EP1138410A2 - Apparatus for performing a hydroforming operation - Google Patents
Apparatus for performing a hydroforming operation Download PDFInfo
- Publication number
- EP1138410A2 EP1138410A2 EP01302975A EP01302975A EP1138410A2 EP 1138410 A2 EP1138410 A2 EP 1138410A2 EP 01302975 A EP01302975 A EP 01302975A EP 01302975 A EP01302975 A EP 01302975A EP 1138410 A2 EP1138410 A2 EP 1138410A2
- Authority
- EP
- European Patent Office
- Prior art keywords
- die
- hydroforming
- workpiece
- platen
- cylinders
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
Images
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21D—WORKING OR PROCESSING OF SHEET METAL OR METAL TUBES, RODS OR PROFILES WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21D37/00—Tools as parts of machines covered by this subclass
- B21D37/14—Particular arrangements for handling and holding in place complete dies
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21D—WORKING OR PROCESSING OF SHEET METAL OR METAL TUBES, RODS OR PROFILES WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21D26/00—Shaping without cutting otherwise than using rigid devices or tools or yieldable or resilient pads, i.e. applying fluid pressure or magnetic forces
- B21D26/02—Shaping without cutting otherwise than using rigid devices or tools or yieldable or resilient pads, i.e. applying fluid pressure or magnetic forces by applying fluid pressure
- B21D26/021—Deforming sheet bodies
- B21D26/025—Means for controlling the clamping or opening of the moulds
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21D—WORKING OR PROCESSING OF SHEET METAL OR METAL TUBES, RODS OR PROFILES WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21D26/00—Shaping without cutting otherwise than using rigid devices or tools or yieldable or resilient pads, i.e. applying fluid pressure or magnetic forces
- B21D26/02—Shaping without cutting otherwise than using rigid devices or tools or yieldable or resilient pads, i.e. applying fluid pressure or magnetic forces by applying fluid pressure
- B21D26/033—Deforming tubular bodies
- B21D26/039—Means for controlling the clamping or opening of the moulds
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21D—WORKING OR PROCESSING OF SHEET METAL OR METAL TUBES, RODS OR PROFILES WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21D37/00—Tools as parts of machines covered by this subclass
- B21D37/10—Die sets; Pillar guides
- B21D37/12—Particular guiding equipment, e.g. pliers; Special arrangements for interconnection or cooperation of dies
Definitions
- This invention relates in general to an apparatus for performing a hydroforming operation on a closed channel workpiece.
- this invention relates to an improved structure for such a hydroforming apparatus that is relative simple and inexpensive in structure and operation and is well suited for performing a hydroforming operation on relatively long workpieces, such as side rails for a vehicle frame assembly.
- Hydroforming is a well known metal working process that uses pressurized fluid to deform a closed channel workpiece, such as a tubular member, outwardly into conformance with a die cavity having a desired shape.
- a typical hydroforming apparatus includes a frame having a two or more die sections that are supported thereon for relative movement between opened and closed positions.
- the die sections have cooperating recesses formed therein that together define a die cavity having a shape corresponding to a desired final shape for the workpiece.
- the die sections When moved to the opened position, the die sections are spaced apart from one another to allow a workpiece to be inserted within or removed from the die cavity.
- the die sections When moved to the closed position, the die sections are disposed adjacent to one another so as to enclose the workpiece within the die cavity.
- the die cavity is usually somewhat larger than the workpiece to be hydroformed, movement of the two die sections from the opened position to the closed position may, in some instances, cause some mechanical deformation of the hollow member.
- the workpiece is then filled with a fluid, typically a relatively incompressible liquid such as water.
- the pressure of the fluid within the workpiece is increased to such a magnitude that the workpiece is expanded outwardly into conformance with the die cavity.
- Hydroforming is an advantageous process for forming vehicle frame components and other structures because it can quickly deform a workpiece into a desired complex shape.
- the die sections are arranged such that an upper die section is supported on a ram of the apparatus, while a lower die section is supported on a bed of the apparatus.
- a mechanical or hydraulic actuator is provided for raising the ram and the upper die section upwardly to the opened position relative to the lower die section, allowing the previously deformed workpiece to be removed from and the new workpiece to be inserted within the die cavity.
- the actuator also lowers the ram and the upper die section downwardly to the closed position relative to the lower die section, allowing the hydroforming process to be performed.
- a mechanical clamping device is usually provided.
- the mechanical clamping device mechanically engages the die sections (or, alternatively, the ram and the base upon which the die sections are supported) to prevent them from moving apart from one another during the hydroforming process. Such movement would obviously be undesirable because the shape of the die cavity would become distorted, resulting in unacceptable variations in the final shape of the workpiece.
- the hydroforming process involves the application of a highly pressurized fluid within the workpiece to cause expansion thereof.
- the magnitude of the pressure of the fluid within the workpiece will vary according to many factors, one of which being the physical size of the workpiece to be deformed.
- the magnitude of the pressure of the fluid supplied within the workpiece during the hydroforming operation is relatively small.
- the amount of the outwardly-directed force exerted by the workpiece on the die sections during the hydroforming operation is also relatively small.
- only a relatively small amount of inwardly-directed force is required to be exerted by the hydroforming apparatus to counteract the outwardly-directed force so as to maintain the die sections in the closed position during the hydroforming operation. Consequently, the physical size and strength of the hydroforming apparatus when used for deforming relatively small or thin-walled workpieces is no greater than a typical mechanical press for performing a similar operation.
- This invention relates to an improved structure for a hydroforming apparatus that is capable of deforming relatively large and thick-walled workpieces, yet which is relatively small, simple, and inexpensive in construction and operation.
- the hydroforming apparatus includes an upper platen and a lower platen that are connected together by tie rods extending through respective compression tubes.
- An upper die section is supported on the upper platen, while a lower die section is supported on the lower platen for vertical movement relative to the upper die section.
- the upper and lower die sections have respective recessed areas formed therein that define a hydroforming die cavity. When the lower die section is moved to a lowered position, a workpiece can be disposed in the recessed area formed therein.
- the lower die section and the workpiece are elevated by cylinders such that the workpiece is enclosed within the hydroforming cavity and mechanically deformed by the cooperated upper and lower die sections.
- a hydroforming support block is then moved between the hydroforming die and the lower platen.
- a cylinder array containing a plurality of pistons is next hydraulically actuated so as to securely clamp the hydroforming die between the cylinder array and the support block. While the cylinder array is actuated, pressurized fluid is supplied within the workpiece, causing it to deform into conformance with the hydroforming die cavity.
- the illustrated hydroforming apparatus 10 is of generally modular construction, including three hydroforming modules indicated at 11, 12, and 13.
- the modules 11, 12, and 13 are generally identical in structure and operation and can be arranged in side-by-side manner. Although three of such hydroforming modules 11, 12, and 13 are shown, it will be appreciated that the hydroforming apparatus 10 may be formed having a greater or lesser number of such modules 11, 12, and 13. Alternatively, the hydroforming apparatus 10 need not be formed having such a modular construction.
- Each of the modules 11, 12, and 13 of the hydroforming apparatus 10 includes an upper platen, indicated generally at 20.
- the illustrated upper platen 20 is generally box-shaped in construction, including an upper horizontally extending structural plate 21, a lower horizontally extending structural plate 22, a front vertically extending structural plate 23, and a rear vertically extending structural plate 24.
- the structural plates 21, 22, 23, and 24 are connected to one another in any conventional manner, such as by welding.
- a first pair of laterally extending front reinforcement plates 25 and a second pair of laterally extending rear reinforcement plates 26 can be connected to the structural plates 21, 22, 23, and 24 in any conventional manner, such as by welding, to increase the overall strength and rigidity of the upper platen 20.
- Each of the modules 11, 12, and 13 of the hydroforming apparatus 10 also includes a lower platen, indicated generally at 30.
- the illustrated lower platen 30 is also generally box-shaped in construction, including an upper horizontally extending structural plate 31, a lower horizontally extending structural plate 32, a front vertically extending structural plate 33, and a rear vertically extending structural plate 34.
- the structural plates 31, 32, 33, and 34 are connected to one another in any conventional manner, such as by welding.
- a first pair of laterally extending front reinforcement plates 35 (only one is illustrated) and a second pair of laterally extending rear reinforcement plates 36 (only one is illustrated) can be connected to the structural plates 21, 22, 23, and 24 in any conventional manner, such as by welding, to increase the overall strength and rigidity of the lower platen 30.
