CN101214510B

CN101214510B - Blind hole internal gear precision forming method and internal tooth forming mold

Info

Publication number: CN101214510B
Application number: CN2008100193916A
Authority: CN
Inventors: 杨海平; 陈爱华; 靳天龙
Original assignee: JIANGSU SUNWAY GROUP CO Ltd
Current assignee: Jiangsu Sunway Group Feida Co., Ltd.
Priority date: 2008-01-08
Filing date: 2008-01-08
Publication date: 2010-10-13
Anticipated expiration: 2028-01-08
Also published as: CN101214510A

Abstract

The invention provides a blind hole internal gear fine forming method and an internal gear forming die relating to the metal machinery processing and metal pressing fields of no cutting. The technical steps includes: computer simulation analyzing to study out a process forming scheme-baiting to manufacture roughs-surface intenerating and lubricating processing-fine forming-cutting off redundant part. A convex die profile of an internal gear forming die is corrected according to a gear precision grade tolerance belt and the gear precision is 6 to 5 grade. The surface roughness of the convex die is smaller than 0.5 micron. The thickness of a surface nanometer coat is 0.002 to 0.004 millimeter. A die entrance angle of at end surface of the gear is transited by a semi-arc. An effective width of a minor first flank is between 1.5 and 3 millimeter. A double surface back gap of the minor first flank is 0.3 millimeter smaller than the minor first flank by average. The transition cone angle between the minor first flank of the convex die and a basic die is 3 to 6 degrees. A concave die is formed through interference pressure distribution by adopting 2 to 3 layers of compound dies. The magnitude of interference is 0.4 to 0.5 percent of a matched dimension of a die. The invention has the advantages of short technique line, high manufacture efficiency, good consistence of the gear precision and high intensity.

Description

Blind hole internal gear precision forming method and internal tooth forming mold

Technical field

The present invention relates to not have cutting metal mechanism processing substantially, the plastic precise forming method and the internal tooth forming mold of metal stamping field, especially blind hole internal gear machine components.

Background technology

At present, the gear machine cutting working method is mainly adopted in the manufacturing of blind hole internal gear.There is following defective in this manufacture method: (one) process route is longer, generally will forge multiple tracks machining processes such as base, thick finish turning processing, Gear Shaping; (2) production efficiency is lower; (3) uniformity of the accuracy of gear is relatively poor; Must leave grinding undercut during (four) owing to Gear Shaping, product structure is increased, intensity reduces.

Summary of the invention

The objective of the invention is to overcome the drawback of existing blind hole internal gear machine cut processing method, provide a kind of process route short, production efficiency height, accuracy of gear high conformity, blind hole internal gear precision forming method and internal tooth forming mold that intensity is high.

Technical solution of the present invention is:

The processing step of blind hole internal gear precision forming method is: (one) simulation analysis of computer, draft substep shaping scheme; (2) blanking base; (3) the softening and lubricated in surface; (4) precision form; (5) excision redundance.

Described blanking base comprises 1. peeling processing, other steel except that special-purpose cold forging steel is carried out peeling process, the groove of removal steel surface and the crackle that stays when rolling; 2. according to shape of product, material plasticity base, blank diameter is 2/3rds to 3/4ths of a product maximum gauge, billet weight be product weight 105～115% between.

1. the softening and lubricated in described surface comprises blank is placed in the vacuum heat treatment furnace, be heated to 700～720 degree Celsius, be incubated 180～300 minutes spheroidizings, furnace temperature is reduced to 530～580 degree Celsius, the air cooling of coming out of the stove makes blank hardness less than rockwell b scale chi 85 MPas; 2. carry out the ball blast surface treatment; 3. under 80～100 degree temperature Celsius, carry out the phospholeum processing.

Described precision form refers to the blank of and lubricated softening through the surface is placed on the mold center position, adopts cold forging forcing press or hydraulic press oppositely to push the one or many Plastic Forming.

The blind hole internal gear internal tooth forming mold mainly is made up of punch and die assembly, the outline of die assembly mould shape and blind hole internal gear product is corresponding, the interior profile geometry and the end surface shape of punch die body shape and blind hole internal gear product are corresponding, it is characterized in that: the punch flank profil is revised according to accuracy of gear grade tolerance range, from the gear compound graduation circle to Gear Root the circle progressively by standard size to minimum limit of size transition, profile accuracy is 6～5 grades, the convex mould surface roughness is less than 0.5 micron, 0.002～0.004 millimeter of convex mould surface nano coating thickness, the modular angle of going into punch increment face adopts semi arch excessive, punch land effective width is between 1.5～3 millimeters, crack, the two-sided back of land is even littler 0.3 millimeter than land, and punch land and basic mode transition cone angle are 3～6 degree; The die assembly adopts 2～3 layers of combination die, and interference is joined pressure and formed, and the magnitude of interference is 0.4～0.5% of a mould fit dimension.

