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A fuel injection apparatus for internal combustion engines, having a pump piston, which is guided in a cylinder bore and driven to reciprocate by a cam drive. The pump piston defines a pump work chamber with its face end. The pump work chamber communicates with an injection valve via a pressure cond

A fuel injection apparatus for internal combustion engines, having a pump piston, which is guided in a cylinder bore and driven to reciprocate by a cam drive. The pump piston defines a pump work chamber with its face end. The pump work chamber communicates with an injection valve via a pressure conduit and is supplied with fuel and relieved via a fuel line. The cam drive acts upon the pump piston via a rocker bolt, a tappet bolt, and a tappet insert, and the connections from the tappet bolt to both the rocker bolt and the tappet insert are embodied in the manner of ball joints. For simple installation of the tappet bolt, it is axially secured in relation to the rocker and to a tappet sleeve, which receives the tappet insert, via securing elements having elastic stretching properties, which expand to the size of the outer diameter of the ball head when a certain force is exerted, so that the tappet bolt can be installed and removed without disassembling the whole pump.

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1. A fuel injection device for internal combustion engines, having a pump piston (1) guided in a cylinder bore (3) disposed in a pump housing (5), a cam drive for driving the pump piston axially back and forth counter to a force of a restoring spring (43), said pump piston having one face end, remot

1. A fuel injection device for internal combustion engines, having a pump piston (1) guided in a cylinder bore (3) disposed in a pump housing (5), a cam drive for driving the pump piston axially back and forth counter to a force of a restoring spring (43), said pump piston having one face end, remote from the cam drive, defining a pump work chamber (7) that communicates with an injection valve (15) via a pressure line (13) and can be filled with fuel via a fuel line (17), a tappet bolt (25) by which the cam drive acts upon the pump piston (1), said tappet bolt (25) includes a spherical tappet end remote from the cam drive which is guided in a ball socket (57) of a tappet insert (27) joined to the pump piston (1), said spherical tappet end remote from the cam drive forms a ball head end (55) with a partially spherical face remote from the tappet insert (27) and ending at a shaft of the tappet bolt (25), and the tappet bolt (25) is axially secured in place by a first securing element (59) between the partially spherical face on the head end (55) of the tappet bolt (25) remote from the tappet insert (27) and a tappet sleeve (35), and said first securing element (59) is embodied as an elastic securing element, which at least enables a fixed axial motion of the tappet bolt (25) in the tappet sleeve (35) and said first elastic securing element (59) is locked in detent fashion in a recess (61) of the tappet sleeve. 2. A fuel injection device according to claim 1, in which the tappet bolt (25), on its end remote from the pump piston (1), is connected in a ball-and-socket joint to a transfer member (67) driven by the cam drive. 3. A fuel injection device according to claim 2, in which the ball-and-socket joint comprises a ball socket (63) and a ball head (65), which is engaged from behind by a second elastic securing element (59') held in the ball socket (63). 4. A fuel injection device according to claim 1, in which the first elastic securing element (59) is embodied as an O-ring, which is guided with enough play in said recess (61) which is configured as an annular groove of semicircular cross section, in which said annular groove is deep enough to allow the first elastic securing element to expand, that with an inner diameter the first elastic securing element can widen to a size of an outer diameter of the ball head (55). 5. A fuel injection device according to claim 3, in which the first elastic securing element (59) is embodied as an O-ring, which is guided with enough play in said recess (61) which is configured as an annular groove of semicircular cross section, in which said annular groove is deep enough to allow the first elastic securing element to expand, that with an inner diameter the first elastic securing element can widen to a size of an outer diameter of the ball head (55). 6. A fuel injection device according to claim 1, in which the first elastic securing element (59) is embodied as an O-ring, which is guided with enough play in said recess (61) which is configured as an annular groove of rectangular cross section, in which said annular groove is deep enough to allow the first elastic securing element to expand, that with an inner diameter the first elastic securing element can widen to a size of an outer diameter of the ball head (55). 7. A fuel injection device according to claim 3, in which the first elastic securing element (59) is embodied as an O-ring, which is guided with enough play in said recess (61) which is configured as an annular groove of rectangular cross section, in which said annular groove is deep enough to allow the first elastic securing element to expand, that with an inner diameter the first elastic securing element can widen to a size of an outer diameter of the ball head (55). 8. A fuel injection device according to claim 1, in which the first elastic securing element (59) is embodied as a circular snap ring, which is guided in an annular groove, in which the annular groove is sized so that the annular groove enables a diameter expansion of the inserted snap ring that is required in order to allow the installation of the particular ball head (55). 9. A fuel injection device according to claim 3, in which the first elastic securing element (59) is embodied a circular snap ring, which is guided in an annular groove, in which the annular groove is sized so that the annular groove enables a diameter expansion of the inserted snap ring that is required in order to allow the installation of the particular ball head (55). 10. A fuel injection device according to claim 1, in which the first elastic securing element (59) takes the form of an open wire lock washer that is bent into a five-sided, closed polygonal shape, whose outer diameter D1 is equal to a base diameter of the recess (61) and whose inner diameter D2 is smaller than the outer diameter of the ball head (55). 11. A fuel injection device according to claim 3, in which the first elastic securing element (59) takes the form of an open wire lock washer that is bent into a five-sided, closed polygonal shape, whose outer diameter D1 is equal to a base diameter of the recess (61) and whose inner diameter D2 is smaller than the outer diameter of the ball head (55). 12. A fuel injection device according to claim 10, in which a defined increased spacing (b) is provided between the ends of the wire lock washer, by shortening one of the sides. 13. A fuel injection device according to claim 1, in which the first elastic securing element (59) takes the form of an open wire lock washer that is bent into a four-sided, closed polygonal shape, whose transitions between the sides of the polygon are embodied in a circular shape. 14. A fuel injection device according to claim 3, in which the first elastic securing element (59) takes the form of an open wire lock washer that is bent into a four-sided, closed polygonal shape, whose transitions between the sides of the polygon are embodied in a circular shape. 15. A fuel injection device according to claim 1, in which the first elastic securing element (59) takes the form of an open wire lock washer that is bent into a three-sided, closed polygonal shape, whose transitions between the sides of the polygon are embodied in a circular shape. 16. A fuel injection device according to claim 3, in which the first elastic securing element (59) takes the form of an open wire lock washer that is bent into a three-sided, closed polygonal shape, whose transitions between the sides of the polygon are embodied in a circular shape. 17. A fuel injection device according to claim 8, in which the snap ring is formed as a wire having a circular cross section. 18. A fuel injection device according to claim 10, in which the snap ring is formed as a wire having a circular cross section. 19. A fuel injection device according to claim 3, in which the second elastic securing element is a profiled sheet metal part (81) embodied as a ring sleeve, which is locked in detent fashion to a circumferential wall of a part of the tappet bolt (25) forming the ball socket (63) via detent elements (73), and which has spring components (83) that protrude into a region where the ball head (65) enters the socket (63). 20. A fuel injection device according to claim 2, in which a transfer of a motion from the cam drive to the tappet bolt (25) is effected by means of a rocker (11), and a rocker bolt (67) serves as a transfer member which is screwed into an end of the rocker oriented toward the tappet bolt (25), and an end of the rocker bolt (67) that acts upon the tappet bolt (25) is embodied as a ball head (65), which engages the end of the tappet bolt (25) that is embodied as a ball socket (63), that forms the aforementioned ball-and-socket joint.