Blanking and feeding integrated impact hydraulic forming die and impact hydraulic forming method

Abstract

The application provides a blank holder and material supplement integrated impact hydraulic forming die and impact hydraulic forming method, and belongs to the technical field of metal forming. The impact hydraulic forming die comprises a lower die with a forming die cavity; a blank holder ring which is arranged on a plate during a forming operation of the die to form a pressing hold on the plate; and a working sleeve assembly which is sleeved on the radial outer side of the blank holder ring and is sealingly connected between the first end surface of the lower die, wherein the working sleeve of the working sleeve assembly has a liquid chamber for accommodating liquid medium and a stamping acceleration channel, a throttling flow channel is formed between the end of the working sleeve facing the lower die and the end of the blank holder ring facing the working sleeve, and the liquid medium in the liquid chamber can be in contact with the thickness side of the plate after being throttled and depressurized through the throttling flow channel. The application can allow the edge of the plate held by the blank holder ring to be supplemented during the forming process of the plate edge descending with the central area of the plate being impacted under the action of pressure, and can effectively improve the forming quality of the target component.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of metal forming, and particularly relates to an integrated impact hydraulic forming die for blank holding and material supplementing and an impact hydraulic forming method. BACKGROUND

[0002] In a traditional plate stamping forming process, a multi-pass and multi-process forming method is often used, and for forming of a large deformation feature, multi-pass deep drawing forming needs to be used, in which the problems of transverse material supplementing and blank holding force are involved. At present, in order to realize the processes of material supplementing, blank holding and forming, a special die needs to be used for multi-pass forming. This manufacturing method not only has high cost and low forming efficiency, but also causes low dimensional accuracy and poor reliability of the final part due to cumulative errors between each pass and each process.

[0003] The impact hydraulic forming technology can form a plate as a whole by only one set of die, through the application of impact energy, the constraint of the die and the matching speed of the rigid impact body to complete the forming of the plate part, but the existing impact hydraulic forming die lacks the related structure design of the integrated blank holding and material supplementing of the plate edge, which leads to high manufacturing cost, low efficiency, poor quality of the target component, and the phenomenon of wrinkling of the plate in the forming process. SUMMARY

[0004] Therefore, the present application provides an integrated impact hydraulic forming die for blank holding and material supplementing and an impact hydraulic forming method, which can solve the technical problems that the existing impact hydraulic forming die lacks the related structure design of the integrated blank holding and material supplementing of the plate edge, which leads to high manufacturing cost, low efficiency, poor quality of the target component, and the phenomenon of wrinkling of the plate in the forming process.

[0005] In order to solve the above problems, the present application provides an integrated impact hydraulic forming die for blank holding and material supplementing, comprising:

[0006] a lower die having a forming die cavity, the shape of the forming die cavity being matched with the shape of a target component;

[0007] a blank holder ring placed on the plate to form blank holding during the forming operation of the die, the blank holder ring having a central through hole corresponding to the position of the cavity opening of the forming die cavity;

[0008] A working sleeve assembly is sealingly connected between the radial outer side of the blank holder and the first end surface of the lower die, and includes a working sleeve having a liquid chamber for containing a liquid medium and a punch acceleration channel for guiding a linear motion of a rigid impact body, and a throttling flow passage is formed between an end of the working sleeve facing the lower die and an end of the blank holder facing the working sleeve, and the liquid medium in the liquid chamber can be in contact with the thickness side of the sheet metal after being throttled and depressurized via the throttling flow passage.

[0009] In some embodiments, the end of the working sleeve facing the lower die is a first conical surface, and the end of the blank holder facing the working sleeve is a second conical surface, and the taper of the first conical surface is equal to that of the second conical surface.

[0010] In some embodiments, the first conical surface has a first flow control structure extending along the circumference thereof, and the second conical surface has a second flow control structure extending along the circumference thereof, and the first flow control structure and the second flow control structure are oppositely spaced to form a throttling annular gap for the liquid medium.

[0011] In some embodiments, in the axial cross section of the working sleeve, the cross-sectional shape of the first flow control structure and the second flow control structure is semicircular.

[0012] In some embodiments, the working sleeve assembly further includes a fixing sleeve sealingly sleeved on the end of the working sleeve facing the lower die, and the working sleeve assembly is sealingly connected with the lower die via the fixing sleeve.

