Patent ID: 11938606
Assignee: MONTABERT
Field: Machine tools (Mechanical engineering)
Classification: CPC B  E | IPC B  E

Claim 17:
18. The hydraulic rotary-percussive hammer drill according to claim 1, further comprising:
a front backup sealing gasket which is annular and which extends around the shank, the front backup sealing gasket being located at the front of the front main sealing gasket and being fastened to the fluid injection portion, the front backup sealing gasket being configured to tightly cooperate with a third shank portion of the shank,
an additional leakage passage which is defined between the shank and the fluid injection portion and which extends from the front main sealing gasket up to the front backup sealing gasket, a leakage flow being intended to flow in the additional leakage passage in case of injection fluid leakage at the front main sealing gasket,
at least one additional fluid discharge orifice which is provided on the fluid injection portion and which is fluidly connected to the additional leakage passage, the at least one additional fluid discharge orifice being configured to discharge leakage flow flowing in the additional leakage passage outwardly of the hydraulic rotary-percussive hammer drill,
additional pressure drop generation means disposed in the additional leakage passage and configured to generate pressure drops in the additional leakage passage when a leakage flow flows in the additional leakage passage.