US 6,497,030 B1Granted

Method of manufacturing a lead screw and sleeve mechanism using a hydroforming process

AssigneeDana Corporation

InventorRichard A. Marando

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Abstract

A method of manufacturing a sleeve mechanism without the use of machines by using a hydroforming process. The method includes the steps of providing an inner sleeve, an intermediate sleeve, and an outer sleeve concentrically within one another. The concentric sleeves are then expanded by using a hydroforming process such that an external thread is formed on the inner sleeve and an internal thread is formed on the outer sleeve. After the hydroforming process, the intermediate sleeve is removed by using any desired manner, such as melting or chemical dissolution. The relatively small space remaining between the inner and outer sleeves allow them to freely rotate about each other to ensure smooth operation of the screw and sleeve mechanism. Alternatively, the inner and outer sleeves may be hydroformed in separate operations.

Claims6

Dependent claims

A method for manufacturing a lead screw and sleeve mechanism including first and second members that rotate relative to one another such that relative rotational movement causes relative axial movement, said method comprising the steps of:

(a) disposing an inner member, an intermediate member, and an outer member within one another;
(b) disposing the members within a die cavity including an inner surface having a helical thread recess formed therein;
(c) expanding the members into conformance with the die cavity such that an external helical thread is formed on the inner member and an internal helical thread is formed on the outer member;
and
(d) removing the intermediate member from between the inner and outer members to provide a space therebetween that allows the inner and outer members to rotate relative to one another such that relative rotational movement causes relative axial movement.

2 more elements

Dependencies are inferred from the claim text.

Facts

Application: 09/650,955Filed 29 Aug 2000 · us provisional application
Priority: 31 Aug 1999
Granted: 24 Dec 2002
Term ends: Not estimatedThe source records don’t support an estimate.

Classification11 codes

B21D 15/10
Transversely, e.g. helically: by applying fluid pressure
B21D 26/051
Deforming tubular bodies: deforming double-walled bodies
B21D 53/24
Making other particular articles: nuts or like thread-engaging members
F16H 25/24
Screw mechanisms: elements essential to such mechanisms, e.g. screws, nuts