Title: Press-forming apparatus
Abstract: A press-forming apparatus comprises a pair of press-forming units detachably secured to movable and stationary units facing each other, respectively. A metallic material is subjected to a press-forming through the press-forming units and then discharged therefrom as a heat transfer member for a heat exchanger. Each of the press-forming units comprises (i) a main forming section for forming on the material a heat transfer face with a corrugated portion, (ii) a pair of first subsidiary forming sections disposed on upstream and downstream sides of the main forming section so as to be adjacent thereto in the feeding direction of the material and (iii) a forming section-support base member detachably supporting the main forming section and the first subsidiary forming sections. The main forming section has a press-forming face with main corrugation patterned portions that are symmetric with respect to a central line perpendicular to the feeding direction of the material, and boundary patterned portions, on which recesses and projections align in a direction perpendicular to the feeding direction of the material. The first subsidiary forming sections of one of the pair of press-forming units is adjustable to shift press-forming faces thereof along a pressing direction, so as to provide switchably a contact mode in which the press-forming faces come into contact with the material together with the main forming section to apply a press-forming operation to the material and a non-contact mode in which the press-forming operation is not applied thereto.
Patent Number: 6,840,080 Issued on 01/11/2005 to Matsuzaki
| Inventors:
|
Matsuzaki; Toyoaki (Shizuoka-Ken, JP)
|
| Assignee:
|
Xenesys Inc. (JP)
|
| Appl. No.:
|
387576 |
| Filed:
|
March 14, 2003 |
Foreign Application Priority Data
| Mar 18, 2002[JP] | P2002-074366 |
| Current U.S. Class: |
72/385; 72/379.6; 72/384 |
| Intern'l Class: |
B21D 013/02; B21D053/04 |
| Field of Search: |
72/385,384,404,379.6
29/890.05,727
|
References Cited [Referenced By]
U.S. Patent Documents
| 3307387 | Mar., 1967 | Lacey, Jr. et al. | 72/324.
|
| 3845654 | Nov., 1974 | Fuller et al.
| |
| 4434643 | Mar., 1984 | Almqvist et al. | 72/379.
|
| 4635462 | Jan., 1987 | Bald | 72/385.
|
| 4989440 | Feb., 1991 | Sjogren | 72/385.
|
| 5937519 | Aug., 1999 | Strand.
| |
| Foreign Patent Documents |
| 63183739 | Jul., 1988 | JP.
| |
| 05200450 | Aug., 1993 | JP.
| |
| 2001321835 | Nov., 2001 | JP.
| |
Other References
European Search Report dated May 9, 2003.
|
Primary Examiner: Crane; Daniel C.
Attorney, Agent or Firm: Kananen; Ronald P.
Rader, Fishman & Grauer PLLC
Claims
What is claimed is:
1. A press-forming apparatus comprising a pair of press-forming units,
which are detachably secured to a movable unit and a stationary unit that
face each other, respectively, so that a metallic thin sheet material to
be press-formed, which is supplied to the press-forming units in a
predetermined feeding direction, subjected to a press-forming through the
press-forming units and then discharged there from as a heat transfer
member for a heat exchanger, said heat transfer member having a
predetermined shape,
wherein:
each of said press-forming units comprises (i) a main forming section for
forming on the material to be press-formed a heat transfer face with a
corrugated portion, which has opposite surfaces to be brought into contact
with heat exchange fluids, (ii) a pair of first subsidiary forming
sections, which are each disposed on upstream and downstream sides of said
main forming section so as to be adjacent thereto in the feeding direction
of the material to be press-formed, said pair of first subsidiary forming
sections of one of said press-forming units respectively facing said pair
of first subsidiary forming sections of another of said press-forming
units to form an upstream set of first subsidiary forming sections and an
downstream set of first subsidiary forming sections in the feeding
direction of the material to be press-formed and (iii) a forming
section-support base member detachably supporting said main forming
section and said pair of first subsidiary forming sections;
said main forming section having a press-forming face on which there are
formed main corrugation patterned portions that are symmetric with respect
to a central line, which is perpendicular to the feeding direction of the
material to be press-formed, on one hand, and boundary patterned portions
having a predetermined width, on which a plurality of recesses and
projections align in a direction perpendicular to the feeding direction of
the material to be press-formed, on the other hand; and
one of said upstream set of first subsidiary forming sections and one of
said downstream set of first subsidiary forming sections being adjustable
to shift press-forming faces thereof along a pressing direction, so as to
provide switch ably a contact mode in which said press-forming faces come
into contact with the material to be press-formed together with the main
forming section to apply a press-forming operation to the material to be
press-formed and a non-contact mode in which the press-forming operation
is not applied thereto.
2. The apparatus as claimed in claim 1, wherein:
each of said pair of main forming sections has a divided structure, which
comprises a main member having on a surface thereof said main corrugated
patterned portions and a pair of end members having on a surface thereof
boundary patterned portions;
said pair of end members of one of said pair of main forming sections are
mounted on the forming section-support base member through predetermined
resilient members so as to project from a press-forming face of said main
member by a predetermined length in a state in which a pressing force is
not applied to the material to be press-formed; and
said resilient members have elasticity by which press-forming faces of said
end members are retracted to a place corresponding to the press-forming
face of the main member when a maximum pressing force is applied to the
material to be press-formed.
