a fragmentary perspective view of a conventional tube assembly;
Fig. 2 is fragmentary schematic sectional view of a conventional modular tube assembly;
Fig. 3 is a fragmentary assembled perspective view of a first preferred embodiment
of a modular tube assembly according to the invention;
Fig. 4 is a fragmentary exploded perspective view of the first preferred embodiment;
Fig. 5 is a fragmentary partly sectional view of the first preferred embodiment, illustrating
a movable portion of a spring-loaded pin at a retracted position;
Fig. 6 is a view similar to Fig. 5, but illustrating the movable portion at an extended
position;
Fig. 7 is a fragmentary exploded perspective view of a second preferred embodiment
of the modular tube assembly according to the invention;
Fig. 8 is a fragmentary partly sectional view of the second preferred embodiment,
illustrating a movable portion of a spring-loaded pin at a retracted position;
Fig. 9 is a view similar to Fig. 8, but illustrating the movable portion at an extended
position;
Fig. 10 is a fragmentary partly sectional view of a third preferred embodiment of
the modular tube assembly according to the invention;
Fig. 11 is a fragmentary partly exploded perspective view of a fourth preferred embodiment
of the modular tube assembly according to the invention; and
Fig. 12 is a fragmentary partly sectional view of the fourth preferred embodiment.
[0007] Before the present invention is described in greater detail, it should be noted that
like elements are denoted by the same reference numerals throughout the disclosure.
[0008] As shown in Figures 3 to 5, the first preferred embodiment of a modular tube assembly
according to the present invention is adapted for connecting metallic tubular parts
of furniture, such as bedsteads, chairs, cabinets, and so on. The modular tube assembly
comprises an upright tube unit 2, a pair of coupling rods 3, and a plurality of connecting
rod units 40.
[0009] The upright tube unit 2 includes first and second upright tubes 21, 22 spaced apart
from each other. The first upright tube 21 is formed with a plurality of longitudinally
spaced-apart first engaging holes 211, and a pair of first positioning holes 212 that
are formed respectively above and below the first engaging holes 211. The second upright
tube 22 is formed with a plurality of longitudinally spaced-apart second engaging
holes 221 that are registered respectively with the first engaging holes 211 of the
first upright tube 21, and a pair of second positioning holes 222 that are formed
respectively above and below the second engaging holes 221 and that are registered
respectively with the first positioning holes 212. Each of the first and second positioning
holes 212, 222 has a main hole portion 213, 223, and an extending hole portion 214,
224 extending downwardly from and having a width smaller than that of the main hole
portion 213, 223.
[0010] In this embodiment, one of the coupling rods 3 has a first end portion engaging the
upper one of the first positioning holes 212 of the first upright tube 21, and a second
end portion longitudinally opposite to the first end portion and engaging the corresponding
one of the second positioning holes 222 of the second upright tube 22. The other one
of the coupling rods 3 has a first end portion engaging the lower one of the first
positioning holes 212, and a second end portion longitudinally opposite to the first
end portion and engaging the corresponding one of the second positioning holes 222.
Each of the coupling rods 3 has a main part 31 having longitudinally opposite ends
that are connected respectively to the first and second end portions. Each of the
first and second end portions has a neck part 32 that has a cross-section smaller
than the extending hole portion 214, 224 of a corresponding one of the first and second
positioning holes 212, 222, that extends through the extending hole portion 214, 224
of the corresponding one of the first and second positioning holes 212, 222, and that
has an inner end connected to a respective one of the ends of the main part 31 and
an outer end longitudinally opposite to the inner end. Each of the first and second
end portions further has a head part 33 that is connected to the outer end of the
neck part 32, and that has a cross-section larger than the extending hole portion
214, 224 of the corresponding one of the first and second positioning holes 212, 222.
[0011] Each of the connecting rod units 40 includes a connecting rod 4 and a spring-loaded
pin 5.
