CN103817307B

CN103817307B - A kind of method solving CVT electrodeless variable-speed tank shell deep-cavity thin-wall reinforcement end face cold shut

Info

Publication number: CN103817307B
Application number: CN201410013646.3A
Authority: CN
Inventors: 张辉; 姜峰
Original assignee: JIANGSU XUHANG TECHNOLOGY CO LTD
Current assignee: Xuzhou Jincheng Precision Manufacturing Co ltd
Priority date: 2014-01-13
Filing date: 2014-01-13
Publication date: 2015-12-30
Anticipated expiration: 2034-01-13
Also published as: CN103817307A

Abstract

The invention discloses a kind of method solving CVT electrodeless variable-speed tank shell deep-cavity thin-wall reinforcement end face cold shut, first revise the position for die casting deep-cavity thin-wall reinforcement (2) end face on CVT stepless gearbox housing mould, reserve and this end face can be made to increase the space of 3-5mm compared with design size; Next utilizes amended die casting CVT electrodeless variable-speed tank shell, deep-cavity thin-wall reinforcement (2) end face of gained naturally comparatively design size raise to some extent; Finally by milling cast gate operation, the part milling that deep-cavity thin-wall reinforcement (2) end face exceeds design size is removed.The present invention produces position by transfer cold shut, is moved to the position of inessential or follow-up removal, thoroughly solves the problem of reinforcement cold shut defects, to final products without any quality influence.

Description

A kind of method solving CVT electrodeless variable-speed tank shell deep-cavity thin-wall reinforcement end face cold shut

Technical field

The present invention relates to aluminium alloy compression casting field, be specifically related to a kind of method mainly for CVT electrodeless variable-speed tank shell deep-cavity thin-wall reinforcement end face cold shut defects, foundry goods can be solved because of end face cold shut by the method at all and cause the problem of scrapping.

Background technology

In order to adapt to the trend of automotive light weight technology, the case of transmission that current CVT stepless gearbox is used and clutch housing all adopt aluminium alloy high pressure to cast, stepless gearbox certainly will cause internal structure quite complicated to export impayable cornering ability, shell dimension is very large, wall thickness is very thin, especially at driving wheel hop, in order to strengthen the stability of four oil circuit controllers, the reinforcement of an orthodrome transition need be set at the core of housing, although this reinforcement greatly improves the power transmission stability of stepless gearbox, reduce noise, but cause more difficult technical barrier to thus the extrusion process of housing, conventional high-pressure forging type is used to be difficult to ensure that the orthodrome reinforcement of deep-cavity thin-wall there will not be defects of die casting.

For the case of transmission in CVT stepless gearbox, as shown in Figure 1, the size of CVT case of transmission 1 is larger, complex structure, especially the deep-cavity thin-wall reinforcement 2 in the middle of housing is among the dark chamber of mould, and not only deep-cavity thin-wall reinforcement 2 is in arc-shaped, and arc radius reaches 90mm, and deep-cavity thin-wall reinforcement 2 degree of depth is 140mm, wall thickness but only has 3mm.In press casting procedure, the end face of this deep-cavity thin-wall reinforcement 2 very easily forms cold shut defects, i.e. end face handing-over the smooth of the edge, inner formation gap or pit.Crack cause mainly contains two: the area on the one hand due to the lower mould of molten metal contacts temperature is comparatively large, and cause molten metal temperature sharply to reduce, its mobility decreases; Charging aperture charging simultaneously from deep-cavity thin-wall reinforcement 2 both sides on the other hand, two molten metals converge at deep-cavity thin-wall reinforcement 2 place, converge the air very easily wrapping up in the middle of liquid and cannot discharge in time.Under comprehensive function both ways, as shown in Figure 1, deep-cavity thin-wall reinforcement 2 end face at A place, home position will produce cold shut defects not of uniform size, and the cold shut degree of depth at this place generally all can be greater than 1.5mm, exceed the allowance at this place, cause product to be scrapped because of processing casting skin.Learn according to actual Die Casting experience and qualitative data, the scrap products caused because of reinforcement end face cold shut accounts for the ratio of total waste product more than 1/3, causes the waste of great quality cost.

