Special-shaped hole helical gear forming die

Abstract

The utility model relates to the technical field of gear forming die structures, in particular to a special-shaped hole helical gear forming die, which is provided with an upper punch, a middle die, a lower punch and a core rod, and is characterized in that an inner helical tooth groove is arranged on the inner wall of the middle die, the upper punch is arranged above the middle die, a positioning round hole is arranged on the lower end face of the upper punch, and the lower end face of the lower punch is provided with an inner helical tooth groove. The lower punch is arranged below the middle die, outer oblique tooth grooves matched with the oblique tooth grooves are formed in the outer wall of the lower punch and the outer wall of the upper punch, a core rod penetrating hole is formed in the axis position of the lower punch, the core rod is arranged below the lower punch, the upper end of the core rod is connected with a plug matched with a positioning round hole of the upper punch, and the core rod penetrating hole is a special-shaped hole. And the outer wall of the core rod is inserted into the special-shaped hole in a matching manner. The forming device has the advantages of simple structure, good forming effect, high forming efficiency, cost saving and the like.

Description

Technical Field

[0001] The utility model relates to the technical field of gear forming die structures, and specifically relates to a special-shaped hole helical gear forming die with a simple structure, good forming effect, high forming efficiency and cost saving. Background Technique

[0002] As is well known, powder metallurgy helical gears are conventional transmission parts in electric circular saw tools, and the usage amount accounts for more than 30% of the entire electric circular saw industry. Their design directly affects the quality of products. Therefore, reasonable design is very important for service life.

[0003] At present, the middle of the existing helical gears is a special-shaped hole, and it is very difficult to prepare them by powder metallurgy technology. The general preparation method is to prepare and form by powder metallurgy method, and then cut and polish the special-shaped hole inside the helical gear through cutting technology. However, during the cutting and polishing process, the center of the special-shaped hole may not correspond to the center of the helical gear. Therefore, the rejection rate of making helical gears is high, the cost is high, the forming effect is not good, and the forming efficiency is low. Summary of the Invention

[0004] The purpose of the utility model is to solve the deficiencies of the above-mentioned existing technologies, and provide a special-shaped hole helical gear forming die with a simple structure, good forming effect, high forming efficiency and cost saving.

[0005] The technical solution adopted by the utility model to solve its technical problems is:

[0006] A special-shaped hole helical gear forming die is provided with an upper punch, a middle die, a lower punch and a core rod. The feature is that an internal helical tooth groove is provided on the inner wall of the middle die. The upper punch is arranged above the middle die, and a positioning round hole is provided on the lower end surface of the upper punch. The lower punch is arranged below the middle die, and external helical tooth grooves matching with the helical tooth groove are provided on the outer wall of the lower punch and the outer wall of the upper punch. A core rod through hole is provided at the axis position of the lower punch. The core rod is arranged below the lower punch, and the upper end of the core rod is connected with a plug matching with the positioning round hole of the upper punch. The core rod through hole is a special-shaped hole, and the outer wall of the core rod is inserted into the special-shaped hole in a matching manner.

[0007] The upper punch of the utility model includes an upper punch pad, an upper punch cover and an upper punch head. The cross section of the upper punch head is T-shaped. An annular groove is provided on the upper end surface of the upper punch cover, and a through hole is provided at the bottom of the annular groove. The horizontal part of the T-shaped upper punch head is arranged in the annular groove and is connected with the upper punch pad through a rotating part. The vertical part of the T-shaped upper punch head passes through the through hole and is inserted into the middle die. The upper punch cover is fixed on the upper punch pad through bolts.

[0008] The lower punch of the present utility model includes a lower punching pad, a lower punching cover, and a lower punching head. The cross-section of the lower punching head is T-shaped. The lower end surface of the lower punching cover is provided with an annular groove, and a perforation is provided at the bottom of the annular groove. The horizontal part of the T-shaped lower punching head is arranged in the annular groove and is connected to the lower punching pad through a rotating part. The vertical part of the T-shaped lower punching head passes through the perforation and is inserted into the middle die. The lower punching cover is fixed to the lower punching pad by bolts. The core rod perforation is arranged at the axial positions of the lower punching pad, the lower punching head, and the rotating part.

[0009] The core rod of the present utility model includes a core rod pressing pad, a core rod pressing cover, and a core rod pressing head. The cross-section of the core rod pressing head is T-shaped. The lower end surface of the core rod pressing cover is provided with an annular groove, and a perforation is provided at the bottom of the annular groove. The horizontal part of the T-shaped core rod pressing head is arranged in the annular groove and is connected to the core rod pressing pad through a rotating part. The vertical part of the T-shaped core rod pressing head passes through the perforation and is inserted into the core rod perforation of the lower punch. The core rod pressing cover is fixed to the core rod pressing pad by bolts.

[0010] The rotating part of the present utility model is a bearing or a spiral piece that can automatically rotate, and the upper punching head, the lower punching head, or the core rod pressing head is rotated by the bearing or the spiral piece.