[0012] The connecting rod 4 of each of the connecting rod units 40 interconnects the first
and second upright tubes 21, 22, and has first and second ends that correspond respectively
in position to a respective pair of the registered first and second engaging holes
211, 221. In this embodiment, each connecting rod 4 has a hollow connecting segment
41 formed at the first end thereof and having a cross-section smaller than that of
the corresponding one of the first engaging holes 211, a main segment 42 connected
to the connecting segment 41, and an insert segment 43 formed at the second end thereof,
and connected to and having a cross-section smaller than that of the main segment
42. In this embodiment, the cross-section of the insert segment 43 of each connecting
rod 4 is elongated and configured to be substantially identical to the corresponding
one of the second engaging holes 221 such that the insert segment 43 of each connecting
rod 4 can be separably and non-rotatably inserted into the corresponding one of the
second engaging holes 221. The cross-section of each insert segment 43 and the shape
of each second engaging hole 221 may be configured to be other non-circular shapes
in other embodiments of this invention.
[0013] The spring-loaded pin 5 of each connecting rod unit 40 has a securing portion 51,
a movable portion 52, and a spring member 53. The securing portion 51 has a cross-section
smaller than that of the connecting segment 41 of a respective one of the connecting
rods 4 so as to be inserted thereinto and be secured thereto. The securing portion
51 includes an inner wall 511 disposed in the connecting segment 41 of the corresponding
connecting rod 4, a hollow outer wall 512 spaced longitudinally apart from the inner
wall 511 and connected to the first end of the corresponding connecting rod 4, and
an intermediate wall 513 interconnecting the inner and outer walls 511, 512. The movable
portion 52 is disposed movably in the securing portion 51 and extends movably through
the outer wall 512. The spring member 53 is a compression spring disposed in the securing
portion 51 and having opposite ends that abut respectively and resiliently against
the inner wall 511 and the movable portion 52.
[0014] Referring once again to Figures 4 and 5, and further referring to Figure 6, when
assembling the modular tube assembly of this invention, each coupling rod 3 has to
be placed at a position where the head parts 33 thereof are extended respectively
through the main hole portions 213, 223 of the corresponding first and second positioning
holes 212, 222, and then moved downwardly until the neck parts 32 thereof engage respectively
the extending hole portions 214, 224 of the corresponding first and second positioning
holes 212, 222, such that the coupling rods 3 are connected to the upright tube unit
2 and that the first and second upright tubes 21, 22 are positioned relative to each
other. Afterward, when coupling each connecting rod unit 40 to the upright tube unit
2, the first end of the connecting rod 4 is inserted into the corresponding first
engaging hole 211 and further pushed inwardly so that the movable portion 52 is urged
by an inner surface of the first upright tube 21 to retract from an extended position
(see Figure 6), where the distal end of the movable portion 52 is away from the inner
wall 511 of the securing portion 51, to a retracted position (see Figure 5), where
the distal end of the movable portion 52 is close to the inner wall 511, against the
resilient force of the spring member 53, thereby permitting the insert segment 43
to be disposed at a position between the first and second upright tubes 21, 22 and
adjacent to the corresponding second engaging hole 221. Finally, the connecting rod
4 is moved longitudinally toward the second upright tube 22 to insert the insert segment
43 fittingly into the corresponding second engaging hole 221, and the movable portion
52 is released to move resiliently back to the extended position by the restoring
force of the spring member 53 while the connecting segment 41 still engages the corresponding
first engaging hole 211 so as to complete the coupling of the connecting rod unit
40 to the upright tube unit 2.
[0015] On the contrary, each connecting rod unit 40 can be removed by moving the connecting
rod 4 to thereby move the movable portion 52 to the retracted position, and disengaging
the insert segment 43 from the corresponding second engaging hole 221.
