Power driven hammer drill
US5320177A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 26, 1993 |
| Grant date | Jun 14, 1994 |
| Priority date | — |
| Expiry date | Mar 26, 2013 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB25D2250/335
- WIPO fieldMachine tools
- WIPO sectorMechanical engineering
Abstract
The invention provides an improved intermediate housing incorporated in a power driven hammer drill, which is light in weight, easily and safely handled, and uncostly manufactured. The intermediate housing of the invention includes a bearing member and a cylindrical piston housing member which are integrally composed of a synthetic resin having high tenacity and excellent heat resistance and wear resistance. The intermediate housing further includes a plurality of ribs radially extending from the piston housing member to give a sufficient strength durable to a stress applied onto the piston housing member. In the intermediate housing thus constructed, the bearing member has at least one opening for feeding an air flow generated by a fan while the piston housing member includes at least one air conduit for circulating the air flow. This structure efficiently prevents overheat and thermal deformation of the piston housing member and the bearing member in continuous operation of the hammer drill.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.