3. The apparatus as claimed in claim 1 or 2, further comprising:
subsidiary forming section-elevating devices having a wedge-shape, which
are disposed on the forming section-support base member on a rear side of
said pair of first subsidiary forming sections in the pressing direction,
so as to be movable in a horizontal direction, each of said subsidiary
forming section-elevating devices having on a front side in the pressing
direction an inclined surface having a predetermined inclination angle;
and
actuators for moving said subsidiary forming section-elevating devices in
the horizontal direction,
said one of said upstream set of first subsidiary forming sections and said
one of said downstream set of first subsidiary forming sections being
supported on the forming section-support base member so as to be adjusted
along the pressing direction, each of said pair of first subsidiary
forming sections being provided on an opposite surface to its
press-forming face with an inclined surface having a same inclination
angle as that of the inclined surface of said subsidiary forming
section-elevating device.
4. The apparatus as claimed in any one of claims 1 to 2, further
comprising:
a pair of second subsidiary forming sections for each of said pair of
press-forming units, said secondary subsidiary forming sections being
detachably disposed on opposite sides in a direction perpendicular to the
feeding direction of the material to be press-formed on the forming
section-support base member, so as to be adjacent to the main forming
section,
said pair of second subsidiary forming sections for one of said pair of
press-forming units being mounted on the forming section-support base
member through predetermined resilient members so as to project from the
press-forming face of said main forming section by a predetermined length
in a state in which a pressing force is not applied to the material to be
press-formed; and
said resilient members having elasticity by which press-forming faces of
said second subsidiary forming sections are retracted to a place
corresponding to the press-forming face of the main forming section when a
maximum pressing force is applied to the material to be press-formed.
5. The apparatus as claimed in any one of claims 1 to 2, further
comprising:
suction support members being disposed in positions on an upstream side of
the first subsidiary forming section on one of the forming section-support
base members in the feeding direction of the material to be press-formed,
so as to support, under a sucking operation, the material to be
press-formed, which is supplied between the forming sections while keeping
one end of the material to be press-formed in substantially the same level
as the press-forming face of said main forming section.
6. The apparatus as claimed in claim 3, further comprising:
a pair of second subsidiary forming sections for each of said pair of
press-forming units, said secondary subsidiary forming sections being
detachably disposed on opposite sides in a direction perpendicular to the
feeding direction of the material to be press-formed on the forming
section-support base member, so as to be adjacent to the main forming
section,
said pair of second subsidiary forming sections for one of said pair of
press-forming units being mounted on the forming section-support base
member through predetermined resilient members so as to project from the
press-forming face of said main forming section by a predetermined length
in a state in which a pressing force is not applied to the material to be
press-formed; and
said resilient members having elasticity by which press-forming faces of
said second subsidiary forming sections are retracted to a place
corresponding to the press-forming face of the main forming section when a
maximum pressing force is applied to the material to be press-formed.
7. The apparatus as claimed in claim 3, further comprising:
suction support members being disposed in positions on an upstream side of
the first subsidiary forming section on one of the forming section-support
base members in the feeding direction of the material to be press-formed,
so as to support, under a sucking operation, the material to be
press-formed, which is supplied between the forming sections while keeping
one end of the material to be press-formed in substantially the same level
as the press-forming face of said main forming section.
8. The apparatus as claimed in claim 4, further comprising:
suction support members being disposed in positions on an upstream side of
the first subsidiary forming section on one of the forming section-support
base members in the feeding direction of the material to be press-formed,
so as to support, under a sucking operation, the material to be
press-formed, which is supplied between the forming sections while keeping
one end of the material to be press-formed in substantially the same level
as the press-forming face of said main forming section.
9. The apparatus as claimed in claim 2, wherein said boundary patterned
portions are located in the front and rear sides in the feeding direction
of the material to be press-formed and are aligned in the perpendicular
direction to the feeding direction of said material to be press-formed.
10. The apparatus as claimed in claim 2, where said end members of said
main forming sections are disposed respectively on the opposite sides of
the main member in the feeding direction of the material to be
press-formed so as to be adjacent to the main member.
11. The apparatus as claimed in claim 2, wherein said boundary portions
have a predetermined width with patterned corrugations.
Description
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates a press-forming apparatus for subjecting a
material to a press-forming to provide a heat transfer member for a heat
exchanger, and particularly to such an apparatus which permits formation
of a plurality of press-formed portions as aligned on the material through
the press-forming steps utilizing a plurality of forming sections.
2. Description of the Related Art
If there is a wish that heat transfer coefficient is increased to enhance
heat exchange effectiveness, utilizing a heat exchanger by which heat
exchange is made between a high temperature fluid and a low temperature
fluid, a plate-type heat exchanger has conventionally been used widely.
The plate-type heat exchanger has a structure in which a plurality of heat
transfer members having a plate-shape are placed in parallel to one upon
another at prescribed intervals so as to form passages, which are
separated by means of the respective heat transfer member. A high
temperature fluid and a low temperature fluid flow alternately in the
above-mentioned passages to provide a heat exchange through the respective
heat transfer members.
In general, the heat transfer member used in the conventional plate-type
heat exchanger has a predetermined pattern of corrugations, which serves
as a heat transfer face having the opposite surfaces with which heat
exchange fluids are to come into contact. Such a pattern of corrugations
causes turbulence in the fluids to improve the heat transfer efficiency,
increases the heat transfer area and enhances the strength of the plate.
