U.S. patent application number 10/301032 was filed with the patent office on 2003-04-24 for patio tabletop glass with broken protection.
Invention is credited to Liao, Cheng Kun.
Application Number | 20030077416 10/301032 |
Document ID | / |
Family ID | 26901802 |
Filed Date | 2003-04-24 |
United States Patent
Application |
20030077416 |
Kind Code |
A1 |
Liao, Cheng Kun |
April 24, 2003 |
Patio tabletop glass with broken protection
Abstract
A patio tabletop glass with broken protection includes a
tempered glass layer wherein a central hole is formed in the
tempered glass layer; a protection layer which has a shape and
width size identical to that of the tempered glass layer being
integrally attached on a top surface of the tempered glass layer
and having a center hole formed therein, wherein the center hole of
the protection layer has an identical diameter of the central hole
of the tempered glass layer and is coaxially aligned with the
central hole of the tempered glass layer; and an adhesive layer
which is evenly applied between the top surface of the tempered
glass layer and a bottom surface of the protection layer so as to
integrally adhere the protection layer with the tempered glass
layer to form an one piece body, wherein a tension of a periphery
portion of the protection layer is increased to form a protective
edge of the center hole, which is made to extend around the central
hole of the tempered glass layer and to ensure the periphery
portion of the protection layer around the center hole securely
attached around the central hole on the tempered glass layer.
Inventors: |
Liao, Cheng Kun; (S. El
Monte, CA) |
Correspondence
Address: |
Raymond Y. Chan
Suite 128
108 N. Ynez Avenue
Monterey Park
CA
91754
US
|
Family ID: |
26901802 |
Appl. No.: |
10/301032 |
Filed: |
November 20, 2002 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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10301032 |
Nov 20, 2002 |
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09650253 |
Aug 29, 2000 |
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6503357 |
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09650253 |
Aug 29, 2000 |
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09206922 |
Dec 7, 1998 |
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Current U.S.
Class: |
428/66.6 ;
428/137; 428/426 |
Current CPC
Class: |
Y10T 428/24322 20150115;
B29C 2063/485 20130101; Y10T 156/108 20150115; B29C 63/0086
20130101; Y10T 156/1057 20150115; B29L 2031/448 20130101; Y10T
428/218 20150115; Y10T 428/24273 20150115; Y10T 428/24967
20150115 |
Class at
Publication: |
428/66.6 ;
428/137; 428/426 |
International
Class: |
B32B 003/02 |
Claims
What is claimed is:
1. A patio tabletop glass, comprising: a tempered glass layer
having a predetermined shape, a predetermined thickness and a
predetermined width size, wherein a central hole is formed in said
tempered glass layer; a protection layer having a shape and width
size identical to that of said tempered glass layer, said
protection layer being integrally attached on a top surface of said
tempered glass layer and having a center hole formed therein,
wherein said center hole of said protection layer has an identical
diameter of said central hole of said tempered glass layer and is
coaxially aligned with said central hole of said tempered glass
layer; and an adhesive layer which is evenly applied between said
top surface of said tempered glass layer and a bottom surface of
said protection layer so as to integrally adhere said protection
layer with said tempered glass layer to form an one piece body,
wherein a tension of a periphery portion of said protection layer
is increased to form a protective edge of said center hole, which
is made to extend around said central hole of said tempered glass
layer and to ensure said periphery portion of said protection layer
around said center hole securely attached around said central hole
on said tempered glass layer.
2. A patio tabletop glass, as recited in claim 1, wherein said
protection layer having a thickness of 0.3 to 0.8 mm,
3. A patio tabletop glass, as recited in claim 1, wherein said top
surface of said tempered glass layer is an uneven top surface
having specific decorative pattern.
4. A patio tabletop glass, as recited in claim 2, wherein said
tempered glass layer has an uneven top surface having specific
decorative pattern.