[0013] In some embodiments, a positioning convex ring protruding towards the side of the working sleeve is formed at the cavity opening of the forming die cavity, a positioning ring is sleeved on the positioning convex ring, an upward floating space is formed between the positioning ring and the first end surface, and the liquid medium in the liquid chamber can enter the upward floating space via the throttling flow passage.

[0014] In some embodiments, the friction coefficient of the blank holder and the positioning ring is μ, the surface area of the thickness side of the sheet metal is S1, the pressure of the liquid medium in the liquid chamber is P0, the pressure of the liquid medium after being throttled via the throttling flow passage is P1, the surface area of the second conical surface in the region close to the liquid chamber side of the second flow control structure is S2, the surface area of the second conical surface in the region away from the liquid chamber side of the second flow control structure is S3, the taper angle of the second conical surface is α, the surface area of the side of the positioning ring facing away from the blank holder is S4, P1·S1-μ((P0·S2+P1·S3)cosα+P1·S4)>0, and P1<P0.

[0015] In some embodiments, the friction coefficient of the blank holder is μ, the surface area of the thickness side of the sheet metal is S1, the pressure of the liquid medium in the liquid chamber is P0, the pressure of the liquid medium throttled through the throttle flow channel is P1, the surface area of the second conical surface on the side of the second flow control structure close to the liquid chamber is S2, the surface area of the second conical surface on the side of the second flow control structure away from the liquid chamber is S3, the taper angle of the second conical surface is α, P1·S1-μ(P0·S2+P1·S3)cosα>0, and P1

[0016] The application also provides a method for impact hydraulic forming of sheet metal, which is performed by using the impact hydraulic forming die with integrated blank holder as described above, and comprises the following steps:

[0017] Fixing the lower die on the base;

[0018] Placing the sheet metal on the lower die and covering the cavity opening of the forming die cavity;

[0019] Placing the blank holder on the side of the sheet metal away from the lower die;

[0020] Assembling the working sleeve assembly on the lower die;

[0021] Filling the liquid medium into the liquid chamber;

[0022] Controlling the downward movement of the rigid impact body to impact the liquid medium at a preset pressure.

[0023] The application also provides a method for impact hydraulic forming of sheet metal, which is performed by using the impact hydraulic forming die as described above, and comprises the following steps:

[0024] Fixing the lower die on the base;

[0025] Assembling the positioning ring on the positioning convex ring;

[0026] Placing the sheet metal on the positioning ring and covering the cavity opening of the forming die cavity;

[0027] Placing the blank holder on the side of the sheet metal away from the lower die;

[0028] Assembling the working sleeve assembly on the lower die;

[0029] Filling the liquid medium into the liquid chamber;

[0030] Controlling the downward movement of the rigid impact body to impact the liquid medium at a preset pressure.

[0031] This invention provides an integrated impact hydraulic forming mold and method for edge pressing and material replenishment. The liquid medium in the liquid chamber is guided into the thickness side of the sheet metal, thereby applying a hydraulic pressure in the radial direction during the impact hydraulic forming process. Simultaneously, the liquid medium in the throttling channel applies a vertical component force towards the sheet metal to the edge pressing ring. Under different liquid medium pressures, the hydraulic pressure and vertical component force can be mutually adapted, allowing the edge of the sheet metal held by the edge pressing ring to replenish material as the central region of the sheet metal is impacted and moves downwards during the forming process. This effectively improves the forming quality of the target component, reduces or even eliminates wrinkling during the forming process, and eliminates the need for multiple passes and processes as in traditional forming processes, thus reducing the manufacturing cost of the target component and improving forming efficiency. Attached Figure Description

[0032] Figure 1 This is a schematic diagram (axial section) of an impact hydraulic forming die integrating edge pressing and material replenishment according to an embodiment of the present invention;

[0033] Figure 2 for Figure 1 A schematic diagram of the stress state of relevant components of the mold during the sheet metal forming process;

[0034] Figure 3 This is a schematic diagram (axial section) of an impact hydraulic forming die integrating edge pressing and material replenishment according to another embodiment of the present invention;

[0035] Figure 4 for Figure 2 The diagram illustrates the stress state of relevant components of the mold during the sheet metal forming process.