The heat transfer member having such a pattern of corrugations is generally
formed of a metallic sheet. The metallic sheet is press-formed into a
prescribed shape, thus providing a finished product, which is to be put
into practice. The conventional press-forming apparatus utilizes a pair of
metallic dies. More specifically, the material to be press-formed is held
between the dies. Moving the dies closely to each other causes formation
of a pattern of corrugations serving as the heat transfer face and the
other press-formed portions on the metallic thin sheet of the material to
be press-formed.
The press-forming operation for the heat transfer member has conventionally
been carried out in this manner. The pair of dies forms the pattern of
irregularities of the whole heat transfer member. It is therefore
impossible to form any pattern of corrugations having a size larger than
the molds. As a result, there is a restriction that the size of the heat
transfer member depends on the size of the dies, thus making it impossible
to manufacture the heat transfer member having a large area, due to
limitation of the size of the dies.
In addition, the dies of the press-forming apparatus give the material to
be press-formed a various kind of corrugations. When the pitch of the
pattern of corrugations is not uniform so that the pitch on the one end
side is small, but the pitch on the other side is large, conditions in the
drawing of the material from the non-pressed portion to the pressed
portion are different in the respective patterns of corrugations. A
serious residual strain occurs in the press-formed portion and the
non-pressed portion of the heat transfer member after completion of the
press-forming step. As a result, the heat transfer member may curve
partially or over the entirety, or be deformed, thus causing problems.
SUMMARY OF THE INVENTION
An object of the present invention, which was made to solve the
above-mentioned problems, is therefore to provide a press-forming
apparatus in which a forming section includes a plurality of dies that is
selectively applicable, the press-forming steps are applied to the
material to be press-formed with the use of selected dies so as to form
patterns of corrugations in an appropriate aligned state, thus providing a
proper shape over the entirety of the heat transfer member, while
preventing unfavorable curve or deformation thereof, and the pattern of
corrugations can easily be formed even on the relatively long material to
be press-formed to provide the heat transfer member having the larger size
than the die itself.
In order to attain the aforementioned object, the press-forming apparatus
of the first aspect of the present invention comprises a pair of
press-forming units, which are detachably secured to a movable unit and a
stationary unit that face each other, respectively, so that a metallic
thin sheet material to be press-formed, which is supplied to the
press-forming units in a predetermined feeding direction, subjected to a
press-forming through the press-forming units and then discharged
therefrom as a heat transfer member for a heat exchanger, said heat
transfer member having a predetermined shape,
wherein:
each of said press-forming units comprises (i) a main forming section for
forming on the material to be press-formed a heat transfer face with a
corrugated portion, which has opposite surfaces to be brought into contact
with heat exchange fluids, (ii) a pair of first subsidiary forming
sections, which are disposed on upstream and downstream sides of said main
forming section so as to be adjacent thereto in the feeding direction of
the material to be press-formed, said pair of first subsidiary forming
sections of one of said press-forming units respectively facing said pair
of first subsidiary forming sections of another of said press-forming
units to form an upstream set of first subsidiary forming sections and an
downstream set of first subsidiary forming sections in the feeding
direction of the material to be press-formed and (iii) a forming
section-support base member detachably supporting said main forming
section and said pair of first subsidiary forming sections;
said main forming section having a press-forming face on which there are
formed main corrugation patterned portions that are symmetric with respect
to a central line, which is perpendicular to the feeding direction of the
material to be press-formed, on one hand, and boundary patterned portions
having a predetermined width, on which a plurality of recesses and
projections align in a direction perpendicular to the feeding direction of
the material to be press-formed, on the other hand; and
one of said upstream set of first subsidiary forming sections and one of
said downstream set of first subsidiary forming sections being adjustable
to shift press-forming faces thereof along a pressing direction, so as to
provide switchably a contact mode in which said press-forming faces come
into contact with the material to be press-formed together with the main
forming section to apply a press-forming operation to the material to be
press-formed and a non-contact mode in which the press-forming operation
is not applied thereto.
According to the features of the first aspect of the present invention, the
material to be press-formed is subjected to the press-forming step
utilizing the main forming sections and the first subsidiary forming
sections, which are aligned in the feeding direction of the material to be
press-formed, to form the different patterns of corrugations on the
material to be press-formed, thus providing a heat transfer member.
Particularly, it is possible to form, as an occasion demands, flat
portions or corrugations on the peripheral portion of the material to be
press-formed so as to impart predetermined functions to the heat transfer
member, thus providing the heat transfer members, which cope with many
intended uses. Even when the material to be press-formed is relatively
long, it is possible to apply the press-forming steps to the material to
be press-formed, while selectively utilizing the first subsidiary forming
sections, so as to form the heat transfer face and/or the other
press-formed portions on the entirety of the heat transfer member, thus
enabling the formation of the heat transfer face having the larger size of
the die. The single press-forming step utilizing the main forming sections
makes it possible to provide a state in which the press-formed portions
with corrugations given by the boundary patterned portions, which are
located in the front and rear sides in the feeding direction of the
material to be press-formed, are aligned in the perpendicular direction to
the feeding direction of the material to be press-formed. Accordingly, the
end portions of the material to be press-formed can be provided with
substantially the uniform press-forming conditions, irrespective of
arrangement of the main corrugation pattern portion of the main member.
Substantially the same condition in the drawing of the material from the
non-pressed portion to the pressed portion is provided in the respective
boundary between the pressed portion and the non-pressed portion, thus
avoiding residual strain in any one of the pressed portion and the
non-pressed portion of the heat transfer member after completion of the
press-forming step. It is therefore possible to prevent an unfavorable
deformation of the heat transfer member as the finished product, due to
residual strain.
