What is claimed is:
1. A valve seat, press-fitted into a cylinder head of an internal combustion engine, containing an iron-based sintered alloy, comprising:
a valve-seating section; and
a head-seating section,
wherein the valve-seating section and the head-seating section are monolithically formed by a sintering process and form a double layer structure, the valve-seating section includes a first iron-based sintered alloy member that has a porosity of 10 to 25 percent by volume and a sintered density of 6.1 to 7.1 gcm3 and contains hard particles dispersed in a matrix phase, and the head-seating section includes a second iron-based sintered alloy member that has a porosity of 10 to 20 percent by volume and a sintered density of 6.4 to 7.1 gcm3.
2. The valve seat according to claim 1, wherein the hard particles contain at least one selected from the group consisting of C, Cr, Mo, Co, Si, Ni, S, and Fe, and the content of the hard particles in the first iron-based sintered alloy member is 5 to 40 percent by area.
3. The valve seat according to claim 1 or 2, wherein the matrix phase and hard particles form a base portion; the base portion contains 10.0 to 40.0 percent by mass of at least one selected from the group consisting of Ni, Cr, Mo, Cu, Co, V, Mn, W, C, Si, and S, the Ni content being 2.0 to 23.0%, the Cr content being 0.4 to 15.0%, the Mo content being 3.0 to 15.0%, the Cu content being 0.2 to 3.0%, the Co content being 3.0 to 15.0%, the V content being 0.1 to 0.5%, the Mn content being 0.1 to 0.5%, the W content being 0.2 to 6.0%, the C content being 0.8 to 2.0%, the Si content being 0.1 to 1.0%, the S content being 0.1 to 1.0% on a mass basis, the balance being substantially Fe; and the matrix phase of the second iron-based sintered alloy member contains 0.3-15.0 percent by mass of at least one selected from the group consisting of C, Ni, Cr, Mo, Cu, Co, V, and Mn, the balance being substantially Fe.
4. The valve seat according to any one of claims 1 to 3, wherein the first and second iron-based sintered alloy members further contain 0.3 to 3.5 percent by area of solid lubricant particles dispersed in the matrix phase.
5. The valve seat according to claim 4, wherein the solid lubricant particles contain at least one selected from the group consisting of a sulfide, and a fluoride.
6. A method for manufacturing a valve seat containing an iron-based sintered alloy, comprising:
a forming step of filling a first raw material powder for forming a valve-seating section and a second raw material powder for forming a head-seating section into a metal mold one after another such that the first and second raw material powders form a double layer structure and then compacting the resulting first and second raw material powders to form a green compact consisting of two layers; and
a sintering step of heating the resulting green compact in a protective atmosphere to obtain a sintered body having a double layer construction,
wherein the first raw material powder contains 20 to 70% of a pure iron powder, 10 to 50% of a first ferroalloy powder, and 5 to 40% of a hard particle powder on a mass basis or further contains 0.2 to 3.0 parts by weight of a solid lubricant particle powder with respect to 100 parts by weight of the first raw material powder, the pure iron powder, first ferroalloy powder, and hard particle powder or solid lubricant particle powder being blended and mixed; the first ferroalloy powder contains 3 to 30 percent by mass of at least one selected from the group consisting of Ni, Cr, Mo, Cu, Co, V, Mn, W, and C, the balance being substantially Fe; the hard particle powder contains at least one selected from the group consisting of C, Cr, Mo, Co, Si, Ni, S, and Fe; the second raw material powder contains 85% or more of the pure iron powder and 0.3 to 15% of a second ferroalloy powder on a mass basis or further contains 0.2 to 3.0 parts by weight of the solid lubricant particle powder with respect to 100 parts by weight of the second raw material powder, the pure iron powder and second ferroalloy powder or solid lubricant particle powder being blended and mixed; the second ferroalloy powder contains at least one selected from the group consisting of C, Ni, Cr, Mo, Cu, Co, V, and Mn; and conditions of the forming step and sintering step are adjusted such that the first iron-based sintered alloy member has a sintered density of 6.1 to 7.1 gcm3 and a porosity of 10 to 25 percent by volume and the second iron-based sintered alloy member has a sintered density of 6.4 to 7.1 gcm3 and a porosity of 10 to 20 percent by volume.
7. The method according to claim 6, wherein the first raw material powder contains 0.3 to 15 percent by mass of an alloy element powder instead of part or the whole of the ferroalloy powder, and the alloy element powder contains at least one selected from the group consisting of Ni, Cr, Mo, Cu, Co, V, Mn, W, and C.