- the upper platen 20 and the lower platen 30 are connected together by a pair of vertically extending compression tubes or members 40 and 41.
- the illustrated compression tubes 40 and 41 are generally hollow and cylindrical in shape and are preferably formed having upper and lower ends 40a and 40b (see Fig. 2) of increased wall thickness.
- the compression tubes 40 and 41 are secured to one or more portions of both the upper platen 20 and the lower platen 30 in any conventional manner, such as by welding.
- a transversely extending supporting plate 42 may be connected between the compression tubes 40 and 41 in any conventional manner, such as by welding, to increase the overall strength and rigidity of the compression tubes 40 and 41 and the hydroforming apparatus 10 as a whole.
- a tie rod 43 extends through each of the compression tubes 40 and 41 from the upper platen 20 to the lower platen 30.
- Each of the tie rods 43 is a generally solid cylindrical member having an upper end portion 43a that extends above the upper horizontally extending structural plate 21 of the upper platen 20 and a lower end portion 43b that extends below the lower horizontally extending structural plate 32 of the lower platen 30.
- the upper and lower end portions 43a and 43b of the tie rod 43 are threaded, and nuts 44 or similar retaining devices are threaded onto such threaded end portions 43a and 43b to connect the tie rods 43 to the compression tubes 41.
- a backing plate 45 extends between the lower horizontally extending structural plate 22 of the upper platen 20 and the upper horizontally extending structural plate 31 of the lower platen 30 for a purpose that will also be explained below.
- a pair of upper die clamping assemblies 50 and 51 are provided on the upper platen 20.
- the upper die clamping assemblies 50 and 51 are secured to the lower horizontally extending structural plate 22 of the upper platen 20 in any conventional manner, such as by welding.
- the upper die clamping assemblies 50 and 51 have respective die locking cylinders 52 and 53 supported thereon.
- the die locking cylinders 52 and 53 include respective locking pins 52a and 53a that are selectively movable between retracted and extended positions.
- the die locking cylinders 52 and 53 are hydraulically actuated, although such is not required.
- the purpose for the upper die clamping assemblies 50 and 51 will be explained below.
- a cylinder array 54 is also provided on the upper platen 20.
- the cylinder array 54 is secured to the lower horizontally extending structural plate 22 of the upper platen 20 in any conventional manner, such as by welding, and extends laterally between upper die clamping assemblies 50 and 51.
- the cylinder array 54 has a plurality of hollow cylinders 55 formed in the lower surface thereof. The quantity and location of such hollow cylinders 55 may be determined as necessary to perform the hydroforming operation described below.
- a piston 56 is disposed in each of the hollow cylinders 55 for limited upward and downward movement in the manner described below.
- a plurality of passageways 57 are formed through the cylinder array 54 such that the hollow cylinders 55 are in fluid communication with one another. The passageways 57 selectively communicate with a source of pressurized fluid (not shown). The purpose for the cylinder array 54 and the pistons 56 will be explained below.
- a retainer plate 60 is provided on the cylinder array 54 for retaining the pistons 56 within the cylinders 55.
- the retainer plate 60 is supported on the cylinder array 54 for limited upward and downward movement by a plurality of support assemblies, indicated generally at 61.
- a first pair of support assemblies 61 are provided on the front side of the cylinder array 54, and a second pair of support assemblies (not shown) are provided on the rear side of the cylinder array 54.
- any number of such support assemblies 61 may be provided at any desired locations.
- the structure of one of the support assemblies 61 is illustrated in detail in Fig. 3. As shown therein, the support assembly 61 includes a backing plate 62 having a pair of upstanding ears 63 formed thereon or secured thereto.
- Each of the ears 63 has an opening 63a formed therethrough, and the openings 63a are vertically aligned with one another.
- a rod 64 extends through the aligned openings 63a formed through the ears 63 for vertical sliding movement relative thereto.
- the rod 64 has a lower end that is secured to a lug 60a formed on or secured to the retainer plate 60 for movement therewith.
- the rod 64 further has an upper end that has an enlarged nut 65 or other retaining device formed thereon or secured thereto.
- the nut 65 is larger in size than the openings 63a formed through the ears 63.
- the retainer plate 60 and the rods 64 can move upwardly and downwardly relative to the cylinder array 54 between an uppermost position, wherein the retainer plate 60 abuts the cylinder array 54, and a lowermost position, wherein the nut 65 engages the upper surface of the upper ear 63.
- the purpose for this limited relative movement will be explained below.
- a crosshead 70 is supported on the upper horizontally extending structural plate 31 of the lower platen 30.
- the crosshead 70 is supported for limited vertical movement relative to the upper horizontally extending structural plate 31 by one or more lift cylinders 71 (two of which are illustrated in Fig. 2) and one or more crush cylinders 72 (one of which is illustrated in Fig. 2).
- the lift cylinders 71 are secured to the upper horizontally extending structural plate 31 or are otherwise supported on the lower platen 30.
- Each of the lift cylinders 71 has a piston 71a that extends upwardly therefrom through an opening formed through the upper horizontally extending structural plate 31 and is adapted to engage the lower surface of the crosshead 70.
- the lift cylinders 71 are preferably relatively small in size so as to selectively effect relatively high velocity, low force exertion movement of the pistons 71a and the crosshead 70.
- the lift cylinders 71 are preferably hydraulically actuated, although such is not necessary.
- the crush cylinders 72 are also secured to the upper horizontally extending structural plate 31 or are otherwise supported on the lower platen 30. Each of the crush cylinders 72 has a piston 72a that extends upwardly therefrom through an opening formed through the upper horizontally extending structural plate 31 and is adapted to engage the lower surface of the crosshead 70.
- the crush cylinders 72 are preferably relatively large in size so as to selectively effect relatively low velocity, high force exertion movement of the pistons 71a and the crosshead 70.
- the crush cylinders 72 are also preferably hydraulically actuated, although such is not necessary. The quantity and location of such lift cylinders 71 and crush cylinders 72 may be determined as necessary to perform the hydroforming operation described below.
- a die change spacer block 75 is supported on the upper horizontally extending structural plate 31 of the lower platen 30.
- the die change spacer block 75 is supported for limited horizontal movement relative to the upper horizontally extending structural plate 31 by one or more spacer block cylinders 76 that may be supported on the upper horizontally extending structural plate 31 of the lower platen 30.
- the die change spacer block 75 can be moved between a retracted position (illustrated in Fig. 2) and an extended position by the spacer block cylinders 76.
- One or more slots 75a are formed in the die change spacer block 75. The purpose for the die change spacer block 75 and the slots 75a will be explained below.
- a hollow die transfer housing 80 is connected to the upper horizontally extending structural plate 31 or otherwise supported on the lower platen 30. As shown in Fig. 1, the illustrated die transfer housing 80 extends laterally throughout all of the hydroforming modules 11, 12, and 13 of the hydroforming apparatus 10, although such is not necessary.
- the die transfer housing 80 has a plurality of rollers 81 or other transport mechanisms provided on the upper surface thereof.
- a hydroforming die including an upper die mounting plate 82, an upper die section 83, a lower die section 84, and a lower die mounting plate 85, is supported on the rollers 81 of the die transfer housing 80.
- the upper surface of the upper die section 83 is secured to the upper die mounting plate 82, while the lower surface of the-upper die section 83 has a recessed area 83a formed therein.
- the lower surface of the lower die section 84 is secured to the lower die mounting plate 85, while the upper surface of the lower die section 84 has a recessed area 84a formed therein.
- the recessed areas 83a and 84a cooperate to define a hydroforming cavity that extends transversely throughout the hydroforming die.
- the upper die mounting plate 82 has recesses 82a and 82b respectively formed in the front and rear sides thereof. The purpose for these recesses 82a and 82b will be explained below.
- a hydroforming support block 90 is supported within the hollow die transfer housing 80.
- the hydroforming support block 90 is supported for limited horizontal movement relative to the die transfer housing 80 by one or more support block cylinders 91 that may be provided within the die transfer housing 80 or supported in any other desired location on the hydroforming apparatus 10.
- the hydroforming support block 90 can be moved between a retracted position (illustrated in Fig. 2) and an extended position by the support block cylinders 91.
- One or more slots 90a are formed in the hydroforming support block 90.
- the purpose for the hydroforming support block 90 and the slots 90a will be explained below.
