1-29. (canceled)
30. A vehicle seat comprising a seat cushion and a seat back, wherein
the seat cushion is given a stiffness distribution in a front-rear direction in such a way that a front part of the seat cushion is provided with a low stiffness region which is more flexible than a rear part of the seat cushion being a high stiffness region,
the seat back is given a stiffness distribution having different reaction force characteristics in a vertical direction of the seat back in such a way that a low stiffness region having a small support reaction force for the occupant is set in a vertical center portion of the seat back while high stiffness regions each having a large support reaction force for the occupant are set, adjacent to the low stiffness region, in upper and lower portions of the seat back, and
the backrest surface of the seat back is bendable in the middle at the low stiffness region at any of various middle bend angles according a backrest load of the occupant.
31. The vehicle seat according to claim 30, wherein
the low stiffness region of the seat cushion is given reaction force characteristics of having a large support reaction force for a seating load applied from the above, and a small support reaction force for a seating load applied from the front.
32. The vehicle seat according to claim 30, wherein
the low stiffness region of the seat cushion is set in a lower posterior thigh contact portion to be in contact with the lower posterior thighs of the occupant, a posterior knee contact portion to be in contact with the posterior knees of the occupant, and a posterior lower leg contact portion to be in contact with the posterior lower legs of the occupant, and
the reaction force characteristics of the low stiffness region of the seat cushion are set such that support reaction forces of the respective lower posterior thigh contact portion, posterior knee contact portion and posterior lower leg contact portion satisfy a relation of the lower posterior thigh contact portion>the posterior knee contact portion>the posterior lower leg contact portion.
33. The vehicle seat according to claim 32, wherein
the seat cushion is formed of at least two parts which are the rear part and the front part including a front end portion thereof, and
the front part is formed of a pad material having the reaction force characteristics.
34. The vehicle seat according to claim 30, wherein
the high stiffness region set in the upper portion of the seat back is formed to substantially correspond to the chest of the occupant, and
the high stiffness region set in the lower portion of the seat back is formed to substantially correspond to the pelvis of the occupant.
35. The vehicle seat according to claim 30, wherein
the low stiffness region set in the vertical center portion of the seat back is formed to have its center at a portion substantially corresponding to a joint between the chest and the waist of the occupant.
36. The vehicle seat according to claim 30, wherein
the seat back includes a cushion pad to elastically support the occupant, and
in the cushion pad, a groove to facilitate middle bending of the cushion pad is formed to extend in a vehicle width direction at a vertical center portion of the low stiffness region of the seat back.
37. The vehicle seat according to claim 36, wherein
the seat back includes a pad supporting member to support the cushion pad on a seat back frame at a back side of the cushion pad, and
the high stiffness regions and the low stiffness region of the seat back are set by providing the pad supporting member with different mechanical properties of stiffness and softness.
38. The vehicle seat according to claim 32, wherein
the front part of the seat cushion is made of a pad material in which portions corresponding to the lower posterior thigh contact portion, the posterior knee contact portion and the posterior lower leg contact portion have different spring constants.
39. The vehicle seat according to claim 38, wherein
the pad material used in the portion corresponding to the lower posterior thigh contact portion includes a plurality of pad materials divided in a front-rear direction, and
the spring constant of the pad material arranged on a rear side is set smaller than the spring constant of the pad material arranged on a front side.
40. The vehicle seat according to claim 32, wherein
the reaction force characteristics are imparted in such a way that:
the front part of the seat cushion is made of a pad material having a smaller spring constant than a pad material used in the rear part of the seat cushion; and
a parting line along which the pad materials of the front and rear parts of the seat cushion face and contact each other is extended from around the boundary between the lower posterior thigh contact portion and the posterior knee contact portion and is inclined downwardly toward the rear.
41. The vehicle seat according to claim 32, wherein
the reaction force characteristics are imparted in such a way that:
the front part of the seat cushion is made of a pad material having a smaller spring constant than a pad material used in the rear part of the seat cushion;
a load receiving member is provided to a front portion of a seat cushion frame member, the load receiving member protruding upward in the low stiffness region; and
a thickness of the pad material in the front part of the seat cushion is adjusted by using an upper side and a front side of the load receiving member.
42. The vehicle seat according to claim 32, wherein
the reaction force characteristics are imparted in such a way that:
the front part of the seat cushion is made of a pad material having a smaller spring constant than a pad material used in the rear part of the seat cushion;
a load receiving member is provided to a front portion of a seat cushion frame member, the load receiving member protruding upward in the low stiffness region;
a thickness of the pad material in the front part of the seat cushion is adjusted by using an upper side and a front side of the load receiving member; and
a spring mechanism is provided to the front side of the load receiving member, the spring mechanism being capable of retreating rearward in response to a seating load acting from the front.