Above-mentioned reinforcement belongs to the functional form structural design in CVT stepless gearbox, cannot by changing its position or this defect is evaded in moulding, except non-usage vacuum die casting process, but consider that the input of evacuated die-casting process on equipment is huge, and the sealing of mould, the matching problem of die casting machine are had higher requirement, generally produce CVT buncher housing by evacuated die-casting process and do not meet market demands very much.Also some die casting factories are had by designing brand-new mould in prior art, take out slide block and solve aluminium liquid as increased a large amount of sides and fill insufficient and cause the problem of housing cold shut, the effect that this method is used for deep-cavity thin-wall reinforcement is discussed for the present, but add the complexity of module, just increase production cost, at least do not utilize and promote the use of.

In sum, need badly at present and solve the problems referred to above by a kind of easy method, not only without the need to large area amendment mould, less input or do not have for disposable apparatus, and technical process mature and reliable, convenient operation.

Summary of the invention

For above-mentioned how by as far as possible little amendment mould, the technical problem of light labour-saving removing reinforcement cold shut end face, the invention provides a kind of method solving CVT electrodeless variable-speed tank shell deep-cavity thin-wall reinforcement end face cold shut, cause the problem of scrapping to solve foundry goods because of end face cold shut at all.

For achieving the above object, the invention provides a kind of method solving CVT electrodeless variable-speed tank shell deep-cavity thin-wall reinforcement end face cold shut, concrete steps are as follows: for the position of die casting deep-cavity thin-wall reinforcement end face on A, amendment CVT stepless gearbox housing mould, reserve and this end face can be made to increase the space of 3-5mm compared with design size.Further, to the retouching operation of mould, comprising: first adopt the dynamo-electric molding tool of spark machined to the size required, then it is smooth to play the thin reconditioning in position to electricity.

B, utilize amended die casting CVT electrodeless variable-speed tank shell, the deep-cavity thin-wall reinforcement end face of gained naturally comparatively design size raise to some extent.Even if now reinforcement end face creates the cold shut of degree of depth 1.5mm, but its comparatively design size raised 3-5mm, be greater than the degree of depth of cold shut, so the design attitude that cold shut is dark and reinforcement end face is original.

C, by milling cast gate operation, the part milling that deep-cavity thin-wall reinforcement end face exceeds design size removed, then deep-cavity thin-wall reinforcement end face returns to due design size.The size exceeded with end face due to end face cold shut has been removed in the lump, and the reinforcement end face obtained conforms to quality requirements.

To sum up, juche idea of the present invention is obviously different from prior art by means such as complicated improvement moulds, make great efforts the thinking just eliminating deep-cavity thin-wall reinforcement end face cold shut defects when die casting for shell is shaped, then the cold shut defects of reinforcement end face is remained when die casting for shell is shaped, in advance by the minor modifications to mould, raise the position of reinforcement end face forming, thus displaced the position of cold shut defects generation, cold shut defects place is moved to the inessential or follow-up position that can remove, operation is removed again by follow-up milling, easily the position of reinforcement end face cold shut defects is removed.

This method not only to final products without any quality influence, also improve the qualification rate of product greatly, decrease waste, reduce production cost, thus thoroughly solve the problem of reinforcement cold shut defects.And this method is simply small to the amendment of mould, less input or do not have for disposable apparatus, technical process mature and reliable, and convenient operation is cost-saving.Further, the present invention is suitable for CVT case of transmission in CVT electrodeless variable-speed tank shell and clutch housing, also suitablely extends to the deep-cavity thin-wall type die casting position that other need avoid cold shut defects.

Accompanying drawing explanation

Fig. 1 is the structural representation of CVT case of transmission in prior art;

Structure enlarged diagram when Fig. 2 is use the inventive method in A place in Fig. 1.

