Oil reservoir for oil burner

An oil reservoir for an oil burner capable of ensuring oil-tightness between the oil reservoir and a partition with simple operation and structure and reducing a manufacturing cost. In the oil reservoir, a partition plate and a cover plate are provided with a plurality of spot welding portions and opposite to each other through an annular overlap formed therebetween. One of the partition plate and cover plate is formed at the overlap with an annular projection which is arranged in a manner to project toward the other to forcedly press the partition plate and cover plate against each other and the overlap is arranged at or near the spot welding portions, whereby the partition plate and cover plate are oil-tightly connected together.

BACKGROUND OF THE INVENTION 
1. Field of the Invention 
This invention relates to an oil reservoir for an oil burner, and more 
particularly to an improvement in an oil reservoir of the double structure 
type for an oil burner. 
2. Description of the Prior Art 
Conventionally, an oil reservoir for an oil burner is generally constructed 
into a double structure so that leakage of fuel oil from the reservoir may 
be effectively prevented when the oil burner falls down sideways, as 
disclosed in Japanese Utility Model Publication No. 29568/1976. More 
particularly, the conventional oil reservoir is divided into an oil 
storing chamber and a wick receiving chamber by means of a partition. The 
partition airtightly isolates the oil storing chamber and the wick 
receiving chamber from each other. Fuel oil stored in the oil storing 
chamber is supplied little by little through a communication hole of the 
partition to the wick receiving chamber. 
In the conventional oil reservoir constructed as described above, a failure 
in airtight connection between the partition and the oil reservoir causes 
air to pass through a connection therebetween, resulting in failing to 
prevent the above-described leakage of fuel oil from the oil reservoir. In 
order to avoid such a problem, the partition and oil reservoir are 
connected by seam welding for ensuring airtight connection therebetween. 
However, seam welding requires large-scaled facilities and is highly 
troublesome in operation. Also, it causes workability to be deteriorated. 
Thus, it tends to produce many deficiencies in the oil reservoir. 
In view of the foregoing, the assignee proposed to accomplish airtightness 
between the partition and the oil reservoir using a rubber packing as 
disclosed in Japanese Utility Model application No. 86463/1982 (Japanese 
Utility Model application Laying-Open Publication No. 188504/1983). 
Unfortunately, the approach incurs an increase in the number of parts 
used, resulting in failing a decrease in manufacturing cost. 
Accordingly, it would be highly desirable to develop an oil reservoir for 
an oil burner which is capable of ensuring oil-tightness between the oil 
reservoir and a partition with simple operation and structure and reducing 
a manufacturing cost. 
SUMMARY OF THE INVENTION 
Generally speaking, an oil reservoir for an oil burner is provided. The oil 
reservoir includes a cover plate having a round outer end and a bottom 
plate having a round outer end and sealedly connected to a bottom of the 
cover plate to form a housing in which a closed space is defined. In a 
preferred embodiment, the cover plate and bottom plate each are formed 
into an annular shape. The oil reservoir also includes an annular 
partition plate arranged in the housing and connected at an upper end 
thereof to the cover plate and at a lower end thereof to the bottom plate 
to divide the closed space into an oil storing chamber and a wick 
receiving chamber. The partition plate is formed with at least one 
communication hole for ensuring fluid-communication between the oil 
storing chamber and the wick receiving chamber. In a preferred embodiment, 
two such communication holes are provided in a manner to be vertically 
spaced from each other. The partition plate and cover plate are provided 
with a plurality of spot welding portions at which spot welding is carried 
out to fix the partition plate and cover plate together to ensure 
oil-tightness between both. In the spot welding portions may be arranged 
in a circumferential direction of the oil reservoir. The partition plate 
and cover plate are opposite to each other through an annular overlap 
formed therebetween and one of the partition plate and cover plate is 
formed with an annular projection at the overlap. The projection is 
arranged in a manner to project toward the other of the partition plate 
and cover plate to forcedly press the partition plate and cover plate 
against each other. The overlap being arranged at or near he spot welding 
portions. 
Accordingly, it is an object of the present invention to provide an oil 
reservoir for an oil burner which is capable of effectively preventing 
leakage of fuel oil therefrom. 
It is another object of the present invention to provide an oil reservoir 
for an oil burner which is capable of accomplishing oil-tightness between 
a cover plate and a partition plate with a simple structure. 
It is another object of the present invention to provide an oil reservoir 
for an oil burner which is capable of decreasing the number of parts. 
It is a further object of the present invention to provide an oil reservoir 
for an oil burner which is capable of decreasing its manufacturing cost. 
It is still another object of the present invention to provide an oil 
reservoir for an oil burner which is capable of significantly improving 
workability. 
Still other objects and advantages of the invention will in part be obvious 
and will in part be apparent from the specification. 