[0011] The spiral piece of the present utility model is provided with spiral grooves on its surface, and spiral blocks are provided on the groove surfaces of the spiral grooves. The spiral blocks are respectively connected to the end surfaces of the upper punching head, the lower punching head, or the core rod pressing head, and the rotation of the spiral blocks in the spiral grooves realizes the rotation of the upper punching head, the lower punching head, or the core rod pressing head.

[0012] The lower end surface of the upper punching head of the present utility model is provided with a transition groove, which is coaxial with the positioning round hole, and the core rod plug is inserted into the positioning round hole through the transition groove.

[0013] Due to the adoption of the above structure, the present utility model has the advantages of simple structure, good forming effect, high forming efficiency, and cost saving. Description of the Drawings

[0014] Figure 1 is the structural schematic diagram of the present utility model.

[0015] Figure 2 is the product forming diagram of the present utility model with a square hole as the special-shaped hole. Detailed Embodiment

[0016] The present utility model will be further described below in conjunction with the drawings:

[0017] As shown in the attached drawings, a forming die for a special-shaped hole helical gear is provided with an upper punch, a middle die 1, a lower punch and a core rod. It is characterized in that an internal helical tooth groove is provided on the inner wall of the middle die 1. The upper punch is arranged above the middle die 1, and a positioning round hole 2 is provided on the lower end face of the upper punch. The lower punch is arranged below the middle die 1, and external helical tooth grooves that cooperate with the helical tooth groove are provided on the outer wall of the lower punch and the outer wall of the upper punch. A core rod perforation is provided at the axis position of the lower punch. The core rod is arranged below the lower punch, and the upper end of the core rod is connected with a plug 3 that cooperates with the positioning round hole 2 of the upper punch. The core rod perforation is a special-shaped hole, and the outer wall of the core rod is inserted into the special-shaped hole in a matching manner.

[0018] Furthermore, the upper punch includes an upper punch pad 4, an upper punch cover 5, and an upper punch head 6. The cross-section of the upper punch head 6 is in a T shape. An annular groove is provided on the upper end face of the upper punch cover 5, and a perforation is provided at the bottom of the annular groove. The horizontal part of the T-shaped upper punch head 6 is arranged in the annular groove and is connected with the upper punch pad 4 through a rotating part 8. The vertical part of the T-shaped upper punch head 6 passes through the perforation and is inserted into the middle die 1. The upper punch cover 5 is fixed on the upper punch pad 4 through bolts.

[0019] Furthermore, the lower punch includes a lower punch pad 9, a lower punch cover 10, and a lower punch head 11. The cross-section of the lower punch head 11 is in a T shape. An annular groove is provided on the lower end face of the lower punch cover 10, and a perforation is provided at the bottom of the annular groove. The horizontal part of the T-shaped lower punch head 11 is arranged in the annular groove and is connected with the lower punch pad 9 through a rotating part 8. The vertical part of the T-shaped lower punch head 11 passes through the perforation and is inserted into the middle die 1. The lower punch cover 10 is fixed on the lower punch pad 9 through bolts. The core rod perforation is provided at the axis position of the lower punch pad 9, the lower punch head 11, and the rotating part 8.

[0020] Furthermore, the core rod includes a core rod pad 12, a core rod cover 13, and a core rod head 14. The cross-section of the core rod head 14 is in a T shape. An annular groove is provided on the lower end face of the core rod cover 13, and a perforation is provided at the bottom of the annular groove. The horizontal part of the T-shaped core rod head 14 is arranged in the annular groove and is connected with the core rod pad 12 through a rotating part 8. The vertical part of the T-shaped core rod head 14 passes through the perforation and is inserted into the core rod perforation of the lower punch. The core rod cover 13 is fixed on the core rod pad 12 through bolts.

[0021] Furthermore, the rotating part 8 is a bearing or a spiral piece that can automatically rotate, and the self-rotation of the upper punch head 6, the lower punch head 11, or the core rod head 14 is realized through the bearing or the spiral piece.

[0022] Furthermore, spiral grooves are provided on the surface of the spiral piece, and spiral blocks are provided on the groove surface of the spiral grooves. The spiral blocks are respectively connected to the end faces of the upper punch head 6, the lower punch head 11, or the core rod head 14, and the rotation of the upper punch head 6, the lower punch head 11, or the core rod head 14 is realized by the spiral blocks rotating in the spiral grooves.

[0023] Further, a transition groove 15 is provided on the lower end surface of the upper punch head 6. The transition groove 15 is coaxial with the positioning round hole 2, and the mandrel plug 3 is inserted into the positioning round hole 2 through the transition groove 15.

[0024] The above-mentioned special-shaped hole is a non-circular hole. Figure 2 The special-shaped hole in [reference] is a square hole 16, and the hole formed by the plug in the transition groove is a round hole 7.