[0016] Compared to the abovementioned conventional modular tube assembly, each of the connecting
rod units 40 of this invention has a simpler structure, and can be easily and quickly
coupled to and removed from the upright tube unit 2 without the use of any tool. In
addition, the presence of the coupling rods 3 further enhances the structural stability
of the upright tube unit 2 while being coupled with the connecting rod units 40.
[0017] Referring to Figures 7 to 9, the second preferred embodiment of the modular tube
assembly according to the present invention has a structure similar to that of the
first embodiment. The main difference between this embodiment and the previous embodiment
resides in that each first engaging hole 211 is larger than the cross-section of the
movable portion 52 of the corresponding spring-loaded pin 5, but is smaller than the
cross-section of the connecting segment 41 of the corresponding connecting rod 4.
[0018] Each connecting rod unit 40 is assembled to the upright tube unit 2 by inserting
the insert segment 43 into the corresponding second engaging hole 221, and moving
the connecting rod 4 together with the corresponding spring-loaded pin 5 toward the
corresponding first engaging hole 211. During the movement of the connecting rod 4
toward the corresponding first engaging hole 211, the movable portion 52 is urged
by an outer surface of the first upright tube 21 to the retracted position, and slides
along the outer surface. When the movable portion 52 is moved to the corresponding
first engaging hole 211 (see Figure 8), it is biased by the restoring force of the
spring member 53 to the extended position (see Figure 9) to engage the corresponding
first engaging hole 211, thereby completing the coupling of the connecting rod unit
40 to the upright tube unit 2. To disassemble each connecting rod unit 40 from the
upright tube unit 2, the coupling rods 3 have to be removed from the upright rod unit
2 first so that the first upright tube 21 can be moved away from the second upright
tube 22, thereby permitting the removal of the connecting rod units 40. The second
preferred embodiment has the same advantages as those of the first preferred embodiment.
[0019] As shown in Figure 10, the third preferred embodiment of the modular tube assembly
according to the present invention has a structure similar to that of the first preferred
embodiment. The main difference between this embodiment and the first preferred embodiment
resides in the configuration of the connecting rod unit 40. The connecting rod 4 of
each connecting rod units 40 has a symmetrical structure that includes the main segment
42 and two connecting segments 41 formed respectively at the first and second ends
of the connecting rod 4, connected respectively to opposite ends of the main segment
42, and corresponding respectively in position to the respective pair of the registered
first and second engaging holes 211, 221. Two spring-loaded pins 5 are provided to
be inserted respectively into the connecting segments 41. Each second engaging hole
221 of the second upright tube 22 is formed as a round hole larger than the cross-section
of the respective connecting segment 41.
[0020] Each connecting rod unit 40 can be coupled to the upright tube unit 2 by inserting
one of the first and second ends of the connecting rod 4 into the corresponding first
or second engaging hole 211, 221, pushing the movable portion 52 of the corresponding
spring-loaded pin 5 to the retracted position, and then moving the connecting rod
4 longitudinally to extend the other one of the first and second ends thereof into
the corresponding first or second engaging hole 211, 221, such that the retracted
movable portion 52 of the spring-loaded pin 5 in the one of the first and second ends
of the connecting rod 4 is released to move back to the extended position, thereby
finishing the coupling of the connecting rod unit 40 to the upright tube unit 2. The
third preferred embodiment has the same advantages as those of the first preferred
embodiment.