The invention accordingly comprises the features of construction, 
combination of elements, and arrangement of parts which will be 
exemplified in the construction hereinafter set forth, and the scope of 
the invention will be indicated in the claims.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
Now, an oil reservoir for an oil burner according to the present invention 
will be described hereinafter with reference to the accompanying drawings. 
FIG. 1 shows an example of an oil burner which is adapted to incorporate an 
oil reservoir according to the present invention therein, wherein an oil 
burner and an oil reservoir are generally designated by reference numerals 
10 and 12, respectively. The oil burner 10 takes the form of a space 
heater, however, it should be noted that an oil burner to which an oil 
reservoir of the present invention is applied is not limited to a space 
heater. 
The oil burner 10 illustrated in FIG. 1 is constructed in such a manner as 
widely known in the art, except the oil reservoir 12 of the present 
invention. The oil burner 10 includes a wick receiving cylinder 
construction 14 arranged on the oil reservoir 12. The wick receiving 
cylinder construction 14 is adapted to receive a wick 16 therein and 
communicated with the oil reservoir 12. The oil burner 10 also includes a 
combustion cylinder construction 18 arranged on the wick receiving 
cylinder 14. 
The combustion cylinder construction 18 includes a double combustion 
cylinder 20 consisting of an inner cylindrical member 22 and an outer 
cylindrical member 24 which are arranged in a manner to be substantially 
concentric with each other through a space 26 of a suitable interval 
defined therebetween. The inner cylindrical member 22 is formed with a 
plurality of through-holes 28 which serve to introduce combustion air 
therethrough to the space 26 from an internal cylindrical space 30 formed 
in the oil burner 10 and communicated through a bottom of the burner with 
an ambient atmosphere. Likewise, the outer cylindrical member 24 is formed 
with a plurality of through-holes 32. The combustion cylinder construction 
18 further includes a heat-permeable cylinder 34 supported through a 
support cylinder 36 on the wick receiving cylinder construction 14. On the 
combustion cylinder construction 18 are arranged a coil 38 formed of metal 
and a top plate 40. 
The oil burner 10 further includes a wick actuating mechanism arranged at 
the wick receiving cylinder construction 14 and generally indicated at 
reference numeral 42, which is also constructed in a manner widely known 
in the art. The mechanism 42 includes a wick drive shaft 44 having a knob 
46 and a pinion 48 respectively mounted at outer and inner ends thereof 
and a wick moving plate 50 having a rack 52 mounted on an outer surface 
side thereof. The wick 16 is held on an inner surface of the wick moving 
plate 50. The rack 52 is engaged with the pinion 48, so that the plate 50 
may be vertically moved while being rotated through engagement between the 
pinion 48 and rack 52 when the drive shaft 44 is rotated, resulting in the 
wick 16 being vertically moved along a central base cylinder 54 of the oil 
burner 10 in which the space 30 is defined. 
The oil reservoir 12 of the illustrated embodiment is shown in FIGS. 1 to 
3. FIG. 2 enlargedly shows the oil reservoir 12, from which the wick 
actuating mechanism 42 is substantially deleted for the sake of brevity. 
The oil reservoir 12 which is adapted to store fuel oil such as kerosene or 
the like therein is generally formed into an annular shape and arranged 
around the central base cylinder 54 so as to oil-tightly surround the 
cylinder 54. The oil reservoir 12 includes a cover plate 56 having a round 
outer end surface and a bottom plate 58 having a round outer end and 
oil-tightly mounted in the cover plate 56 to form a housing. In the 
illustrated embodiment, the cover plate 56 and bottom plate 58 are formed 
into an annular shape, so that an annular space 60 is defined in the 
housing. Also, in the illustrated embodiment, the cover plate 56 is formed 
so as to constitute upper and side walls of the housing of the oil 
reservoir 12 and the bottom plate constitutes a bottom wall of the 
housing. The oil reservoir 12 may be constructed by welding the housing 
constituted by the cover and bottom plates 56 and 58 to the central base 
cylinder 54 of the oil burner 10. The oil reservoir 12 also includes a 
partition plate 62 of an annular shape interposedly arranged between the 
cover plate 56 and the bottom plate 58 in the housing, so that the annular 
space 60 in the oil reservoir is divided into an oil storing chamber 64 
and a wick receiving chamber 66, which are communicated through at least 
one communication hole 68 formed at the partition plate 62 with each 
other. In the illustrated embodiment, two such communication holes 68 are 
formed in a manner to be vertically spaced from each other. The 
communication holes 68 serve to ensure fluid-communication between the oil 
storing chamber 64 and the wick receiving chamber 66. 
