Injector for injecting a fluid, having a tapering inflow area of a through-opening

• US 11,560,868 B2
• Filed: 06/14/2017
• Issued: 01/24/2023
• Est. Priority Date: 06/29/2016
• Status: Active Grant

• Current Assignee: Robert Bosch GmbH
• Original Assignee: Robert Bosch GmbH
• Inventors: Schmieder, Dietmar, Rogler, Philipp
• Primary Examiner(s): Lieuwen, Cody J
• Application Number:
  US16/308,666
• Publication Number:
  US 20190309720A1
• Time in Patent Office: 2,050 Days
• CPC Class Codes: F02M 61/10 Other injectors with elongated valve bodies, i.e. of needle-valve type
• CPC Class Codes: F02M 61/18 Injection nozzles, e.g. having valve seats; Details of valve member seated ends, not otherwise provided for
• CPC Class Codes: F02M 61/1806 characterised by the arrangement of discharge orifices, e.g. orientation or size
• CPC Class Codes: F02M 61/1833 Discharge orifices having changing cross sections, e.g. being divergent

Abstract

An injector for injecting a fluid, including a valve seat, on which a sealing area is situated, and a closing element, which is situated on an injector center line and which, on the valve seat, releases and closes at least one through-opening, the at least one through-opening having a main axis at an angle of inclination with respect to the injector center line, the at least one through-opening having an inflow area, and the inflow area having a tapering design.

Claims

1. An injector for injecting a fluid, comprising:

a valve housing;

a valve seat on which a sealing area is situated, wherein the valve seat is fixed on the valve housing;

a closing element, situated on an injector center line, to release and close a plurality of through-openings at the valve seat, each of the plurality of the through-openings including a main axis at an angle of inclination with respect to the injector center line, the through-openings including an inflow area, and the inflow area having a tapered configuration; and

a return element to hold the closing element in a closed position;

wherein the closing element includes a valve needle, which is linearly movable in an axial direction of the injector along the injector center line,

wherein the closing element is actuated with an actuator,

wherein there is a seal seat in the valve seat, at an injection-side end, configured as a valve ball, of the closing element, includes a fluid reservoir area that is recessed flat in the seal seat,

wherein each of two through-openings are inclined with respect to the injector center line of the injector with the respective angle of inclination,

wherein the fluid reservoir area is recessed in the seal seat in the form of a convex depression, resulting in a fluid reservoir length corresponding to a depression depth along one of the main axes of the plurality of the through-openings,

wherein perpendicular to one of the main axes, a first section plane of the fluid reservoir area is in the seal seat, in which a fluid reservoir flow cross section is present,

wherein at its circumference, the fluid reservoir flow cross section marks a fluid reservoir circumferential contour in the first section plane,

wherein each of the through-openings is subdivided into three flow areas, wherein the three flow areas include the inflow area having an entrance flow cross section in a flow direction downstream from the fluid reservoir area, and wherein each of the through-openings in a flow direction downstream from an intermediate flow area includes an exit flow area having an exit flow cross section, wherein an intermediate flow cross section is less than the exit flow area,

wherein each of the through-openings, in a flow direction downstream from the inflow area, includes the intermediate flow area having the intermediate flow cross section, and downstream from the intermediate flow area includes the exit flow area having the exit flow cross section, the intermediate flow cross section being a narrowest flow cross section of the through-opening,

wherein an inflow length results for the inflow area, an intermediate length results for the intermediate flow area, and an exit length results for the exit flow area, so that as a result, the intermediate flow area along the entire intermediate length, and the exit flow area along the entire exit length, are symmetrical cylindrical shapes with respect to corresponding ones of the main axes,

wherein a narrowest flow cross section of the through-opening is situated in the intermediate flow area and is determined by the intermediate flow cross section,

wherein at least one inner body edge of the through-opening, is situated in the inflow area and/or the fluid reservoir area, so that at least one circumferential contour is provided with a radius and a chamfer, and

wherein the entrance flow cross section of the inflow area is in a second section plane through the valve seat, wherein the second section plane is offset downstream in parallel from the first section plane, which is spanned perpendicularly to a corresponding one of the main axes.

2. The injector as recited in claim 1, wherein the entrance flow cross-section of the inflow area situated transversely to the main axis continuously decreases in a flow direction.

3. The injector as recited in claim 1, wherein the inflow area is configured as an inner hollow cone having a taper angle of an inner wall with respect to a cone center line.

4. The injector as recited in claim 3, wherein the cone center line intersects the main axis of the through-opening at a tilt angle.

5. The injector as recited in claim 1, wherein the entrance flow cross section of the inflow area defining the second section plane includes a non-circular entrance circumferential contour in the second section plane.

6. The injector as recited in claim 5, wherein the entrance circumferential contour has an oval configuration in the second section plane.

7. The injector as recited in claim 6, wherein the entrance circumferential contour, in the second section plane, includes a first circumferential point closest to the main axis of the through-opening, which defines an inscribed angle equal to zero in the second section plane about the main axis, and a second circumferential point situated the farthest away from the main axis of the through-opening, which is situated at an inscribed angle equal to 180°

, and a taper angle is configured to be variable with the inscribed angle.

8. The injector as recited in claim 1, wherein the intermediate flow area and/or the exit flow area is configured to be cylindrical with respect to the main axis.

9. The injector as recited in claim 1, wherein the inflow length and the intermediate length being about equal in size with respect to one another and/or the exit length being greater than the inflow length and/or the intermediate length approximately by a factor of 1.3 to 2.3.

10. The injector as recited in claim 9, wherein the factor is 1.4 to 1.7.