Bellows pneumatic system
US4882978A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 20, 1989 |
| Grant date | Nov 28, 1989 |
| Priority date | — |
| Expiry date | Mar 20, 2009 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF04B33/00
- WIPO fieldEngines, pumps, turbines
- WIPO sectorMechanical engineering
Abstract
A pneumatic system (10) is shown in its most preferred use in a spray gun (12) to remotely control a pressure washer. The system (10) generally includes an integrally formed, homogenous squeeze box (40) including a location ear (52), a nose tube (46), a bellows (44), and a discharge tube (48). Bellows (44) is generally rectangular in cross section and includes a flat top (62) and bottom (63) and accordion sides (64) having generally longitudinal fold lines (72, 74, 76, 78, 80) which are generally parallel to the mold part line (93) and the tubes (46, 48) but include a 2.degree. draft for ease in mold removal. A valve and spring tube (42) is loosely received on the nose tube (46) for sealing a vent hole (60) provided therein when the bellows (44) is compressed by a trigger (30) of gun (12) and for biasing the trigger (30) to an uncompressed bellows condition. In its most preferred form, the squeeze box (40) is blow molded, with the bellows cavities (44') of the mold halves (92, 94) having a generally trapezoidal cross section defining major longitudinal undercuts (102).
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.