Hydraulic booster with noise reducing tubular member disposed in spool
US5105623A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Sep 26, 1990 |
| Grant date | Apr 21, 1992 |
| Priority date | — |
| Expiry date | Sep 26, 2010 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB60T13/143
- WIPO fieldTransport
- WIPO sectorMechanical engineering
Abstract
The invention is directed to a hydraulic booster for use in a hydraulic braking system of an automotive vehicle having a power source for generating a hydraulic power pressure, a reservoir and a master cylinder for generating a hydraulic braking pressure in response to movement of an input rod. The hydraulic booster has a housing defining therein a boost chamber, a power piston received in the boost chamber for transmitting a boost force to the master cylinder, and a pressure control valve which introduces the hydraulic power pressure from the power source and controls it in response to the movement of the input rod. The pressure control valve includes a cylinder defining therein a bore and a spool received in the bore. The spool has an axial hole and at least two radial holes facing each other and communicating with the axial hole. And, a tubular member is disposed in the axial hole of the spool to prevent the interference of the hydraulic power pressures introduced into the axial hole through the radial holes facing each other, whereby an uncomfortable noise caused by the interference is effectively prevented.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.