WE CLAIM:
1. An electromagnetic fuel injection valve comprising a valve housing (2) including,
at a front portion, a valve seat member (3) having a conical valve seat (8) and a valve hole
5 (7) penetrating a central portion of the valve seat (8); a nozzle plate (10) bonded to an end
portion of the valve seat (8) and having a plurality of fuel injection holes (17a, 17b); a valve
body (13) having, at a front end portion, a spherical valve portion (14) for opening and
closing the valve hole (7) in cooperation with the valve seat (8); and an electromagnetic
operation device (11) that provides an opening operation to the valve body (13) when power
10 is supplied, in which the valve seat member (3) is provided with fuel passages (37) and a
valve guide hole (9) having a guide surface portion (9a) that guides opening and closing
operations of the valve body (13), and an annular fuel collection chamber (49) is provided
between the valve seat (8) and the valve hole (7), a flat fuel diffusion chamber (50) to which
an outlet of the valve hole (7) is open is provided between the valve seat member (3) and
15 the nozzle plate (10) bonded to a front end surface of the valve seat member (3), the fuel
diffusion chamber (50) having a greater diameter than the valve hole (7), and the plurality
of fuel injection holes (17a, 17b) that is open to the fuel diffusion chamber (50) is disposed
in the nozzle plate (10) by being separated from the valve hole (7) in a radial direction,
wherein
20 the fuel passages (37) are defined in plural in the valve guide hole (9) to surround
the spherical valve portion (14) and to be connected to the valve seat (8), and
the number of the fuel injection holes (17a, 17b) is greater than the number of the
fuel passages (37) and the plurality of fuel injection holes (17a, 17b) not in phase with the
fuel passages (37) is included in plural.
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2. The electromagnetic fuel injection valve according to claim 1, wherein
the valve guide hole (9) is configured to be forged and molded to have a polygonal
cross-section having 4 to 6 guide surface portions (9a) and 4 to 6 inner corner portions (9b),
and
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the fuel passages are defined by the guide surface portions (9a) and the inner
corner portions (9b).
3. The electromagnetic fuel injection valve according to claim 1 or 2, wherein
5 the plurality of fuel injection holes (17a, 17b) is disposed on an imaginary circle
(C) having the axis line (Y) of the valve hole as a center, the plurality of fuel injection holes
(17a, 17b) is grouped into a first fuel injection hole group (17A) consisting of the plurality
of fuel injection holes (17a, 17b) disposed on one semicircle (Ca) of the imaginary circle
(C) divided by a bisecting line (L) and a second fuel injection hole group (17B) consisting
10 of the plurality of fuel injection holes (17a, 17b) disposed on the other semicircle (Cb) of
the imaginary circle (C), hole axis lines (Aa, Ab) of the respective fuel injection holes (17a,
17b) are inclined to be separated from the axis line (Y) of the valve hole toward the
downstream side, in each of the fuel injection hole groups (17A, 17B), an outer fuel
injection hole (17b) farther from a group center (O) than a central fuel injection hole (17a)
15 close to the group center (O) is formed to have a small diameter, and a deflection angle (β)
of the outer fuel injection hole (17b) with respect to the bisecting line (L) is set to be greater
than a pitch angle (α) between the fuel injection holes (17a, 17b).