Molding tools and methods for helicopter tail rotor blade balance bearings

Abstract

The application discloses a forming tool for a helicopter tail rotor blade balance support and relates to the technical field of aircraft forming. A limiting recess is formed in the top surface of the lower die, the bottom surface of the limiting recess is provided with a lower forming male die, a plurality of lower ejection holes are formed in the bottom surface of the limiting recess, the middle die can be arranged in the limiting recess, the middle die is provided with a forming hole, the bottom surface of the upper die is provided with an upper forming male die, and the bottom surface of the upper die is provided with a plurality of upper ejection holes; the top surface of the lower forming male die, the bottom surface of the upper forming male die and the inner side wall of the forming hole surround a forming chamber of the balance support; the top end of the lower ejection pin can pass through the lower ejection hole and can be in contact with the bottom surface of the middle die; the bottom end of the upper ejection pin can pass through the upper ejection hole and the top end of the upper ejection pin can be in contact with the top surface of the lower die; and the application can effectively improve the manufacturing efficiency of the balance support.

Description

Technical Field

[0001] This invention relates to the field of aerospace product molding technology, and in particular to a molding tool and method for a helicopter tail rotor blade balance support. Background Technology

[0002] The tail rotor blades are mounted at the tail of the helicopter. By changing the thrust of the tail rotor, the helicopter's heading can be controlled, making the helicopter more stable and maneuverable in flight. The balance support, located in the middle and rear part of the tail rotor blades, is used for the overall balance and counterweight of the tail rotor blades and is an important component of the tail rotor blades. A balance support with a square outer contour and irregularly shaped top and bottom surfaces, made of chopped fiber, needs to be manufactured. How to quickly and efficiently produce this balance support has become an urgent problem to be solved. Summary of the Invention

[0003] The purpose of this invention is to provide a forming tool and method for a helicopter tail rotor blade balance support, so as to solve the problems existing in the prior art and effectively improve the manufacturing efficiency of the balance support.

[0004] To achieve the above objectives, the present invention provides the following solution:

[0005] This invention provides a forming tool for a helicopter tail rotor blade balance support, including an upper mold, a middle mold, a lower mold, an upper unloading template, and a lower unloading template. The lower mold has a limiting groove on its top surface, and a lower forming punch on the bottom surface of the limiting groove. Several lower ejector holes are formed on the bottom surface of the limiting groove, each ejector hole surrounding the lower forming punch. The middle mold can be placed within the limiting groove and has forming holes. The upper mold is positioned above the lower mold and the middle mold. The upper mold has an upper forming punch on its bottom surface, and several upper ejector holes are formed on its bottom surface, each ejector hole surrounding the upper forming punch. The lower forming punch can extend into the forming hole from below, and the upper forming punch can extend into the forming hole from above. The top surface of the lower forming punch, the bottom surface of the upper forming punch, and the inner wall of the forming hole form a forming chamber for a balance support. The lower unloading platen is placed below the lower die, and a number of lower ejector pins are fixedly arranged on the lower unloading platen. The number of lower ejector pins is equal to the number of lower ejector holes. Each lower ejector pin corresponds to a lower ejector hole. The top end of each lower ejector pin can pass through the lower ejector hole and can contact the bottom surface of the middle die. The upper unloading platen is placed above the upper die, and a number of upper ejector pins are fixedly arranged on the upper unloading platen. The number of upper ejector pins is equal to the number of upper ejector holes. Each upper ejector pin corresponds to an upper ejector hole. The bottom end of each upper ejector pin can pass through the upper ejector hole and the top end of each upper ejector pin can contact the top surface of the lower die.

[0006] Preferably, a first demolding gap is left between the outer wall of the middle mold and the inner wall of the limiting groove.

[0007] Preferably, a second demolding gap is provided between the outer wall of the lower forming punch and the inner wall of the forming hole, and a third demolding gap is provided between the outer wall of the upper forming punch and the inner wall of the forming hole.

[0008] Preferably, the bottom surface of the intermediate mold has a first rounded corner at the connection between it and the inner wall of the forming hole, and the top surface of the intermediate mold has a second rounded corner at the connection between it and the inner wall of the forming hole.

[0009] Preferably, the middle mold includes a middle left mold and a middle right mold. A left forming groove is provided on the right side of the middle left mold, and a right forming groove is provided on the left side of the middle right mold. The middle left mold and the middle right mold can be assembled to form the middle mold, and the left forming groove and the right forming groove form the forming hole.

