External gear single-way speed-reducing device external toothing preparation method and mould thereof
The present invention relates to the manufacture method of the external gear single-way speed-reducing device external toothing of using on a kind of automobile starter, and realize the particular manufacturing craft that this method is required.
External toothing is a vitals on the external gear single-way speed-reducing device, by external toothing the driving torque of actuating motor is passed to the engagement shaft of starter, realizes the start-up function of starter.The wheel blank that utilizes cold conditions pressure processing manufacturing band profile of tooth is the method for the manufacturing external toothing used always, for example the clear 62-112829 of Japanese documentation divides technology and the mould of having opened a kind of wheel blank with process for stamping manufacturing band profile of tooth, and this method utilizes a procedure just can finish the wheel blank making.But when manufacturing external toothing,, make external toothing be difficult to a drawing, cause this method not implement because external gear single-way speed-reducing device external toothing has comparatively complicated external and internal compositions.
Chinese patent 92112696 discloses a kind of cold-drawing method of the wheel blank with profile of tooth, it is by the progressively distortion of mould, blank progressively is out of shape, when yet this method is used for the manufacturing of isolator external toothing, exist that mould complexity, work efficiency are low, the defective of machining accuracy difference, especially easily cause the eccentric error of external toothing.Therefore the processing and fabricating of present this external gear single-way speed-reducing device external toothing generally all adopts following process: utilize mould with base cold moudling, after heat treatment, form the crude green body of external toothing, mill out the corresponding number of teeth with milling machine at the outer surface of crude green body again, improve the machining accuracy of isolator external toothing thus.But because this processing method work efficiency is low, cause production cost higher, be unfavorable for enterprise's raising productivity effect.
Summary of the invention
Purpose of the present invention is exactly the defective according to above-mentioned processing method, a kind of method of quick production and processing isolator external toothing in batch is provided and is the needed corresponding mould of this method of realization.
The present invention realizes by following manner:
Raw material are processed into the stock of thick shape according to the target component shape need, technological requirement according to cold mould extruding, treating turned blank anneals, softens and handle, make it hardness in the HB110-150 scope, carry out descale, pickling, cleaning subsequently, and saponification liquor in saponification, at last by cold extrusion on forcing press, form the crude green body of the isolator external toothing gear of band star-wheel tooth, insert the post forming mould, push once more, finish the moulding of external toothing appearance gear by forcing press, through metalworking and heat treatment, finish the making of external toothing.
Above-mentioned cold mould extrusion process process is finished in corresponding mould, this mould by punch, squeeze external tooth mould, die cushion block, push rod fairlead, constitute, wherein be combined into bed die by crowded external tooth mould and die cushion block, the inwall bottom of squeezing the external tooth mould be provided with squeeze outside teeth groove, the diameter of bore top of squeezing the external tooth mould equates with the punch external diameter, form matching relationship, push rod then cooperates activity by the push rod fairlead with bed die, on the axis of squeezing the external tooth mold cavity, be provided with the star-wheel punch, and dock with push rod by plug.
The inwall that squeezes the external tooth mould be provided with squeeze outside teeth groove;
On the star-wheel punch, have with the star-wheel shape of workpiece to be processed form fit outstanding.
Because technology efficiency provided by the present invention ground control processing precision of products, have the work efficiency height, moulding is fast, therefore the advantage that production cost is low can make manufacturing enterprise improve productivity effect greatly.
Description of drawings
Fig. 1 is an isolator external toothing structural representation;
Fig. 2 is die assembly figure;
Fig. 3 is for squeezing external tooth mode structure schematic diagram;
Fig. 4 star-wheel punch structure schematic diagram.
The specific embodiment
One, at first raw material to be processed are processed into the stock of thick shape according to the target component shape need, technological requirement according to cold mould extruding, treating turned blank anneals, the softening processing, make it hardness in the HB110-150 scope, carry out descale subsequently, pickling, clean, and saponification liquor Zhong Sudsization, then by cold mould extruding on forcing press, extrusion has the crude green body of the isolator external toothing gear of star-wheel base and star-wheel internal tooth 9, again this crude green body is inserted the post forming mould, push for the second time, finish the moulding of external toothing appearance gear 8 by forcing press, through processing and heat treatment, finish the making of isolator external toothing.
In order to realize said process, the present invention also provides a kind of assembling die, this group mould is made of punch 1, crowded external tooth mould 4, die cushion block 5, push rod 7, push rod fairlead 6, wherein be combined into bed die with die cushion block 5 by crowded external tooth mould 4, the inwall bottom of squeezing external tooth mould 4 be provided with squeeze outside teeth groove 10, the diameter of bore top of squeezing external tooth mould 4 equates with punch 1 external diameter, form matching relationship, 7 of push rods pass through push rod fairlead 6 and cooperate activity with bed die, on the axis of squeezing external tooth mould 4 inner chambers, be provided with star-wheel punch 3, and dock with push rod 7 by plug 2.After the isolator external toothing gear crude green body of being made by last process is sent into mould, cooperate with star-wheel internal tooth 9 on the isolator external toothing wheel blank by star-wheel punch 3, make isolator external toothing gear crude green body to be processed can stably be fixed on the star-wheel punch 3, and pressing down along with punch 1, isolator external toothing gear crude green body is displaced downwardly to fixed bit with star-wheel punch 3 and plug 2, squeeze out the outer surface tooth of isolator external toothing, upwards move by push rod 7 more at last, release the product that machines.
Two, on the basis of the foregoing description, for can be effectively the fixing middle shaft position of isolator external toothing wheel blank in mould, according to the 9 peculiar eccentric curved surface features of the star-wheel internal tooth on the isolator external toothing wheel blank, the star-wheel surface on the star-wheel punch 3 also is designed to external tooth and wears eccentric curved surface shape 11.