5. A patio tabletop glass, as recited in claim 1, wherein said
patio tabletop glass is manufactured by the steps of: (a) fully
cleaning said top surface of said tempered glass layer; (b) drying
said tempered glass layer after cleaning; (c) heating said entire
tempered glass layer to a predetermined adhering temperature; (d)
evenly applying a layer of acrylic adhesive on said top surface of
said tempered glass layer which temperature is maintained at said
predetermined adhering temperature to form said adhesive layer; (e)
attaching said protection layer on top of said adhesive layer of
said tempered glass layer by pressing said protection layer against
said top surface of said tempered glass layer which is maintained
at said predetermined adhering temperature until said protection
layer is integrally attached on said tempered glass' layer, wherein
said protection layer has a circular center portion formed above
said central hole of said tempered glass layer; (f) cutting
excessive edges of said protection layer to a size identical to
said tempered glass layer; (g) pressing said center portion of said
protection layer toward said central hole of said tempered glass
layer to increase a tension of a peripheral portion of said
protection layer around said central hole of said tempered glass
layer and to extend and attach said protection layer to an upper
edge of said central hole of said tempered glass layer; and (h)
grinding said upper edge of said central hole of said tempered
glass layer until said center portion of said protection layer is
separated from said protection layer to form a center hole
coaxially aligned with said central hole of said tempered glass
layer.
6. A patio tabletop glass, as recited in claim 5, wherein said
predetermined adhering temperature is between 45.degree. C. to
65.degree. C.
7. A patio tabletop glass, as recited in claim 5, wherein the step
(a) further comprises the steps of cutting a large piece of glass
board to form a circular shaped glass layer, drilling said central
hole in said glass layer and tempering said glass layer by heating
said glass layer to about 500.degree. C.-550.degree. C. and then
immediately cooling down to 0.degree. C.-40.degree. C. to form said
tempered glass layer.
8. A patio tabletop glass, as recited in claim 5, wherein, in the
step (g), said center portion of said protection layer is pressed
by a press mold, which has a round shaped presser head at one end
thereof, towards said central hole of said tempered glass layer,
wherein an inward pressing force of said pressing head further
presses said peripheral portion of said protection layer to extend
and attach to said upper edge of said central hole of said tempered
glass layer.
9. A patio tabletop glass, as recited in claim 5, wherein, in the
step (h), a rotating sand wheel is used to grind at a position of
said corresponding upper edge of said central hole so as to reduce
said thickness of said peripheral edge of said center portion until
said center portion of said protection layer is separated from said
protection layer to form said center hole coaxially aligned with
said central hole of said tempered glass layer.
10. A patio tabletop glass, as recited in claim 5, wherein, in the
step (a), said top surface of said tempered glass layer is cleaned
with neutral water having a pH of 7.
11. A patio tabletop glass, as recited in claim 2, wherein said
patio tabletop glass is manufactured by the steps of: (a) fully
cleaning said top surface of said tempered glass layer; (b) drying
said tempered glass layer after cleaning; (c) heating said entire
tempered glass layer to a predetermined adhering temperature
between 45.degree. C. to 65.degree. C.; (d) evenly applying a layer
of acrylic adhesive on said top surface of said tempered glass
layer which temperature is maintained at said predetermined
adhering temperature to form said adhesive layer; (e) attaching
said protection layer on top of said adhesive layer of said
tempered glass layer by pressing said protection layer against said
top surface of said tempered glass layer which is maintained at
said predetermined adhering temperature until said protection layer
is integrally attached on said tempered glass layer, wherein said
protection layer has a circular center portion formed above said
central hole of said tempered glass layer; (f) cutting excessive
edges of said protection layer to a size identical to said tempered
glass layer; (g) pressing said center portion of said protection
layer toward said central hole of said tempered glass layer to
increase a tension of a peripheral portion of said protection layer
around said central hole of said tempered glass layer and to extend
and attach said protection layer to an upper edge of said central
hole of said tempered glass layer; and (h) grinding said upper edge
of said central hole of said tempered glass layer until said center
portion of said protection layer is separated from said protection
layer to form a center hole coaxially aligned with said central
hole of said tempered glass layer.
12. A patio tabletop glass, as recited in claim 11, wherein the
step (a) further comprises the steps of cutting a large piece of
glass board to form a circular shaped glass layer, drilling said
central hole in said glass layer and tempering said glass layer by
heating said glass layer to about 500.degree. C.-550.degree. C. and
then immediately cooling down to 0.degree. C.-40.degree. C. to form
said tempered glass layer.
13. A patio tabletop glass, as recited in claim 12, wherein, in the
step (g), said center portion of said protection layer is pressed
by a press mold, which has a round shaped presser head at one end
thereof, towards said central hole of said tempered glass layer,
wherein an inward pressing force of said pressing head further
presses said peripheral portion of said protection layer to extend
and attach to said upper edge of said central hole of said tempered
glass layer.
