A TAKEDOWN STAIRCASE

Abstract: A takedown staircase in which the upward joint 2 and the down­ ward joint 3 are vertically installed at the base end and front end of horizontal base plate 1, comprises a stair unit 4 which will be connected to a plurality of upper and lower flights by mutually inserting/uniting the upward joint 2 and the downward joint 3, a bolt 7 which fixes the upward joint 2 and the down­ ward joint 3 by being spirally inserted into a nut 6 fixedly installed in the downward joint 3 from a longitudinal long hole 5 bored in the upward joint 2 and a tread 8 which will be fixed to the upper surface of horizontal base plate 1.

Description: The present invention relates to a takedown staircase formed by connection a stair unit to a plurality of upper and lower stair units for use in a flight of steps for use in a house or in a store. The prior takedown staircase disclosed in the Japanese Patent specification No. 62-13459 (or EP-A-0 106 125) comprises a cylindrical upward joint part and a cylindrical downward joint part which are vertically installed at the base end and front end of horizontal base plate respectively, a stair unit connected to a plurality of upper and lower stair units by uniting an upward joint part and a downward joint part, a fixing plate welded horizontally within the downward joint part and provided vertically with a transparrent hole in its center, a movable case connected to the end of upward joint part and inserted rotatably into the downward joint part to move up and down together with the upward joint part, a covering plate welded horizontally to the movable case and provided with a nut welded to its center, a bolt spirally inserted into the nut from the said transparent hole to fix the fixing plates of upper and lower stair units and the covering plate, and a tread fixed to the upper surface of each horizontal base plate. Referring to the prior staircase disclosed in the Japanese Patent Specification No. 62-13460 (or EP-A-0 306 776), a stair unit is used, wherein a cylindrical upward joint part and a cylindrical downward joint part are vertically installed at the base end and front end of the horizontal base plate respectively, a fixing bolt is vertically installed in the upper central part of upward joint part and a horizontal seating plate is fixed within the downward joint part, and the upward and downward joint parts of upper and lower stair units which are rotatably inserted/united are fixed by holding the horizontal seating plate between the upper and lower nuts which are spirally united with the said bolt. Such a staircase as described hereinabove requires a fixing plate, a movable case and a covering plate in addition to an upward joint, a downward joint and a connection bolt as parts necessary to connect an upper stair unit and a lower stair unit. Thus, it requires a large number of constituent parts, and weighs more than it should. Also, it takes time and requires more efforts because it entails the welding of fixing plate to the downward joint, the screwing of movable case and upward joint, the screwing of covering plate to the movable case and the welding of nut to covering plate. In addition, it requires an assistant worker for holding a stair unit at a position where it is to be installed while an angle at which the upper and lower stair units are to be placed is adjusted by giving a turn and fixed by the bolt because the cylindrical upward and downward joints must be inserted/united rotatably. Fitting of stair units is also troublesome and labor cost is thereby made to go up. Furthermore, as bolts and nuts are arranged on the longitudinal central line of upward and downward joints, the upward and downward joints can be made rotatable when a bolt is loosened by an unknown cause, and the fixed condition of upper and lower stair units will be distorted and the staircase may thereby tremble dangerously. In the takedown staircase suggested in the latter, the fixing bolt is placed on the longitudinal central line of upward joint. So, when the bolt is loosened by an unaccountable cause, the upward and downward joints can be made roratable, and the fixed condition of upper and lower stair units will be distorted and the staircase may thereby tremble. A takedown staircase can be formed of reduced cost and weight thanks to a small number of constituent parts and efficiency of work thanks to its reduced number of parts to be welded. An object of the present invention is to provide a takedown staircase which can be prevented from trembling dnagerously by avoiding rotation between the upward and downward joints. According to a first aspect of the present invention there is provided a stair unit adapted for attachment to further stair units so as to form a staircase, which stair unit comprises: a base plate arranged to extend horizontally in an assembled staircase; a first joint part upstanding from a rear portion of the base plate; a second joint part depending from a front portion of the base plate, said upstanding and depending joint parts being arranged to mate with similar joint parts of further stair units, said upstanding joint part with a depending joint part of an upper further stair unit, and said depending joint part with an upstanding joint part of a lower further stair unit; and a tread part for fixing to an upper surface of