[0010] Preferably, a pry opening is provided at the joint between the middle left mold and the middle right mold.

[0011] Preferably, the lower unloading template is threadedly connected to the lower ejector pin.

[0012] Preferably, the upper unloading template is threadedly connected to the upper ejector pin.

[0013] Preferably, there are two lower forming punches, two forming holes on the middle die, and two upper forming punches, with each of the lower forming punch, forming hole, and upper forming punch corresponding to the other.

[0014] The present invention also provides a method for forming a helicopter tail rotor blade balance support, which uses the forming tool for the helicopter tail rotor blade balance support described above to manufacture the helicopter tail rotor blade balance support, including the following steps:

[0015] Step 1: Preheat the upper mold, middle mold, and lower mold;

[0016] Step 2: Place the middle mold in the limiting groove on the lower mold, and make the lower forming punch extend into the forming hole from below;

[0017] Step 3: Add the chopped fibers into the forming holes on the die;

[0018] Step 4: Place the upper mold above the lower mold and the middle mold, and extend the upper forming punch into the forming hole from above;

[0019] Step 5: Place the closed assembly of the upper mold, middle mold and lower mold obtained in Step 4 onto a hot press, pressurize and heat it, then maintain the pressure and cool it.

[0020] Step 6: Place the lower unloading template on the press, place the upper mold, middle mold and lower mold assembly closed body above the lower unloading template, and make the top of the lower ejector pin pass through the lower ejector hole and contact the bottom surface of the middle mold. Place the upper unloading template above the upper mold, middle mold and lower mold assembly closed body, and make the bottom of the upper ejector pin pass through the upper ejector hole and contact the top surface of the lower mold.

[0021] Step 7: Start the press, separate the upper mold, middle mold and lower mold, and remove the balance support in the forming hole.

[0022] The present invention achieves the following technical effects compared to the prior art:

[0023] The present invention provides a molding tool and method for a helicopter tail rotor balance bearing. The intermediate mold is placed in a limiting groove on the lower mold, effectively limiting the intermediate mold. This allows the lower forming punch to extend into the forming hole from below, and the upper forming punch to extend into the forming hole from above, forming the molding chamber of the balance bearing. In use, before extending the upper forming punch into the forming hole from above, short-cut fibers are added to the forming hole on the intermediate mold. Then, the upper forming punch extends into the forming hole from above. Finally, the combined closed assembly of the upper mold, intermediate mold, and lower mold is placed on a hot press to shape the balance bearing. The short fibers in the molding chamber are hot-pressed and cured. After holding the pressure and cooling, the top end of the lower ejector pin passes through the lower ejector hole and contacts the bottom surface of the middle mold, and the bottom end of the upper ejector pin passes through the upper ejector hole and contacts the top surface of the lower mold. The press pressure is used to move the lower ejector pin and the upper ejector pin towards each other, thereby separating the upper mold, middle mold and lower mold. Then the balance support in the molding hole can be taken out. The molding tool for the helicopter tail rotor balance support provided in this embodiment has a simple structure, which is convenient for hot pressing of the balance support and easy to demold, thereby effectively improving the manufacturing efficiency of the balance support. Attached Figure Description

[0024] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0025] Figure 1 A schematic diagram of the forming tool for the helicopter tail rotor blade balance support provided by the present invention;

[0026] In the diagram: 1-lower unloading template, 2-lower ejector pin, 3-lower mold, 4-middle right mold, 5-middle left mold, 6-balance support, 7-upper mold, 8-upper ejector pin, 9-upper unloading template. Detailed Implementation

[0027] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0028] The purpose of this invention is to provide a forming tool and method for a helicopter tail rotor blade balance support, so as to solve the problems existing in the prior art and effectively improve the manufacturing efficiency of the balance support.