14. A patio tabletop glass, as recited in claim 13, wherein, in the
step (h), a rotating sand wheel is used to grind at a position of
said corresponding upper edge of said central hole so as to reduce
said thickness of said peripheral edge of said center portion until
said center portion of said protection layer is separated from said
protection layer to form said center hole coaxially aligned with
said central hole of said tempered glass layer.
15. A patio tabletop glass, as recited in claim 11, wherein, in the
step (a), said top surface of said tempered glass layer is cleaned
with neutral water having a pH of 7.
16. A patio tabletop glass, as recited in claim 4, wherein said
patio tabletop glass is made by the steps of: (a) fully cleaning
said top surface of said tempered glass layer; (b) drying said
tempered glass layer after cleaning; (c) heating said entire
tempered glass layer to a predetermined adhering temperature
between 45.degree. C. to 65.degree. C.; (d) evenly applying a layer
of acrylic adhesive on said top surface of said tempered glass
layer which temperature is maintained at said predetermined
adhering temperature to form said adhesive layer; (e) attaching
said protection layer on top of said adhesive layer of said
tempered glass layer by pressing said protection layer against said
top surface of said tempered glass layer which is maintained at
said predetermined adhering temperature until said protection layer
is integrally attached on said tempered glass layer, wherein said
protection layer has a circular center portion formed above said
central hole of said tempered glass layer; (f) cutting excessive
edges of said protection layer to a size identical to said tempered
glass layer; (g) pressing said center portion of said protection
layer toward said central hole of said tempered glass layer to
increase a tension of a peripheral portion of said protection layer
around said central hole of said tempered glass layer and to extend
and attach said protection layer to an upper edge of said central
hole of said tempered glass layer; and (h) grinding said upper edge
of said central hole of said tempered glass layer until said center
portion of said protection layer is separated from said protection
layer to form a center hole coaxially aligned with said central
hole of said tempered glass layer.
17. A patio tabletop glass, as recited in claim 16, wherein the
step (a) further comprises the steps of cutting a large piece of
glass board to form a circular shaped glass layer, drilling said
central hole in said glass layer and tempering said glass layer by
heating said glass layer to about 500.degree. C.-550.degree. C. and
then immediately cooling down to 0.degree. C.-40.degree. C. to form
said tempered glass layer.
18. A patio tabletop glass, as recited in claim 17, wherein, in the
step (g), said center portion of said protection layer is pressed
by a press mold, which has a round shaped presser head at one end
thereof, towards said central hole of said tempered glass layer,
wherein an inward pressing force of said pressing head further
presses said peripheral portion of said protection layer to extend
and attach to said upper edge of said central hole of said tempered
glass layer.
19. A patio tabletop glass, as recited in claim 18, wherein, in the
step (h), a rotating sand wheel is used to grind at a position of
said corresponding upper edge of said central hole so as to reduce
said thickness of said peripheral edge of said center portion until
said center portion of said protection layer is separated from said
protection layer to form said center hole coaxially aligned with
said central hole of said tempered glass layer.
20. A patio tabletop glass, as recited in claim 19, wherein, in the
step (a), said top surface of said tempered glass layer is cleaned
with neutral water having a pH of 7.
21. A patio tabletop glass, as recited in claim 11, wherein in the
step (e) said adhesive layer has a thickness of 0.1 to 0.2 mm.
22. A patio tabletop glass, as recited in claim 19, wherein in the
step (e) said adhesive layer has a thickness of 0.1 to 0.2 mm.
23. A patio tabletop glass which is made by the steps of: (a) fully
cleaning at least a top surface of a tempered glass layer having a
central hole thereon; (b) drying said tempered glass layer after
cleaning; (c) heating said entire tempered glass layer to a
predetermined adhering temperature; (d) evenly applying a layer of
acrylic adhesive on said top surface of said tempered glass layer
which temperature is maintained at said predetermined adhering
temperature to form an adhesive layer; (e) attaching said
protection layer having a width size larger than said tempered
glass layer on top of said adhesive layer of said tempered glass
layer by pressing said protection layer against said top surface of
said tempered glass layer which is maintained at said predetermined
adhering temperature until said protection layer is integrally
attached on said tempered glass layer, wherein said protection
layer has a circular center portion formed above said central hole
of said tempered glass layer; (f) cutting excessive edges of said
protection layer to a size identical to said tempered glass layer;
(g) pressing said center portion of said protection layer toward
said central hole of said tempered glass layer to increase a
tension of a peripheral portion of said protection layer around
said central hole of said tempered glass layer and to extend and
attach said protection layer to an upper edge of said central hole
of said tempered glass layer; and (h) grinding said upper edge of
said central hole of said tempered glass layer until said center
portion of said protection layer is separated from said protection
layer to form a center hole coaxially aligned with said central
hole of said tempered glass layer.