In the second aspect of the present invention, there may be adopted a
structure in which each of said pair of main forming sections has a
divided structure, which comprises a main member having on a surface
thereof said main corrugated patterned portions and a pair of end members
having on a surface thereof boundary patterned portions; said pair of end
members of one of said pair of main forming sections are mounted on the
forming section-support base member through predetermined resilient
members so as to project from a press-forming face of said main member by
a predetermined length in a state in which a pressing force is not applied
to the material to be press-formed; and said resilient members have
elasticity by which press-forming faces of said end members are retracted
to a place corresponding to the press-forming face of the main member when
a maximum pressing force is applied to the material to be press-formed.
According to the features of the second aspect of the present invention,
each of the pair of main forming sections has the divided structure, which
comprises the main member and the pair of end members, the end members of
one of the pair of main forming sections are mounted on the forming
section-support base member thorough the resilient members so as to come
into contact with the material to be press-formed prior to the contact of
the main member therewith, and the application of the maximum pressing
force causes the main member and the end members to be urged on the
material to be press-formed. It is therefore possible to bring the end
members of the main forming section into initial contact with the material
to be press-formed to hold the material in a proper position, thus
providing a formation of the heat transfer face utilizing the main forming
section with high accuracy.
In the third aspect of the present invention, the apparatus may further
comprise: subsidiary forming section-elevating devices having a
wedge-shape, which are disposed on the forming section-support base member
on a rear side of said pair of first subsidiary forming sections in the
pressing direction, so as to be movable in a horizontal direction, each of
said subsidiary forming section-elevating devices having on a front side
in the pressing direction an inclined surface having a predetermined
inclination angle; and actuators for moving said subsidiary forming
section-elevating devices in the horizontal direction, said one of said
upstream set of first subsidiary forming sections and said one of said
downstream set of first subsidiary forming sections being supported on the
forming section-support base member so as to be adjusted along the
pressing direction, each of said pair of first subsidiary forming sections
being provided on an opposite surface to its press-forming face with an
inclined surface having a same inclination angle as that of the inclined
surface of said subsidiary forming section-elevating device.
According to the features of the third aspect of the present invention, the
subsidiary forming section-elevating devices, which are provided on the
front side in the pressing direction through the first subsidiary forming
section with the inclined surface, are disposed so as to be movable in the
horizontal direction, and sliding the subsidiary forming section-elevating
device in the horizontal direction by the actuator, while bring them into
contact with the first subsidiary forming section, enables the first
subsidiary forming section to be shifted. The subsidiary forming
section-elevating device having the wedge shape bears a strong force
applied to the first subsidiary forming section during the press-forming
operation so as to reduce a reaction force to be applied to the actuator.
As a result, it is possible to lightening the load of the actuator more
remarkably than the case where the actuator is disposed directly on the
rear side in the pressing force. The actuator for shifting the fist
subsidiary forming section can be made small-sized and inexpensive. In
addition, no specific positional adjustment mechanism having a complicated
structure is provided directly in the pressing direction, thus decreasing
the whole height of the apparatus.
In the fourth aspect of the present invention, the apparatus may further
comprise: a pair of second subsidiary forming sections for each of said
pair of press-forming units, said secondary subsidiary forming sections
being detachably disposed on opposite sides in a direction perpendicular
to the feeding direction of the material to be press-formed on the forming
section-support base member, so as to be adjacent to the main forming
section, said pair of second subsidiary forming sections for one of said
pair of press-forming units being mounted on the forming section-support
base member through predetermined resilient members so as to project from
the press-forming face of said main forming section by a predetermined
length in a state in which a pressing force is not applied to the material
to be press-formed; and said resilient members having elasticity by which
press-forming faces of said second subsidiary forming sections are
retracted to a place corresponding to the press-forming face of the main
forming section when a maximum pressing force is applied to the material
to be press-formed.
According to the features of the fourth aspect of the present invention,
the secondary subsidiary forming sections are disposed on the opposite
sides in the direction perpendicular to the feeding direction of the
material to be press-formed on the forming section-support base member, so
as to be adjacent to the main forming section, and the second subsidiary
forming sections for one of the pair of press-forming units are mounted
through the resilient members so as to project from the press-forming face
of the main forming section so that the second subsidiary forming sections
come into contact with the material to be press-formed prior to the
contact of the main member therewith. In addition, the predetermined
press-formed portions can be formed by the second subsidiary forming
sections so as to align with the heat transfer face. It is therefore
possible to provide the portions of the material to be press-formed in the
perpendicular direction of the feeding direction of the material with
desired functions, thus flexibly coping with many intended uses. It is
possible to bring the second subsidiary forming sections into initial
contact with the material to be press-formed to hold the material in a
proper position, thus providing a formation of the heat transfer face
utilizing the main forming section with high accuracy.
In the fifth aspect of the present invention, the apparatus may further
comprise: suction support members being disposed in positions on an
upstream side of the first subsidiary forming section on one of the
forming section-support base members in the feeding direction of the
material to be press-formed, so as to support, under a sucking operation,
the material to be press-formed, which is supplied between the forming
sections while keeping one end of the material to be press-formed in
substantially the same level as the press-forming face of said main
forming section.