- a pair of die change cylinders 92 are secured to the backing plate 45 or otherwise supported on the hydroforming apparatus 10. The purpose for the die change cylinders 92 will be explained below.
- the hydroforming die must be installed within the hydroforming apparatus 10.
- the various components of the hydroforming apparatus 10 are oriented in the retracted positions illustrated in Fig. 2, and the hydroforming die is disposed on top of the rollers 81 provided on the upper surface of the die transfer housing 80.
- the passageways 57 formed through the cylinder array 54 do not communicate with the source of pressurized fluid.
- the pistons 56 and the retainer plate 60 depend from the cylinder array 60 under the influence of gravity to the extent permitted by the support assemblies 61, no pressure is exerted thereby.
- the lift cylinders 71 are initially actuated as shown in Fig. 4 to extend the pistons 71a, thereby elevating the crosshead 70 to an elevated position.
- the upper surface of the crosshead 70 is disposed somewhat higher than the lower surface of the hydroforming die supported on the rollers 81 provided on the upper surface of the die transfer housing 80.
- the lower surface of the crosshead 70 is disposed somewhat higher than the upper surface of the die change spacer block 75.
- the spacer block cylinders 76 are actuated to extend the die change spacer block 75 laterally beneath the crosshead 70.
- one or more slots 75a are formed in the die change spacer block 75. These slots 75a are provided to permit this lateral movement of the die change spacer block 75 to occur while the pistons 71a of the lift cylinders 71 are extended. Such pistons 71a are received within the clearance provided by the slots 75a so that no interference with the die change spacer block 75 occurs. Thereafter, the pistons 71a of the lift cylinders 71 are retracted such that the crosshead 70 is lowered onto the die change spacer block 75, as also shown in Fig. 5.
- the crosshead 70 and the die change spacer block 75 are sized such that when the crosshead 70 is lowered onto the die change spacer block 75, the upper surface of the crosshead 70 is precisely flush with the lower surface of the hydroforming die disposed on top of the rollers 81 provided on the upper surface of the die transfer housing 80.
- the hydroforming die can be moved laterally by the die change cylinders 92 off of the rollers 81 provided on the upper surface of the die transfer housing 80 and onto the upper surface of the crosshead 70, as shown in Fig. 6.
- This lateral movement of the hydroforming die is accomplished by the die change cylinders 92 that, as mentioned above, are secured to the backing plate 45 or otherwise supported on the hydroforming apparatus 10.
- the die change cylinders 92 are adapted to engage portions of the lower die mounting plate 85 or other portions of the hydroforming die to selectively effect lateral movement thereof. When so moved, the hydroforming die is vertically aligned between the upper die clamping assemblies 50 and 51 carried on the upper platen 20.
- the lift cylinders 71 are again actuated as shown in Fig. 7 to extend the pistons 71a, thereby elevating the crosshead 70 and the hydroforming die to a further elevated position.
- the upper surface of the upper die mounting plate 82 abuts the lower surface of the retainer plate 60.
- the recesses 82a and 82b formed in the upper die mounting plate 82 are laterally aligned with the retracted locking pins 52a and 53a provided on the die locking cylinders 52 and 53, respectively.
- the die locking cylinders 52 and 53 are actuated to move the locking pins 52a and 53a, respectively from their retracted positions to the extended positions illustrated in Fig. 7.
- the locking pins 52a and 53a are respectively received within the recesses 82a and 83a formed in the upper die mounting plate 82. Consequently, the upper die mounting plate 82, and the upper die section 83 secured thereto, are positively connected to the upper die clamping assemblies 50 and 51 and, therefore, the upper platen 20.
- the recesses 82a and 82b formed in the upper die mounting plate 82 are somewhat larger in size, at least in the vertical direction, than the locking pins 52a and 53a.
- the upper die mounting plate 82 and the upper die section 83 are supported on the upper die clamping assemblies 50 and 51 for limited upward and downward movement.
- Fig. 8 The final steps in the die installation process are shown in Fig. 8. Initially, the spacer block cylinders 76 are actuated to retract the die change spacer block 75 laterally from beneath the crosshead 70 to its original position. Then, the pistons 71a of the lift cylinders 71 are retracted to lower the lower die section 84, the lower die mounting plate 85, and the crosshead 70 relative to the upper die mounting plate 82 and the upper die section 83, which remain connected to the upper die clamping assemblies 50 and 51 and the upper platen 20. This completes the die installation process for the hydroforming apparatus 10, which is now ready to perform a hydroforming operation.
- the initial step in the cycle of the hydroforming operation is also shown in Fig. 8, wherein a workpiece 93 is inserted between the upper and lower die sections 82 and 83, respectively. Because the lower die section 84 has been lowered relative to the upper die section 83, clearance is provided to insert the workpiece 93 therebetween.
- the workpiece 93 is a closed channel structural member, such as a tubular member, that may be pre-bent in a known manner to achieve a predetermined rough shape for the final hydroformed component. Any conventional mechanism (not shown) can be used to insert the workpiece 93 between the upper die section 83 and the lower die section 84. Typically, the workpiece 93 will be placed within the recessed area 84a formed in the lower die section 84.
- the workpiece 93 is preferably sized such that the ends thereof extend a predetermined distance transversely from each side of the hydroforming die. This is done to facilitate the connection of conventional end feed cylinders (not shown) thereto to perform the hydroforming process, as will be explained in further detail below.
- the pistons 71a of the lift cylinders 71 and the pistons 72a of the crush cylinders 72 are actuated to elevate the lower die section 84, the lower die mounting plate 85, and the crosshead 70 upwardly relative to the upper die mounting plate 82 and the upper die section 83 to an uppermost position shown in Fig. 9.
- the lift cylinders 71 are preferably relatively small in size so as to selectively effect relatively high velocity, low force exertion movement of the pistons 71a.
- the majority of the elevation of the lower die section 84, the lower die mounting plate 85, and the crosshead 70 can be performed relatively quickly, which advantageously reduces the overall cycle time of the hydroforming apparatus.
- the crush cylinders 72 are preferably relatively large in size so as to selectively effect relatively low velocity, high force exertion movement of the pistons 72a.
- the pistons 72a of the crush cylinders 72 may follow slightly behind the pistons 71a of the lift cylinders 71.
- the pistons 72a of the crush cylinders 72 bear no load during this upward movement, the amount of lag time required for the pistons 72a of the crush cylinders 72 to catch up with the pistons 71a of the lift cylinders 71 is minimal.
- the support block cylinders 91 can then be actuated to extend the support block 90 laterally beneath the crosshead 70, as shown in Fig. 10.
- one or more slots 90a are formed in the support block 90. These slots 90a are provided to permit this lateral movement of the support block 90 to occur while the pistons 71a of the lift cylinders 71 and the pistons 72a of the crush cylinders 72 are extended. Such pistons 71a and 72a are received within the clearance provided by the slots 90a so that no interference with the support block 90 occurs.
- the pistons 71a of the lift cylinders 71 and the pistons 72a of the crush cylinders 72 are retracted such that the lower surface of the crosshead 70 is lowered onto the upper surface of the hydroforming support block 90, as shown in Fig. 11.
- the entire hydroforming die is positively supported on the hydroforming support block 90 and, therefore, the lower platen 30 of the hydroforming apparatus 10.
- the passageways 57 formed through the cylinder array 54 are placed in fluid communication with the source of pressurized fluid.
- the pressurized fluid causes the pistons 56 contained within the cylinder array 54 to be extend outwardly from their respective cylinders 55, exerting a relatively large downward force against the retainer plate and the upper die mounting plate 82.
- the compression tubes 40 are pre-stressed with compressive forces by the tie rods 43 and the nuts 44. Because of the engagement of the upper plate 20 with the backing plate, the reaction forces generated during the hydroforming operation tend to generate tension forces in the compression tubes 40.
- the pre-stressed compressive forces generated in the compression tubes 40 are predetermined to be approximately equal to or slightly greater than the maximum amount of such tension forces generated during the hydroforming operation. As a result, such tension forces tend to counteract the pre-stressed compressive forces in the compression tubes 40, as opposed to generating net tension forces in the compression tubes 40.
- the passageways 57 formed through the cylinder array 54 are removed from fluid communication with the source of pressurized fluid, thereby releasing the relatively large clamping forces exerted against the hydroforming die.