the base plate; characterised in that there is defined in said upstanding joint part, a hole which is elongate in the upstanding direction; and in that there is a nut fixedly mounted on said depending joint part; wherein the depending joint part of one unit is securable to the upstanding joint part of another unit by means of a bolt extending through the elongate hole of the upstanding part and screwed into a nut of the depending part; and in that the joint parts are of non-circular transverse section, whereby on mating with the joint parts of further units, relative rotation is prevented. According to a second aspect of the present invention there is provided a stair unit adapted for attachment to further stair units so as to form a staircase, which stair unit comprises: a base plate arranged to extend horizontally in an assembled staircase; a first joint part upstanding from a rear portion of the base plate; a second joint part depending from a front portion of the base plate, said upstanding and depending joint parts being arranged to mate with similar joint parts of further units, said upstanding joint part with a depending joint part of an upper further stair unit, and said depending joint part with an upstanding joint part of a lower further stair unit; and a tread part for fixing to an upper surface of the base plate; characterised in that there is defined in a said depending joint part, a hole which is elongate in the depending direction; and in that there is a nut fixedly installed on said upstanding joint part; wherein the depending joint part of one unit is securable to the upstanding joint part of another unit by means of a bolt extending through the elongate hole of the depending part and screwed into a nut of the depending part; and in that the joint parts are of non-circular transverse section, whereby on mating with the joint parts of further units, relative rotation is prevented. The stair unit according to the invention described above may be combined with units selected from second, third, fourth, fifth and sixth types connected to form a staircase, wherein; the second unit type has a base plate which, in the assembled staircase is arranged to extend horizontally, a joint part upstanding from a rear portion of the base plate, a joint part depending from a front portion of the base plate, an upstanding bolt installed centrally in an upper portion of the upstanding joint part, a seating plate which is disposed in the depending joint part, said upstanding joint part and said depending joint part being arranged to mate with similar joint parts of a further unit, said upstanding joint part with a depending joint part of an upper further stair unit, and said depending joint part with an upstanding joint part of a lower further stair unit, such that when in mating relation, relative rotation of the joint parts is possible, the fixing bolt extending through the through hole of a seating plate of a further unit, the units being secured in position by means of upper and lower nuts arranged on the upstanding bolt on opposite sides of the seating plate; third unit type has a base plate which, in the assembled staircase is arranged to extend horizontally, a joint part upstanding from a rear portion of the base plate, and a joint part depending from a front portion of the base plate, a hole defined in the upstanding joint part which is elongate in the upstanding direction of the joint part, a seating plate which is disposed in the depending joint part provided with a through hole therein, said upstanding joint part being arranged to mate with a depending joint part of the first unit type, such that relative rotation of the mating joint parts is prevented, and secured by inserting a bolt through the elongate hole and screwing into the nut of the first stair unit type, the depending joint part being arranged to mate with the upstanding joint part of the second unit type such that relative rotation of mating joint parts is possible, the fixing bolt of the second unit type extending through the through hole of the seating plate and, when mating, the depending joint parts and upstanding joint part of the second unit type being secured by tightening upper and lower nuts arranged on the bolt onto opposite faces of the seating plate; the fourth unit type has a base plate which, in an assembled staircase is arranged to extend horizontally, a joint part upstanding from a rear portion of the base plate, and a joint part depending from a front portion of the base plate, an upstanding bolt installed at an upper portion of the upstanding joint part, and a nut fixed in the depending joint part, the upstanding joint part being arranged to mate with a depending joint part of a second unit type, such that when mated, relative rotation is possible, the fixing bolt extending into the seating plate of the second unit type and being secured by tightening upper and lower nuts arranged on the bolt onto opposite faces of the seating plate of the second unit type, the depending joint part being arranged to mate with an upstanding joint part of the first stair unit type such that relative rotation is not possible, and when mated are secured by means of a bolt inserted through the elongate hole of the upstanding joint part and screwed into the nut; the fifth unit type for use as the uppermost step of a