[0001] This invention relates to a condenser for use in a refrigerant circuit of an automotive
air-conditioning system and, in particular, to a condenser with a built-in receiver
for temporarily accumulating a refrigerant condensed to a liquid state.
[0002] A conventional condenser with a built-in receiver of the type is disclosed, for example,
in United States Patent No. 5,088,294. The condenser comprises an inlet header pipe
connected to an inlet pipe for introducing a refrigerant, an outlet header pipe connected
to an outlet pipe for discharging the refrigerant, a plurality of flat heat exchange
tubes disposed in parallel to one another between the inlet and the outlet header
pipes and inserted in and connected to the inlet and the outlet header pipes, and
a plurality of corrugated fins arranged between every adjacent ones of the heat exchange
tubes.
[0003] In the above-mentioned condenser, the outlet header pipe is provided with a receiver
for temporarily accumulating a refrigerant condensed to a liquid state to conduct
the liquid refrigerant to the outlet pipe. Generally, the receiver is prepared as
a separate element and is fixedly attached to the outlet header pipe. Specifically,
the heat exchange tubes are inserted into axially arranged holes in a side of a pipe
wall of the outlet header pipe in a tube inserting direction and sealed and fixed
to the pipe wall. The receiver is attached to the opposite side surface of the outlet
header pipe in a direction opposite to the tube inserting direction.
[0004] In an assembling process of the condenser with such a built-in receiver, a partition
plate is arranged in each of the header pipes to define the flow path of the refrigerant
to and from the heat exchange tubes. Generally, the partition plate is inserted into
the header pipe at the side opposite to the heat exchange tubes in a partition inserting
direction opposite to the tube inserting direction. As for the outlet header pipe,
the receiver is located at the partition plate insertion side, that is, in the partition
inserting direction. Therefore, in the assembling process of the condenser, the partition
plate is inserted into and bonded to the outlet header pipe before the receiver is
attached to the outlet header pipe. Thus, the assembling process is complicated.
[0005] Alternatively, it is assumed that the partition plate is inserted into the header
pipe at the same side as the exchange tubes, that is, in the partition inserting direction
which is coincident with the tube inserting direction in order to simplify the assembling
process. In this case, in a preparation process of header pipes, a partition insertion
slot for inserting the partition plate and tube insertion slots for inserting the
heat exchange tubes are punched in the outlet header pipe at the same side in the
same direction. As a result, the partition insertion slot is formed in the close vicinity
of the tube insertion slots. Therefore, it is very difficult to perform the punching
operation insuring sufficient mechanical strength and the correct shape of each slot.
[0006] In the above-mentioned structure in which the receiver is disposed to the header
pipe at the opposite side of the heat exchange tubes in the tube inserting direction,
a size of the condenser in the tube inserting direction is increased by a width of
the receiver so that the heat exchanging area of the condenser is reduced when a space
for installing the condenser is limited.
[0007] It is therefore an object of this invention to provide a REFRIGERANT condenser with
a built-in receiver, which enables a partition plate to be easily arranged in an outlet
header pipe without degradation in machinability of insertion slots and in mechanical
strength, which can be easily assembled, and which can avoid reduction of an effective
heat exchange area.
[0008] This invention is applicable to a refrigerant condenser with a built-in receiver
including an outlet header pipe, a plurality of heat exchange tubes connected to the
outlet header pipe through a side wall thereof, the outlet header pipe having therein
one or more partition plate for controlling flow of the refrigerant to define a refrigerant
flow path, the partition plate being inserted into the outlet header pipe at an opposite
side of the heat exchange tubes in a partition inserting direction, and the receiver
being provided to the outlet header pipe for temporarily accumulating the refrigerant
condensed into a liquid state. According to this invention, the refrigerant condenser
is characterized in that the outlet header pipe is in a type of a receiver-integral
structure comprising a portion of the outer header pipe and a receiver portion integrally
formed and beinq in fluid communication with the outer header pipe portion. The receiver
portion extends from the outlet header portion in a direction perpendicular to the
partition inserting direction.
[0009] In a further aspect, the receiver-integral type header pipe has first and second
flow paths separated by an axially extending internal partition wall with a gap formed
at one end thereof. The first flow path is a liquid refrigerant flow path in the receiver
portion while the second flow path is the outlet header pipe portion and is further
separated by the partition plate into the heat exchanging flow path for the refrigerant
to and from the heat exchange tubes and an accumulating portion for the receiver portion
for accumulating the refrigerant in a liquid state.