24. A patio tabletop glass, as recited in claim 23, wherein said
predetermined adhering temperature is between 45.degree. C. to
65.degree. C.
25. A patio tabletop glass, as recited in claim 23, wherein said
protection layer has a thickness of 0.3 to 0.8 mm.
26. A patio tabletop glass, as recited in claim 24, wherein said
protection layer has a thickness of 0.3 to 0.8 mm.
27. A patio tabletop glass, as recited in claim 24, wherein said
step (a) further comprises said steps of cutting a large piece of
glass board to form a circular shaped glass layer having a specific
decorative pattern provided on at least said top surface, drilling
said central hole in said glass layer and tempering said glass
layer by heating said glass layer to about 500.degree.
C.-550.degree. C. and then immediately cooling down to 0.degree.
C.-40.degree. C. to form said tempered glass layer.
28. A patio tabletop glass, as recited in claim 27, wherein said
adhesive layer has a thickness of 0.1 to 0.2 mm.
29. A patio tabletop glass, as recited in claim 28, wherein, in the
step (g), said center portion of said protection layer is pressed
by a press mold, which has a round shaped presser head at one end
thereof, towards said central hole of said tempered glass layer,
wherein an inward pressing force of said pressing head further
presses said peripheral portion of said protection layer to extend
and attach to said upper edge of said central hole of said tempered
glass layer.
30. A patio tabletop glass, as recited in claim 29, wherein, in the
step (h), a rotating sand wheel is used to grind at a position of
said corresponding upper edge of said central hole so as to reduce
said thickness of said peripheral edge of said center portion until
said center portion of said protection layer is separated from said
protection layer to form said center hole coaxially aligned with
said central hole of said tempered glass layer.
31. A patio tabletop glass, as recited in claim 30, wherein, in
step (a), said top surface of said tempered glass layer is cleaned
with neutral water having a pH of 7.
Description
CROSS REFERENCE OF RELATED APPLICATION
[0001] This is a Divisional Application of a Non-Provisional
Application, application number 09/650,253, filed Aug. 29, 2000,
which is a Continuation-In-Part Application of a non-provisional
application, application number 09/206,922, filed Dec. 07,
1998.
FIELD OF THE PRESENT INVENTION
[0002] The present invention relates to an outdoor tabletop glass,
and more particularly to a manufacturing process of patio tabletop
glass with broken protection to prevent the broken: glass particles
from hurting the users when the patio tabletop glass is
accidentally broken.
BACKGROUND OF THE PRESENT INVENTION
[0003] Patio table is one of the most popular outdoor furniture,
which normally is placed in the patio or the back yard for the
users to rest and serve barbecue. For easy clean, decorating and
other reasons, most patio table has a glass made tabletop. The
tabletop glass, which is simply placed on top of a table frame,
generally has a central hole adapted to hold an umbrella in
position for sunshine shading.
[0004] The biggest shortcoming of the patio tabletop glass is its
fragile nature especially when using outdoors. It is reported that
even though most of the patio tabletop glasses are made of tempered
glass, the patio tabletop glass may be broken when its surface is
impacted with a sharp object; when it hardly falls on ground; or
when a small stone hits on it in high speed. The central hole of
the patio tabletop glass is the most weakened area because of the
high concentrate stress occurred around the hole. Besides, when
wild wind blows on the opened umbrella, it may cause the whole
patio table to fall down and break the tabletop glass.
[0005] No matter the patio tabletop glass is broken by any
aforesaid reason or other unexpected reasons, the glass is broken
into particles and/or pieces with sharp edges that may cause
serious body injury to the users, especially to the minors.
However, no glass is unbreakable. Thus, the applicant of the
present invention seeks a different way to resolve the above
problem, i.e. to prevent the broken glass pieces and particles from
breaking apart.