- the pistons 71a of the lift cylinders 71 are extended to elevate the crosshead 70 above the spacer block 90, as shown in Fig. 10.
- the support block cylinders 91 can then be actuated to retract the support block 90 within the hydroforming support block 90, as shown in Fig. 9.
- the installation of the hydroforming die and the cycle of the hydroforming operation entails a series of sequential operations of the various components of the hydroforming apparatus 10.
- a plurality of sensors are preferably provided on the hydroforming apparatus 10.
- Such sensors are conventional in the art and are adapted to generate electrical signals that are representative of various operating conditions of the hydroforming apparatus 10.
- the sensed operating conditions can include position sensors to insure that the moving components of the hydroforming apparatus 10 actually achieve their desired positions before proceeding with the next step in the cycle of the hydroforming operation, pressure sensors to insure that proper pressurization is achieved within the cylinder array 54, and the like.
- the signals from such sensors can be fed to one or more electronic controllers (not shown) for actuating the various components of the hydroforming apparatus 10.
- the electronic controllers are conventional in the art and can be programmed to monitor the signals from the various sensors and, in response thereto, cause the sequential operations set forth above to be performed.
- the structure and operation of the sensors and the electronic controllers is within the knowledge of a person having ordinary skill in the art.
Landscapes
- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Physics & Mathematics (AREA)
- Fluid Mechanics (AREA)
- Shaping Metal By Deep-Drawing, Or The Like (AREA)
- Forging (AREA)
- Press Drives And Press Lines (AREA)
Abstract
Description
- This invention relates in general to an apparatus for performing a hydroforming operation on a closed channel workpiece. In particular, this invention relates to an improved structure for such a hydroforming apparatus that is relative simple and inexpensive in structure and operation and is well suited for performing a hydroforming operation on relatively long workpieces, such as side rails for a vehicle frame assembly.
- Hydroforming is a well known metal working process that uses pressurized fluid to deform a closed channel workpiece, such as a tubular member, outwardly into conformance with a die cavity having a desired shape. A typical hydroforming apparatus includes a frame having a two or more die sections that are supported thereon for relative movement between opened and closed positions. The die sections have cooperating recesses formed therein that together define a die cavity having a shape corresponding to a desired final shape for the workpiece. When moved to the opened position, the die sections are spaced apart from one another to allow a workpiece to be inserted within or removed from the die cavity. When moved to the closed position, the die sections are disposed adjacent to one another so as to enclose the workpiece within the die cavity. Although the die cavity is usually somewhat larger than the workpiece to be hydroformed, movement of the two die sections from the opened position to the closed position may, in some instances, cause some mechanical deformation of the hollow member. In any event, the workpiece is then filled with a fluid, typically a relatively incompressible liquid such as water. The pressure of the fluid within the workpiece is increased to such a magnitude that the workpiece is expanded outwardly into conformance with the die cavity. As a result, the workpiece is deformed or expanded into the desired final shape. Hydroforming is an advantageous process for forming vehicle frame components and other structures because it can quickly deform a workpiece into a desired complex shape.
- In a typical hydroforming apparatus, the die sections are arranged such that an upper die section is supported on a ram of the apparatus, while a lower die section is supported on a bed of the apparatus. A mechanical or hydraulic actuator is provided for raising the ram and the upper die section upwardly to the opened position relative to the lower die section, allowing the previously deformed workpiece to be removed from and the new workpiece to be inserted within the die cavity. The actuator also lowers the ram and the upper die section downwardly to the closed position relative to the lower die section, allowing the hydroforming process to be performed. To maintain the die sections together during the hydroforming process, a mechanical clamping device is usually provided. The mechanical clamping device mechanically engages the die sections (or, alternatively, the ram and the base upon which the die sections are supported) to prevent them from moving apart from one another during the hydroforming process. Such movement would obviously be undesirable because the shape of the die cavity would become distorted, resulting in unacceptable variations in the final shape of the workpiece.
- As mentioned above, the hydroforming process involves the application of a highly pressurized fluid within the workpiece to cause expansion thereof. The magnitude of the pressure of the fluid within the workpiece will vary according to many factors, one of which being the physical size of the workpiece to be deformed. When a relatively small or thin-walled workpiece is being deformed, the magnitude of the pressure of the fluid supplied within the workpiece during the hydroforming operation is relatively small. Accordingly, the amount of the outwardly-directed force exerted by the workpiece on the die sections during the hydroforming operation is also relatively small. In these instances, only a relatively small amount of inwardly-directed force is required to be exerted by the hydroforming apparatus to counteract the outwardly-directed force so as to maintain the die sections in the closed position during the hydroforming operation. Consequently, the physical size and strength of the hydroforming apparatus when used for deforming relatively small or thin-walled workpieces is no greater than a typical mechanical press for performing a similar operation.
- However, when a relatively large or thick-walled workpiece is being deformed (such as is found in many vehicle frame components, including side rails, cross members, and the like), the magnitude of the pressure of the fluid supplied within the workpiece during the hydroforming operation is relatively large. Accordingly, the amount of the outwardly-directed force exerted by the workpiece on the die sections during the hydroforming operation is also relatively large. To counteract this, a relatively large amount of inwardly-directed force is required to be exerted by the hydroforming apparatus to maintain the die sections in the closed position during the hydroforming operation. Consequently, the physical size and strength of the hydroforming apparatus is as large or larger than a typical mechanical press for performing a similar operation. This is particularly troublesome when the workpiece is relatively long, such as found in side rails for vehicle frames. The cost and complexity of manufacturing a conventional hydroforming apparatus that is capable of deforming such a workpiece is very high. Thus, it would be desirable to provide an improved structure for a hydroforming apparatus that is capable of deforming relatively large and thick-walled workpieces, yet which is relatively small, simple, and inexpensive in construction and operation.
- This invention relates to an improved structure for a hydroforming apparatus that is capable of deforming relatively large and thick-walled workpieces, yet which is relatively small, simple, and inexpensive in construction and operation. The hydroforming apparatus includes an upper platen and a lower platen that are connected together by tie rods extending through respective compression tubes. An upper die section is supported on the upper platen, while a lower die section is supported on the lower platen for vertical movement relative to the upper die section. The upper and lower die sections have respective recessed areas formed therein that define a hydroforming die cavity. When the lower die section is moved to a lowered position, a workpiece can be disposed in the recessed area formed therein. Then, the lower die section and the workpiece are elevated by cylinders such that the workpiece is enclosed within the hydroforming cavity and mechanically deformed by the cooperated upper and lower die sections. A hydroforming support block is then moved between the hydroforming die and the lower platen. A cylinder array containing a plurality of pistons is next hydraulically actuated so as to securely clamp the hydroforming die between the cylinder array and the support block. While the cylinder array is actuated, pressurized fluid is supplied within the workpiece, causing it to deform into conformance with the hydroforming die cavity.
- Various objects and advantages of this invention will become apparent to those skilled in the art from the following detailed description of the preferred embodiment, when read in light of the accompanying drawings.
-
- Fig. 1 is a front elevational view of a portion of a hydroforming apparatus in accordance with this invention.
- Fig. 2 is a sectional elevational view, partially broken away, of the hydroforming apparatus illustrated in Fig. 1 showing the components thereof prior to the installation of a hydroforming die within the hydroforming apparatus.
- Fig. 3 is an enlarged perspective view, partially broken away, of a portion of the hydroforming apparatus illustrated in Figs. 1 and 2.
- Fig. 4 is a sectional elevational view similar to Fig. 2 showing the crosshead after having been raised to an elevated position by the lift cylinders.
- Fig. 5 is a sectional elevational view similar to Fig. 4 showing the die change spacer block after having been moved to an extended position beneath the crosshead by the spacer block cylinders.
- Fig. 6 is a sectional elevational view similar to Fig. 5 showing the crosshead after having been lowered onto the die change spacer block by the lift cylinders, and the hydroforming die after having been moved onto the crosshead by the die change cylinders.
- Fig. 7 is a sectional elevational view similar to Fig. 6 showing the crosshead and the hydroforming die after having been moved to a further elevated position by the lift cylinders, and the upper die section after having been secured to the upper die clamping assemblies.
- Fig. 8 is a sectional elevational view similar to Fig. 7 showing the die change spacer block after having been moved to a retracted position by the spacer block cylinders, the crosshead and the lower die section after having been lowered relative to the upper die section by the lift cylinders, and a workpiece after having been inserted within the hydroforming die.