[0036] The reference numerals in the attached figures are as follows:

[0037] 1. Lower die; 11. Forming cavity; 12. Positioning ring; 2. Pressure ring; 21. Central through hole; 22. Second flow control structure; 3. Working sleeve; 31. Liquid chamber; 32. Stamping acceleration channel; 33. First flow control structure; 34. Vent hole; 4. Throttling channel; 5. Fixing sleeve; 6. Positioning ring; 7. Base; 8. Rigid impact body; 100. Sheet metal. Detailed Implementation

[0038] See also Figures 1 to 4 As shown, according to an embodiment of the present invention, an impact hydraulic forming die integrating edge pressing and material replenishment is provided, see details below. Figure 1 As shown, the impact hydroforming die with integrated edge clamping and material replenishment includes:

[0039] The lower die 1 has a forming cavity 11, the shape of which matches the shape of the target component, which is the shape of the plate 100 to be finally processed.

[0040] The pressure ring 2 is placed on the sheet 100 during the forming process of the mold to press the sheet 100. The pressure ring 2 has a central through hole 21, which corresponds to the position of the cavity opening of the forming mold cavity 11. The central through hole 21 allows the impact to be applied to the sheet 100, thereby achieving the purpose of forming the sheet 100.

[0041] The working sleeve assembly (not labeled in the figure) is fitted radially outward of the pressure ring 2 and is flush with the first end face of the lower die 1. Figure 1 The sealing connection between the first end face (which is the top face of the lower die 1) and the shown range can be achieved, for example, by setting a sealing ring or other structure at the mating position of the two. The working sleeve assembly includes a working sleeve 3, which has a liquid chamber 31 for containing liquid medium and a stamping acceleration channel 32 for guiding the linear motion of the rigid impact body 8 (driven by a stamping device, not shown in the figure). See [reference] Figure 1 or Figure 3 As shown, the stamping acceleration channel 32 and the liquid chamber 31 are arranged sequentially along the downward punching direction of the rigid impact body 8. At the junction of the two, the working sleeve 3 is constructed with a corresponding vent hole 34 to prevent the impact of the rigid impact body 8 from directly contacting the liquid surface and to ensure efficient force transmission. A throttling channel 4 is formed between the end of the working sleeve 3 facing the lower die 1 (which can be understood as the bottom end) and the end of the pressure ring 2 facing the working sleeve 3 (which can be understood as the top end). This channel can throttle and reduce the pressure of the liquid medium flowing through it. In this way, the liquid medium in the liquid chamber 31 can contact the thickness side of the plate 100 after being throttled and reduced in pressure through the throttling channel 4. This allows the reduced pressure liquid medium to exert a thrust on the plate 100 from the edge to the middle, which is beneficial for the replenishment of the plate 100. The aforementioned thickness side is the side surface where the thickness of the plate 100 is located, which can also be understood as the outer peripheral wall surface of the plate 100 (excluding the top and bottom surfaces).

[0042] In this technical solution, unlike the impact hydraulic forming molds in the prior art, the liquid medium in the liquid chamber 31 is guided into the thickness side position of the sheet 100, thereby enabling the application of a hydraulic pressure (such as...) to the sheet 100 in the radial direction during the impact hydraulic forming process. Figure 2 and Figure 4 (F3 in the middle), at the same time, the liquid medium in the throttling channel 4 applies a vertical component force (e.g., F3) towards the pressure ring 2 towards the plate 100. Figure 2 and Figure 4The hydraulic force and the vertical component force can be matched to allow the edge of the plate 100 held by the pressure ring 2 to be replenished during the forming process of the middle area of the plate 100 under the impact of the vertical component force under the pressure of the different liquid media, so as to effectively improve the forming quality of the target component. Since the plate can be replenished from the holding edge to the deformation area during the plate forming process, the wrinkling phenomenon of the plate during the forming process can be reduced or even eliminated, the operation of multiple passes and multiple processes in the traditional forming process is not needed, the manufacturing cost of the target component is reduced, and the forming efficiency is improved.

[0043] In some embodiments, one end of the working sleeve 3 towards the lower die 1 is a first conical surface, one end of the pressure ring 2 towards the working sleeve 3 is a second conical surface, the taper of the first conical surface is equal to the taper of the second conical surface, specifically, the bottom surface of the first conical surface and the second conical surface is towards the side where the lower die 1 is located, and the flow channel formed between the two conical surfaces is the throttling flow channel mentioned above, that is, the working sleeve 3 and the pressure ring 2 are not physically connected, and the two are independent of each other. The matching position of the two forms an annular gap, which is the throttling flow channel mentioned above. In this way, the holding force of the pressure ring 2 on the plate 100 can be controlled and adjusted according to the pressure of the liquid medium in the liquid chamber 31, and then the control of the replenishment amount and speed of the plate 100 can be realized.

