Abstract: A movable valve element (24) is comprised of a valve member (22) and a leaf spring (26). A passage forming member (12) is securely fixed to a valve chamber forming member (10) that forms a valve chamber (S). The passage forming member (12) has a fluid passage (14) extending from one end to the other end thereof, with the one end (14a) of the fluid passage (14) constituting an outlet port of the valve chamber (S). The passage forming member (12) has an O-ring (20) surrounding and spaced apart from the outlet port (14a), the O-ring (20) constituting a valve seat. Spring force of the leaf spring (26) brings the valve member (22) into pressure contact with the O-ring (20), to form a closed valve state.

Abstract: A flow control restrictor includes: a needle valve; and a limit cap which is made of metal and attached to the needle valve. In the needle valve, a first shaft portion which is made of metal and screwed into a regulation hole and a second shaft portion which is made of metal and housed inside the regulation hole are formed. On the second shaft portion, a first projection-and-recess portion is formed, and a pressed portion made of resin is provided on the first shaft portion side relative to the first projection-and-recess portion. The limit cap is fitted onto the second shaft portion. On the limit cap, a projecting portion which is inserted into a restriction groove of the regulation hole and a second projection-and-recess portion which is engaged with the first projection-and-recess portion are formed. The pressed portion is pressed against an inner peripheral surface of the limit cap.

Abstract: A fuel regulator includes a limit cap which is attached to a needle valve which is inserted into a regulation hole. In an inner peripheral surface of a second hole portion of the regulation hole, a restriction groove and a guide groove which extends from the restriction groove through an outer surface of a main body portion in an axial direction of the second hole portion are formed. A projecting portion which is inserted into the restriction groove is formed on an outer peripheral surface of the limit cap, and the projecting portion is capable of passing through the guide groove, and in the main body portion, a cast hole which extends from the restriction groove through the outer surface of the main body portion in a direction intersecting the axial direction of the second hole portion is formed.

Abstract: A limiting cap is provided to restrict rotation of a needle valve and to be easily assembled onto the needle cap. The limiting cap assembled onto the needle valve screwed into an adjustment hole of a fuel adjuster includes a main body to be arranged onto the needle valve. A rising part, which is inserted into a recess of the fuel adjuster, is formed on an outer peripheral surface of the main body. The main body includes a first engagement part on an inner side and a fixing part on an outer side. A first hubbly part formed in an inner peripheral surface of the first engagement part is engageable with a second hubbly part formed in an outer peripheral surface of the needle valve. The needle valve is fixed into the fixing part. The fixing part is formed to have a smaller inner diameter than the first engagement part.

Abstract: A needle valve body (220) has a needle hollow part (230) and a slit (232) extending in an axial direction and opened forward in a tip region. The carburetor body (B) has a body hole (202) receiving the needle valve body (220) in a longitudinally displaceable manner along an axis and a step-part circumferential edge (240a) formed in the body hole (202) and forming an orifice (250) with the slit (232) of the needle valve body (220). By operating the needle valve body (220) to adjust the size of the orifice (250), an amount of fuel supplied to a fuel discharge part (Fout) can be adjusted.

Abstract: A limiting cap is provided to restrict rotation of a needle valve and to be easily assembled onto the needle cap. The limiting cap assembled onto the needle valve screwed into an adjustment hole of a fuel adjuster includes a main body to be arranged onto the needle valve. A rising part, which is inserted into a recess of the fuel adjuster, is formed on an outer peripheral surface of the main body. The main body includes a first engagement part on an inner side and a fixing part on an outer side. A first hubbly part formed in an inner peripheral surface of the first engagement part is engageable with a second hubbly part formed in an outer peripheral surface of the needle valve. The needle valve is fixed into the fixing part. The fixing part is formed to have a smaller inner diameter than the first engagement part.

Abstract: A needle valve body (220) has a needle hollow part (230) and a slit (232) extending in an axial direction and opened forward in a tip region. The carburetor body (B) has a body hole (202) receiving the needle valve body (220) in a longitudinally displaceable manner along an axis and a step-part circumferential edge (240a) formed in the body hole (202) and forming an orifice (250) with the slit (232) of the needle valve body (220). By operating the needle valve body (220) to adjust the size of the orifice (250), an amount of fuel supplied to a fuel discharge part (Fout) can be adjusted.

Abstract: An amount of air taken into an air leading type two-stroke engine is increased to enhance an engine output, and gas emission characteristic deterioration caused by blow-back is inhibited. An inhibition member 16 is disposed between a choke valve 4 in a full open position and a throttle valve 6 in a full open position. The inhibition member 16 includes, for example, a mesh member like a metal mesh. Mixed fuel containing oil is supplied to the air-fuel mixture channel 14. Numerous pores of the inhibition member 16 (mesh member) are occluded by a membrane of oil components of the mixed fuel. Consequently, entry of a blow-back flow of an air-fuel mixture from the air-fuel mixture channel 14 into the air channel 12 through the numerous pores of the flow inhibition member 16 (mesh member) can be inhibited.

Abstract: A rotary-type carburetor (1) according to the present invention includes a body (4) having a bore (2) with a circular cross section, and a valve element (6) to be contained in the bore (2). The valve element (6) rotates between a closed position where the valve passage (16) is blocked from communicating with the body passages (10a, 10b), and a fully-opened position where the valve passage (16) and the body passages (10a, 10b) are aligned. When the valve element (6) is located in an idle position, an air flowing through the body passages (10a, 10b) and the valve passage (16) is prevented from being flown into the bore end part (12). When the valve element (6) is located in a fully-opened position, a portion of the air flowing from an upstream part (10a) of the body passage is bypassed into the upstream communication part (32).

Abstract: An amount of air taken into an air leading type two-stroke engine is increased to enhance an engine output, and gas emission characteristic deterioration caused by blow-back is inhibited. An inhibition member 16 is disposed between a choke valve 4 in a full open position and a throttle valve 6 in a full open position. The inhibition member 16 includes, for example, a mesh member like a metal mesh. Mixed fuel containing oil is supplied to the air-fuel mixture channel 14. Numerous pores of the inhibition member 16 (mesh member) are occluded by a membrane of oil components of the mixed fuel. Consequently, entry of a blow-back flow of an air-fuel mixture from the air-fuel mixture channel 14 into the air channel 12 through the numerous pores of the flow inhibition member 16 (mesh member) can be inhibited.

Abstract: A rotary-type carburetor (1) according to the present invention includes a body (4) having a bore (2) with a circular cross section, and a valve element (6) to be contained in the bore (2). The valve element (6) rotates between a closed position where the valve passage (16) is blocked from communicating with the body passages (10a, 10b), and a fully-opened position where the valve passage (16) and the body passages (10a, 10b) are aligned. When the valve element (6) is located in an idle position, an air flowing through the body passages (10a, 10b) and the valve passage (16) is prevented from being flown into the bore end part (12). When the valve element (6) is located in a fully-opened position, a portion of the air flowing from an upstream part (10a) of the body passage is bypassed into the upstream communication part (32).