Cooling sprayer with valve

1. A piston cooling sprayer for internal combustion engines, including a sprayer body with an axial passage through it in which are accommodated a tubular guide liner with an axial passage through it and a valve that cooperates with a main seat and a return spring, the sprayer body having an upstream section conformed to be connected to an engine cooling fluid feed passage, an intermediate section with at least one radial outlet passage and one fluid outlet tube, and a downstream retaining section, the tubular guide liner being fixed coaxially in the axial through-passage and having an upstream section leaving a peripheral space for the axial passage of fluid between its external surface and the internal surface of the axial through-passage and between the main seat and the radial outlet passage, the valve sliding axially in the axial passage through the tubular guide liner toward and away from the main seat and being urged axially toward the main seat by the return spring accommodated in the axial passage through the tubular guide liner,

wherein:

the main seat is formed in the mass of the sprayer body by a shoulder in the axial through-passage,

the tubular guide liner comprises a downstream liner section fixed in the downstream retaining section of the sprayer body beyond the radial outlet passage,

the upstream section of the tubular guide liner terminates in an upstream end that is axially set back from the main seat, in the downstream direction, to define an annular fluid passage between the main seat and the peripheral space.

2. The sprayer according to claim 1 , wherein the downstream section of the tubular guide liner comprises an annular end flange crimped in a downstream section with a shoulder of the axial through-passage, in the downstream retaining section of the sprayer body.

3. The sprayer according to claim 2 , wherein the annular end flange is retained in the downstream section with a shoulder of the axial through-passage by bending an end skirt of the sprayer body over the downstream end face of the annular end flange.

4. The sprayer according to claim 2 , wherein the upstream section of the tubular guide liner is centred coaxially in the axial through-passage of the sprayer body by radial excrescences bearing on the wall of the axial through-passage.

5. The sprayer according to claim 4 , wherein the downstream retaining section of the sprayer body has a length just sufficient for accommodating and crimping the annular end flange of the tubular guide liner beyond the radial outlet passage.

6. The sprayer according to claim 2 , wherein the downstream section of the tubular guide liner comprises a centring section engaged in a corresponding bore of the axial through-passage, in the downstream retaining section of the sprayer body.

7. The sprayer according to claim 1 , wherein the tubular guide liner comprises, in its axial through-passage, a downstream constricting shoulder against which is engaged a return coil spring urging the valve toward the main seat and continued by a vent.

8. The sprayer according to claim 1 , wherein the tubular guide liner comprises, from its upstream end, a guiding bore in which the valve slides with a small functional clearance and that is limited by a shoulder forming a rear seat against which the valve bears in sealed fashion when it is pushed back by the fluid under pressure.

9. The sprayer according to claim 8 , wherein the rear seat is disposed so that, when the valve is bearing on the rear seat, it frees a just sufficient section of the annular fluid passage for the required flow of the cooling fluid.

10. The sprayer according to claim 1 , wherein the valve is a piston or a ball.