In figure: 1, CVT case of transmission, 2, deep-cavity thin-wall reinforcement.

Detailed description of the invention

Below in conjunction with accompanying drawing, the invention will be further described.

CVT electrodeless variable-speed tank shell comprises all with CVT case of transmission 1 and the clutch housing of deep-cavity thin-wall reinforcement 2, and existing for the case of transmission 1 in CVT stepless gearbox, solve deep-cavity thin-wall reinforcement end face cold shut defects, concrete steps are as follows.

Before enforcement, the die casting of CVT case of transmission 1 must be revised among a small circle, make the position for die casting deep-cavity thin-wall reinforcement 2 end face on mould, this end face of sening as an envoy to increases 3-5mm space compared with design size can be reserved, to meet the requirement of increasing deep-cavity thin-wall reinforcement 2 face size.Concrete modification operation is for first to make electrode special, and electrode size can refer to the height of the deep-cavity thin-wall reinforcement 2 raised in Fig. 2; Then use electric discharge machining apparatus to beat mould carries out electricity for the position of die casting deep-cavity thin-wall reinforcement 2 end face, progressively carry out until this position reaches the requirement of increasing face size; The electricity at this position played the careful reconditioning of vestige by pincers worker personnel more smooth, remainder without the need to changing, and then completes whole work of mould amendment.

Secondly, utilize amended die casting CVT case of transmission 1, deep-cavity thin-wall reinforcement 2 end face of gained comparatively design size is raised to some extent, as shown in Figure 2.Whole product design is not any change, only that the end face of deep-cavity thin-wall reinforcement 2 has raised 3-5mm, the cold shut defects of this end still can produce, and just the position of this cold shut defects also to move up 3-5mm with end face, and then makes cold shut deeply and can not arrive the due design attitude of end face.

Finally, by follow-up milling cast gate operation, part (the cold shut defects also hereinto) milling that easily deep-cavity thin-wall reinforcement 2 end face can be exceeded design size 3-5mm removes, make deep-cavity thin-wall reinforcement 2 end face cold shut defects to final products without any quality influence, products obtained therefrom contrast uses the certified products of the Mould Machining before amendment without any difference.

When Die Casting Workshop is implemented, match die casting machine and amended mould of use re-starts die casting test, by visual examination and processing checking, learn that process modifications effect is very good, the product rejection problem that circular arc type deep-cavity thin-wall reinforcement 2 end face cold shut defects causes obtains basic solution.In like manner, the applicable said method of the cold shut defects that in CVT stepless gearbox clutch housing, deep-cavity thin-wall reinforcement 2 end face exists solves, and the method even may extend on arbitrary deep-cavity thin-wall type die casting position needing solution cold shut problem.

Claims

1. solve a method for CVT electrodeless variable-speed tank shell deep-cavity thin-wall reinforcement end face cold shut, it is characterized in that, concrete steps are as follows:

For the position of die casting deep-cavity thin-wall reinforcement (2) end face on A, amendment CVT stepless gearbox housing mould, reserve and this end face can be made to increase the space of 3-5mm compared with design size;

B, utilize amended die casting CVT electrodeless variable-speed tank shell, deep-cavity thin-wall reinforcement (2) end face of gained naturally comparatively design size raise to some extent;

C, by milling cast gate operation, the part milling that deep-cavity thin-wall reinforcement (2) end face exceeds design size to be removed.

2. a kind of method solving CVT electrodeless variable-speed tank shell deep-cavity thin-wall reinforcement end face cold shut according to claim 1, it is characterized in that, described CVT electrodeless variable-speed tank shell comprises CVT case of transmission (1) and clutch housing.

3. a kind of method solving CVT electrodeless variable-speed tank shell deep-cavity thin-wall reinforcement end face cold shut according to claim 1 and 2, it is characterized in that, to the retouching operation of mould in described steps A, comprise: first make electrode special, then adopt the dynamo-electric molding tool of spark machined to the size required, then it is smooth to play the thin reconditioning in position to electricity.