In the illustrated embodiment, oil-tight fixing of the partition plate 62 
to the cover plate 56 is carried out through a ring-like or annular 
overlap 70 of a certain or relatively large width formed between the 
partition plate 62 and the cover plate 56. One of the cover plate 56 and 
partition plate 62 is formed with a ring-like or annular projection 72 at 
the overlap 70 in a manner to be opposite to the other of the cover plate 
56 and partition plate 62, so that the cover plate 56 and partition plate 
62 may be forcedly or elastically abutted against each other by means of 
the projection 72. The projection 72 is arranged along a whole 
circumference of the overlap 6, resulting in being formed into a annular 
or ring-like shape. The cover plate 56 and partition plate 62 are fixed 
together at or near the overlap 70 by spot-welding a plurality of spot 
welding portions 74 provided at both plates so as to prevent one of them 
from being separated from the other. The spot welding portions may be 
arranged so as to be spaced at equal intervals from one another in a 
circumferential direction of the oil reservoir. 
A whole configuration of the overlap 72 between the cover plate 56 and the 
partition plate 62 is substantially cylindrical when it is formed between 
vertical portions of the cover plate 56 and partition plate 62 as shown in 
FIGS. 2 and 3; whereas it is in the form of a flat doughnut-like shape 
when the overlap 72 is formed between horizontal or substantially 
horizontal portions of both. 
When the overlap 70 is formed between the vertical portions of the cover 
plate 56 and partition plate 62 or into a cylindrical shape as shown in 
FIGS. 2 and 3, it is preferable that a maximum outer diameter D1 of the 
partition plate 62 at the overlap 70 is defined to be larger than an inner 
diameter D2 of the cover plate 56 at the overlap. In FIG. 2, the 
projection 72 is provided for this purpose, which is formed by 
circumferentially outwardly projecting a part of the vertical portion of 
the partition plate 62. When the partition plate 62 provided with the 
so-formed projection 72 is fitted in the cover plate 56, the projection 72 
is forcedly abutted against an inner surface of the cover plate 56 to 
securely hold the partition plate 62 in the cover plate 56. 
When the overlap 70 is formed between the horizontal or substantially 
horizontal portions of the cover plate 56 and partition plate 62 or into a 
flat doughnut-like shape as shown in FIGS. 4C and 4D described 
hereinafter, the projection 72 acts to force the overlapped portions of 
both plates against each other to ensure secure engagement therebetween 
when spot welding is carried out. 
FIGS. 4A to 4D each show a form of the projection 72 and a relationship 
between the projection 72 and the overlap 70, wherein a mark "x" indicates 
a position of spot welding. In FIG. 4A, a circumferential or annular 
projection 72 is formed by outwardly turning up a tip end of a vertical 
upper portion of the partition plate 62 forming a cylindrical overlap 70 
in cooperation with the cover plate 56 so that a maximum outer diameter of 
the partition plate 62 may be larger than an inner diameter of the cover 
plate and spot welding 74 is carried out at the overlap 70. In FIG. 4B, a 
circumferential or annular projection 72 is formed by outwardly turning up 
an upper portion of the partition plate 62 and then outwardly projecting a 
tip end of the upper portion. The turned-up upper portion of the partition 
plate 62 forms a cylindrical overlap 70 in cooperation with a vertical 
portion of the cover plate 56. Spot welding 74 is carried out adjacent to 
the overlap 70. In FIG. 4C, a flat doughnut-like overlap 70 is formed and 
spot welding 74 and a projection 72 are formed at the overlap 70. Also, 
the projection 72 is formed at the partition plate 62. FIG. 4D is 
substantially the same as FIG. 4C except that a projection 72 is formed at 
the cover plate 56. 
In the oil reservoir 12 of the illustrated embodiment, when the cover plate 
56 and partition plate 62 are fixed together by spot welding 74 as 
described above, the annular projection 72 formed at one of the cover 
plate 56 and partition plate 62 is forcedly pressed against the other, 
resulting in both being sealedly or intimately contacted together and 
securely engaged together at the projection 72. Also, any gap possibly 
formed between the cover plate 56 and the partition plate 62 due to the 
projection 72 is eliminated by spot welding, so that fluid-tightness of 
the overlap 70 may be effectively ensured. 
As can be seen from the foregoing, in the oil reservoir of the present 
invention, the overlap of a relatively large width is formed between the 
cover plate and the partition plate and provided with the projection which 
serves to ensure secure engagement between both plates and forcedly press 
both plates against each other to enhance fluid-tightness therebetween. 
Also, fixing between both plates which further promotes fluid-tightness 
therebetween is readily accomplished by spot welding other than seam 
welding. Thus, it will be noted that the oil reservoir of the present 
invention significantly improves workability, decreases in the number of 
parts used and reduces manufacturing costs. 
It will thus be seen that the objects set forth above, among those made 
apparent from the preceding description, are efficiently attained and, 
since certain changes may be made in the above construction without 
departing from the spirit and scope of the invention, it is intended that 
all matter contained in the above description or shown in the accompanying 
drawings shall be interpreted as illustrative and not in a limiting sense. 
It is also to be understood that the following claims are intended to cover 
all the generic and specific features of the invention herein described 
and all statements of the scope of the invention which, as a matter of 
language, might be said to fall therebetween.