SUMMARY OF THE PRESENT INVENTION
[0006] It is thus a first object of the present invention to
provide a patio tabletop glass with broken protection, wherein even
when the patio tabletop glass is broken into pieces and p articles,
the broken glass pieces and particles will not breaking apart and
remain attaching to a protection layer.
[0007] A further object of the present invention is to provide a
patio tabletop glass which is fast and inexpensive adapted for mass
production.
[0008] Another object of the present invention is to provide a
patio tabletop glass with broken protection, which provides a
central hole on a protection layer after it is firmly adhered on a
tempered glass layer without causing an elongated bubble popping up
between the tempered glass layer and the protective layer and
extending from the edge of the central hole to the peripheral edge
of the tabletop glass.
[0009] Another object of the present invention is to provide a
patio tabletop glass with broken protection, wherein the round edge
of the center hole of the protection layer is made to form a
protective edge extended around the central hole of the tempered
glass layer which is the most weakened area because of the high
concentrate stress occurred around the central hole.
[0010] Accordingly, in order to accomplish the above objects, the
present invention provides a patio tabletop glass with broken
protection, which comprises a tempered glass layer having a
predetermined shape and size, a protection layer made of polyvinyl
chloride or polyester sheet having a thickness of 0.3 to 0.8 mm and
a shape and size adapted to cover a top surface of the tempered
glass layer, and an adhesive layer which has a preferred thickness
between 0.1 to 0.2 mm and is made of acrylic adhesive and the like
being evenly applied between the top surface of the tempered glass
layer and a bottom surface of the protection layer so as to
integrally adhere the protection layer with the tempered glass
layer to form an one piece body, wherein the patio tabletop glass
is manufactured by the steps of:
[0011] (a) fully cleaning at least the top surface of the tempered
glass layer which has a central hole thereon with neutral water
having a pH of 7 so as to remove any possible oil thereon;
[0012] (b) drying the cleaned tempered glass layer;
[0013] (c) heating the entire tempered glass layer to a temperature
between 45.degree. C. to 65.degree. C.;
[0014] (d) evenly applying a kind of acrylic adhesive on the top
surface of the tempered glass layer which temperature is maintained
between 45.degree. C. to 65.degree. C. to form the adhesive
layer;
[0015] (e) attaching the protection layer having a thickness of 0.3
to 0.8 mm and a width size larger than the tempered glass layer on
top of the adhesive layer of the tempered glass layer by pressing
the protection layer against the top surface of the tempered glass
layer which is maintained at the temperature of 45.degree. C. to
65.degree. C. until the protection layer is integrally attached on
the tempered glass layer, wherein the protection layer has a
circular center portion formed above the central hole of the
tempered glass layer;
[0016] (f) cutting excessive edges of the protection layer to a
size identical to the tempered glass layer; and
[0017] (g) forming a center hole on the protection layer, which
coaxially aligns with the central hole of the tempered glass
layer.
BRIEF DESCRIPTION OF THE DRAWINGS
[0018] FIG. 1 is a sectional view of the patio tabletop glass in
accordance with the above preferred embodiment of the present
invention.
[0019] FIG. 2 is a flow diagram of a manufacturing process for
producing a patio tabletop glass in accordance with a preferred
embodiment of the present invention.
[0020] FIG. 3 is a perspective view illustrating the cutting step
in accordance with the above preferred embodiment of the present
invention.
[0021] FIG. 4 is a sectional view illustrating how the protection
layer is ensured to perfectly stick on the tempered glass layer in
accordance with the above preferred embodiment.
[0022] FIG. 5 is a flow diagram of a process of forming the center
hole on the protection layer in accordance with the above preferred
embodiment of the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0023] Referring to FIGS. 1 and 2, a preferred embodiment of the
present invention is illustrated. As shown in FIG. 2, a patio
tabletop glass 10 of the present invention comprises a tempered
glass layer 11, a protection layer 12 and an adhesive layer 13. The
tempered glass layer 11 has a predetermined shape, thickness and
width size and a central hole 111 provided thereon. The protection
layer 12 is made of polyvinyl chloride or polyester sheet having a
thickness of 0.3 to 0.8 mm and a shape and width size identical to
that of the tempered glass layer 11.