[0044] In a preferred embodiment, the first conical surface has a first flow control structure 33 extending along the circumference thereof, and the second conical surface has a second flow control structure 22 extending along the circumference thereof, the first flow control structure 33 and the second flow control structure 22 are oppositely spaced to form a throttling annular gap (annular gap) for the liquid medium, that is, the throttling flow channel 4 is provided with the first flow control structure 33 and the second flow control structure 22, and the size of the first flow control structure 33 and the second flow control structure 22 adjusts the flow area of the throttling annular gap, so as to adjust the pressure of the liquid medium in the area where the liquid chamber 31 enters the thickness side of the plate 100, which is beneficial to adjust the feeding amount and speed control of the plate 100. The first flow control structure 33 and the second flow control structure 22 can be integrally formed with the working sleeve 3 and the pressure ring 2 respectively, at this time, when the pressure reduction needs to be adjusted, the corresponding parts with different sizes of flow control structures can be replaced; and as a more preferred implementation, the first flow control structure 33 and the second flow control structure 22 are respectively detachably connected to the corresponding conical surface, at this time, when the throttling pressure reduction effect needs to be adjusted, only the flow control structure with different sizes needs to be replaced, and the mold manufacturing cost can be effectively reduced. In a specific embodiment, in the axial section of the working sleeve 3, the cross-sectional shape of the first flow control structure 33 and the second flow control structure 22 is semicircular, at this time, the radius of the flow control structure can be changed to achieve different pressure reduction effects, and the design and manufacturing difficulty of the flow control structure is simplified. It should be particularly pointed out that the throttling flow channel 4 in the present application is downwardly inclined from the liquid chamber 31, which can ensure smooth flow of the liquid medium.

[0045] The working sleeve assembly further comprises a fixing sleeve 5, which is sealingly sleeved on one end of the working sleeve 3 facing the lower die 1, and can reliably support the working sleeve 3. The working sleeve assembly is sealingly connected to the lower die 1 through the fixing sleeve 5, and the lower die 1 is fixedly connected to the base 7. In this way, the fixing sleeve 5, the working sleeve 3 and the lower die 1 form a stable whole during the forming process of the plate, the fixing sleeve 5 and the working sleeve 3 can be detachably connected in a threaded connection manner, and the fixing sleeve 5 and the lower die 1 can be connected in a plug-in die connection manner, and a corresponding sealing ring can be further added to achieve sealing and prevent the liquid medium from leaking out of the fitting gap.

[0046] In another specific embodiment, referring to Figure 3 and Figure 4As shown, the cavity mouth of the forming cavity 11 is formed with a positioning convex ring 12 protruding towards the side of the working sleeve 3, the positioning convex ring 12 is sleeved with the positioning ring 6, and the positioning ring 6 and the first end face form a floating space, the liquid medium in the liquid chamber 31 can enter the floating space through the throttling flow channel 4, and it can be understood that the sleeving cooperation between the positioning convex ring 12 and the positioning ring 6 should be in a sealed state under the premise that the positioning ring 6 can float up and down within a certain range, so as to prevent the liquid medium from flowing through the gap between the two. The specific sealing connection between the two can be achieved by sealing methods such as grease. Figure 1 Unlike the embodiments shown, the depressurized liquid medium in this technical solution can not only exert a pushing force on the thickness side of the plate 100 to achieve the purpose of replenishment, but also enter the aforementioned floating space to exert a vertical upward supporting force on the plate 100 during the forming process, and the supporting force can be adjusted in size. Thus, the forming quality of the target component can be further improved. For details, see Figure 4 As shown, F2 vertically upwardly objectively plays a role in floating the positioning ring 6, when F2 is large, the upward force lifts the plate 100 and the positioning ring 6 upward, then the forming time of the plate 100 during the forming process becomes longer, at the same time, the contact range of the plate 100 with the round chamfer of the die (i.e. the inner hole top hole mouth edge position of the positioning convex ring 12) becomes larger, so the replenishment time will also be correspondingly longer, which can improve the forming quality of the plate 100.

[0047] The specific manufacturing materials of the blank holder ring 2, the positioning ring 6 and the lower die plate 1 are generally the same, of course, in some cases, different materials can also be selected, in order to facilitate the control of replenishment, the preferred solution is that the manufacturing materials of the blank holder ring 2, the positioning ring 6 and the lower die plate 1 are the same, at this time they have the same friction coefficient, which is set as μ.