According to the features of the fifth aspect of the present invention, the
suction support members are disposed in the predetermined positions on the
upstream side of the first subsidiary forming section on the forming
section-support base member in the feeding direction of the material to be
press-formed so as to hold the portion of the material to be press-formed,
which extends from the dies upstream in the feeding direction of the
material and has not as yet been subjected to the press-forming step,
under the sucking action, even when the material to be press-formed is
relatively long. The material to be press-formed can be kept stably and
stationary, thus preventing the material from unfavorably moving,
irrespective of release of the material from the carrying unit.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a plan view illustrating the lower press-forming unit of a
press-forming apparatus according to an embodiment of the present
invention;
FIG. 2 is a bottom view illustrating the upper press-forming unit of the
press-forming apparatus according to the embodiment of the present
invention;
FIG. 3 is a cross-sectional view in which the cross-section of the lower
press-forming unit cut along the line III--III as shown in FIG. 1 and the
cross-section of the upper press-forming unit cut along the line III--III
as shown in FIG. 2 are combined to each other;
FIG. 4 is a cross-sectional view in which the cross-section of the lower
press-forming unit cut along the line IV--IV as shown in FIG. 1 and the
cross-section of the upper press-forming unit cut along the line IV--IV as
shown in FIG. 2 are combined to each other;
FIG. 5(A) is a schematic perspective view illustrating the structure of the
first and second subsidiary forming sections of the press-forming
apparatus according to the embodiment of the present invention and FIG.
5(B) is a schematic perspective view illustrating a mounting state of the
lower forming section of the second subsidiary forming sections;
FIGS. 6(A) to 6(C) are descriptive views illustrating a press-forming
operation, which is applied to an end area of the material to be
press-formed through the press-forming apparatus according to the
embodiment of the present invention;
FIGS. 7(A) to 7(C) are descriptive views illustrating the press-forming
operation, which is applied to a middle portion of the material to be
press-formed through the press-forming apparatus according to the
embodiment of the present invention;
FIGS. 8(A) to 8(C) are descriptive views illustrating the press-forming
operation, which is applied to the other end area of the material to be
press-formed through the press-forming apparatus according to the
embodiment of the present invention; and
FIG. 9 is a schematic plan view of a heat transfer member, which is
manufactured by the press-forming apparatus according to the embodiment of
the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Now, embodiments of a press-forming apparatus of the present invention will
be described in detail below with reference to FIGS. 1 to 9. FIG. 1 is a
plan view illustrating the lower press-forming unit of a press-forming
apparatus according to an embodiment of the present invention; FIG. 2 is a
bottom view illustrating the upper press-forming unit of the press-forming
apparatus according to the embodiment of the present invention; FIG. 3 is
a cross-sectional view in which the cross-section of the lower
press-forming unit cut along the line III--III as shown in FIG. 1 and the
cross-section of the upper press-forming unit cut along the line III--III
as shown in FIG. 2 are combined to each other; FIG. 4 is a cross-sectional
view in which the cross-section of the lower press-forming unit cut along
the line IV--IV as shown in FIG. 1 and the cross-section of the upper
press-forming unit cut along the line IV--IV as shown in FIG. 2 are
combined to each other; FIG. 5(A) is a schematic perspective view
illustrating the structure of the first and second subsidiary forming
sections of the press-forming apparatus according to the embodiment of the
present invention and FIG. 5(B) is a schematic perspective view
illustrating a mounting state of the lower forming section of the second
subsidiary forming sections; FIGS. 6(A) to 6(C) are descriptive views
illustrating a press-forming operation, which is applied to an end area of
the material to be press-formed through the press-forming apparatus
according to the embodiment of the present invention; FIGS. 7(A) to 7(C)
are descriptive views illustrating the press-forming operation, which is
applied to a middle portion of the material to be press-formed through the
press-forming apparatus according to the embodiment of the present
invention; FIGS. 8(A) to 8(C) are descriptive views illustrating the
press-forming operation, which is applied to the other end area of the
material to be press-formed through the press-forming apparatus according
to the embodiment of the present invention; and FIG. 9 is a schematic plan
view of a heat transfer member, which is manufactured by the press-forming
apparatus according to the embodiment of the present invention.
As shown in each of FIGS. 1 to 9, the press-forming apparatus according to
the embodiment of the present invention includes a pair of press-forming
units 1, 1, which are detachably secured to a movable unit and a
stationary unit that face each other, respectively, so that a metallic
thin sheet material 100 to be press-formed, see FIGS. 6A to 6C, which is
supplied to the press-forming units 1, 1 in a predetermined feeding
direction, subjected to a press-forming through the press-forming units 1,
1 and then discharged therefrom as a heat transfer member for a heat
exchanger, which has a predetermined shape. The structural components
other than the press-forming units 1, 1 of the press-forming apparatus are
known, and description thereof is omitted.
The press-forming units 1, 1 are provided with a pair of main forming
sections 10, 10, two pairs of first subsidiary forming sections 20, 30,
two pairs of second subsidiary forming sections 40, 50, a pair of forming
section-support base members 60, 60, subsidiary forming section-elevating
devices 70 for moving up and down the subsidiary forming sections and
actuators 80 for the subsidiary forming section-elevating devices 70, and
suction support members 90.
The pair of main forming sections 10, 10 form on the material to be
press-formed a heat transfer face with corrugated portions, having
opposite surfaces, which are to be brought into contact with heat exchange
fluids.
Each pair of the first subsidiary forming sections 20, 30 are disposed on
the upstream and downstream sides of respective one of the pair of main
forming sections 10, 10 so as to be adjacent thereto in the feeding
direction of the material to be press-formed.