[0010] Preferably, the receiver-integral type header pipe having the first and the second
flow paths is formed by an extruded blank pipe having two axial cavities.
[0011] In a further aspect, the receiver portion is connected with an outlet pipe outwardly
extending from the receiver portion in a direction perpendicular to the partition
inserting direction for conducting the liquid refrigerant to an exterior.
[0012] In the accompanying drawings:-
Fig. 1 is a side sectional view of a characteristic part of a conventional condenser
with a built-in receiver;
Fig. 2 is a front view of a condenser with a built-in receiver according to one embodiment
of this invention;
Fig. 3 is a plan view of the condenser illustrated in Fig. 2;
Fig. 4 is a vertical sectional view of a receiver-integral header pipe of the condenser
illustrated in Fig. 3, taken along a line IV-IV;
Fig. 5 is a perspective view of the header pipe illustrated in Fig. 4; and
Fig. 6 is an enlarged perspective view of the header pipe illustrated in Fig. 4 with
a part cut away.
[0013] In order to facilitate an understanding of this invention, description will at first
be made about a conventional condenser with a built-in receiver.
[0014] Referring to Fig. 1, the conventional condenser with a built-in receiver comprises
a plurality of heat exchange tubes 101 (only one being shown in Fig. 1) which are
inserted into axially arranged holes in a side of a pipe wall of an outlet header
pipe 102 in a tube inserting direction and connected to the outlet header pipe 102.
A receiver 103 is fixedly attached to the outlet header pipe 102 at the opposite side
in a direction opposite to the tube inserting direction.
[0015] The above-mentioned structure, however, results in various problems in an assembling
process of the condenser or a machining process of parts. Specifically, in the assembling
process, at least one partition plate 100 is arranged in the outlet header pipe 102.
Generally, the partition plate 100 is inserted into the outlet header pipe 102 in
a direction depicted at A in the figure. However, the receiver 103 is located forward
in the direction A. In presence of the receiver 103, it is quite difficult to insert
the partition plate 100. Under the circumstances, in the assembling process, the partition
plate 100 is inserted into and bonded to the outlet header pipe 102 before the receiver
103 is attached to the outlet header pipe 102. Thus, the assembling process is complicated.
[0016] Alternatively, it is assumed that the partition plate 100 is oppositely inserted
into the outlet header pipe 102 that is, in the direction same as the tube inserting
direction in order to simplify the assembling process. In this case, in the machining
process, a partition insertion slot for inserting the partition plate 100 and tube
insertion holes for inserting the heat exchange tubes 101 are both punched in the
pipe wall of the outlet header pipe 102 at the same side in the same direction. As
a result, the partition insertion slot is formed in the close vicinity of the tube
insertion holes. Therefore, it is very difficult to perform the punching operation
insuring sufficient mechanical strength and the correct shape of each slot.
[0017] Taking the above into consideration, it is proposed to form the partition insertion
slot in the outlet header pipe 102 at a different position angularly offset from the
tube inserting direction and also apart from the location of the receiver 103. For
example, the partition insertion slot is formed in the pipe wall of the outlet header
pipe 102 at a position in a direction B perpendicular to the tube inserting direction
A. Then, the partition plate 100 is inserted into the outlet header pipe 102 in the
direction B. In this event, the tube insertion holes and the partition insertion slot
are formed in the pipe wall of the outlet header pipe 102 in an orthogonal relationship.
Such structure results in difficulty in punching operation and degradation in mechanical
strength.
[0018] More specifically, if the tube insertion holes and the partition insertion slot are
formed in the pipe wall of the outlet header pipe 102 in the orthogonal relationship,
those slot and holes are too close to each other. In this event, it is difficult to
avoid serious degradation in mechanical strength. In addition, mutual interference
in punching operation deteriorates dimensional accuracy of the slot and holes. This
results in difficulty in subsequent insertion and assembling of the heat exchange
tubes 101 and the partition plate 100 to the outlet header pipe 102. Therefore, the
method of punching out the slot and holes in the orthogonal relationship is not adopted
because of the above-mentioned disadvantages. As traditionally, the tube insertion
holes and the partition insertion slot are formed at positions angularly spaced by
180° to each other in the manner described above.
[0019] In the above-mentioned condenser with the built-in receiver, the receiver 103 is
disposed at the opposite position of the outlet header pipe 102 to the heat exchange
tubes 102 in the tube inserting direction. Therefore, a size of the refrigerant condenser
increases in the tube inserting direction by the width of the receiver. This means
that when the space for installing the condenser is limited, the efficient heat exchange
area is reduced by presence of the receiver.