[0048] See Figure 4As shown, during the forming operation of the mold, the surface area of the thickness side of the plate 100 is S1, the pressure of the liquid medium in the liquid chamber 31 is P0, the pressure of the liquid medium throttled through the throttling flow channel 4 is P1, the surface area of the second conical surface in the region close to the liquid chamber 31 of the second flow control structure 22 is S2, the surface area of the second conical surface in the region away from the liquid chamber 31 of the second flow control structure 22 is S3, the taper angle of the second conical surface is a, the surface area of the side of the positioning ring 6 away from the blank holder 2 is S4, P1·S1-μ((P0·S2+P1·S3)cos a+P1·S4)>0, P1

[0049] Referring to Figure 2 As shown, during the forming operation of the mold, the surface area of the thickness side of the plate 100 is S1, the pressure of the liquid medium in the liquid chamber 31 is P0, the pressure of the liquid medium throttled through the throttling flow channel 4 is P1, the surface area of the second conical surface in the region close to the liquid chamber 31 of the second flow control structure 22 is S2, the surface area of the second conical surface in the region away from the liquid chamber 31 of the second flow control structure 22 is S3, the taper angle of the second conical surface is a, P1·S1-μ((P0·S2+P1·S3)cos a+P1·S4)>0, P1

[0050] According to the embodiment of the present application, an impact hydraulic forming method of a plate is also provided, which is performed by using the impact hydraulic forming mold with blank holding and feeding integration in Figure 1 , and includes the following steps:

[0051] Fixing the lower die 1 on the base 7;

[0052] Placing the plate 100 on the lower die 1 and covering the cavity opening of the forming cavity 11;

[0053] Placing the blank holder 2 on the side of the plate 100 away from the lower die 1;

[0054] Assembling the work sleeve assembly on the lower die 1;

[0055] Filling the liquid medium into the liquid chamber 31;

[0056] The rigid impactor 8 is controlled to move downward to impact the liquid medium with a preset pressure. The impact of the rigid impactor 8 on the liquid medium forms a pressure wave that is transmitted downward within the liquid medium and further applied to the middle position of the plate 100 (the part of the plate 100 located at the cavity opening of the forming mold cavity 11). Under the action of this impact force, the plate 100 undergoes plastic deformation towards the forming mold cavity 11 and finally forms the target component by adhering to the mold. During this process, the edge of the plate 100 is subjected to a vertical holding force of (P0·S2+P1·S3)cosα by the edge pressure ring 2, while the thick sidewall is subjected to the force of P1·S1 to achieve material replenishment.

[0057] Specifically, see [link / reference] Figure 1 and Figure 2 In this embodiment, according to the command of the power system, the rapidly flying rigid impactor 8 impacts the liquid medium, generating pulsed high pressure therein, and then pulsed high pressure forming is performed on the sheet 100, wherein the forming process can be subdivided into the following three parts:

[0058] (1) The first part is the high pressure load action. The process is as follows: the working sleeve assembly and the lower die 1 remain stationary after the mold is closed. Then the power system (stamping device) of the liquid-filled impact hydraulic forming equipment starts to charge energy. After reaching the set value, it is released and the energy is applied to the rigid impact body 8. The rigid impact body 8 obtains a very high speed under the action of the released energy and quickly strikes the surface of the liquid medium to generate pulse high pressure. The pulse high pressure propagates along the liquid medium to the plate 100 and causes the plate 100 to undergo plastic deformation.

[0059] (2) The second part is the hydraulic pressing action, the process is as follows: due to the regulation of the flow control device (i.e. the aforementioned first flow control structure 33 and second flow control structure 22, the same below) and the flow distribution device (i.e. the aforementioned throttling channel 4), the liquid medium fills the plate 100 and the inner cavity of the die cavity (i.e. the aforementioned forming die cavity 11), and the liquid generates normal hydraulic pressure on the inclined surface ( Figure 4 In the equation F1), the vertically downward hydraulic pressure is F1cosα. Plate 100 is subjected to the vertical components of the thickness-feeding pressure and the normal pressure from the inclined plane of the diversion device, but not the upward liquid pressure from the bottom. Therefore, according to the force analysis, plate 100 experiences a resultant force of F1 in the vertical direction, which is downward. At this point, liquid-solid-solid load transfer can be achieved to complete the edge pressing, as shown below. Figure 2 As shown.

