Three-way electromagnetic valve

Claim 2

A three-way electromagnetic valve comprising: a valve body (2) having a supply port (4) through which a pressurized fluid flows, a control port (5), a discharge port (6), a slide bore (3) formed with said ports so as to communicate with the same, and a valve seat (5a) formed between said supply port and said discharge port; a movable member (12) slidably disposed in said slide bore and capable of contacting and moving away from said valve seat, said movable member having an internal passage (17) formed in its body to enable said supply port and said control port to communicate with each other, said movable member providing communication between said control port and said discharge port when not seated on said valve seat; an actuator (21) for driving said movable member; opening-closing means (14, 18) disposed in said internal passage of said movable member, operated to open said internal passage when said movable member is seated on said valve seat and operated to close said internal passage when said movable member is not seated on said valve seat; and reduction means (32, 42, 51, 61, 72) for reducing a gap formed between said slide bore and the outer peripheral surface of said movable member when said movable member is seated on said valve seat.

Claim 3

A three-way electromagnetic valve according to claim 1, wherein said gap formed between said slide bore (3) and the outer peripheral surface of said movable member (12) is created by penetration of the pressurized fluid between said slide bore and said movable member.

Claim 4

A three-way electromagnetic valve according to claim 2, wherein said reduction means includes a pressure accumulating chamber (32, 72) formed in said movable member to enable the pressurized fluid to deform said movable member by pressing the same outward in a radial direction from the interior thereof.

Claim 5

A three-way electromagnetic valve according to claim 2, wherein said pressure accumulating chamber is a larger-diameter chamber (31) formed in said internal passage of said movable member so as to extend in diametral directions.

Claim 6

A three-way electromagnetic valve according to claim 3, wherein the distance between said supply port and an end of said pressure accumulating chamber is set so that the extent of radially outward deformation of said movable member caused by the pressurized fluid in said pressure accumulating chamber is generally equal to the extent of radially outward deformation of said valve body caused by penetration of the pressurized fluid between said slide bore and the outer peripheral surface of said movable member.

Claim 7

A three-way electromagnetic valve according to claim 4, wherein the distance between said supply port and an end of said pressure accumulating chamber is set so that the extent of radially outward deformation of said movable member caused by the pressurized fluid in said pressure accumulating chamber is generally equal to the extent of radially outward deformation of said valve body caused by penetration of the pressurized fluid between said slide bore and the outer peripheral surface of said movable member.

Claim 8

A three-way electromagnetic valve according to claim 4, wherein the distance L₁ between said supply port (4) and said end of said pressure accumulating chamber (32) is about 20 to 40 % of the distance L between said supply port and a point at which the extent of radially outward deformation of said movable member caused by the pressurized fluid entering between said slide bore and the outer peripheral surface of said movable member is zero.

Claim 9

A three-way electromagnetic valve according to claim 2, wherein said reduction means includes a pressure accumulating chamber (32, 51, 72) formed in said valve body to enable the pressurized fluid to deform said valve body by pressing the same toward said slide bore.

Claim 10

A three-way electromagnetic valve according to claim 8, wherein said pressure accumulating chamber is a high pressure fluid passage (9, 42) formed in said valve body along a slide section between said slide bore (3) and said movable member (4) in the axial direction, a high pressure fuel being supplied through said high pressure fluid passage.

Claim 11

A three-way electromagnetic valve according to claim 9, wherein a plurality of supply ports (4) are formed in said valve body, and a plurality of fuel passages (19) facing said supply ports 4 are formed in said movable member (12) as part of said internal passage so as to extend in radial directions.

Claim 12

A three-way electromagnetic valve according to claim 10, wherein the distance L₂ between said supply port (4) and an end of said high pressure fluid passage (9, 42) end of said pressure accumulating chamber (32) is not smaller than about 50 % of the distance L between said supply port and a point at which the extent of radially outward deformation of said movable member caused by the high pressure fluid entering between said slide bore and the outer peripheral surface of said movable member is zero.

Claim 13

A three-way electromagnetic valve according to claim 11, wherein the distance L₂ between said supply port (4) and an end of said high pressure fluid passage (9, 42) end of said pressure accumulating chamber (32) is not larger than about 90 % of the distance L between said supply port and a point at which the extent of radially outward deformation of said movable member caused by the high pressure fluid entering between said slide bore and the outer peripheral surface of said movable member is zero.

Claim 14

A three-way electromagnetic valve according to claim 8, wherein said pressure accumulating chamber (72) is formed so as to communicates with said supply port.

Claim 15

A three-way electromagnetic valve according to claim 13, wherein a plurality of supply ports (4) are formed in said valve body, and a plurality of pressure accumulating chambers (72) are formed so as to face said supply ports (4) in radial directions.

Claim 16

A three-way electromagnetic valve according to claim 14, wherein the diameter D of said pressure accumulating chamber (72) is about 5 times larger than the diameter d of said supply port (4).

Claim 17

A three-way electromagnetic valve according to claim 8, wherein said pressure accumulating chamber is a cut groove (51) recessed in the axial direction and communicating with said supply port.