[0029] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0030] Example 1

[0031] like Figure 1 As shown, this embodiment provides a forming tool for a helicopter tail rotor balance support, including an upper mold 7, a middle mold, a lower mold 3, an upper ejector plate 9, and a lower ejector plate 1. A limiting groove is formed on the top surface of the lower mold 3, and a lower forming punch is formed on the bottom surface of the limiting groove. Several lower ejector holes are formed on the bottom surface of the limiting groove, and each lower ejector hole surrounds the lower forming punch. The middle mold can be placed inside the limiting groove and has forming holes. The upper mold 7 is placed above the lower mold 3 and the middle mold. An upper forming punch is formed on the bottom surface of the upper mold 7, and several upper ejector holes are formed on the bottom surface of the upper mold 7, and each upper ejector hole surrounds the upper forming punch. The lower forming punch can extend into the forming hole from below, and the upper forming punch can extend into the forming hole from above. The top surface of the lower forming punch, the bottom surface of the upper forming punch, and the inner wall of the forming hole form a forming chamber of a balance support. The lower ejector plate 1 is placed below the lower mold 3. Several lower ejector pins 2 are fixedly arranged on the lower ejector plate 1. The number of lower ejector pins 2 is equal to the number of lower ejector holes. The lower ejector pins 2 correspond one-to-one with the lower ejector holes. The top of the lower ejector pin 2 can pass through the lower ejector hole and the top of the lower ejector pin 2 can contact the bottom surface of the middle mold. The upper ejector plate 9 is placed above the upper mold 7. Several upper ejector pins 8 are fixedly arranged on the upper ejector plate 9. The number of upper ejector pins 8 is equal to the number of upper ejector holes. The upper ejector pins 8 correspond one-to-one with the upper ejector holes. The bottom of the upper ejector pin 8 can pass through the upper ejector hole and the top of the upper ejector pin 8 can contact the top surface of the lower mold 3.

[0032] The forming tool for the helicopter tail rotor balance bearing provided in this embodiment places the middle mold in the limiting groove on the lower mold 3, which can effectively limit the middle mold, allowing the lower forming punch to extend into the forming hole from below, and the upper forming punch to extend into the forming hole from above, thus forming the forming cavity of the balance bearing. In use, before extending the upper forming punch into the forming hole from above, short-cut fibers are added to the forming hole on the middle mold, and then the upper forming punch is extended into the forming hole from above. Finally, the combined closed body of the upper mold 7, middle mold, and lower mold 3 is placed on a hot press to form the forming cavity of the balance bearing. The short-cut fibers can be hot-pressed and cured indoors. After holding pressure and cooling, the top end of the lower ejector pin 2 is made to pass through the lower ejector hole and contact the bottom surface of the middle mold, and the bottom end of the upper ejector pin 8 is made to pass through the upper ejector hole and contact the top surface of the lower mold 3. The press pressure is used to move the lower ejector pin 2 and the upper ejector pin 8 towards each other, thereby separating the upper mold 7, the middle mold and the lower mold 3. Then the balance support 6 in the forming hole can be taken out. The forming tool of the helicopter tail rotor balance support provided in this embodiment has a simple structure, which is convenient for hot pressing the balance support 6 and easy to demold, thereby effectively improving the production efficiency of the balance support 6.

[0033] As a preferred embodiment of this invention, a first demolding gap is left between the outer wall of the middle mold and the inner wall of the limiting groove, which facilitates assembly and demolding and improves the manufacturing efficiency of the balance support 6.

[0034] As a preferred embodiment of this invention, a second demolding gap is provided between the outer wall of the lower forming punch and the inner wall of the forming hole, and a third demolding gap is provided between the outer wall of the upper forming punch and the inner wall of the forming hole, which facilitates assembly and demolding and improves the manufacturing efficiency of the balance support 6.

[0035] As a preferred embodiment of this invention, the bottom surface of the middle mold has a first rounded corner at the connection with the inner wall of the forming hole, and the top surface of the middle mold has a second rounded corner at the connection with the inner wall of the forming hole. This can serve as a guide to prevent the upper forming punch and the lower forming punch from being bumped and damaged.

[0036] As a preferred embodiment of this invention, the middle mold includes a left middle mold 5 and a right middle mold 4. A left forming groove is formed on the right side of the left middle mold 5, and a right forming groove is formed on the left side of the right middle mold 4. The left middle mold 5 and the right middle mold 4 can be assembled to form the middle mold, and the left forming groove and the right forming groove form a forming hole. The structure is simple, easy to assemble and demold, and improves the manufacturing efficiency of the balance support 6. It should be understood that the terms "left" and "right" are based on the orientation or positional relationship shown in the drawings and are only for the convenience of describing the present invention, and should not be construed as limiting the present invention.

[0037] As a preferred embodiment of this invention, a pry hole is provided at the joint of the left middle mold 5 and the right middle mold 4 to facilitate demolding and improve the manufacturing efficiency of the balance support 6.

[0038] As a preferred embodiment of this invention, the lower unloading template 1 and the lower ejector pin 2 are threaded together for easy disassembly and assembly; as an optional embodiment of this invention, the lower unloading template 1 and the lower ejector pin 2 are assembled together by an interference fit, making the connection more stable.

