Method of assembling a pump having a noncircular joint

Abstract

A method of assembling a cover to a housing of a pump includes roll-forming a noncircular lip by rotating a roll-forming tool about a longitudinal axis. The roll-forming tool includes first and second rollers engaging the noncircular lip. The method includes applying a load to the noncircular lip, the load being applied parallel to a longitudinal axis, and continuing rotating the roll-forming tool about the longitudinal axis. The longitudinal axis remains in a fixed position. Rotating the roll-forming tool causes the first and second rollers to concurrently operably engage the noncircular lip, deform the noncircular lip, and assemble the cover to the housing.

What is claimed is: 
     
         1 . A method of assembling a cover to a housing of a pump, the method comprising:
 disposing a noncircular plate within a cavity at least partially defined by a noncircular lip;   rotating a roll-forming tool about a longitudinal axis, the roll-forming tool including a central shaft having the longitudinal axis, a first axle having a first lateral axis that extends substantially perpendicular to the longitudinal axis, a second axle having a second lateral axis that extends substantially perpendicular to the longitudinal axis, a first roller rotatably coupled to the first axle and adapted to rotate about the first lateral axis, and a second roller rotatably coupled to the second axle and adapted to rotate about the second lateral axis, the first roller and the second roller being radially positioned with respect to the longitudinal axis and circumferentially spaced with respect to each other;   while rotating the roll-forming tool, engaging the first and second rollers with the noncircular lip,   applying a load to the noncircular lip, the load being applied parallel to the longitudinal axis; and   continuing rotating the roll-forming tool about the longitudinal axis, the longitudinal axis remaining in a fixed position, wherein rotating the roll-forming tool causes the first and second rollers to concurrently operably engage the noncircular lip, deform the noncircular lip, and assemble the cover to the housing.   
     
     
         2 . The method of  claim 1 , wherein the noncircular lip engages the noncircular plate in a deformed configuration. 
     
     
         3 . The method of  claim 1 , further comprising disposing a seal within the cavity prior to disposing the noncircular plate within the cavity, wherein the noncircular plate engages the seal when the noncircular lip is in a deformed configuration. 
     
     
         4 . The method of  claim 3 , wherein the seal comprises at least one of: room-temperature-vulcanizing (RTV) silicone, an O-ring, a seal-in-place gasket, and a noncircular-cross-section seal. 
     
     
         5 . The method of  claim 3 , wherein when the noncircular lip is in the deformed configuration, the noncircular plate encloses and hermetically seals a cavity of the pump. 
     
     
         6 . The method of  claim 1 , wherein
 the noncircular lip at least partially defines an undeformed shape prior to the engaging the first and second rollers;   in the undeformed shape, the noncircular lip includes an outer surface, an inner surface, and a top surface extending between the outer surface and the inner surface, the inner surface being closer to the longitudinal axis than the outer surface; and   the top surface extends substantially perpendicular to the longitudinal axis and is adapted to engage the first and second rollers.   
     
     
         7 . The method of  claim 6 , wherein:
 the outer surface forms a first angle with the top surface, the first angle being greater than 0° and less than or equal to about 90°; and   the inner surface forms a second angle with the top surface, the second angle being greater than 0° and less than or equal to about 90°, the second angle being greater than the first angle.   
     
     
         8 . The method of  claim 1 , further comprising maintaining a constant spacing between the first roller and the second roller during a complete revolution of the roll-forming tool, wherein the first axle, the second axle, the first roller and the second roller rotate together with the central shaft.