[0021] Referring to Figures 11 and 12, the fourth preferred embodiment of the modular tube
assembly according to the present invention has a structure similar to that of the
second embodiment. The main difference between this embodiment and the previous embodiment
resides in the configuration of the connecting rods 4. In this embodiment, each connecting
rod 4 is a straight rod without the connecting segment 41 and the insert segment 43
that are illustrated in the second preferred embodiment. The modular tube assembly
further comprises a plurality of U-shaped support frames 6. Each support frame 6 is
connected to four connecting rods 4, and has a first side portion connected to the
first ends of the connecting rods 4 and a second side portion connected to the second
ends of the connecting rods 4. The first side portion of each support frame 6 is mounted
with four of the spring-loaded pins 5 in a manner that the securing portions 51 thereof
are secured to the first side portion at positions corresponding to the connecting
rods 4, and that the movable portions 52 thereof engage respectively and separably
the corresponding first engaging holes 211. The second side portion of each support
frame 6 is mounted with four insert members 61 that correspond in position to the
second ends of the connecting rods 4, and that engage respectively, separably and
non-rotatably the corresponding second engaging holes 221. By coupling the insert
members 61 to the corresponding second engaging holes 221, and sliding the movable
portions 52 along the outer surface of the first upright tube 21 to engage respectively
the corresponding first engaging holes 211, each support frame 6, together with the
corresponding connecting rods 4 and the spring-loaded pins 5, can be assembled to
the upright tube unit 2. Each support frame 6 can be removed from the upright tube
unit 2 after the removal of the coupling rods 3 from the upright rod unit 2.
1. A modular tube assembly including
first and second upright tubes (21, 22) spaced apart from each other, each of said
first and second upright tubes (21, 22) being formed with at least one engaging hole
(211, 221), said at least one engaging hole (211) of said first upright tube (21)
being registered with said at least one engaging hole (221) of said second upright
tube (22),
characterized in that said modular tube assembly further includes at least one connecting rod unit (40)
including:
a connecting rod (4) interconnecting said first and second upright tubes (21, 22),
and having a first end that corresponds in position to said at least one engaging
hole (211) of said first upright tube (21), and a second end that is longitudinally
opposite to said first end and that corresponds in position to said at least one engaging
hole (221) of said second upright tube (22); and
at least one spring-loaded pin (5) having a securing portion (51) that is secured
to one of said first and second ends of said connecting rod (4), and a movable portion
(52) that is movable resiliently relative to said securing portion (51) and that engages
removably said at least one engaging hole (211, 221) of a respective one of said first
and second upright tubes (21, 22).
2. The modular tube assembly as claimed in claim 1, further
characterized in that:
said first upright tube (21) is further formed with at least one first positioning
hole (212);
said second upright tube (22) is further formed with at least one second positioning
hole (222); and
said modular tube assembly further includes at least one coupling rod (3) having a
first end portion that engages said at least one of said first positioning hole (212),
and a second end portion that is longitudinally opposite to said first end portion
and that engages said at least one of said second positioning hole (222).
3. The modular tube assembly as claimed in claim 2, further
characterized in that:
each of said first and second positioning holes (212, 222) has a main hole portion
(213, 223), and an extending hole portion (214, 224) extending downwardly from and
having a width smaller than said main hole portion (213, 223);
said at least one coupling rod (3) has a main part (31) having longitudinally opposite
ends that are connected respectively to said first and second end portions, each of
said first and second end portions having
a neck part (32) that has a cross-section smaller than said extending hole portion
(214, 224) of a respective one of said first and second positioning holes (212, 222),
that extends through said extending hole portion (214, 224) of the respective one
of said first and second positioning holes (212, 222), and that has an inner end connected
to a respective one of said ends of said main part (31) and an outer end longitudinally
opposite to said inner end, and
a head part (33) that is connected to said outer end of said neck part (32), and that
has a cross-section larger than said extending hole portion (214, 224) of the respective
one of said first and second positioning holes (212, 222).
4. The modular tube assembly as claimed in any one of claims 2 and 3, further characterized in that said first and second positioning holes (212, 222) are formed above said first and
second engaging holes (211, 221).
5. The modular tube assembly as claimed in any one of claims 2 and 3, further characterized in that said first and second positioning holes (212, 222) are formed below said first and
second engaging holes (211, 221).
6. The modular tube assembly as claimed in any one of the previous claims, further characterized in that said connecting rod (4) of said at least one connecting rod unit (40) has
at least one connecting segment (41) formed at one of said first and second ends thereof,
and secured to and having a cross-section larger than that of said securing portion
(51) of said at least one spring-loaded pin (5), and
a main segment (42) connected to said at least one connecting segment (41).