[0024] The tempered glass layer 11 is generally made of figured
glass that has an uneven top surface 112 having specific decorative
pattern. The protection layer 12 is integrally attached on the top
surface 112 of the tempered glass layer 11 and has a center hole
121 formed thereon, wherein the center hole 121 of the protection
layer 12 has an identical diameter of the central hole 111 and is
coaxially aligned with the central hole 111 of the tempered glass
layer 11. The adhesive layer, which has a preferred thickness
between 0.1 to 0.2 mm and is made of acrylic adhesive and the like,
is evenly applied between the top surface 112 of the tempered glass
layer 11 and a bottom surface 122 of the protection layer 12 so as
to integrally adhere the protection layer 12 with the tempered
glass layer 11 to form an one piece body. Moreover, the tension of
a periphery portion 123 of the protection layer 12 is increased to
form a protective edge 124, i.e. the round edge of the center hole
121, which is made to extend around the central hole of the
tempered glass layer which is the most weakened area because of the
high concentrate stress occurred around the central hole, and to
ensure the periphery portion 123 of the protection layer 12 around
the center hole 121 securely attached around the central hole 111
on the tempered glass layer 11.
[0025] For mass production, as shown in FIGS. 1 to 5, the structure
of patio tabletop glass 10 as described above can be made according
to the following steps:
[0026] (a) Provide a plurality of the tempered glass layers 11 each
having the predetermined shape and width size as well as the
central hole 111 provided thereon.
[0027] The step (a) further comprises the steps of cutting large
piece of glass board to form a circular shaped glass layer having
the specific decorative pattern provided on at least the top
surface 112, drilling the central hole 111 on the glass layer and
tempering the glass layer by heating the glass layer to about
500.degree. C.-550.degree. C. and then immediately cooling down to
0.degree. C.-40.degree. C. to form the tempered glass layer 11.
[0028] (b) Fully clean at least the top surface 112 of each of the
tempered glass layers 11 with neutral water having a pH of 7 so as
to remove any possible oil thereon.
[0029] (c) Dry all cleaned tempered glass layers 11.
[0030] (d) Heat each of the tempered glass layers 11 entirely to a
temperature between 45.degree. C. to 65.degree. C.
[0031] (e) Attach the protection layer 12 having a thickness of 0.3
to 0.8 mm and a width size larger than the tempered glass layer 11
on the top of the adhesive layer 13 of the tempered glass layer 11
by pressing the protection layer 12 against the top surface 112 of
the tempered glass layer 11 which is maintained at the temperature
of 45.degree. C. to 65.degree. C. until the protection layer 12 is
integrally attached on the tempered glass layer 11, wherein the
protection layer 11 has a circular center portion 120 formed above
the central hole 111 of the tempered glass layer 11.
[0032] As shown in FIG. 2, the step (e) further comprises the
following steps:
[0033] (e-1) Evenly apply a layer of acrylic adhesive or the like
on the top surface 112 of each of the tempered glass layers 11
which temperature is maintained between 45.degree. C. to 65.degree.
C. to form the adhesive layer 13 having the thickness of 0.1 to 0.2
mm.
[0034] (e-2) Provide a roll of continuous protection layer 12'
having the thickness of 0.3 to 0.8 mm and a width size larger than
that of the tempered glass layers 11.
[0035] The bottom surface of the continuous protection layer 12'
may also provided with a layer of acrylic adhesive or the like to
facilitate the continuous protection layer 12' to adhere to the
tempered glass layers 11.
[0036] (e-3) Feed one end of the protection layer 12' and the
plurality of tempered glass layers 11 one after one between a pair
of parallel rubber rollers 21, 22, wherein the continuous
protection layer 12' is attached on the top of the adhesive layers
13 of the tempered glass layers 11 in overlapped manner. The pair
of parallel rubber rollers 21, 22 are arranged to press the
continuous protection layer 12' against the top surfaces 111 of the
tempered glass layers 11, which are still maintained at the
temperature of 45.degree. C. to 65.degree. C., until the continuous
protection layer 12' is integrally adhered on the top surface 112
of each of the tempered glass layers 11.
[0037] (e-4) As shown in FIG. 3, cut off the continuous protection
layer 12' according to the number of the tempered glass layers 11
into a plurality of the protection layers 12.