- Fig. 9 is a sectional elevational view similar to Fig. 8 showing the crosshead and the hydroforming die after having been moved to the furthermost elevated position by the lift cylinders and the crush cylinders.
- Fig. 10 is a sectional elevational view similar to Fig. 9 showing the hydroforming support block after having been moved to an extended position beneath the crosshead and the hydroforming die by the support block cylinders.
- Fig. 11 is a sectional elevational view similar to Fig. 10 showing the pistons contained in the cylinder array after having been extended downwardly by pressurized fluid during the hydroforming operation.
-
- Referring now to the drawings, there is illustrated in Figs. 1 and 2 a hydroforming apparatus, indicated generally at 10, in accordance with this invention. The illustrated
hydroforming apparatus 10 is of generally modular construction, including three hydroforming modules indicated at 11, 12, and 13. Themodules such hydroforming modules hydroforming apparatus 10 may be formed having a greater or lesser number ofsuch modules hydroforming apparatus 10 need not be formed having such a modular construction. - Each of the
modules hydroforming apparatus 10 includes an upper platen, indicated generally at 20. The illustratedupper platen 20 is generally box-shaped in construction, including an upper horizontally extendingstructural plate 21, a lower horizontally extendingstructural plate 22, a front vertically extendingstructural plate 23, and a rear vertically extendingstructural plate 24. Thestructural plates front reinforcement plates 25 and a second pair of laterally extending rear reinforcement plates 26 (only one is illustrated) can be connected to thestructural plates upper platen 20. - Each of the
modules hydroforming apparatus 10 also includes a lower platen, indicated generally at 30. The illustratedlower platen 30 is also generally box-shaped in construction, including an upper horizontally extendingstructural plate 31, a lower horizontally extendingstructural plate 32, a front vertically extendingstructural plate 33, and a rear vertically extendingstructural plate 34. Thestructural plates structural plates lower platen 30. - The
upper platen 20 and thelower platen 30 are connected together by a pair of vertically extending compression tubes ormembers compression tubes lower ends compression tubes upper platen 20 and thelower platen 30 in any conventional manner, such as by welding. If desired, a transversely extending supporting plate 42 (see Fig. 1) may be connected between thecompression tubes compression tubes hydroforming apparatus 10 as a whole. - A
tie rod 43 extends through each of thecompression tubes upper platen 20 to thelower platen 30. Each of thetie rods 43 is a generally solid cylindrical member having anupper end portion 43a that extends above the upper horizontally extendingstructural plate 21 of theupper platen 20 and alower end portion 43b that extends below the lower horizontally extendingstructural plate 32 of thelower platen 30. In the illustrated embodiment, the upper andlower end portions tie rod 43 are threaded, andnuts 44 or similar retaining devices are threaded onto such threadedend portions tie rods 43 to thecompression tubes 41. When tightened, the nuts 44 are drawn into engagement with the upper horizontally extendingstructural plate 21 of theupper platen 20 and the lower horizontally extendingstructural plate 32 of thelower platen 30, as well as the upper andlower end portions compression tubes 40. As a result, thecompression tubes 40 are pre-stressed with compressive forces, for a purpose that will be explained below. If desired, structures other than the illustrated threadedend portions nuts 44 may be used for accomplishing these purposes. Abacking plate 45 extends between the lower horizontally extendingstructural plate 22 of theupper platen 20 and the upper horizontally extendingstructural plate 31 of thelower platen 30 for a purpose that will also be explained below. - A pair of upper
die clamping assemblies upper platen 20. In the illustrated embodiment, the upperdie clamping assemblies structural plate 22 of theupper platen 20 in any conventional manner, such as by welding. The upperdie clamping assemblies die locking cylinders die locking cylinders die locking cylinders die clamping assemblies - A
cylinder array 54 is also provided on theupper platen 20. In the illustrated embodiment, thecylinder array 54 is secured to the lower horizontally extendingstructural plate 22 of theupper platen 20 in any conventional manner, such as by welding, and extends laterally between upperdie clamping assemblies cylinder array 54 has a plurality ofhollow cylinders 55 formed in the lower surface thereof. The quantity and location of suchhollow cylinders 55 may be determined as necessary to perform the hydroforming operation described below. Apiston 56 is disposed in each of thehollow cylinders 55 for limited upward and downward movement in the manner described below. A plurality ofpassageways 57 are formed through thecylinder array 54 such that thehollow cylinders 55 are in fluid communication with one another. Thepassageways 57 selectively communicate with a source of pressurized fluid (not shown). The purpose for thecylinder array 54 and thepistons 56 will be explained below. - A
retainer plate 60 is provided on thecylinder array 54 for retaining thepistons 56 within thecylinders 55. Theretainer plate 60 is supported on thecylinder array 54 for limited upward and downward movement by a plurality of support assemblies, indicated generally at 61. In the illustrated embodiment, a first pair ofsupport assemblies 61 are provided on the front side of thecylinder array 54, and a second pair of support assemblies (not shown) are provided on the rear side of thecylinder array 54. However, any number ofsuch support assemblies 61 may be provided at any desired locations. The structure of one of thesupport assemblies 61 is illustrated in detail in Fig. 3. As shown therein, thesupport assembly 61 includes abacking plate 62 having a pair ofupstanding ears 63 formed thereon or secured thereto. Each of theears 63 has anopening 63a formed therethrough, and theopenings 63a are vertically aligned with one another. Arod 64 extends through the alignedopenings 63a formed through theears 63 for vertical sliding movement relative thereto. Therod 64 has a lower end that is secured to alug 60a formed on or secured to theretainer plate 60 for movement therewith. Therod 64 further has an upper end that has anenlarged nut 65 or other retaining device formed thereon or secured thereto. Thenut 65 is larger in size than theopenings 63a formed through theears 63. Thus, theretainer plate 60 and therods 64 can move upwardly and downwardly relative to thecylinder array 54 between an uppermost position, wherein theretainer plate 60 abuts thecylinder array 54, and a lowermost position, wherein thenut 65 engages the upper surface of theupper ear 63. The purpose for this limited relative movement will be explained below. - A
crosshead 70 is supported on the upper horizontally extendingstructural plate 31 of thelower platen 30. Thecrosshead 70 is supported for limited vertical movement relative to the upper horizontally extendingstructural plate 31 by one or more lift cylinders 71 (two of which are illustrated in Fig. 2) and one or more crush cylinders 72 (one of which is illustrated in Fig. 2). Thelift cylinders 71 are secured to the upper horizontally extendingstructural plate 31 or are otherwise supported on thelower platen 30. Each of thelift cylinders 71 has apiston 71a that extends upwardly therefrom through an opening formed through the upper horizontally extendingstructural plate 31 and is adapted to engage the lower surface of thecrosshead 70. Thelift cylinders 71 are preferably relatively small in size so as to selectively effect relatively high velocity, low force exertion movement of thepistons 71a and thecrosshead 70. Thelift cylinders 71 are preferably hydraulically actuated, although such is not necessary. Thecrush cylinders 72 are also secured to the upper horizontally extendingstructural plate 31 or are otherwise supported on thelower platen 30. Each of thecrush cylinders 72 has apiston 72a that extends upwardly therefrom through an opening formed through the upper horizontally extendingstructural plate 31 and is adapted to engage the lower surface of thecrosshead 70. Thecrush cylinders 72 are preferably relatively large in size so as to selectively effect relatively low velocity, high force exertion movement of thepistons 71a and thecrosshead 70. Thecrush cylinders 72 are also preferably hydraulically actuated, although such is not necessary. The quantity and location ofsuch lift cylinders 71 andcrush cylinders 72 may be determined as necessary to perform the hydroforming operation described below. - A die