[0060] (3) The third part is the feeding and replenishing process: Due to the continuous action of the liquid medium, the plate 100 continues to deform under the action of pulsed high pressure and gradually fills the concave mold cavity. The liquid high pressure load generates a feeding pressure of F3=P*S3-μF1cosα on the outer edge wall of the plate 100, which in turn pushes the edge of the plate 100 towards the center to complete the feeding.

[0061] Thus, the forming is completed, the mold is opened, and the target member is removed.

[0062] According to the embodiment of the present application, a plate impact hydraulic forming method is also provided, which is performed by using the impact hydraulic forming die in Figure 3 , and includes the following steps:

[0063] Fix the lower die 1 on the base 7;

[0064] Fit the positioning ring 6 on the positioning convex ring 12;

[0065] Place the plate 100 on the positioning ring 6 and cover the cavity opening of the forming die cavity 11;

[0066] Place the blank holder 2 on the side of the plate 100 away from the lower die 1;

[0067] Assemble the working sleeve assembly on the lower die 1;

[0068] Fill the liquid medium into the liquid chamber 31;

[0069] Control the downward movement of the rigid impact body 8 to impact the liquid medium at a preset pressure.

[0070] Specifically, in combination with Figure 3 and Figure 4 , in this embodiment, according to the instruction of the power system, the fast-flying rigid impact body 8 impacts the liquid medium to generate a pulse high pressure therein, and then performs pulse high pressure forming on the plate 100, wherein the forming process can be divided into the following three parts:

[0071] (1) The first part is high pressure load action, the process is as follows: after the working sleeve assembly and the lower die 1 are kept stationary after the mold is closed, the power system of the liquid filling and impact hydraulic forming equipment is started to charge, and after reaching the set value, it is released to enable the energy to act on the rigid impact body 8, which obtains a very high speed under the action of the released energy and quickly strikes the surface of the liquid medium to generate a pulse high pressure, the set hydraulic pressure is F1, and the pulse high pressure propagates along the liquid medium to the plate 100 and makes the plate 100 plastically deform.

[0072] (2) The second part is hydraulic blank holding action, the process is as follows: due to the regulation of the flow control device and the flow distribution device, the liquid medium fills the plate and the inner cavity of the die, the liquid generates a normal hydraulic pressure F1 on the inclined surface, the vertically downward hydraulic pressure is F1cosα, and the liquid 7 generates an upward hydraulic pressure F2 on the positioning ring 9, when F1cosα<F2, according to the force analysis, the plate receives a vertical resultant force upward, and the transition fillet of the lower die 1 is used. At this time, liquid-solid-solid load transfer can be achieved to complete blank holding, which is more conducive to the forming of the plate, as shown in Figure 4 .

[0073] (3) The third part is to supply the role of feeding, the process is: due to the continuous effect of the liquid medium, the plate 100 is continuously deformed under the action of pulse high pressure, and gradually fills the concave model cavity. The liquid high pressure load generates a feeding pressure F3=P*S3-μ(F1cosα+F2) on the outer edge vertical wall of the plate 100, thereby pushing the edge of the plate 100 to the middle to complete the feeding.

[0074] In this way, the forming is completed, the mold is opened, and the target member can be taken out.

[0075] Those skilled in the art can easily understand that the advantageous technical features of the above-mentioned various modes can be freely combined and superimposed without conflict.

[0076] The above is only a preferred embodiment of the present application, and is not intended to limit the present application. Any modifications, equivalent replacements and improvements made within the spirit and principles of the present application shall be included in the protection scope of the present application. The above is only a preferred embodiment of the present application, and it should be pointed out that, for ordinary skilled in the art, without departing from the technical principles of the present application, a number of improvements and modifications can be made, and these improvements and modifications shall be regarded as the protection scope of the present application.

