Device for adjusting the timing in fuel injection pumps

Claim 2

In a device for adjusting the timing of a fuel injection pump associated with an internal combustion engine, said device being of the known type that includes (A) a movable adjusting member to effect a change in said timing, (B) conduit means carrying hydraulic fluid under pressure to said adjusting member for causing displacement thereof in one direction, (C) means exerting a force to said adjusting member in a second, opposite direction, (D) a check valve contained in said conduit means and including a movable valve member openable towards said adjusting member, (E) bypass channel means communicating with said conduit means downstream of said check valve and upstream of said adjusting member, and (F) a discharge valve including a movable valve member opening and closing said bypass channel means, the improvement comprising, A. an electromagnet operatively connected with the movable valve member of said discharge valve to cause opening or closing of said bypass channel and B. means operatively connecting said electromagnet with the movable valve member of said check valve to cause closing thereof upon opening of said discharge valve.

Claim 3

In a device for adjusting the timing of a fuel injection pump associated with an internal combustion engine, said device being of the known type that includes (A) a movable adjusting member to effect a change in said timing, (B) conduit means carrying hydraulic fluid under pressure to said adjusting member for causing displacement thereof in one direction, (C) means exerting a force to said adjusting member in a second, opposite direction, (D) a check valve contained in said conduit means and including a movable valve member openable towards said adjusting member, (E) bypass channel means communicating with said conduit means downstream of said check valve and upstream of said adjusting member, and (F) a discharge valve including a movable valve member opening and closing said bypass channel means, the improvement comprising, an electromagnet operatively connected with the movable valve member of said discharge valve to cause opening or closing of said bypass channel, said electromagnet including a reciprocable armature being movable in a first direction by the fluid pressure prevailing in said conduit means upstream of said check valve, said armature being movable in a second, opposite direction upon energization of said electromagnet, said armature being operatively connected with the movable valve member of said discharge valve to open the same when said armature is moved in said first direction upon de-energization of said electromagnet.

Claim 4

In a device for adjusting the timing of a fuel injection pump associated with an internal combustion engine, said device being of the known type that includes (A) a movable adjusting member to effect a change in said timing, (B) conduit means carrying hydraulic fluid under pressure to said adjusting member for causing displacement thereof in one direction, (C) means exerting a force to said adjusting member in a second, opposite direction, (D) a check valve contained in said conduit means and including a movable valve member openable towards said adjusting member, (E) bypass channel means communicating with said conduit means downstream of said check valve and upstream of said adjusting member, and (F) a discharge valve including a movable valve member opening and closing said bypass channel means, the improvement comprising, an electromagnet operatively connected with the movable valve member of said discharge valve to cause opening or closing of said bypass channel, said electromagnet including a reciprocable armature being movable in a first direction by the fluid pressure prevailing in said conduit means upstream of said check valve, said armature being movable in a second, opposite direction upon energization of said electromagnet, said armature being operatively connected with the movable valve member of said discharge valve to open the same when said armature is moved in said first direction upon de-energization of said electromagnet.

Claim 5

In a device for adjusting the timing of a fuel injection pump associated with an internal combustion Engine, said device being of the known type that includes (A) a movable adjusting member to effect a change in said timing, (B) conduit means carrying hydraulic fluid under pressure to said adjusting member for causing displacement thereof in one direction, (C) means exerting a force to said adjusting member in a second, opposite direction, (D) a check valve contained in said conduit means and including a movable valve member openable towards said adjusting member, (E) bypass channel means communicating with said conduit means downstream of said check valve and upstream of said adjusting member, and (F) a discharge valve including a movable valve member opening and closing said bypass channel means, the improvement comprising, A. an electromagnet operatively connected with the movable valve member of said discharge valve to cause opening or closing of said bypass channel and B. an electronic regulating device emitting command signals to said electromagnet for matching the actual position of said adjusting member with the ideal position thereof, said actual position depends upon at least one variable characterizing the operation of said internal combustion engine.

Claim 6

In a device for adjusting the timing of a fuel injection pump associated with an internal combustion Engine, said device being of the known type that includes (A) a movable adjusting member to effect a change in said timing, (B) conduit means carrying hydraulic fluid under pressure to said adjusting member for causing displacement thereof in one direction, (C) means exerting a force to said adjusting member in a second, opposite direction, (D) a check valve contained in said conduit means and including a movable valve member openable towards said adjusting member, (E) bypass channel means communicating with said conduit means downstream of said check valve and upstream of said adjusting member, and (F) a discharge valve including a movable valve member opening and closing said bypass channel means, the improvement comprising, A. an electromagnet operatively connected with the movable valve member of said discharge valve to cause opening or closing of said bypass channel and B. an electronic regulating device emitting command signals to said electromagnet for matching the actual position of said adjusting member with the ideal position thereof, said actual position depends upon at least one variable characterizing the operation of said internal combustion engine.

Claim 7

An improvement as defined in claim 1, including A. a chamber in continuous hydraulic communication with said adjusting member, B. a first opening provided in said chamber for establishing communication between said chamber and a source supplying said hydraulic fluid under pressure, C. a first valve seat defining said first opening, D. a first sphere disposed in said chamber and associated with said first valve seat, said first sphere constitutes the movable member of said check valve, E. a second opening provided in said chamber for establishing communication between said chamber and said bypass channel means, F. a second valve seat defining said second opening, and G. a second sphere disposed in said chamber and associated with said second valve seat, said second sphere constitutes the movable member of said discharge valve.

Claim 8

An improvement as defined in claim 4, wherein said spheres are cooperating in such a manner that, when said electromagnet exerts no opening force on said second sphere, said hydraulic fluid pressure unseats said first sphere whereby the latter displaces said second sphere pressing it into engagement with said second valve seat, and when said electromagnet exerts an opening force on said second sphere, the latter is unseated, thereby displacing said first sphere and pressing it into engagement with said first valve seat.

Claim 9

An improvement as defined in claim 5, wherein the fluid pressure in said chamber, when greater than the opening force exerted on said first sphere and greater than the opening force exerted on said second sphere, presses both spheres into their respective associated valve seats.