Pump valve retainer

In combination with a pump which comprises a fluid bore and a valve member which is positioned in the fluid bore, the fluid bore comprising a central axis and a pair of generally diametrically opposed, radially inwardly extending protrusions, the improvement comprising a retainer for the valve member which includes:

• an elongated retainer head;
• and
• a retainer hub which is connected to or formed integrally with the retainer head and which includes a cylindrical bore within which a stem portion of the valve member is slidably received;
• the retainer head comprising a length in a plane perpendicular to the central axis which is greater than the distance between the protrusions and an overall width in the plane perpendicular to the central axis which is less than the distance between the protrusions, such that in a first angular orientation the entire retainer head can be inserted into the fluid bore past the protrusions and in a second angular orientation the retainer head is prevented from being inserted into the fluid bore past the protrusions;
• the retainer head further comprising a pair of generally diametrically opposed peripheral grooves which are each defined by a corresponding pair of upper and lower peripheral lips and within which the protrusions are received when the retainer is rotated from its first angular orientation to its second angular orientation;
• wherein when the protrusions are received within the grooves the retainer is secured to the pump and the valve member is thereby movably secured within the fluid bore.

In combination with a pump which comprises a fluid bore and a valve member which is positioned in the fluid bore, the fluid bore comprising a central axis and a pair of generally diametrically opposed, radially inwardly extending protrusions which are spaced apart a distance, the improvement comprising a retainer for the valve member which includes:

• a retainer head which comprises a pair of diametrically opposed grooves within which the protrusions are received to thereby secure the retainer head within the fluid bore;
• a retainer hub which is connected to or formed integrally with the retainer head and which is movably coupled to the valve member;
• each groove defining a corresponding pair of upper and lower lips, the upper lips being disposed in a first plane which is generally perpendicular to the central axis and the lower lips being disposed in a second plane which is generally perpendicular to the central axis;
• wherein the retainer head comprises a first width in a direction perpendicular to a line joining the upper lips and a second width in a direction perpendicular to a line joining the lower lips;
• and
• wherein each of the first and second widths is less than the distance between the protrusions.