staircase, has a base plate which in an assembled staircase is arranged to extend horizontally, a joint part depending from a front portion of the base plate, a nut fixedly installed therein, the depending joint part being arranged to mate with an upstanding joint part of a first stair unit type, such that when mated, relative rotation is not possible, the joint parts being secured by means of a bolt of the first stair unit type inserted through the elongate hole of the upstanding joint part of the first stair unit and screwed into the nut, the base plate being further adapted for fixing to an upper storey of a building; the sixth stair unit type for use at a lowermost position of a staircase, has a base plate which in an assembled staircase is arranged to extend horizontally, having a joint part upstanding from a rear portion thereof and provided with a hole formed therein, elongate in the upstanding direction, said upstanding joint part being arranged to mate with a depending joint part of a first stair unit type such that when mated, relative rotation is not possible, and being secured by insertion of a bolt through the elongate hole into the nut of the depending joint part of the first stair unit type, said base plate being further adapted for fixing to a floor of a lower storey of a building; and, treads are provided for fixing to upper surfaces of respective base plates of each stair unit. The units may be further selected from seventh and eighth unit types wherein: the seventh unit type has a base plate which in the assembled staircase is arranged to extend horizontally, a joint part upstanding from a rear portion of the base plate, and a joint part depending from a front portion of base plate, a casing part mounted for rotation on an upper end of the upstanding joint part having a plate part on the upper surface thereof, provided at its centre with a nut which is fixed thereto, a seating plate fixed within the depending joint part having a through hole therein, the depending joint part being adapted to mate with the upstanding joint part of another unit of the seventh unit type, such that relative rotation is possible, the plate part thereof abutting the seating plate and being connected thereto by means of a bolt screwed through the hole of the seating plate, into the nut of the movable casing part; the eighth unit type has a base plate which in the assembled staircase is arranged to extend horizontally, a joint part upstanding from a rear portion of the base plate, and a joint part depending from a front portion of the base plate, a casing part, mounted for rotation on an upper end of the upstanding joint part having a plate part on the upper surface thereof, and provided at its centre with a nut fixed thereto, a further nut fixed on the depending joint part, the upstanding joint part being adapted to mate with the depending joint part of a unit of the seventh stair unit type such that relative rotation is possible, with the plate part abutting the fixing plate of the seventh type unit, and is connected thereto by means of a bolt screwed through the hole of the seating plate into the nut of the movable casing part, and the depending joint part being adapted to mate with the upstanding joint part of a first stair unit type such that relative rotation is prevented, and secured by inserting a bolt through the elongate hole of the first unit type and screwing into the further nut. Preferred embodiments of the invention provide a takedown staircase with can be optionally installed in various buildings in the form of a spiral staircase or a staircase with a landing because the arrangement angle and height between the upper and lower stair units are adjustable, and a takedown staircase which can be optionally installed in various buildings in the from of a spiral staircase or a staircase with a landing because the arrangement angle and height between the upper and lower stair units are adjustable and which, even after being set up, does not allow shaking to occur in the whole or in the landing parts or in the curved part because rotation between the stair units can be completely held in check. Embodiments of the invention are described below with reference to the accompanying drawings in which: Figure 1 is a plan view of stair unit according to the first formation of the present invention. Figure 2 is a front view of stair unit illustrated in figure 1. Figure 3 is a left side view of stair unit illustrated in figure 1. Figure 4 is a sectional view taken along the line A-A of figure 1. Figure 5 is a plan view of stair unit for top part. Figure 6 is a front view of stair unit illustrated in figure 5. Figure 7 is a right side view of stair unit illustrated in figure 5. Figure 8 is a sectional view taken along the line B-B of figure 5. Figure 9 is a plan view of stair unit for base part Figure 10 is a front view of stair unit illustrated in figure 9. Figure 11 is a sectional view taken along the line B-B of figure 9. Figure 12 is a plan view of angle adjusting stair unit. Figure 13 is a front view of stair unit illustrated in figure 12. Figure 14 is a right side view of stair unit illustrated in figure 12. Figure 15 is a sectional view taken along the line D-D of figure 12. Figure 16 is a front view of staircase built up with a stair unit illustrated in figure 12. Figure 17 is a