change spacer block 75 is supported on the upper horizontally extendingstructural plate 31 of thelower platen 30. The diechange spacer block 75 is supported for limited horizontal movement relative to the upper horizontally extendingstructural plate 31 by one or morespacer block cylinders 76 that may be supported on the upper horizontally extendingstructural plate 31 of thelower platen 30. Thus, the diechange spacer block 75 can be moved between a retracted position (illustrated in Fig. 2) and an extended position by thespacer block cylinders 76. One ormore slots 75a are formed in the diechange spacer block 75. The purpose for the diechange spacer block 75 and theslots 75a will be explained below. - A hollow
die transfer housing 80 is connected to the upper horizontally extendingstructural plate 31 or otherwise supported on thelower platen 30. As shown in Fig. 1, the illustrateddie transfer housing 80 extends laterally throughout all of thehydroforming modules hydroforming apparatus 10, although such is not necessary. Thedie transfer housing 80 has a plurality ofrollers 81 or other transport mechanisms provided on the upper surface thereof. A hydroforming die, including an upperdie mounting plate 82, anupper die section 83, alower die section 84, and a lowerdie mounting plate 85, is supported on therollers 81 of thedie transfer housing 80. The upper surface of theupper die section 83 is secured to the upperdie mounting plate 82, while the lower surface of the-upper die section 83 has a recessedarea 83a formed therein. Similarly, the lower surface of thelower die section 84 is secured to the lowerdie mounting plate 85, while the upper surface of thelower die section 84 has a recessedarea 84a formed therein. When the upper and lower diesections areas die mounting plate 82 hasrecesses recesses - A
hydroforming support block 90 is supported within the hollowdie transfer housing 80. Thehydroforming support block 90 is supported for limited horizontal movement relative to thedie transfer housing 80 by one or moresupport block cylinders 91 that may be provided within thedie transfer housing 80 or supported in any other desired location on thehydroforming apparatus 10. Thus, thehydroforming support block 90 can be moved between a retracted position (illustrated in Fig. 2) and an extended position by thesupport block cylinders 91. One ormore slots 90a are formed in thehydroforming support block 90. The purpose for thehydroforming support block 90 and theslots 90a will be explained below. Referring back to Fig. 1, a pair ofdie change cylinders 92 are secured to thebacking plate 45 or otherwise supported on thehydroforming apparatus 10. The purpose for thedie change cylinders 92 will be explained below. - The operation of the
hydroforming apparatus 10 will now be described. Initially, the hydroforming die must be installed within thehydroforming apparatus 10. To accomplish this, the various components of thehydroforming apparatus 10 are oriented in the retracted positions illustrated in Fig. 2, and the hydroforming die is disposed on top of therollers 81 provided on the upper surface of thedie transfer housing 80. In this initial arrangement, thepassageways 57 formed through thecylinder array 54 do not communicate with the source of pressurized fluid. Thus, although thepistons 56 and theretainer plate 60 depend from thecylinder array 60 under the influence of gravity to the extent permitted by thesupport assemblies 61, no pressure is exerted thereby. - To install the hydroforming die within the
hydroforming apparatus 10, thelift cylinders 71 are initially actuated as shown in Fig. 4 to extend thepistons 71a, thereby elevating thecrosshead 70 to an elevated position. In this elevated position, the upper surface of thecrosshead 70 is disposed somewhat higher than the lower surface of the hydroforming die supported on therollers 81 provided on the upper surface of thedie transfer housing 80. At the same time, the lower surface of thecrosshead 70 is disposed somewhat higher than the upper surface of the diechange spacer block 75. - Then, as shown in Fig. 5, the
spacer block cylinders 76 are actuated to extend the diechange spacer block 75 laterally beneath thecrosshead 70. As mentioned above, one ormore slots 75a are formed in the diechange spacer block 75. Theseslots 75a are provided to permit this lateral movement of the diechange spacer block 75 to occur while thepistons 71a of thelift cylinders 71 are extended.Such pistons 71a are received within the clearance provided by theslots 75a so that no interference with the diechange spacer block 75 occurs. Thereafter, thepistons 71a of thelift cylinders 71 are retracted such that thecrosshead 70 is lowered onto the diechange spacer block 75, as also shown in Fig. 5. Thecrosshead 70 and the diechange spacer block 75 are sized such that when thecrosshead 70 is lowered onto the diechange spacer block 75, the upper surface of thecrosshead 70 is precisely flush with the lower surface of the hydroforming die disposed on top of therollers 81 provided on the upper surface of thedie transfer housing 80. - As a result of this flush alignment, the hydroforming die can be moved laterally by the
die change cylinders 92 off of therollers 81 provided on the upper surface of thedie transfer housing 80 and onto the upper surface of thecrosshead 70, as shown in Fig. 6. This lateral movement of the hydroforming die is accomplished by thedie change cylinders 92 that, as mentioned above, are secured to thebacking plate 45 or otherwise supported on thehydroforming apparatus 10. Thedie change cylinders 92 are adapted to engage portions of the lowerdie mounting plate 85 or other portions of the hydroforming die to selectively effect lateral movement thereof. When so moved, the hydroforming die is vertically aligned between the upperdie clamping assemblies upper platen 20. - Next, the
lift cylinders 71 are again actuated as shown in Fig. 7 to extend thepistons 71a, thereby elevating thecrosshead 70 and the hydroforming die to a further elevated position. In this further elevated position, the upper surface of the upperdie mounting plate 82 abuts the lower surface of theretainer plate 60. At the same time, therecesses die mounting plate 82 are laterally aligned with the retractedlocking pins die locking cylinders die locking cylinders recesses die mounting plate 82. Consequently, the upperdie mounting plate 82, and theupper die section 83 secured thereto, are positively connected to the upperdie clamping assemblies upper platen 20. As is apparent in Fig. 7, therecesses die mounting plate 82 are somewhat larger in size, at least in the vertical direction, than the locking pins 52a and 53a. Thus, similar to theretainer plate 60, the upperdie mounting plate 82 and theupper die section 83 are supported on the upperdie clamping assemblies - The final steps in the die installation process are shown in Fig. 8. Initially, the
spacer block cylinders 76 are actuated to retract the diechange spacer block 75 laterally from beneath thecrosshead 70 to its original position. Then, thepistons 71a of thelift cylinders 71 are retracted to lower thelower die section 84, the lowerdie mounting plate 85, and thecrosshead 70 relative to the upperdie mounting plate 82 and theupper die section 83, which remain connected to the upperdie clamping assemblies upper platen 20. This completes the die installation process for thehydroforming apparatus 10, which is now ready to perform a hydroforming operation. - The initial step in the cycle of the hydroforming operation is also shown in Fig. 8, wherein a
workpiece 93 is inserted between the upper and lower diesections lower die section 84 has been lowered relative to theupper die section 83, clearance is provided to insert theworkpiece 93 therebetween. Theworkpiece 93 is a closed channel structural member, such as a tubular member, that may be pre-bent in a known manner to achieve a predetermined rough shape for the final hydroformed component. Any conventional mechanism (not shown) can be used to insert theworkpiece 93 between theupper die section 83 and thelower die section 84. Typically, theworkpiece 93 will be placed within the recessedarea 84a formed in thelower die section 84. Theworkpiece 93 is preferably sized such that the ends thereof extend a predetermined distance transversely from each side of the hydroforming die. This is done to facilitate the connection of conventional end feed cylinders (not shown) thereto to perform the hydroforming process, as will be explained in further detail below. - Next, the
pistons 71a of thelift cylinders 71 and thepistons 72a of thecrush cylinders 72 are actuated to elevate thelower die section 84, the lowerdie mounting plate 85, and thecrosshead 70 upwardly relative to the upperdie mounting plate 82 and theupper die section 83 to an uppermost position shown in Fig. 9. As mentioned above, thelift cylinders 71 are preferably relatively small in size so as to selectively effect relatively high velocity, low force exertion movement of thepistons 71a. As a result, the majority of the elevation of thelower die section 84, the lowerdie mounting plate 85, and thecrosshead 70 can be performed relatively quickly, which advantageously reduces the overall cycle time of the hydroforming apparatus. As also mentioned above, thecrush cylinders 72 are preferably relatively large in size so as to selectively effect relatively low velocity, high force exertion movement of thepistons 72a. Thus, during this initial elevation of thelower die section 84, the lowerdie mounting plate 85, and thecrosshead 70, thepistons 72a of thecrush cylinders 72 may follow slightly behind thepistons 71a of thelift cylinders 71. However, because thepistons 72a of thecrush cylinders 72 bear no load during this upward movement, the amount of lag time required for thepistons 72a of thecrush cylinders 72 to catch up with thepistons 71a of thelift cylinders 71 is minimal. - When the