[0020] Under the circumstances, it is desired to achieve an improved condenser with a built-in
receiver which enables a partition plate to be easily inserted into the outlet pipe
in an ordinary direction or at the side opposite to the heat exchange tubes without
degradation in machinability of insertion slots and in mechanical strength, which
can be easily assembled, and which can avoid reduction of an effective heat exchange
area.
[0021] Referring to Fig. 2, a condenser 1 with a built-in receiver according to an embodiment
of this invention is basically similar in structure to the conventional condenser
described in the foregoing. Specifically, the condenser 1 comprises an inlet header
pipe 2 connected to an inlet pipe 8 for introducing a refrigerant, an outlet header
pipe 3 connected to an outlet pipe 9 for discharging the refrigerant, a plurality
of flat heat exchange tubes 4 disposed in parallel to one another between the inlet
header pipe 2 and the outlet header pipe 3 and inserted in and connected to the inlet
and the outlet header pipes, a pair of reinforcing plates 6 arranged at opposite sides
of an array of the heat exchange tubes 4, and a plurality of corrugated fins arranged
between every adjacent ones of the heat exchange tubes 4 and between the heat exchange
tubes 4 and the reinforcing plates 6.
[0022] The condenser 1 is of a so-called multiflow type. A partition plate 10 is inserted
into and bonded to the inlet header pipe 2. Likewise, a partition plate 11 is inserted
into and bonded to the outlet header pipe 3. These partition plates 10 and 11 are
for defining the flow path of the refrigerant to and from the heat exchange tubes
4. Herein, the outlet header pipe 3 is a portion of a receiver-integral type header
pipc 7 which has also a receiver portion 13 integrally formed with and being in fluid
communication with the outlet header pipe portion 3.
[0023] In the receiver-integral type header pipe 7, the receiver portion 13 generally extends
from the outlet header pipe portion 3 in a direction B perpendicular to a partition
inserting direction A, as illustrated in Fig. 3. The outlet pipe 9 for conducting
the liquid refrigerant to the exterior extends continuously from the receiver portion
13 in a direction shown at C perpendicular to the partition inserting direction. The
inlet pipe 8 and the outlet pipe 9 are jointed to and communicate with the inlet header
pipe 2 and the outlet header pipe 3 illustrated in Figs. 2 and 3, respectively. Those
inlet and outlet pipes can be formed integrally with the corresponding header pipes
as single bodies, respectively.
[0024] In the receiver-integral type header pipe 7, the outlet header pipe portion 3 is
provided with tube insertion holes 12 for inserting the heat exchange tubes 4 at a
side opposite to the partition plate insertion slot, as illustrated in Figs. 3, 4
and 5.
[0025] In more detail, the receiver-integral type header pipe 7 has first and second axially-extending
flow paths separated by an internal partition wall 16 with a gap 17 formed at one
end thereof, generally providing the receiver portion 13 and the outlet header pipe
3, respectively. More specifically, the first flow path shown at 14 generally serves
as a portion for guiding the liquid refrigerant in the receiver portion 13 to the
outlet pipe 9. The second flow path is further separated by the radially-extending
partition plate 11 into an upper heat exchanging flow path for the refrigerant to
and from the heat exchange tubes 4 and a lower portion which is also connected to
the one or more heat exchange tubes 4.
[0026] The receiver-integral type header pipe 7 is closed at opposite ends by caps, a lower
one of which is shown at 18 in Fig. 6.
[0027] The lower portion of the second flow path and the lower portion of the first flow
path 14 communicate with each other through the gap 17 and serve as an accumulating
portion 15 of the receiver portion 13 for accumulating the liquid refrigerant. The
receiver-integral type header pipe 7 having the above-mentioned two flow paths is
formed as an integral element from an extruded pipe blank having two axial cavities.
[0028] Referring back to Fig. 2, the refrigerant in a gas/liquid mixed phase (in a misty
state) flows into the inlet header pipe 2 through the inlet pipe 8. The refrigerant
flows into the outlet header pipe portion 3 via one or more (two in the figure) of
the heat exchange tubes 4. As depicted by dotted lines in the figure, the refrigerant
further flows through other heat exchange tubes 4 (three in the figure) back into
the inlet header pipe 2, from which the refrigerant flows through the other heat exchange
tubes 4 (three in the figure) into the accumulating portion 15 of the receiver-integral
header pipe 7. Flowing through the heat exchange tubes 4, the refrigerant releases
heat to be cooled via the corrugated fins 5. As a result of such heat exchanging operation,
the refrigerant is condensed to a liquid state completely. The liquid refrigerant
accumulated in the accumulating portion 15 flows out from the outlet pipe 9 through
the first flow path 14.
