Pump drive cartridge assembly

Abstract

An anti-rotation sleeve for a high-pressure piston compression pump includes a sleeve having a generally cylindrical elongated shape and extending longitudinally along a central axis from a first end to a second end and features that provide orientation and that limit radial movement integrated in an inner diameter of the sleeve. The first end of the sleeve attaches to a base of the pump and the second end slidably engages a lifter body. The lifter body includes corresponding features that provide orientation and that limit radial movement integrated in an outer diameter of the lifter body. By providing an anti-rotation sleeve a relatively simple pump drive cartridge assembly that integrates all pump drive components into a one integral part is enabled. Hence, lower manufacturing and assembly costs, reduced manufacturing and assembly cycle times, and easier packaging conditions are obtained.

Description

TECHNICAL FIELD[0001]The present invention relates to direct injection internal combustion engines; more particularly, to high-pressure mechanical fuel pumps used in high-pressure direct injection fuel systems; and most particularly, to a pump drive cartridge assembly.BACKGROUND OF THE INVENTION[0002]It has become generally known in the art of internal combustion engine design to use high-pressure mechanical fuel pumps in direct injection fuel systems. In known direct injection fuel systems, a high-pressure fuel injection pump typically disposed in the engine compartment close to the injector fuel rail is arranged to supply fuel from a pumping chamber to associated injectors located downstream of the pumping chamber.[0003]Traditionally, high-pressure mechanical fuel pumps require a camshaft follower, such as a flat foot follower or a roller follower, operated by a dedicated camshaft lobe on a rotating jack shaft, to transmit the rotational motion and lift of the camshaft lobe to a l...

AI Technical Summary

Benefits of technology

The present invention provides a cartridge pump drive assembly that integrates all pump drive components in one part. The assembly includes an anti-rotation sleeve that is attached to the high-pressure pump and extends over the plunger and spring assembly, push rod assembly (if required), and lifter body. The anti-rotation sleeve allows the lifter body to slide up and down within it, transmitting the vertical reciprocating motion to the pump. The assembly is designed to minimize weight and friction in the engine. The drive components are all self-contained within the anti-rotation sleeve, making it easy to ship and assemble. The invention provides a simple and cost-effective solution for integrating the pump drive components.

Problems solved by technology

These high fuel pressures generate high loads in the system and require a robust pump and pump drive design.

Based on the design of the internal combustion engine and / or the pump placement, the assembly of the pump and lifter assembly becomes cumbersome and costly, especially when roller followers are used, and alignment of the roller follower and a camshaft is required.

Unless suitably constrained by an anti-rotation guide, a roller follower lifter may rotate axially in its bore during reciprocation, thereby undesirably misaligning its roller follower from the associated camshaft lobe.

Machining of such locating features is cost and labor intensive.

Images