The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.
1. A lighting apparatus comprising:
a body including a substrate, a light emitting module with a light emitting diode (LED) mounted to the substrate, and a heat sink to dissipate heat from the light emitting module;
a support member to support the body at a plurality of different tilt positions relative to the support member, the support member including an end portion; and
a connection member provided to the body to connect the body to the support member, the connection member including a first projection that extends to a first height and a second projection that extends to a second height,
wherein the body is provided in a first tilt position relative to the support member when the first projection contacts the end portion of the support member without the second projection contacting the support member, and the body is provided in a second tilt position relative to the support member when the second projection contacts the end portion of the support member,
wherein the support member includes a first surface to face an inner surface of the connection member, and a second surface,
wherein when the body is in the first tilt position relative to the support member, the first projection contacts the second surface of the support member without the second projection contacting the support member, and
when the body is in the second tilt position relative to the support member, the first projection contacts the first surface of the support member and the second projection contacts the second surface of the support member.
2. The lighting apparatus of claim 1, wherein the light emitting module to provide light in a first direction when the body is in the first tilt position relative to the support member, and the light emitting module to provide light in a second direction when the body is in the second tilt position relative to the support member.
3. The lighting apparatus of claim 1, wherein the first projection and the second projection each project inwardly from an inner surface of the connection member.
4. The lighting apparatus of claim 3, wherein the first projection is provided further away from the body than the second projection, and the second height of the second projection is greater than the first height of the first projection.
5. The lighting apparatus of claim 1, wherein the end portion of the support member is provided in a space of the connection member.
6. The lighting apparatus of claim 1, wherein the second projection prevents the support member from entering into the body when the support member is provided in the connection member at a predetermined tilt angle.
7. The lighting apparatus of claim 1, further comprising:
a screw movable inout of the connection member so as to be in contact with the support member provided in the connection member, and
a stopper in the connection member to prevent the support member from entering into the body.
8. The lighting apparatus of claim 1, wherein the connection member further includes:
an upper housing;
a middle cover coupled to the upper housing to support the support member; and
a lower housing mounted to the upper housing to surround the middle cover and to form a predetermined space therein.
9. The lighting apparatus of claim 8, wherein the upper housing is formed with the body as one unit.
10. The lighting apparatus of claim 8, wherein a plurality of additional projections extend from an inner surface of the middle cover.
11. The lighting apparatus of claim 8, wherein the middle cover is fastened to the upper housing with a screw such that the middle cover is spaced from the upper housing by a predetermined distance.
12. The lighting apparatus of claim 1, further comprising:
a power supply unit to electrically connect to the light emitting module, and
a cable electrically connected to the power supply unit by passing through the connection member.
13. A lighting apparatus comprising:
a body including a substrate, and a light emitting module mounted to the substrate, the light emitting module including a light emitting diode (LED);
a connection member attached to the body, the connection member including a first projection that extends from an inner surface to a first height and a second projection that extends from the inner surface to a second height; and
a support member to couple to the connection member and support the body, the support member including an end portion, wherein the support member includes a first surface and a second surface, the first surface to face an inner surface of the connection member when the end portion extends into the connection member, wherein when the body is in a first tilt position relative to the support member, the second surface of the support member contacts the first projection without contacting the second projection, and when the body is in a second tilt position relative to the support member, the first surface of the support member contacts the first projection and the second surface of the support member contacts the second projection,
wherein when the body is provided in the first tilt position relative to the support member, the light emitting module provides light in a first direction, and when the body is provided in a second tilt position relative to the support member, the light emitting module provides light in a second direction.
14. The lighting apparatus of claim 13, wherein the second projection prevents the support member from entering further into the body when the support member is provided in the connection member at a predetermined tilt angle.
15. The lighting apparatus of claim 13, further comprising:
a screw to be provided in the connection member so as to be in contact with the support member provided in the connection member, and
a stopper in the connection member to prevent the support member from entering into the body.
16. The lighting apparatus of claim 13, wherein the connection member further includes:
an upper housing;
a middle cover coupled to the upper housing to support the support member; and
a lower housing mounted to the upper housing to surround the middle cover and to form a predetermined space therein.
17. The lighting apparatus of claim 16, wherein the upper housing is formed with the body as one unit.
18. The lighting apparatus of claim 16, wherein a plurality of additional projections extend from an inner surface of the middle cover.
19. The lighting apparatus of claim 13, further comprising:
a power supply unit to electrically connect to the light emitting module; and
a cable electrically connected to the power supply unit by passing through the connection member.