Variable displacement pump or motor and neutral centering mechanism therefor
US4934252A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Mar 9, 1989 |
| Grant date | Jun 19, 1990 |
| Priority date | — |
| Expiry date | Mar 9, 2009 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T74/2063
- WIPO fieldEngines, pumps, turbines
- WIPO sectorMechanical engineering
Abstract
A neutral centering mechanism (15) is disclosed of the type which may be used with a variable pump (11) of the type including a control shaft (33) rotatable about its axis of rotation (35) from a neutral position to first and second operating positions (FIGS. 12 and 13). A control handle (61) is rotatably fixed to the control shaft. The centering mechanism includes a stop plate (41) defining a fixed stop surface (43) and a spring plate (49) which is rotatable about the axis of rotation and defines a movable stop surface (79) in engagement with the handle (61) in the neutral position. The stop plate includes an adjustment screw (45) which adjusts the rotational position of the spring plate to a position in which the movable stop surface is disposed for neutral centering of the control handle and control shaft. A spring (59) biases the handle toward the movable stop surface, when the handle is rotated away from neutral to a first operating position. Another spring (51) biased the spring plate toward the fixed stop surface when the handle and spring plate are rotated, together, away from neutral to a second operating position. As a result, the neutral centering mechanism of the invent…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.