43. The vehicle seat according to claim 32, wherein
the seat cushion is made of a single pad material, and
a hollow portion is provided in the front part of the pad material to form the low stiffness region in the seat cushion and to impart the reaction force characteristics to the low stiffness region.
44. The vehicle seat according to claim 30, comprising:
an inclined surface provided at a corner region where the seating surface of the seat cushion and the backrest surface of the seat back are joined to each other, the inclined surface configured to support the hip of the occupant.
45. The vehicle seat according to claim 44, wherein
an intersection between the inclined surface and the seating surface of the seat cushion is set at a position slightly behind the ischial tuberosity in the pelvis of the occupant, and
an intersection between the inclined surface and the backrest surface of the seat back is set at a position corresponding to the vicinity of the sacrum in the pelvis of the occupant.
46. The vehicle seat according to claim 44, wherein
the inclined surface is formed of a protruding portion formed integral with any one of the seat cushion and the seat back.
47. The vehicle seat according to claim 44, wherein
the inclined surface is formed of an elastic band-shaped member laid between the seating surface of the seat cushion and the backrest surface of the seat back across the corner region.
48. The vehicle seat according to claim 30, comprising:
the seating surface of the seat cushion is set such that adjacent portions in the seating surface are different from each other in at least one of stiffness, friction coefficient and shape.
49. The vehicle seat according to claim 48, wherein
the seating surface of the seat cushion is configured such that
a portion in front of a maximum deformation part in seating has a lower friction coefficient against sliding from the front to the rear than a friction coefficient against sliding from the rear to the front, and
a portion behind the maximum deformation part has a lower friction coefficient against sliding from the rear to the front than a friction coefficient against sliding from the front to the rear.
50. The vehicle seat according to claim 48, wherein
the seating surface of the seat cushion is configured such that a surface layer in a portion in front of a maximum deformation part in seating is softer than a surface layer of a portion behind the maximum deformation part.
51. The vehicle seat according to claim 48, wherein
the seating surface of the seat cushion is formed such that a surface of a portion behind a maximum deformation part in seating is substantially horizontal.
52. The vehicle seat according to claim 48, wherein
the seating surface of the seat cushion is formed such that a surface of a portion in front of a maximum deformation part in seating inclines downwardly toward the rear.
53. The vehicle seat according to claim 30, wherein
the backrest surface of the seat back is set such that adjacent portions in the backrest surface are different from each other in at least one of stiffness, friction coefficient and shape.
54. The vehicle seat according to claim 53, wherein
the backrest surface of the seat back is set such that a friction coefficient of a portion corresponding to the chest of the occupant is higher than a friction coefficient of a portion below the portion corresponding to the chest.
55. The vehicle seat according to claim 53, wherein
the backrest surface of the seat back is configured such that a surface layer of a portion corresponding to the chest of the occupant is softer than a surface layer of a portion below the portion corresponding to the chest.
56. The vehicle seat according to claim 53, wherein
in the backrest surface of the seat back, an inclination angle of an upper portion is larger than an inclination angle of a lower portion.
57. A stiffness setting method for a vehicle seat including a seat cushion and a seat back, the method comprising:
giving the seat cushion a stiffness distribution in a front-rear direction in such a way that a front part of the seat cushion is provided with a low stiffness region which is more flexible than a rear part of the seat cushion being a high stiffness region;
giving the seat back a stiffness distribution having different reaction force characteristics in a vertical direction of the seat back in such a way that a low stiffness region having a small support reaction force for the occupant is set in a vertical center portion of the seat back while high stiffness regions each having a large support reaction force for the occupant are set, adjacent to the low stiffness region, in upper and lower portions of the seat back; and
making the backrest surface of the seat back bendable in the middle at the low stiffness region at any of various middle bend angles according a backrest load of the occupant when the backrest surface receives the back of the occupant arriving after moving backward on the high stiffness region of the seat cushion.