[0029] In the receiver-integral type header pipe 7, the receiver portion 13 and the outlet
pipe 9 extend from the outlet header pipe portion 3 in the direction B perpendicular
to the tube inserting direction and the partition inserting direction A. With this
structure, in the assembling process, the partition plate 11 can be easily inserted
into the outlet header pipe portion 3 in the partition inserting direction A at the
opposite side against the heat exchange tube without any trouble.
[0030] It will be understood that the partition insertion slot can be formed in the outlet
header pipe portion 3 of the receiver-integral type header pipe 7 in the manner similar
to the ordinary punching operation in the conventional condenser shown in Fig. 1.
Through the partition insertion slot, the partition plate 11 can easily be inserted
and bonded by brazing. Although the partition insertion slot is formed in the pipe
wall of the outlet header pipe portion 3 at the side opposite to the tube insertion
holes 12, the receiver-integral type header pipe 7 has such a structure that the receiver
portion 13 is formed integral with the outlet header pipe portion extending from the
outlet header pipe 3 in the direction B perpendicular to the tube inserting direction
and the partition inserting direction and has a relatively thick side wall. Accordingly,
upon punching the tube insertion holes 12 and partition insertion slots, neither the
mechanical strength of the outlet header pipe portion 3 nor the dimensional accuracy
of the insertion holes and slot is deteriorated.
[0031] Accordingly, in the receiver-integral type header pipe 7, the partition plate 11
is easily arranged in the outlet header pipe 3 without deterioration in machinability
of the insertion slots and in mechanical strength. Therefore, the condenser 1 itself
can be easily manufactured.
[0032] In the above-described condenser 1, the receiver portion 13, the outlet header pipe
portion 3, and the outlet pipe 9 in the receiver-integral type header pipe 7 are serially
arranged in the direction C of the air flow to be heat exchanged, as seen from Fig.
3. Therefore, an effective heat exchange area of a heat exchanging region extending
in the direction perpendicular to the direction C is not reduced by presence of the
receiver 13. Although the condenser 1 of this invention has the built-in receiver,
the efficient heat exchange area is equivalent to that obtained in the condenser having
no built-in receiver.
[0033] Although the foregoing description is directed to the multiflow-type condenser 1
with the built-in receiver, the structure with the receiver-integral type header pipe
7 of this invention is applicable to various other types of condensers having built-in
receivers. The receiver-integral type header pipe 7 can be formed not only by the
extruded pipe blank with two cavities but by any other appropriate materials. For
example, use can be made of a member comprising a combination of semicylindrical pipe
members or another member having a clad structure using a brazing material.
1. A refrigerant condenser with a built-in receiver including an outlet header pipe,
a plurality of heat exchange tubes connected to said outlet header pipe through a
side wall thereof, said outlet header pipe having therein one or more partition plate
for controlling flow of the refrigerant to define a refrigerant flow path, said partition
plate being inserted into said outlet header pipe at an opposite side of said heat
exchange tubes in a partition inserting direction, and the receiver being provided
to said outlet header pipe for temporarily accumulating the refrigerant condensed
into a liquid state, wherein said outlet header pipe is in a type of a receiver-integral
structure comprising a portion of said outer header pipe and a receiver portion integrally
formed and being in fluid communication with said outer header pipe portion, said
receiver portion extending from said outlet header portion in a direction perpendicular
to said partition inserting direction.
2. A refrigerant condenser with a built-in receiver as claimed in Claim 1, wherein said
receiver-integral type header pipe has first and second flow paths separated by an
axially extending internal partition wall with a gap formed at one end thereof, said
first flow path being a liquid refrigerant flow path in said receiver portion while
said second flow path being said outlet header pipe portion and being further separated
by said partition plate into the heat exchanging flow path for the refrigerant to
and from said heat exchange tubes and an accumulating portion for said receiver portion
for accumulating said refrigerant in a liquid state.
3. A refrigerant condenser with a built-in receiver as claimed in Claim 2, wherein said
receiver-integral type header pipe having the first and the second flow paths is formed
by an extruded blank pipe having two axial cavities.
4. A refrigerant condenser with a built-in receiver as claimed in Claim 1, wherein said
receiver portion is connected with an outlet pipe outwardly extending from said receiver
portion in a direction perpendicular to said partition inserting direction for conducting
the liquid refrigerant to an exterior.