Claim 18

A three-way electromagnetic valve according to claim 1, wherein an outer peripheral portion of an upper surface of said valve body is integrally fixed to said actuator by being fastened thereto, and this fastening creates a gap between said slide bore and the outer peripheral surface of said movable member.

Claim 19

A three-way electromagnetic valve according to claim 17, wherein said reduction means includes an annular groove (61) formed around said slide bore.

Claim 20

A three-way electromagnetic valve according to claim 18, wherein the depth L₃ of said annular groove (61) from the upper surface of said valve body (2) is about 30 to 100 % of the distance L between the upper surface of said valve body and said supply port.

Claim 21

A three-way electromagnetic valve comprising: a valve body (2) having a supply port (4) through which a pressurized fluid flows, a control port (5), a discharge port (6), a slide bore (3) formed with said ports so as to communicate with the same, and a valve seat (5a) formed between said supply port and said discharge port; a movable member (12) slidably disposed in said slide bore and capable of contacting and moving away from said valve seat, said movable member having an internal passage (17) formed in its body to enable said supply port and said control port to communicate with each other, said movable member providing communication between said control port and said discharge port when not seated on said valve seat; an actuator (21) for driving said movable member; opening-closing means (14, 18) disposed in said internal passage of said movable member, operated to open said internal passage when said movable member is seated on said valve seat and operated to close said internal passage when said movable member is not seated on said valve seat; and pressure accumulation chamber means (32, 42, 51, 61, 72) for maintaining part of the pressurized fluid for balancing with pressure deformation caused by penetration of the pressurized fluid between said slide bore and the outer peripheral surface of said movable member when said movable member is seated on said valve seat.

Claim 22

A three-way electromagnetic valve comprising: a valve body (2) having a supply port (4) through which a pressurized fluid flows, a control port (5), a discharge port (6), a slide bore (3) formed with said ports so as to communicate with the same, and a valve seat (5a) formed between said supply port and said discharge port; a movable member (12) slidably disposed in said slide bore and capable of contacting and moving away from said valve seat, said movable member having an internal passage (17) formed in its body to enable said supply port and said control port to communicate with each other, said movable member providing communication between said control port and said discharge port when not seated on said valve seat; an actuator (21) for driving said movable member; opening-closing means (14, 18) disposed in said internal passage of said movable member, operated to open said internal passage when said movable member is seated on said valve seat and operated to close said internal passage when said movable member is not seated on said valve seat; and pressure accumulation chamber means (32, 42, 51, 61, 72) for maintaining part of the pressurized fluid for balancing with pressure deformation caused by penetration of the pressurized fluid between said slide bore and the outer peripheral surface of said movable member when said movable member is seated on said valve seat.

Claim 23

A three-way electromagnetic valve according to claim 20, wherein said pressure accumulation chamber means (32) is formed in said movable member (12).

Claim 24

A three-way electromagnetic valve according to claim 20, wherein said pressure accumulation chamber means (42, 51, 61, 72) is formed in said valve body (2).

Claim 25

A three-way electromagnetic valve according to claim 20, wherein said pressure accumulation chamber means includes a plurality of fluid passages (31).

Claim 26

A three-way electromagnetic valve comprising: a valve body (2) having a supply port (4) through which a pressurized fluid flows, a control port (5), a discharge port (6), a slide bore (3) formed with said ports so as to communicate with the same, and a valve seat (5a) formed between said supply port and said discharge port; a movable member (12) slidably disposed in said slide bore and capable of contacting and moving away from said valve seat, said movable member having an internal passage (17) formed in its body to enable said supply port and said control port to communicate with each other, said movable member providing communication between said control port and said discharge port when not seated on said valve seat; an actuator (21) for driving said movable member; opening-closing means (14, 18) disposed in said internal passage of said movable member, operated to open said internal passage when said movable member is seated on said valve seat and operated to close said internal passage when said movable member is not seated on said valve seat; fixing means (25) for fastening and fixing one end surface of said valve body to said actuator; and an annular groove (61) formed in said valve body around said slide bore.

Claim 27

A three-way electromagnetic valve comprising: a valve body (2) having a supply port (4) through which a pressurized fluid flows, a control port (5), a discharge port (6), a slide bore (3) formed with said ports so as to communicate with the same, and a valve seat (5a) formed between said supply port and said discharge port; a movable member (12) slidably disposed in said slide bore and capable of contacting and moving away from said valve seat, said movable member having an internal passage (17) formed in its body to enable said supply port and said control port to communicate with each other, said movable member providing communication between said control port and said discharge port when not seated on said valve seat; an actuator (21) for driving said movable member; opening-closing means (14, 18) disposed in said internal passage of said movable member, operated to open said internal passage when said movable member is seated on said valve seat and operated to close said internal passage when said movable member is not seated on said valve seat; fixing means (25) for fastening and fixing one end surface of said valve body to said actuator; and an annular groove (61) formed in said valve body around said slide bore.

Claim 28

A three-way electromagnetic valve according to claim 21, further comprising a pressure accumulation chamber means for maintaining part of the pressurized fluid for balancing with pressure deformation caused by penetration of the pressurized fluid between said slide bore and the outer peripheral surface of said movable member when said movable member is seated on said valve seat.