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. An immersion heater comprising a ceramic bottomed protecting tube, an insulating cylindrical body inserted into said ceramic bottomed protecting tube, a metal heating element held inside a spiral groove formed in an outer circumference surface of said insulating cylindrical body, an insulating cover closing an opening portion of said ceramic bottomed protecting tube, and first and second terminal rods, one-end portions of which are connected to a fore-end portion and a back-end portion of said metal heating element, respectively, and other-end portions of which pass through said insulating cover and are located outside said ceramic bottomed protecting tube, wherein:
said metal heating element is a strip heating element, and one edge portion of said strip heating element is inserted into, and held in said spiral groove to form a spiral heating part,
cylindrical-body supporting members that each have a diameter smaller than an inner diameter of said ceramic bottom protecting tube and larger than an outer diameter of the spiral heating part and are fitted into a hollow portion of said insulating cylindrical body are arranged in openings at a fore-end side and a back-end side of said insulating cylindrical body, respectively,
a through-hole through which said first terminal rod connected to the fore-end portion of said metal heating element passes, and a notched portion through which a connection plate joined and fixed to a fore-end of said first terminal rod is inserted are formed in said cylindrical-body supporting member on the fore-end side, and
a through-hole through which said first terminal rod passes, and a notched portion through which a connection plate joined and fixed to a fore-end of said second terminal rod is inserted are formed in said cylindrical-body supporting member on the back-end side.
2. The immersion heater according to claim 1, wherein a space between said cylindrical-body supporting member on the back-end side and said cover inside said protecting tube is packed with a thermal insulator.
3. The immersion heater according to claim 1, wherein an outer circumference portion on an opening end portion side of said ceramic bottomed protecting tube is formed into a taper shape that is tapered toward a fore-end thereof.
4. The immersion heater according to claim 1, wherein said terminal rod fixed to said cylindrical-body supporting member on the fore-end side so as to be connected to the fore-end portion of said metal heating element passes through said cylindrical body, said cylindrical-body supporting member on the back-end side and said cover to extend, and wherein a compression spring is arranged between a fastener provided in said terminal rod and said cover outside said cover.
5. The immersion heater according to claim 1, wherein said terminal rod connected to the fore-end portion of said metal heating element is formed into a pipe shape, and a thermocouple is inserted into, and arranged in said pipe-shaped terminal rod.
6. The immersion heater according to claim 5, wherein a fore-end opening of said pipe-shaped terminal rod is packed with a thermal insulator.
7. The immersion heater according to claim 1, wherein an insulating cylindrical spacer is arranged between said cylindrical-body supporting member on the back-end side and said cover in a state where said insulating cylindrical spacer contains said terminal rod.
8. The immersion heater according to claim 1, wherein a plurality of through-openings are formed in a wall of said insulating cylindrical body.
9. An immersion heater comprising a ceramic bottomed protecting tube, an insulating cylindrical body inserted into said ceramic bottomed protecting tube, a metal heating element held inside a spiral groove formed in an outer circumference surface of said insulating cylindrical body, an insulating cover closing an opening portion of said ceramic bottomed protecting tube, and first and second terminal rods, one-end portions of which are connected to a fore-end portion and a back-end portion of said metal heating element, respectively, and other-end portions of which pass through said insulating cover and are located outside said ceramic bottomed protecting tube, wherein:
said metal heating element is a strip heating element, and one edge portion of said strip heating element is inserted into, and held in said spiral groove to form a spiral heating part,
cylindrical-body supporting members that each have a diameter smaller than an inner diameter of said ceramic bottom protecting tube and larger than an outer diameter of the spiral heating part and are fitted into a hollow portion of said insulating cylindrical body are arranged in openings at a fore-end side and a back-end side of said insulating cylindrical body, respectively, and
said terminal rod connected to the fore-end portion of said metal heating element is formed into a pipe shape, and a thermocouple is inserted into, and arranged in said pipe-shaped terminal rod.
10. The immersion heater according to claim 9, wherein a fore-end opening of said pipe-shaped terminal rod is packed with a thermal insulator.
11. An immersion heater comprising a ceramic bottomed protecting tube, an insulating cylindrical body inserted into said ceramic bottomed protecting tube, a metal heating element held inside a spiral groove formed in an outer circumference surface of said insulating cylindrical body, an insulating cover closing an opening portion of said ceramic bottomed protecting tube, and first and second terminal rods, one-end portions of which are connected to a fore-end portion and a back-end portion of said metal heating element, respectively, and other-end portions of which pass through said insulating cover and are located outside said ceramic bottomed protecting tube, wherein:
said metal heating element is a strip heating element, and one edge portion of said strip heating element is inserted into, and held in said spiral groove to form a spiral heating part,
cylindrical-body supporting members that each have a diameter smaller than an inner diameter of said ceramic bottom protecting tube and larger than an outer diameter of the spiral heating part and are fitted into a hollow portion of said insulating cylindrical body are arranged in openings at a fore-end side and a back-end side of said insulating cylindrical body, respectively, and
an insulating cylindrical spacer is arranged between said cylindrical-body supporting member on the back-end side and said cover in a state where said insulating cylindrical spacer contains said terminal rod.