vertical sectional view of the upper part of staircase illustrated in figure 16. Figure 18 is a vertical sectional view of the middle part of staircase illustrated in figure 16. Figure 19 is a vertical sectional view of the lower part of staircase illustrated in figure 16. Figure 20 is a vertical sectional view of the important part of completed staircase with a tread attached thereto. Figure 21 is a plan view of level adjusting plate used in the staircase shown in figure 20. Figure 22 is a front view of level adjusting plate shown in figure 20. Figure 23 is a plan view of covering body used in the staircase shown in figure 20. Figure 24 is a sectional view taken along the line E-E of figure 23. Figure 25 is a plan view of covering body used in the staircase shown in figure 20. Figure 26 is a front view of covering body illustrated in figure 20. Figure 27 is a vertical sectional view of other standard-type stair unit. Figure 28 is a vertical sectional view of another standard-type stair unit. Figure 29 is a vertical sectional view of another standard-type stair unit. Figure 30 is a vertical sectional view showing that the other angle adjusting stair unit is disassembled. Figure 31 is a vertical sectional view showing that the other angle adjusting stair unit is disassembled. Figure 32 is a vertical sectional view showing that another angle adjusting stair unit is disassembled. Figure 33 is a vertical sectional view showing that the other angle adjusting stair unit is disassembled. Figure 34 is a plan view of stair unit illustrated in figure 33. Figure 35 is vertical sectional view showing that another angle adjusting stair unit is disassembled. Figure 36 is a diagrammatic plan view illustrated the assembled condition of takedown staircase according to the second formation of the present invention. Figure 37 is a diagrammatic left side view of the staircase illustrated in figure 36. Figure 38 is a sectional view taken along the line A-A of the part transferring to the curved part from the straight part surrounded by the circle III shown in figure 36. Figure 39 is a sectional view taken along the line B-B of the curved part surrounded by the circle IV shown in figure 36. Figure 40 is a sectional view taken along the line C-C of the part transferring to the curved part from the curved part surrounded by the circle V shown in figure 36. Figure 41 is a sectional view taken along the line D-D of the straight part surrounded by the circle VI shown in figure 36. Figure 42 is a plan view of the stair unit for changing to the curved part from the straight part of staircase according to said formation. Figure 43 is a rear view of stair unit illustrated in figure 42. Figure 44 is a left side view of the stair unit illustrated in figure 42. Figure 45 is a sectional view taken along the line E-E of figure 42. Figure 46 is a plan view of stair unit for curved part of staircase according to the sceond formation. Figure 47 is a rear view of stair unit shown in figure 46. Figure 48 is a left aide view of stair unit shown in figure 46. Figure 49 is a sectional view taken along the line F-F of figure 46. Figure 50 is a plan view of stair unit for changing to the straight part from the curved part of staircase according to the second formation. Figure 51 is a rear view of stair unit shown in figure 50. Figure 52 is a left side view of stair unit shown in figure 50. Figure 53 is a sectional view taken along the line G-G of figure 50. Figure 54 is a plan view of stair unit for the straight part of staircase according to the second formation. Figure 55 is a rear view of stair unit shown in figure 54. Figure 56 is a left side view of stair unit shown in figure 54. Figure 57 is a sectional view taken along the line H-H of figure 54. Figure 58 is a diagrammatic left side view showing that the takedown staircase is assembled by way of embodiment according to the second formation of the present invention. Figure 59 is a plan view of stair unit for changing to the straight part from the curved part of staircase shown in figure 58. Figure 60 is a rear view of stair unit shown in figure 58. Figure 61 is a left side view of stair unit shown in figure 58. Figure 62 is a sectional view taken along the line I-I of figure 59. Figure 63 is a plan view of stair unit for the curved part of said embodied staircase. Figure 64 is a rear view of stair unit shown in figure 63. Figure 65 is a left side view of stair unit shown in figure 63. Figure 66 is a sectional view taken along the line J-J of figure 63. Figure 67 is a plan view of stair unit for changing to the curved part from the straight part of said embodied staircase. Figure 68 is a rear view of stair unit shown in figure 67. Figure 69 is a left side view of stair unit shown in figure 67. Figure 70 is a sectional view taken along the line K-K of figure 67. Figure 71 is a diagrammatic plan view illustrating that the a takedown staircase in assembled according to the third formation of the present invention. Figure 72 is a diagrammatic left side view of staircase shown in figure 71. Figure 73 is a sectional view taken along the line A-A to the curved part from the straight part surrounded by the circle III shown in figure 71. Figure 74 is a sectional view taken along the line B-B of curved part surrounded by the circle IV shown is figure 71. Figure 75 is a sectional view