7. The modular tube assembly as claimed in claim 6, further
characterized in that:
said at least one connecting rod unit (40) includes one of said spring-loaded pin
(5); and
said connecting rod (4) has one of said connecting segment (41) formed at said first
end thereof, and an insert segment (43) formed at said second end thereof, connected
to said main segment (42), having a cross-section smaller than that of said main segment
(42), and inserted separably into said at least one engaging hole (221) of said second
upright tube (22).
8. The modular tube assembly as claimed in claim 7, further characterized in that the cross-section of said insert segment (43) of said connecting rod (4) is configured
to be substantially identical to said at least one engaging hole (221) of said second
upright tube (22) such that said connecting rod (4) is inserted separably and non-rotatably
into said at least one engaging hole (221) of said second upright tube (22).
9. The modular tube assembly as claimed in claim 8, further characterized in that said at least one engaging hole (221) of said second upright tube (22) is formed
as an elongated hole, and said insert segment (43) of said connecting rod (4) has
an elongated cross-section.
10. The modular tube assembly as claimed in any one of claims 6 to 9, further characterized in that said at least one connecting segment (41) of said connecting rod (4) of said at least
one connecting rod unit (40) has a cross-section smaller than a corresponding one
of said engaging holes (211, 221) in said first and second upright tubes (21, 22).
11. The modular tube assembly as claimed in any one of claims 6 to 9, further
characterized in that:
said at least one connecting segment (41) of said connecting rod (4) of said at least
one connecting rod unit (40) has a cross-section larger than said at least one engaging
hole (211, 221) of the respective one of said first and second upright tubes (21,
22); and
said movable portion (52) of said at least one spring-loaded pin (5) of said at least
one connecting rod unit (40) has a cross-section smaller than said at least one engaging
hole (211, 221) of the respective one of said first and second upright tubes (21,
22).
12. The modular tube assembly as claimed in claim 1, further
characterized in that:
said modular tube assembly includes a plurality of said connecting rod units (40),
and further includes at least one support frame (6) that has a first side portion
connected to said first ends of said connecting rods (4) and a second side portion
connected to said second ends of said connecting rods (4);
each of said first and second upright tubes (21, 22) is formed with a plurality of
said engaging holes (211, 221); and
said securing portions (51) of said spring-loaded pins (5) of said connecting rod
units (40) are secured to said first side portion of said at least one support frame
(6) and engage removably and respectively said engaging holes (211, 221) of a respective
one of said first and second upright tubes (21, 22).
13. The modular tube assembly as claimed in claim 12, further characterized in that said second side portion of said at least one support frame (6) is provided with
a plurality of insert members (61) that engage separably and respectively said engaging
holes (221) of said second upright tube (22).
14. The modular tube assembly as claimed in claim 13, further characterized in that said insert members (61) of said at least one support frame (6) has a cross-section
configured to be substantially identical to said engaging holes (221) of said second
upright tube (22) such that said insert members (61) are inserted separably and non-rotatably
into said engaging holes (221) of said second upright tube (22).
15. The modular tube assembly as claimed in any one of the previous claims, wherein:
said securing portion (51) of said at least one spring-loaded pin (5) of said at least
one connecting rod unit includes
an inner wall (511) disposed in said connecting rod (4),
a hollow outer wall (512) spaced apart from said inner wall (511) and connected to
a corresponding one of said first and second ends of said connecting rod (4), and
an intermediate wall (513) interconnecting said inner and outer walls (511, 512);
said movable portion (52) of said at least one spring-loaded pin (5) of said at least
one connecting rod unit (40) extends movably through said outer wall (512); and
said at least one spring-loaded pin (5) further includes a spring member (513) disposed
in said securing portion (51) and having opposite ends that abut respectively and
resiliently against said inner wall (511) and said movable portion (52).