[0039] As a preferred embodiment of this invention, the upper unloading template 9 and the upper ejector pin 8 are threaded together for easy disassembly and assembly; as an optional embodiment of this invention, the upper unloading template 9 and the upper ejector pin 8 are assembled together by an interference fit, making the connection more stable.

[0040] As a preferred embodiment of this invention, there are two lower forming punches, two forming holes on the middle die, and two upper forming punches. The lower forming punches, forming holes, and upper forming punches correspond one-to-one, which can effectively improve the production efficiency of the product.

[0041] Example 2

[0042] This embodiment provides a method for forming a helicopter tail rotor blade balance support. The method utilizes the forming tool for the helicopter tail rotor blade balance support described in Embodiment 1 to fabricate the helicopter tail rotor blade balance support 6, and includes the following steps:

[0043] Step 1: Preheat the upper mold 7, middle mold and lower mold 3;

[0044] Step 2: Place the middle mold in the limiting groove on the lower mold 3, and make the lower forming punch extend into the forming hole from below;

[0045] Step 3: Add the chopped fibers into the forming holes on the die;

[0046] Step 4: Place the upper mold 7 above the lower mold 3 and the middle mold, and extend the upper forming punch into the forming hole from above;

[0047] Step 5: Place the closed assembly of the upper mold 7, middle mold and lower mold 3 obtained in Step 4 onto a hot press and pressurize it, then maintain the pressure and cool it.

[0048] Step 6: Place the lower unloading template 1 on the press, place the upper mold 7, middle mold and lower mold 3 combined closed body above the lower unloading template 1, and make the top end of the lower ejector pin 2 pass through the lower ejector hole and contact the bottom surface of the middle mold. Place the upper unloading template 9 above the upper mold 7, middle mold and lower mold 3 combined closed body, and make the bottom end of the upper ejector pin 8 pass through the upper ejector hole and contact the top surface of the lower mold 3.

[0049] Step 7: Start the press, separate the upper mold 7, middle mold and lower mold 3, and remove the balance support 6 from the forming hole.

[0050] The method for forming a helicopter tail rotor balance support provided in this embodiment involves placing the middle mold in a limiting groove on the lower mold 3, which effectively limits the middle mold. This allows the lower forming punch to extend into the forming hole from below, and the upper forming punch to extend into the forming hole from above, thus forming the forming cavity of the balance support. In use, before extending the upper forming punch into the forming hole from above, short-cut fibers are added to the forming hole on the middle mold. Then, the upper forming punch extends into the forming hole from above. Finally, the combined closed body of the upper mold 7, middle mold, and lower mold 3 is placed on a hot press to form the forming cavity of the balance support. The short-cut fibers can be hot-pressed and cured indoors. After holding pressure and cooling, the top end of the lower ejector pin 2 is made to pass through the lower ejector hole and contact the bottom surface of the middle mold, and the bottom end of the upper ejector pin 8 is made to pass through the upper ejector hole and contact the top surface of the lower mold 3. The press pressure is used to move the lower ejector pin 2 and the upper ejector pin 8 towards each other, thereby separating the upper mold 7, the middle mold and the lower mold 3. Then the balance support 6 in the forming hole can be taken out. The forming tool of the helicopter tail rotor balance support provided in this embodiment has a simple structure, which is convenient for hot pressing the balance support 6 and easy to demold, thereby effectively improving the production efficiency of the balance support 6.

[0051] Specific examples have been used to illustrate the principles and implementation methods of this invention. The descriptions of the above embodiments are only for the purpose of helping to understand the method and core ideas of this invention. Furthermore, those skilled in the art will recognize that, based on the ideas of this invention, there will be changes in the specific implementation methods and application scope. Therefore, the content of this specification should not be construed as a limitation of this invention.

