Pump transmission carriage assembly

A metering pump comprising:

• a motor having a motor shaft extending through a drive housing;
• a carriage assembly having a first end and a second end, the carriage assembly disposed around the motor shaft and within the drive housing such that the first end of the carriage assembly is spaced from and not directly supported by the drive housing, wherein the carriage assembly has an inner ridge;
• a plunger return block mounted to the first end of the carriage assembly;
• a piston disposed along an axis and mounted to the second end of the carriage assembly to provide a first contact point for maintaining the alignment of the carriage assembly with the axis of the piston;
• a carriage bearing disposed on the motor shaft and within the carriage assembly, slidably coupled to the carriage assembly, and configured to reduce friction for reciprocating and linear translation of the carriage assembly, wherein the carriage bearing has a groove in an outer surface;
• a cam coupled to the motor shaft to rotate with the motor shaft;
• and
• a bearing disposed around the cam to rotate therewith and to contact the piston and the plunger return block;
• wherein the carriage assembly inner ridge is positioned within the carriage bearing groove to slidably couple the carriage assembly inner ridge to the carriage bearing groove to allow the carriage assembly inner ridge to translate along the carriage bearing groove and to provide a second contact point for maintaining alignment of the carriage assembly with the axis of the piston.

A metering pump comprising:

• a motor having a motor shaft extending through a drive housing;
• a carriage assembly having a first end and a second end, the carriage assembly disposed around the motor shaft and within the drive housing such that the first end of the carriage assembly is fully contained within the drive housing, wherein the carriage assembly has an inner ridge;
• a plunger return block mounted to the first end of the carriage assembly;
• a piston disposed along an axis and mounted to the second end of the carriage assembly;
• a first contact structure configured to provide a first contact point for maintaining the alignment of the carriage assembly with the axis of the piston;
• a second contact structure aligned with the motor shaft wherein the second contact structure is a carriage bearing having a grooved outer surface and configured to reduce friction for reciprocating and linear translation of the carriage assembly;
• a cam coupled to the motor shaft to rotate with the motor shaft;
• and
• a bearing disposed around the cam to rotate therewith and to contact the piston and the plunger return block;
• wherein the carriage assembly inner ridge is positioned within the carriage bearing grooved outer surface to slidably couple the carriage assembly inner ridge to the carriage bearing grooved outer surface to allow the carriage assembly inner ridge to translate along the carriage bearing grooved outer surface and to provide a second contact point for maintaining alignment of the carriage assembly with the axis of the piston.