Advantage of the present invention is: (one) adopts cold forging backward extrusion technology processing blind hole internal gear, because cold forging carries out pressure processing at normal temperatures, the metal surface can not produce oxidation, therefore can produce metal parts near net shape, the material and the energy have been saved, reduce manufacturing procedure and equipment, increased substantially production efficiency.(2) because processing products obtained therefrom metal streamline is pressed the profile geometry distribution, so the product mechanical strength is enhanced.(3) because the form of gear tooth partly realizes not having machining, so accuracy of gear high conformity.(4) because the form of gear tooth partly realizes not having machining, and the modular angle of going into punch increment face adopts semi arch excessive, be that arc size is less than the design of gears chamfer dimesion, therefore need not to stay grinding undercut during the processing blind hole internal gear, the gear total length effectively meshes, reduce product structure, improved product strength.

Description of drawings

Fig. 1 is a blind hole internal gear internal tooth forming mold working state schematic representation of the present invention.

Fig. 2 is a punch tooth Profile Design schematic diagram of the present invention.

Fig. 3 is punch margin width of the present invention and transition cone angle schematic diagram.

Fig. 4 is that punch K of the present invention is to land profile of tooth enlarged drawing.

Among the figure: 1, blind hole internal gear product, 2, blank, 3, punch, 4, the die assembly, 5, the punch tooth curve, 6, the flank profil minimum limit of size, 7, the gear compound graduation circle, 8, the Gear Root circle, 9, the transition cone angle, 10, the increment face goes into modular angle, 11, basic mode.

The specific embodiment

Be fabricated to example with the JY60 internal gear with 20 Cr-Mn-Ti materials.

Processing step with 20 Cr-Mn-Ti material precision form JY60 internal gears is:

(1) simulation analysis of computer is drafted substep shaping scheme;

(2) blanking base;

1. adopting diameter is 65 millimeters 20 Cr-Mn-Ti round steel, cutting stock weight 476 grams;

2. with blank (2) diameter car to 64 millimeter;

(3) the softening and lubricated in surface;

1. blank (2) is placed in the heat-treatment furnace, is heated to 770 degree Celsius, be incubated 240 minutes spheroidizings, furnace temperature is reduced to 550 degree Celsius, and the air cooling of coming out of the stove makes blank (2) hardness less than rockwell b scale chi 85 MPas;

2. blank (2) is carried out the ball blast surface treatment;

3. phospholeum processing;

I ceaselessly rolls blank (2) pickling about 10 minutes in 10～20% dilute sulfuric acid aqueous solution of 50～60 degree Celsius;

II cleaned 3～4 minutes with circulating water;

III rolling phosphatization 10～16 minutes in 80～100 degree phosphatization liquid Celsius;

IV cleans with circulating water;

V washed 1～2 minute with 80～100 degree hot water smelts Celsius;

VI spends the saponification of rolling in the saponification liquors Celsius 80～100

VII washed 1～2 minute with 80～100 degree hot water smelts Celsius;

(4) precision form is placed on blank (2) softening through the surface and lubricated in the die assembly (4), and punch (3) oppositely pushes by cold forging forcing press or hydraulic press, the one or many Plastic Forming;

(5) the excision redundance excises the excess stock that flows out from blind hole internal gear product (1) end face with machining mode, and finishes all the other processing according to designing requirement.

The blind hole internal gear internal tooth forming mold is made up of main punch (3) and die assembly (4), the outline of the die body shape of die assembly (4) and blind hole internal gear product (1) is corresponding, and the interior profile geometry and the end surface shape of the die body shape of punch (3) and blind hole internal gear product (1) are corresponding.The tooth curve (5) of punch (3) is revised according to accuracy of gear grade tolerance range, justify from gear compound graduation circle (7) to Gear Root (8) progressively by standard size to the minimum limit of size (6) transition.Profile accuracy is 6～5 grades, and punch (3) surface roughness is less than 0.5 micron, 0.002～0.004 millimeter of punch (3) nano surface coating layer thickness.The modular angle (10) of going into punch (3) increment face adopts semi arch excessive, and arc radius is less than the design of gears chamfering.Punch (3) land effective width is between 1.5～3 millimeters, and the crack inwardly dwindles 0.15 millimeter than land is even behind the land, and punch (3) land and basic mode (11) transition cone angle (9) are 3～6 degree; Die assembly (4) adopts the interference of three layers of shrink ring combination die to join pressure and forms, and the magnitude of interference is 0.4～0.5% of a product design size.

Claims

1. blind hole internal gear internal tooth forming mold, it mainly is made up of punch and die assembly, the outline of die assembly mould shape and blind hole internal gear product is corresponding, the interior profile geometry and the end surface shape of punch die body shape and blind hole internal gear product are corresponding, it is characterized in that: the punch flank profil is revised according to accuracy of gear grade tolerance range, from the gear compound graduation circle to Gear Root the circle progressively by standard size to minimum limit of size transition, profile accuracy is 6～5 grades, the convex mould surface roughness is less than 0.5 micron, 0.002～0.004 millimeter of convex mould surface nano coating thickness, punch increment face is gone into modular angle and is adopted the semi arch transition, punch land effective width is between 1.5～3 millimeters, crack, the two-sided back of land is even littler 0.3 millimeter than land, and punch land and basic mode transition cone angle are 3～6 degree; The die assembly adopts 2～3 layers of combination die, and interference is joined pressure and formed, and the magnitude of interference is 0.4～0.5% of a mould fit dimension.