Each pair of the second subsidiary forming sections 40, 50 are detachably
disposed on the opposite sides in the direction perpendicular to the
feeding direction of the material to be press-formed, so as to be adjacent
to the main forming sections 10, 10.
The upper forming section-support base member 60 is used to support (i) the
upper main forming section 10, (ii) the upper first subsidiary forming
sections 20, 30 and (iii) the upper second subsidiary forming sections 40,
50. The lower forming section-support base member 60 is used to support
the lower main forming sections 10, (ii) the lower first subsidiary
forming sections 20, 30 and (iii) the lower second subsidiary forming
sections 40, 50.
The subsidiary forming section-elevating devices 70 and the actuators 80
make a positional adjustment of the first subsidiary forming sections 20,
30 in the pressing direction so as to provide switchably a contact mode in
which the first subsidiary forming sections 20, 30 come into contact with
the material 100 to be press-formed and a non-contact mode in which they
do not come into contact with the material 100 to be press-formed.
The suction support members 90 are disposed in two positions on the
upstream side of the forming sections on the one of the pair of forming
section-support base members 60, 60 in the feeding direction of the
material to be press-formed, so as to support, under the sucking
operation, the material to be press-formed, which has been supplied
between the forming sections.
Each of the main forming sections 10, 10 has a three-part structure
composed of a main member 11 and a pair of end members 12. The end members
12, 12 are disposed respectively on the opposite sides of the main member
11 in the feeding direction of the material to be press-formed so as to be
adjacent to the main member 11. Each of the end members 12, 12 is provided
on the surface thereof with a boundary portion having a predetermined
width with patterned corrugations, which are aligned by a predetermined
pitch in the perpendicular direction to the feeding direction of the
material to be press-formed. The above-mentioned pair of main forming
sections 10, 10 having such a three-part structure are secured to the pair
of forming section-support base members 60, 60, respectively.
The upper main member 11, i.e., the upper die 11a is secured to the upper
forming section-support base member 60 so that its pressing-forming face
faces downward. The lower main member 11, i.e., the lower die 11b is
secured to the lower forming section-support base member 60 so that its
pressing-forming face faces upward to the upper die 11a. The upper end
members 12, 12, i.e., the upper dies 12a, 12a are secured to the upper
forming section-support base member 60 so that their press-forming faces
face downward. The lower end members 12, 12, i.e., the lower die 12b, 12b
are disposed on the lower forming section-support base member 60 so that
their pressing-forming faces face upward to the upper dies 12a, 12a,
respectively. The upper die 11a of the main member 11 is integrally formed
with upper dies 41, 51 of the second subsidiary forming sections 40, 50.
The upper dies 12a, 12a of the end members 12, 12 are integrally formed
with upper dies 21, 31 of the first subsidiary forming sections 20, 30,
respectively.
Each of the lower dies 12b, 12b of the end members 12, 12 is mounted on the
lower forming section-support base member 60 through a resilient member 13
so that the press-forming face of the lower die 12b projects from the
press-forming face of the main member 11 by a predetermined length in a
state in which a pressing force is not applied to the material to be
press-formed. The resilient member 13 is formed of a sheet of resilient
material such as rubber or polyurethane, which has elasticity by which the
press-forming face of the lower die 12b can be retracted to a place
corresponding to the press-forming face of the main member 11.
The first subsidiary forming sections 20, 30 are composed of the upper dies
21, 31, which are secured to the upper forming section-support base member
60 so that their press-forming faces face downward, and the lower dies 22,
32, which are disposed to face the above-mentioned upper dies 21, 31,
respectively, so that their press-forming faces face upward. Each of the
first subsidiary forming sections 20, 30 is provided with a press-forming
face in which a flat portion having a predetermined width is continuously
formed and a plurality of recesses and projections are formed so as to be
aligned in the perpendicular direction to the feeding direction of the
material to be press-formed.
The lower dies 22, 32 of the first subsidiary forming sections 20, 30 are
supported on the lower forming section-support base member 60 so as to be
adjusted in the pressing direction and provided on the opposite surface to
the press-forming face with inclined surfaces having a predetermined
inclination angle. Positional adjustment of the subsidiary forming
section-elevating device 70, which slidably comes into contact with the
above-mentioned inclined surface, makes it possible to provide switchably
a pressing state in which the lower dies 22, 32 of the first subsidiary
forming sections 20, 30 come into contact with the material 100 to be
press-formed, together with the above-mentioned main forming section 10,
and a non-pressing state in which the lower dies 22, 32 do not come into
contact with the material 100 to be press-formed.
The second subsidiary forming sections 40, 50 are composed of the upper
dies 41, 51, which are secured to the upper forming section-support base
member 60 so that their press-forming faces face downward, and the lower
dies 42, 52, which are disposed to face the above-mentioned upper dies 41,
51, respectively, so that their press-forming faces face upward. The
second subsidiary forming sections 40, 50 are symmetrically placed with
respect to the central line in the feeding direction of the material to be
press-formed. The second subsidiary forming section 40 (50) is provided
with the press-forming face in which a projection 44 (54) and a recess 45
(55) are formed and a corrugated portion having a predetermined width is
provided excepting the area of the above-mentioned projection 44 (54) and
recess 45 (55). The corrugations align in a parallel direction to the
feeding direction of the material to be press-formed, thus providing a
smooth sine curve in the cross-section. The remaining portions have a flat
surface so as to convert predetermined portions of the material 100 to be
press-formed into a flange portion 220 of a heat transfer member 200 to be
manufactured.