Claims

1. A pressurized edge material integrated impact hydraulic forming die, characterized by, The utility model relates to a kind of stamping die, including: Lower die (1) with forming cavity (11), the shape of the forming cavity (11) is matched with target component shape; Blank holder (2) is placed on sheet (100) to form hold to the sheet (100) during the forming operation of die, the blank holder (2) has center through hole (21), and the cavity opening position of the forming cavity (11) is corresponded; Working sleeve assembly is sealedly connected between the radial outside of the blank holder (2) and the first end surface of the lower die (1), and the working sleeve assembly includes working sleeve (3), the working sleeve (3) has liquid chamber (31) for containing liquid medium and punch acceleration channel (32) for guiding the linear motion of rigid impact body (8), the rigid impact body (8) can be controlled to descend and impact liquid medium in the liquid chamber (31) with preset pressure, and the end of the working sleeve (3) towards the lower die (1) and the end of the blank holder (2) towards the working sleeve (3) form throttling flow channel (4), and liquid medium in the liquid chamber (31) can be contacted with the thickness side of sheet (100) after throttling and pressure reduction via the throttling flow channel (4).

2. The impact hydroforming die according to claim 1, wherein The end of the working sleeve (3) towards the lower die (1) is first conical surface, and the end of the blank holder (2) towards the working sleeve (3) is second conical surface, and the tapers of the first conical surface and the second conical surface are equal.

3. The impact hydroforming die of claim 2, wherein, The first conical surface has first flow control structure (33) extending along its circumference, and the second conical surface has second flow control structure (22) extending along its circumference, and the first flow control structure (33) and the second flow control structure (22) are oppositely spaced to form throttling annular gap to the liquid medium.

4. The impact hydroforming die of claim 3, wherein In the axial section of the working sleeve (3), the cross-sectional shape of the first flow control structure (33) and the second flow control structure (22) is semicircular.

5. The impact hydroforming die of claim 1 wherein, The working sleeve assembly further includes fixed sleeve (5), and the fixed sleeve (5) is sealedly sleeved on the end of the working sleeve (3) towards the lower die (1), and the working sleeve assembly is sealedly connected with the lower die (1) through the fixed sleeve (5).

6. The impact hydroforming die of claim 3 wherein, The cavity opening of the forming cavity (11) is formed with positioning convex ring (12) protruding towards the side of the working sleeve (3), the positioning ring (6) is sleeved on the positioning convex ring (12), the positioning ring (6) forms floating space between the first end surface, and liquid medium in the liquid chamber (31) can enter the floating space via the throttling flow channel (4).

7. The impact hydroforming die of claim 6 wherein, The friction coefficient of the blank holder (2) is μ, the surface area of the thickness side of the plate (100) is S1, the pressure of the liquid medium in the liquid chamber (31) is P0, the pressure of the liquid medium throttled through the throttle flow channel (4) is P1, the surface area of the second conical surface in the region close to the liquid chamber (31) of the second flow control structure (22) is S2, the surface area of the second conical surface in the region away from the liquid chamber (31) of the second flow control structure (22) is S3, the cone angle of the second conical surface is α, and P1·S1-μ((P0·S2+P1·S3)cosα+P1·S4)>0, P1 8. The impact hydroforming die of claim 3 wherein, The friction coefficient of the blank holder (2) is μ, the surface area of the thickness side of the plate (100) is S1, the pressure of the liquid medium in the liquid chamber (31) is P0, the pressure of the liquid medium throttled through the throttle flow channel (4) is P1, the surface area of the second conical surface in the region close to the liquid chamber (31) of the second flow control structure (22) is S2, the surface area of the second conical surface in the region away from the liquid chamber (31) of the second flow control structure (22) is S3, the cone angle of the second conical surface is α, and P1·S1-μ((P0·S2+P1·S3)cosα+P1·S4)>0, P1 9. A method of impact hydroforming of a sheet material, characterized by, The impact hydraulic forming die with integrated blank holder and material feeding according to any one of claims 1 to 5 and 8 is used to perform the following steps: Fix the lower die (1) on the base (7); Place the plate (100) on the lower die (1) and cover the cavity opening of the forming die cavity (11); Place the blank holder (2) on the side of the plate (100) away from the lower die (1); Assemble the working sleeve assembly on the lower die (1); Fill the liquid medium into the liquid chamber (31); Control the downward movement of the rigid impact body (8) to impact the liquid medium at a preset pressure.

10. A method of impact hydroforming of a sheet material, characterized by, The impact hydraulic forming die according to claim 6 or 7 is used to perform the following steps: Fix the lower die (1) on the base (7); Place the plate (100) on the lower die (1) and cover the cavity opening of the forming die cavity (11); Place the blank holder (2) on the side of the plate (100) away from the lower die (1); Assemble the working sleeve assembly on the lower die (1); Fill the liquid medium into the liquid chamber (31); Control the downward movement of the rigid impact body (8) to impact the liquid medium at a preset pressure. ​

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