pistons 72a of thecrush cylinders 72 do catch up, they engage and exert a relatively large amount of force against the lower surface of thecrosshead 70. As a result, the lowerdie mounting plate 85 and thelower die 84 are urged upwardly against theupper die 83 and the upperdie mounting plate 82 with a relatively large amount of force. Such force also urges theretainer plate 60 upwardly into engagement with thecylinder array 54, as shown in Fig. 9. During this movement, thepistons 56 are retracted within theirrespective cylinders 55. As mentioned above, thepassageways 57 formed through thecylinder array 54 do not communicate with the source of pressurized fluid. Thus, only the force of gravity must be overcome to move theretainer plate 60 upwardly into engagement with thecylinder array 54, and to retract thepistons 56 within theirrespective cylinders 55. The relatively large force exerted by thecrush cylinders 72 may cause portions of theworkpiece 93 to be mechanically deformed by the upper and lower diesections - When the
lower die section 84, the lowerdie mounting plate 85, and thecrosshead 70 have been moved upwardly relative to the upperdie mounting plate 82 and theupper die section 83 to the uppermost position shown in Fig. 9, the lower surface of thecrosshead 70 is positioned slightly above the upper surface of thehydroforming support block 90 disposed within the hollowdie transfer housing 80. Accordingly, thesupport block cylinders 91 can then be actuated to extend thesupport block 90 laterally beneath thecrosshead 70, as shown in Fig. 10. As mentioned above, one ormore slots 90a are formed in thesupport block 90. Theseslots 90a are provided to permit this lateral movement of thesupport block 90 to occur while thepistons 71a of thelift cylinders 71 and thepistons 72a of thecrush cylinders 72 are extended.Such pistons slots 90a so that no interference with thesupport block 90 occurs. - Then, the
pistons 71a of thelift cylinders 71 and thepistons 72a of thecrush cylinders 72 are retracted such that the lower surface of thecrosshead 70 is lowered onto the upper surface of thehydroforming support block 90, as shown in Fig. 11. As a result, the entire hydroforming die is positively supported on thehydroforming support block 90 and, therefore, thelower platen 30 of thehydroforming apparatus 10. Thereafter, thepassageways 57 formed through thecylinder array 54 are placed in fluid communication with the source of pressurized fluid. The pressurized fluid causes thepistons 56 contained within thecylinder array 54 to be extend outwardly from theirrespective cylinders 55, exerting a relatively large downward force against the retainer plate and the upperdie mounting plate 82. - In this manner, the hydroforming die is securely clamped together, allowing the hydroforming operation to occur. As mentioned above, conventional end feed cylinders (not shown) engage the ends of the
workpiece 93 that protrude from the sides of the hydroforming die. Such end feed cylinders seal against the ends of theworkpiece 93 and provide a mechanism for supplying pressurized fluid to the interior of theworkpiece 93. In a manner that is well known in the art, such pressurized fluid causes theworkpiece 93 to deform or expand outwardly into conformance with the die cavity defined by the upper and lower diesections pistons 56 against the retainer plate and the upperdie mounting plate 82, and further because the lowerdie mounting plate 85 and thecrosshead 70 are positively supported on thehydroforming support block 90 and thelower platen 30 of thehydroforming apparatus 10, relative movement between theupper die section 83 and thelower die section 84 during the pressurization of theworkpiece 93 is prevented. - It will be appreciated that during the hydroforming operation, relatively large reaction forces are generated against the front ends of the upper and
lower platens hydroforming apparatus 10. When viewing Fig. 11, it can be seen that such reaction forces tend to tilt theupper platen 20 in a clockwise direction about thetie rods 43 relative to thelower platen 30. Such reaction forces are, in large measure, absorbed by thebacking plate 45 that extends between the rear ends of the upper andlower platens tie rods 43 forwardly to the center of the hydroforming die (which is where the reaction forces are generated) is much smaller that the lateral distance from the centers of thetie rods 43 rearwardly to the backing plate 45 (which is where the reaction forces are absorbed). The mechanical advantage provided by the difference in distances allows the size of thebacking plate 45 to be maintained relatively small. Thus, the overall size, weight, and expense of thehydroforming apparatus 10 is minimized. - Also, as mentioned above, the
compression tubes 40 are pre-stressed with compressive forces by thetie rods 43 and the nuts 44. Because of the engagement of theupper plate 20 with the backing plate, the reaction forces generated during the hydroforming operation tend to generate tension forces in thecompression tubes 40. Preferably, the pre-stressed compressive forces generated in thecompression tubes 40 are predetermined to be approximately equal to or slightly greater than the maximum amount of such tension forces generated during the hydroforming operation. As a result, such tension forces tend to counteract the pre-stressed compressive forces in thecompression tubes 40, as opposed to generating net tension forces in thecompression tubes 40. - At the conclusion of the hydroforming of the
workpiece 93, thepassageways 57 formed through thecylinder array 54 are removed from fluid communication with the source of pressurized fluid, thereby releasing the relatively large clamping forces exerted against the hydroforming die. At the same time, thepistons 71a of thelift cylinders 71 are extended to elevate thecrosshead 70 above thespacer block 90, as shown in Fig. 10. Thesupport block cylinders 91 can then be actuated to retract thesupport block 90 within thehydroforming support block 90, as shown in Fig. 9. Lastly, thepistons 71a of thelift cylinders 71 are retracted to lower thecrosshead 70, the lowerdie mounting plate 85, and thelower die section 84 downwardly relative to theupper die section 83 and the upperdie mounting plate 82, as shown in Fig. 8. Thehydroformed workpiece 93 can then be removed to complete the cycle of the hydroforming operation. - As described above, the installation of the hydroforming die and the cycle of the hydroforming operation entails a series of sequential operations of the various components of the
hydroforming apparatus 10. To accomplish these sequential operations quickly and safely, a plurality of sensors (not shown) are preferably provided on thehydroforming apparatus 10. Such sensors are conventional in the art and are adapted to generate electrical signals that are representative of various operating conditions of thehydroforming apparatus 10. The sensed operating conditions can include position sensors to insure that the moving components of thehydroforming apparatus 10 actually achieve their desired positions before proceeding with the next step in the cycle of the hydroforming operation, pressure sensors to insure that proper pressurization is achieved within thecylinder array 54, and the like. The signals from such sensors can be fed to one or more electronic controllers (not shown) for actuating the various components of thehydroforming apparatus 10. The electronic controllers are conventional in the art and can be programmed to monitor the signals from the various sensors and, in response thereto, cause the sequential operations set forth above to be performed. The structure and operation of the sensors and the electronic controllers is within the knowledge of a person having ordinary skill in the art. - In accordance with the provisions of the patent statutes, the principle and mode of operation of this invention have been explained and illustrated in its preferred embodiment. However, it must be understood that this invention may be practiced otherwise than as specifically explained and illustrated without departing from its spirit or scope.
Claims (1)
- An apparatus for performing a hydroforming operation comprising:an upper platen having a first end and a second end;a lower platen having a first end and a second end;a member extending between said first and second ends of said upper platen and between said first and second ends of said lower platen;a hydroforming die disposed between said first end of said upper platen and said first end of said lower platen; anda backing plate extending between said second end of said upper platen and said second end of said lower platen.