The lower dies 42, 52 of the second subsidiary forming sections 40, 50 are
mounted on the lower forming section-support base member 60 through
resilient members 43, 53 so that the press-forming faces of the lower dies
42, 52 project from the press-forming face of the main member 11 by a
predetermined length in a state in which a pressing force is not applied
to the material to be press-formed. The resilient members 43, 53 are
formed of a sheet of resilient material such as rubber or polyurethane,
which has elasticity by which the press-forming faces of the lower dies
42, 52 can be retracted to a place corresponding to the press-forming face
of the main member 11.
The lower dies 42, 52 of the second subsidiary forming sections 40, 50 are
provided with pins 46, 56 on the downstream side thereof in the feeding
direction of the material to be press-formed, respectively. These pins 46,
56 are retractable from the surfaces of the lower dies 42, 52,
respectively. The material 100 to be press-formed, which is supplied
between the forming sections in a predetermined position by means of a
carrying unit (not shown), comes into contact with the above-mentioned
pins 46, 56, thus providing a precise positional determination of the
material 100 to be press-formed. Thus, the pins 46, 56 serve as a stopper
during the first press-forming step applied to the material 100 to be
press-formed. In case where the material 100 to be press-formed is
subjected to a plurality of press-forming steps, the pins 46, 56 are
retracted from the surfaces of the lower dies 42, 52 by a small force upon
movement of the material 100 to be press-formed, which has been subjected
to the press-forming step(s), thus preventing the movement of the material
100 to be press-formed.
In addition, the lower dies 42, 52 of the second subsidiary forming
sections 40, 50 are provided with guide pins 47, 57, which control the
movement of the material 100 to be press-formed in the perpendicular
direction to the feeding direction of the material 100 to be press-formed.
Even when the material 100 to be press-formed is relatively long, these
guide pins 47, 57 keep the material 100 to be press-formed in a proper
position in cooperation with the other guide pins provided in the forming
section-support base member 60, thus providing a stable press-forming
operation for the material 100 to be press-formed. Even when the material
100 to be press-formed has a winding shape, the adjustment of these guide
pins causes a proper positional determination of the material 100 to be
press-formed relative to the forming sections.
The lower forming section-support base member 60 is provided with the
subsidiary forming section-elevating devices 70, the actuators 80 and the
suction support members 90, in addition to the respective forming
sections. Further, the lower forming section-support base member 60 is
provided, on the upstream side (i.e., the feeding side) of the lower dies
42, 52 of the second subsidiary forming section 40, 50 in the feeding
direction of the material to be press-formed, with additional guide pins
61. These additional guide pins 61 are placed in four positions of the
lower forming section-support base member 60, which define a square area
thorough which the material 100 to be press-formed is to pass, so as to
control the movement of the material 100 to be press-formed in the
perpendicular direction to the feeding direction thereof. When the
material 100 to be press-formed is relatively long, the six guide pins
including the guide pins provided in the second subsidiary forming section
keep the material 100 to be press-formed in a proper position.
In addition, the lower forming section-support base member 60 is provided,
on the downstream side (i.e., the discharging side) of the second
subsidiary forming sections 40, 50 in the feeding direction of the
material to be press-formed, with projections 62 and recesses 63, which
are similar to the above-described projections 44, 45 and recesses 45, 55
of the second subsidiary forming sections 40, 50. The distance between the
projection 62 and the recess 63 is equal to the distance between the
above-described projection 44 and recess 45. These projections 62 and
recesses 63 are displaced from the projections 44, 45 and recesses 45, 55
of the second subsidiary forming sections 40, 50 by a distance
corresponding to the feeding amount of the material to be press-formed for
a single press-forming operation. In case where the material 100 to be
press-formed is subjected to a plurality of press-forming steps, the
material 100 to be press-formed, which has been subjected to a single
press-forming step to provide a projection and a recess formed thereon, is
transferred to the next position so that the thus formed projection and
recess are precisely fitted into the recess 63 and the projection 62 of
the forming section-support base member 60, thereby making a precise
positional determination of the material 100 to be press-formed.
The subsidiary forming section-elevating devices 70 are disposed on the
lower forming section-support base member 60 on the rear side of the lower
dies 22, 32 of the first subsidiary forming sections 20, 30 in the
pressing direction, so as to be movable in the horizontal direction. Each
of the subsidiary forming section-elevating devices 70 includes a
wedge-shaped member, which has on the front side in the pressing direction
an inclined surface having the same inclination angle of the inclined
surface of the above-described lower dies 22, 32. The wedge-shaped member
comes slidably into contact with the lower die 22, 32 to convert the
horizontal motion of the wedge-shaped member into the vertical motion of
the lower die 22, 32 through the above-mentioned inclined surface.
The actuators 80 are disposed on the lower forming section-support base
member 60 so as to be adjacent to the respective subsidiary forming
section-elevating devices 70. Any one of the actuators 80 moves the
subsidiary forming section-elevating device 70 in the horizontal direction
by a predetermined stroke. A known air-cylinder is for example used as the
actuator 80.