[0025] When the utility model is in use, the lower end of the upper punch head 6 is inserted into the middle die 1, the lower punch head 11 is inserted into the middle die 1, the mandrel plug 3 passes through the lower punch head 11 and then is inserted into the upper punch head 6. A helical gear forming cavity with a special-shaped hole is formed among the lower punch head 11, the middle die 1, the mandrel press head 14 and the upper punch head 6. When demolding, the upper punch head 6 is lifted upward. Since the upper punch head 6 is provided with an external helical tooth groove, it rotates and disengages during the upward pulling process. At the same time, the lower punch head 11 and the mandrel punch head move upward. During the upward movement, the lower punch head 11 rotates and moves upward under the action of the external helical tooth groove. During the rotation process, since the cross section of the mandrel is a special-shaped structure, therefore, the mandrel press head 14 rotates along with the lower punch head 11, thereby driving the formed product to rotate synchronously and ejecting the product out of the middle die 1. After ejection, since there is a protrusion formed by the transition groove 15 above the formed product, only end face grinding is needed, and then the helical gear with a special-shaped hole is completed. Since the transition groove 15 is provided, it can ensure that the special-shaped hole of the helical gear can penetrate the axial direction of the helical gear, and at the same time, it can also position the mandrel plug 3, so that the mandrel plug 3 does not drive the upper punch head 6 to rotate while rotating. Therefore, the formed product only needs to be ground. Due to the adoption of the above structure, the utility model has the advantages of simple structure, good forming effect, high forming efficiency and cost saving.

Claims

1. A special-shaped hole helical gear forming die, comprising an upper punch, a middle die, a lower punch and a core rod, characterized in that The inner wall of the middle die is provided with inner oblique teeth, the upper punch is arranged above the middle die, the lower end face of the upper punch is provided with a positioning circular hole, the lower punch is arranged below the middle die, the outer wall of the lower punch and the outer wall of the upper punch are provided with outer oblique teeth that match the oblique teeth, a core rod through hole is provided at the axial position of the lower punch, the core rod is arranged below the lower punch, the upper end of the core rod is connected to a plug that matches the positioning circular hole of the upper punch, the core rod through hole is a special-shaped hole, and the outer wall of the core rod is matched with the special-shaped hole for insertion.

2. The special-shaped hole helical gear forming die according to claim 1, characterized in that The upper punch includes an upper punch pad, an upper punch cover, and an upper punch head. The cross-section of the upper punch head is T-shaped. The upper end surface of the upper punch cover is provided with an annular groove, and the bottom of the annular groove is provided with a through hole. The transverse part of the T-shaped upper punch head is arranged in the annular groove and connected to the upper punch pad via a rotating part. The vertical part of the T-shaped upper punch head passes through the through hole and is inserted into the middle mold. The upper punch cover is fixed to the upper punch pad by bolts.

3. The special-shaped hole helical gear forming die according to claim 1, characterized in that The lower punch includes a lower punch pad, a lower punch cover, and a lower punch head. The cross-section of the lower punch head is T-shaped. The lower end surface of the lower punch cover is provided with an annular groove, and the bottom of the annular groove is provided with a through hole. The transverse part of the T-shaped lower punch head is arranged in the annular groove and connected to the lower punch pad through a rotating part. The vertical part of the T-shaped lower punch head passes through the through hole and is inserted into the middle mold. The lower punch cover is fixed to the lower punch pad by bolts, and the core rod through hole is arranged at the axial position of the lower punch pad, the lower punch head, and the rotating part.

4. The special-shaped hole helical gear forming die according to claim 1, characterized in that The mandrel comprises a mandrel pressure pad, a mandrel pressure cover and a mandrel pressure head. The cross section of the mandrel pressure head is T-shaped. The lower end surface of the mandrel pressure cover is provided with an annular groove, and the bottom of the annular groove is provided with a through hole. The transverse part of the T-shaped mandrel pressure head is arranged in the annular groove and connected to the mandrel pressure pad via a rotating part. The vertical part of the T-shaped mandrel pressure head passes through the through hole and is inserted into the through hole of the lower punch mandrel. The mandrel pressure cover is fixed to the mandrel pressure pad by bolts.

5. A special-shaped hole helical gear forming die according to claim 2, 3 or 4, characterized in that The rotating part is a bearing or a spiral sheet that can rotate automatically, and the upper punch head, the lower punch head or the core rod punch head can rotate automatically through the bearing or the spiral sheet.

6. The special-shaped hole helical gear forming die according to claim 5, characterized in that The spiral sheet has a spiral groove on its surface, and a spiral block on its groove surface. The spiral blocks are respectively connected to the end faces of the upper punch head, the lower punch head or the core rod punch head. The spiral block rotates in the spiral groove to realize the rotation of the upper punch head, the lower punch head or the core rod punch head.

7. The special-shaped hole helical gear forming die according to claim 1, characterized in that A transition groove is arranged on the lower end surface of the upper punch head, the transition groove is coaxial with the positioning circular hole, and the core rod plug is inserted into the positioning circular hole through the transition groove.

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