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US53936400A | 2000-03-31 | 2000-03-31 | |
US539364 | 2000-03-31 |
Publications (3)
Publication Number | Publication Date |
---|---|
EP1138410A2 true EP1138410A2 (en) | 2001-10-04 |
EP1138410A3 EP1138410A3 (en) | 2002-05-08 |
EP1138410B1 EP1138410B1 (en) | 2004-11-10 |
Family
ID=24150909
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
EP20010302975 Expired - Lifetime EP1138410B1 (en) | 2000-03-31 | 2001-03-29 | Apparatus for performing a hydroforming operation |
Country Status (5)
Country | Link |
---|---|
EP (1) | EP1138410B1 (en) |
AR (1) | AR034846A1 (en) |
BR (1) | BR0101259A (en) |
DE (1) | DE60106999T2 (en) |
MX (1) | MXPA01003415A (en) |
Families Citing this family (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN104339185A (en) * | 2013-08-07 | 2015-02-11 | 江苏博俊工业科技股份有限公司 | Sectional machining structure of large stamping die set |
Citations (7)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3247783A (en) * | 1964-05-21 | 1966-04-26 | Erie Foundry Company | Hydraulic press |
FR1595056A (en) * | 1968-12-12 | 1970-06-08 | ||
GB1318183A (en) * | 1969-04-25 | 1973-05-23 | Skelcher H G | Presses for cutting or forming metal or other materials |
DE2528153A1 (en) * | 1975-06-24 | 1977-03-31 | Seiji Shiokawa | Single column hydraulic press - has corrective control device to counteract inaccuracies caused by frame flexure |
EP0686440A1 (en) * | 1994-05-12 | 1995-12-13 | Benteler Industries, Inc. | Hydroforming apparatus |
US5482454A (en) * | 1992-01-31 | 1996-01-09 | Nissei Plastic Industrial Co., Ltd. | C-type frame for die tightening units mounted for an injection molding machine |
US6018971A (en) * | 1998-03-06 | 2000-02-01 | Bentler Ag | Apparatus for hydraulically shaping hollow bodies of metal |
-
2001
- 2001-03-29 DE DE2001606999 patent/DE60106999T2/en not_active Expired - Lifetime
- 2001-03-29 EP EP20010302975 patent/EP1138410B1/en not_active Expired - Lifetime
- 2001-03-30 AR ARP010101571 patent/AR034846A1/en active IP Right Grant
- 2001-03-30 BR BR0101259A patent/BR0101259A/en active Search and Examination
- 2001-04-02 MX MXPA01003415 patent/MXPA01003415A/en active IP Right Grant
Patent Citations (7)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3247783A (en) * | 1964-05-21 | 1966-04-26 | Erie Foundry Company | Hydraulic press |
FR1595056A (en) * | 1968-12-12 | 1970-06-08 | ||
GB1318183A (en) * | 1969-04-25 | 1973-05-23 | Skelcher H G | Presses for cutting or forming metal or other materials |
DE2528153A1 (en) * | 1975-06-24 | 1977-03-31 | Seiji Shiokawa | Single column hydraulic press - has corrective control device to counteract inaccuracies caused by frame flexure |
US5482454A (en) * | 1992-01-31 | 1996-01-09 | Nissei Plastic Industrial Co., Ltd. | C-type frame for die tightening units mounted for an injection molding machine |
EP0686440A1 (en) * | 1994-05-12 | 1995-12-13 | Benteler Industries, Inc. | Hydroforming apparatus |
US6018971A (en) * | 1998-03-06 | 2000-02-01 | Bentler Ag | Apparatus for hydraulically shaping hollow bodies of metal |
Also Published As
Publication number | Publication date |
---|---|
EP1138410A3 (en) | 2002-05-08 |
AR034846A1 (en) | 2004-03-24 |
DE60106999D1 (en) | 2004-12-16 |
EP1138410B1 (en) | 2004-11-10 |
DE60106999T2 (en) | 2005-04-07 |
BR0101259A (en) | 2001-10-30 |
MXPA01003415A (en) | 2010-11-19 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
US6986273B2 (en) | Apparatus and method for opening and closing stacked hydroforming dies | |
EP0867271B1 (en) | Hydraulic press for forming metal plates | |
US6536251B2 (en) | Apparatus for performing hydroforming operation | |
US5927120A (en) | Apparatus for performing a hydroforming operation | |
JP5047053B2 (en) | Equipment for hydroforming metal elements | |
EP1270107B1 (en) | Apparatus for performing a hydroforming operation | |
US7096700B2 (en) | Method for performing a hydroforming operation | |
WO1992016318A1 (en) | System for working on plate material | |
CN106583567A (en) | Anti-deformation machining die | |
US7124618B1 (en) | Clamp assembly for hydroforming die | |
US6018971A (en) | Apparatus for hydraulically shaping hollow bodies of metal | |
JP3295115B2 (en) | Hydro-elastic deep drawing device | |
US6510720B1 (en) | Hydraulic pressure forming using a self aligning and activating die system | |
EP1138410B1 (en) | Apparatus for performing a hydroforming operation | |
US6170309B1 (en) | Apparatus for simultaneously performing multiple hydroforming operations | |
US6298701B1 (en) | Mechanical press structure adapted to perform hydroforming operations | |
JPS6362293B2 (en) | ||
JP2727954B2 (en) | Press equipment | |
JPH05248405A (en) | Pressurizer of working machine | |
CA2331449A1 (en) | Apparatus and method for hydroforming workpieces | |
JP3453408B2 (en) | Press device with clamping means | |
JP3537352B2 (en) | Hydroforming method and apparatus | |
JPS6258807B2 (en) | ||
SU1493377A1 (en) | Device for to press for expanding large rings by rolling | |
JP2934188B2 (en) | Mold |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
PUAI | Public reference made under article 153(3) epc to a published international application that has entered the european phase |
Free format text: ORIGINAL CODE: 0009012 |
|
AK | Designated contracting states |
Kind code of ref document: A2 Designated state(s): AT BE CH CY DE DK ES FI FR GB GR IE IT LI LU MC NL PT SE TR |
|
AX | Request for extension of the european patent |
Free format text: AL;LT;LV;MK;RO;SI |
|
PUAL | Search report despatched |
Free format text: ORIGINAL CODE: 0009013 |
|
AK | Designated contracting states |
Kind code of ref document: A3 Designated state(s): AT BE CH CY DE DK ES FI FR GB GR IE IT LI LU MC NL PT SE TR |
|
AX | Request for extension of the european patent |
Free format text: AL;LT;LV;MK;RO;SI |
|
17P | Request for examination filed |
Effective date: 20021108 |
|
AKX | Designation fees paid |
Designated state(s): DE GB IT |
|
17Q | First examination report despatched |
Effective date: 20030311 |
|
GRAP | Despatch of communication of intention to grant a patent |
Free format text: ORIGINAL CODE: EPIDOSNIGR1 |
|
GRAS | Grant fee paid |
Free format text: ORIGINAL CODE: EPIDOSNIGR3 |
|
GRAA | (expected) grant |
Free format text: ORIGINAL CODE: 0009210 |
|
AK | Designated contracting states |
Kind code of ref document: B1 Designated state(s): DE GB IT |
|
REG | Reference to a national code |
Ref country code: GB Ref legal event code: FG4D |
|
REG | Reference to a national code |
Ref country code: IE Ref legal event code: FG4D |
|
REF | Corresponds to: |
Ref document number: 60106999 Country of ref document: DE Date of ref document: 20041216 Kind code of ref document: P |
|
PLBE | No opposition filed within time limit |
Free format text: ORIGINAL CODE: 0009261 |
|
STAA | Information on the status of an ep patent application or granted ep patent |
Free format text: STATUS: NO OPPOSITION FILED WITHIN TIME LIMIT |
|
26N | No opposition filed |
Effective date: 20050811 |
|
REG | Reference to a national code |
Ref country code: GB Ref legal event code: 732E Free format text: REGISTERED BETWEEN 20090115 AND 20090121 |
|
REG | Reference to a national code |
Ref country code: GB Ref legal event code: 732E Free format text: REGISTERED BETWEEN 20100415 AND 20100421 |
|
REG | Reference to a national code |
Ref country code: DE Ref legal event code: R081 Ref document number: 60106999 Country of ref document: DE Owner name: METALSA S.A. DE C.V., MX Free format text: FORMER OWNER: DANA AUTOMOTIVE SYSTEMS GROUP, LLC, TOLEDO, US Effective date: 20110803 Ref country code: DE Ref legal event code: R082 Ref document number: 60106999 Country of ref document: DE Representative=s name: BERENDT UND KOLLEGEN, DE Effective date: 20110803 Ref country code: DE Ref legal event code: R081 Ref document number: 60106999 Country of ref document: DE Owner name: METALSA S.A. DE C.V., MX Free format text: FORMER OWNER: DANA AUTOMOTIVE SYSTEMS GROUP, LLC, TOLEDO, OHIO, US Effective date: 20110803 |
|
PGFP | Annual fee paid to national office [announced via postgrant information from national office to epo] |
Ref country code: IT Payment date: 20120326 Year of fee payment: 12 |
|
PGFP | Annual fee paid to national office [announced via postgrant information from national office to epo] |
Ref country code: GB Payment date: 20130327 Year of fee payment: 13 |
|
GBPC | Gb: european patent ceased through non-payment of renewal fee |
Effective date: 20140329 |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: GB Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES Effective date: 20140329 |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: IT Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES Effective date: 20140329 |
|
PGFP | Annual fee paid to national office [announced via postgrant information from national office to epo] |
Ref country code: DE Payment date: 20180322 Year of fee payment: 18 |
|
REG | Reference to a national code |
Ref country code: DE Ref legal event code: R119 Ref document number: 60106999 Country of ref document: DE |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: DE Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES Effective date: 20191001 |