Pump Rod Mounting Linkage for Fast, Aligned Retention

Solution Overview

Problem

Existing axial displacement pumps in fluid dispensing systems require time-consuming and loose-part processes for attachment to drive housings, and experience misalignment of driving forces, leading to wear on components.

Innovation Solution

A pump rod with a load concentrating feature and a driving link system that minimizes misalignment by securing the pump rod within a cavity using a U-shaped flange and a clamping mechanism, ensuring concentric alignment and reducing side loads.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If the pump rod is attached to the reciprocating drive by a pin, then the pump rod can be secured to the drive, but the attachment process becomes time-intensive and requires loose parts and tools

Engineering Contradiction:

Improvesecure attachmentVSAvoidattachment time

Core Design Contradiction:

ReliabilityVSLoss of time

Solution Approach 1:

The pump rod head is merged with the attachment mechanism, integrating the securing function directly into the pump rod structure. The driven portion of the pump rod includes a head with an opening that receives the reciprocating drive, eliminating the need for separate pins and fasteners. This integration allows the pump rod to be secured to the drive by simply inserting it into the drive housing, reducing attachment time and eliminating loose parts.

Inventive Principle:

Principle #5Merging (Combining)

Solution Approach 2:

The pin and fastener components are extracted from the attachment system. Instead of using a pin to connect the pump rod to the reciprocating drive, the design removes these intermediate elements and creates a direct insertion fit where the pump rod head receives the drive mechanism. This extraction simplifies the attachment process and eliminates the need for tools.

Inventive Principle:

Principle #2Taking out (Extraction)

2Reliability

If the pump rod is pinned to the reciprocating drive, then the connection is secure, but the process requires loose parts and several tools

Engineering Contradiction:

Improveconnection securityVSAvoidnumber of parts

Core Design Contradiction:

ReliabilityVSDevice complexity

Solution Approach 1:

The pump rod head is merged with the attachment mechanism, integrating the securing function directly into the pump rod structure. The driven portion of the pump rod includes a head with an opening that receives the reciprocating drive, eliminating the need for separate pins and fasteners. This integration allows the pump rod to be secured to the drive by simply inserting it into the drive housing, reducing attachment time and eliminating loose parts.

Inventive Principle:

Principle #5Merging (Combining)

Solution Approach 2:

The pump rod head serves multiple functions: it provides the structural end of the rod, creates the connection interface with the reciprocating drive, and acts as the securing mechanism itself. The opening in the head receives the drive, and the interference fit or clearance fit design provides both alignment and retention, making the pump rod head a multi-functional component that eliminates the need for separate fastening elements.

Inventive Principle:

Principle #6Universality (Multi-functionality)

3Ease of operation

If the pump rod experiences driving forces not coincident with the centerline, then the pump can operate, but the pump rod experiences wear on various components

Engineering Contradiction:

Improvedriving force applicationVSAvoidcomponent wear

Core Design Contradiction:

Ease of operationVSReliability

Solution Approach 1:

The pump rod head includes a driven portion with an opening that is preliminarily configured to receive the reciprocating drive in a pre-aligned position. The head geometry and opening placement are designed in advance to guide the drive into proper alignment with the pump rod centerline, preventing misalignment before operation begins. This preliminary alignment configuration ensures that driving forces remain coincident with the centerline during operation.

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The pump rod head acts as an intermediary element between the reciprocating drive and the pump rod shaft. The head includes an opening that receives the drive and transfers forces to the shaft through a controlled interface. This intermediary structure ensures that forces from the drive are properly directed along the centerline of the pump rod, preventing side loads and wear on components.

Inventive Principle:

Principle #24Intermediary (Mediator)

Data Source

PatentUS20260002530A1Pump mounting and retention

Publication Date: 2026.01.01 GRACO MINNESTOA INC

AI summary

A displacement pump is configured to mount to a drive housing. A reciprocating drive is connectable to a pump rod of the displacement pump and includes a connecting rod and a drive link that receives a head of the pump rod. A tightening ring connects the displacement pump to the drive housing to mount the displacement pump to the drive housing.