The suction support members 90 are disposed on the lower forming
section-support base member 60 on the upstream side of the first
subsidiary forming section 30 in the feeding direction of the material 100
to be press-formed. A known vacuum suction cup or pad may be used as the
suction support member 90 so that the tip portion thereof is placed in the
same level as the press-forming face of the main member 11 of the main
forming section. The suction support members 90 hold the material 100 to
be press-formed at the lower surface thereof under a sucking action. In
case where the material 100 to be press-formed is ferrous, a device for
providing an electromagnetic sucking action, such as an electromagnet may
be used as the suction support member 90.
The main member 11 and the end members 12, of which the main forming
section 10 is composed, the first subsidiary forming sections 20, 30 and
the second subsidiary forming sections 40, 50 are detachably disposed on
the forming section-support base member 60. These structural elements may
be changed to the other elements having the different press-forming face
in accordance with the press-forming conditions, thus making it possible
to provide the material 100 to be press-formed with an appropriate shape
for the heat transfer member 200.
Detection devices (not shown) for determining as whether or not an area to
be press-formed of the material 100 reaches a predetermined position where
the press-forming step is carried out by the forming sections, are
disposed in the vicinity of the first subsidiary forming sections 20, 30
and the second subsidiary forming sections 40, 50.
The material 100 to be press-formed, which is a metallic thin sheet having
a rectangular shape, is supplied into the press-forming apparatus in the
single feeding direction to be converted into the heat transfer member 200
with corrugated portions, in which the heat transfer face 210 having the
opposite surfaces that are to be brought into contact with heat exchange
fluids is formed in the central portion by a plurality of press-forming
steps utilizing the main forming sections 10, on the one hand, and the
flange portion 220 is formed so as to surround the heat transfer face 210,
on the other hand (see FIG. 9). The heat transfer face 210 serves as the
zone, which has the predetermined corrugations that are optimized to bring
the opposite surfaces of the heat transfer face 210 into contact with the
high and low temperature fluids, respectively, to achieve the heat
transfer.
Now, description will be given below of a press-forming operation applied
to the material 100 to be press-formed, utilizing the press-forming
apparatus according to the embodiment of the present invention. The
description will be given on the assumption that any defects of the
materials 100 to be press-formed have been detected in an appropriate
manner and only the materials 100 having no defects are supplied to the
press-forming step.
First, the press-forming step utilizing the first subsidiary forming
sections 20, which is placed on the most downstream side in the feeding
direction of the material 100 to be press-formed, the main forming
sections 10 and the second subsidiary forming sections 40, 50 is carried
out. The sliding action of the forming section-elevating device 70, which
is caused by the actuator 80, causes the lower die 32 of the first
subsidiary forming section 30 to descend relative to the other lower dies
12b, 22, 42, 52, in the initial state in which the upper and lower dies of
the respective forming sections are apart from each other. Then, the
carrying unit (not shown) transfers the material 100 to be press-formed
into the press-forming apparatus so that one end of the material 100 to be
press-formed is inserted between the upper and lower dies.
When the one end of the material 100 to be press-formed reaches the
predetermined position where the press-forming step is carried out, the
feeding step of the material 100 is temporarily stopped. The suction
support members 90 come into contact with the lower surface of the
material 100. After there is ensured a state in which the suction support
members 90 hold the material 100 under a sucking action, the carrying unit
releases the material 100 and moves away from the supper and lower dies.
Even when the material 100 is relatively long, the suction support members
90 hold the portion of the material 100, which extends from the dies
upstream in the feeding direction of the material 100 and has not as yet
been subjected to the press-forming step, under the sucking action, so as
to keep the material 100 stable and stationary, thus preventing the
material 100 from unfavorably moving, irrespective of release of the
material 100 from the carrying unit. Consequently, the subsequent
press-forming step can be carried out with high accuracy.
When there is ensured a state in which only the material 100 exists between
the upper and lower dies (see FIG. 6(A)), the respective upper dies of the
forming sections descend toward the corresponding lower dies thereof. The
end members 12 in which the lower die 12b projects relative to the main
member 11, and the second subsidiary forming sections 40, 50 come first
into contact with the material 100 so as to make a positional
determination of the material 100, thus preventing an unfavorable
deviation thereof (see FIG. 6(B)). Further descending the upper dies
toward the corresponding lower dies causes the lower dies 12b of the end
members 12 and the lower dies 42, 52 of the second subsidiary forming
sections 40, 50 to descend due to elastic deformation of the resilient
members 13, 43, 53 so that the remaining dies also come into contact with
the material 100. When the maximum pressing force is applied to the
material 100, the lower dies 12b of the end members 12 and the lower dies
42, 52 of the second subsidiary forming sections 40, 50 are placed in the
same level as the main member 11. Accordingly, the material 100 is pressed
by means of the main members 11, the end members 12 and the second
subsidiary forming sections 40, 50 (see FIG. 6(C)).
The one end of the material 100 is held by the main forming sections 10,
the first subsidiary forming section 20 and the second subsidiary forming
sections 40, 50 and then a uniform pressure is applied to the material 100
to form the predetermined press-formed portion according to the respective
dies on the material 100. At this stage, the lower die 32 of the first
subsidiary forming section 30 is further away from the material 100 than
the remaining dies and does not come into contact with the material 100 at
all, with the result that the press-forming step utilizing the first
subsidiary forming section 20 is not carried out. The suction support
members 90 halt the sucking action to release the material 100 when the
respective dies come into contact with the material 100. After completion
of the press-forming step of the one end area of the material 100, all the
upper dies ascend so as to be away from the corresponding lower dies. The
feeding step of the material 100 is carried again by means of the carrying
unit.