Claims

1. A forming tool for a tail rotor blade balance support of a helicopter, characterized in that: The utility model relates to a mould, including upper mould, middle mould, lower mould, upper stripper plate and lower stripper plate, the top surface of lower mould is seted up and is limited recess, the bottom surface of limited recess has lower forming male die, the bottom surface of limited recess is seted up and has a plurality of lower ejection hole, each lower ejection hole is around lower forming male die setting, middle mould can be placed in limited recess, the upper surface of middle mould is seted up and has forming hole, the upper surface of lower mould and middle mould is placed in the upper of upper mould, the bottom surface of upper mould has upper forming male die, the bottom surface of upper mould is seted up and has a plurality of upper ejection hole, each upper ejection hole is around upper forming male die setting, lower forming male die can from the lower of forming hole and advance into forming hole, upper forming male die can from the upper of forming hole and advance into forming hole, the top surface of lower forming male die, the bottom surface of upper forming male die and the inside wall of forming hole surround the forming chamber of balance support, lower stripper plate is placed in the lower of lower mould, lower stripper plate is fixed and is arranged with a plurality of lower ejection pin, the number of lower ejection pin is equal to the number of lower ejection hole, lower ejection pin and lower ejection hole one to one, the top end of lower ejection pin can pass through lower ejection hole, the top end of lower ejection pin can be contacted with the bottom surface of middle mould, upper stripper plate is placed in the upper of upper mould, upper stripper plate is fixed and is arranged with a plurality of upper ejection pin, the number of upper ejection pin is equal to the number of upper ejection hole, upper ejection pin and upper ejection hole one to one, the bottom end of upper ejection pin can pass through upper ejection hole, the top end of upper ejection pin can be contacted with the top surface of lower mould.

2. A forming tool for a tail rotor blade balance support of a helicopter according to claim 1, characterized in that: The first demolding gap is left between the outer side wall of the middle mold and the inner side wall of the limiting recess.

3. A forming tool for tail rotor blade balance bushes for a helicopter according to claim 2, characterised in that: The second demolding gap is left between the outer side wall of the lower forming male die and the inner side wall of the forming hole, and the third demolding gap is left between the outer side wall of the upper forming male die and the inner side wall of the forming hole.

4. The forming tool for a tail rotor blade balance support of a helicopter according to claim 1, characterized in that: The first rounded corner part is arranged at the connection between the bottom surface of the middle mold and the inner side wall of the forming hole, and the second rounded corner part is arranged at the connection between the top surface of the middle mold and the inner side wall of the forming hole.

5. The forming tool for a tail rotor blade balance support of a helicopter according to claim 1, characterized in that: The middle mold comprises a middle left mold and a middle right mold, a left forming groove is arranged on the right side surface of the middle left mold, and a right forming groove is arranged on the left side surface of the middle right mold.

6. A forming tool for a tail rotor blade balance support of a helicopter according to claim 5, characterized in that: The middle left mold and the middle right mold are combined to form the middle mold, and the left forming groove and the right forming groove are combined to form the forming hole.

7. A forming tool for a tail rotor blade balance support of a helicopter according to claim 1, characterized in that: The lower stripper plate is threadedly connected with the lower ejection pin.

8. A forming tool for a tail rotor blade balance support of a helicopter according to claim 7, characterized in that: The upper stripper plate is threadedly connected with the upper ejection pin.

9. The forming tool for a tail rotor blade balance support of a helicopter according to claim 1, characterized in that: The number of the lower forming male dies is two, the number of the forming holes arranged on the middle mold is two, and the number of the upper forming male dies is two.

10. A method for forming a helicopter tail rotor blade balance support, comprising using a forming tool for a helicopter tail rotor blade balance support as described in any one of claims 1-9 to manufacture the helicopter tail rotor blade balance support, characterized in that: The number of the lower forming male dies is two, the number of the forming holes arranged on the middle mold is two, and the number of the upper forming male dies is two. The utility model relates to a mould, including following steps: Step one: preheat upper mould, middle mould and lower mould; Step two: place the middle mold in the limiting recess on the lower mold, and make the lower forming male die advance into the forming hole from the lower side of the forming hole; Step three: add chopped fibers into the forming hole on the middle mold; Step four: place the upper mold above the lower mold and the middle mold, and make the upper forming punch extend into the forming hole from above the forming hole; Step five: place the upper mold, the middle mold and the lower mold combined closed body obtained in step four on the hot press for pressurization and heating, then keep pressure and cool; Step six: place the lower stripper plate on the press, place the upper mold, the middle mold and the lower mold combined closed body above the lower stripper plate, and make the top end of the lower ejector pin contact the bottom surface of the middle mold through the lower ejector hole, place the upper stripper plate above the upper mold, the middle mold and the lower mold combined closed body, and make the bottom end of the upper ejector pin contact the top surface of the lower mold through the upper ejector hole; Step seven: start the press, separate the upper mold, the middle mold and the lower mold, and take out the balancing support in the forming hole.

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