Fluid injection device, and mechanical system equipped with such a device

A device for injecting a fluid into a mechanical system that may undergo heating, the device comprising:

• a body containing a thermally triggered charge generating combustion gas, ignition of the charge being able to be triggered under the action of an ignition command and/or under the effect of a heat contribution, from a heating area of the body toward the charge,
• a reservoir containing the fluid,
• a fastener fastening the device to the mechanical system, the fastener adapted to put the reservoir in fluid communication with the mechanical system, and
• a delivery device delivering pressurized fluid outside the reservoir using combustion gases,
• wherein the fastener comprise at least one injection sleeve provided with an outer thread coated with an adhesive anti-loosening coating,
• wherein the injection sleeve is formed from a material having a 0.2% deformation yield strength Re0.2 comprised between 500 and 700 MPa, and a tensile strength Rmax comprised between 700 and 900 MPa,
• wherein the delivery device delivering the pressurized fluid outside the reservoir comprises a non-fragmentable membrane, which initially covers the reservoir and breaks when the pressure of the fluid in the reservoir exceeds a predetermined pressure threshold,
• wherein the membrane is located in a volume delimited by the outer thread of the injection sleeve,
• wherein the flow rate of the pressurized fluid outside the reservoir is regulated, with at least one of:
• a periodic delivery of fluid over a reduced time interval, shorter than five seconds;
• a regular and continuous delivery of fluid over a period of several minutes;
• or
• an intermittent delivery of fluid, through successive injections, over several minutes,
• and wherein the device includes a miniaturized unit for signaling triggering of the charge, the miniaturized unit comprising a temperature sensor and/or a pressure sensor arranged in a housing of the charge, so that a combustion of the charge can be detected from outside the device.