[0038] (f) As shown in FIG. 3. cut away the excessive edges of each
of the protection layers 12 to a size identical to the respective
tempered glass layer 11.
[0039] (g) As shown in FIGS. 2 and 3, form the center hole 121 on
each of the protection layers 12 to coaxially align with the
central hole 112 of the respective tempered glass layer 11 to form
the patio tabletop glass 10.
[0040] According to the present invention, the step (g) further
comprises the steps of:
[0041] (g-1) pressing the center portion 120 of the protection
layer 12 toward the central hole 111 of the tempered glass layer 11
that increases the tension of a peripheral portion 123 of the
protection layer 12 attached around the central hole 111 of the
tempered glass layer 11 to ensure the peripheral portion 123 of the
protection layer 12 extending and attaching to an upper edge of the
central hole 111 of the tempered glass layer 11; and
[0042] (g-2) grinding the upper edge of the central hole 111 of the
tempered glass layer 11 until the center portion 120 of the
protection layer 12 is separated from the protection layer 12 to
form a center hole 121 coaxially aligned with the central hole 111
of the tempered glass layer 11.
[0043] The step (g), as shown in FIG. 5, is a specific step
designed to form the center hole 121 for the present invention. It
should be noted that the center portion 120 is not directly cut
from the protection layer 12 to form the center hole 121. It is
because if the center portion 120 is directly cut out from the
protection layer 12, the peripheral edge of the center hole 121
will not be fittedly attached to the upper edge of the central hole
111, so that further grinding step may be required to remove the
cutting edge of the center hole 121. Moreover, to directly cut out
the center portion 120 from the protection layer 12 will frequently
cause an elongated bubble popping up between the tempered glass
layer 11 and the protective layer 12 and extending from the edge of
the central hole to the peripheral edge of the tabletop glass.
[0044] According to the present invention, no cutting is required
to form the center hole 121, wherein in the step (g-1), as shown in
FIG. 5, a press mold 20, which has a round shaped presser head 21
at one end thereof, is used to coaxially press against the center
portion 120 by pressing into the center portion 120 into the
central hole 111 of the tempered glass layer 11. The inward
pressing force of the pressing head 21 increases the tension of the
peripheral portion 123 of the protection layer 12. Also, since the
bottom surface 122 of the protection layer 12 may also provided
with adhesive layer, the inward pressing force of the pressing head
21 will further press the peripheral portion 123 of the protection
layer 12 to extend and attach to the upper edge of the central hole
111 of the tempered glass layer 11.
[0045] Then, in the step (g-2), a rotating sand wheel is used to
grind at the position of the corresponding upper edge of the
central hole 111 so as to reduce the thickness of the peripheral
edge of the center portion 120 until the center portion 120 of the
protection layer 12 is separated from the protection layer 12 to
form a center hole 121 coaxially aligned with the central hole 111
of the tempered glass layer 11. To form the center hole 121 by the
pressing and grinding steps in step (g) can, at the same time,
substantially eliminate uneven adhering tension of the protection
layer 12 to prevent the elongated bubbles popping up between the
tempered glass layer 11 and the protective layer 12.
[0046] Alternatively, since the protection layer 12 is a thin film
and most of the tempered glass layers 11 to be used to make the
patio tabletop glass contain decorative patterns on the surfaces,
as shown in FIG. 4, in order to ensure the protection layer 12
being completely attached on the tempered glass layer 11 under even
tension, the step (e-3) can be modified to used a pair of hard
rollers 21", 22" to substitute the pair of rubber rollers 21, 22.
However, a pressure board 30, such as a cardboard or a soft pad
made of foam or rubber material having a thickness of about 2 mm,
should be placed on top of the protection layer 12 before feeding
between the pair of hard rollers 21", 22", wherein the pressure
board 30 can not only protect the protection layer 12 but also
transfer the greater pressing force applied by the hard rollers
21", 22" to even pressure for attaching the protection layer 12 on
the tempered glass layer 11.
[0047] In view of above, when the patio tabletop glass 10 is broken
into pieces and particles, the top surfaces of each of the broken
glass pieces and particles will still be individually attached to
the protection layer 12 so as to prevent the broken glass pieces
and particles from breaking apart and falling down. In other words,
the present invention provides an effective way to solve the
conventional glass breaking problem. Moreover, the manufacturing
process of the patio tabletop glass is fast and inexpensive adapted
for mass production.
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