taken along the line C-C of the part transferring from the curved part surrounded by the circle V shown in figure 71. Figure 76 is a sectional view taken along the line D-D of the straight part surrounded by the circle VI in figure 71. Figure 77 is a plan view of stair unit for changing to the curved part from the straight part of staircase according to the third formation. Figure 78 is a rear view of stair unit shown in figure 77. Figure 79 is a left side view of stair unit shown in figure 77. Figure 80 is a sectional view taken along the line E-E of figure 77. Figure 81 is a plan view of stair unit for the curved part of said staircase. Figure 82 is a rear view of stair unit shown in figure 81. Figure 83 is a left side view of stair unit shown in figure 81. Figure 84 is a sectional view taken along the line F-F of figure 81. Figure 85 is a plan view of stair unit for changing to the straight part from the curved part of staircase according to the third formation. Figure 86 is a rear view of stair unit shown in figure 85. Figure 87 is a left side view of stair unit shown in figure 85. Figure 88 is a sectional view taken along the line G-G of figure 85. Figure 89 is a plan view of stair unit for the straight part of staircase according to the third formation. Figure 90 is a rear view of stair unit shown in figure 89. Figure 91 is a left side view of stair unit shown in figure 89. Figure 92 is a sectional view taken along the line H-H of figure 89. Figure 93 is a diagrammatic left side view showing that the takedown staircase is assembled according to the third formation of the present invention. Figure 94 is a plan view of stair unit for changing from the curved part to the straight part of staircase shown in figure 93. Figure 95 is a rear view of stair unit shown in figure 93. Figure 96 is a left side view of stair unit shown in figure 93. Figure 97 is a sectional view taken along the line I-I of figure 94. Figure 98 is a front view of stair unit for the curved part of staircase according to the third formation. Figure 99 is a rear view of stair unit shown in figure 98. Figure 100 is a left side view of stair unit shown in figure 98. Figure 101 is a sectional view taken along the line J-J of figure 98. Figure 102 is a front view of stair unit for changing to the curved part from the straight part of staircase according to the third formation. Figure 103 is a rear view of stair unit shown in figure 102. Figure 104 is a left side view of stair unit shown in figure 102. Figure 105 is a sectional view taken along the line K-K of figure 102. The present invention will now be described according to the drawings attached hereto. An explanation of the first formation will be given hereinafter. It comprises an upstanding joint part 2 referred to as an upward joint 2 and a depending going part 3 referred to as a downward joint 3 vertically installed at the base end and front end of horizontal base plate 1, a stair unit 4 which is connected to further units forming upper and lower steps by mating the upward joint 2 and the downward joint 3 with other similar joint parts of other units and securing the mating joint parts by inserting a bolt through an elongate longitudinal hole 5 bored in the upward joint 2 or in the downward joint 3, and screwing into a nut 6 fixed on the mating joint part a tread 8 which is fixed to the upper surface of horizontal base plate, the transverse sections of upward joint 2 and downward joint 3 being non-circular so that the mating joint parts may not be rotated relative to each other. In the stair units 4A or in the stair units 4B (forming the subject of claims 3 and 4), one side of upward joint 2 and one side of downward joint 3 are formed by being separated from the horizontal base plate 1, and a fixing plate 9 is fixed to the separately formed upward joint 2 or downward joint 3 and, in the fixing plate, a hole 10 is made on the longitudinal central -line of separately formed upward joint 2 or downward joint 3, and a bolt 11 is vertically fixed to the horizontal base plate 1, and the separately formed upward joint 2 or downward joint 3 is fixed to the horizontal base plate 1 by spirally uniting the nut 12 with the bolt 11 inserted through the hole 10. In the staireunits 4C or in the stair units 4D (forming the subject of claims 5 and 6), one side of upward joint 2 and one side of downward joint 3 are formed by being separated from the horizontal base plate 1, and a fixing plate 13 is fixed to the separately formed upward joint 2 or downward joint 3, and a bolt 15 is inserted through the hole 14 of fixing plate installed on the longitudinal central line of separately formed upward joint 2 or downward joint 3, and the separately formed upward joint 2 or downward joint 3 is fixed to the horizontal base plate 1 by spirally inserting the bolt 15 into the nut 16 fixedly provided in the horizontal base plate 1. In the stair units 4E or in all the stair units 4F for (forming the subject of claims 7 and 8), one side of upward joint 2 and one side of downward joint 3 are formed by being separated from the horizontal base plate 1, and an installing plate 17 is provided in the separately formed upward joint 2 or downward joint 3, and the separately formed upward joint 2 or downward joint 3 is fixed to the horizontal base plate 1 by spirally inserting a tapping vis 19 into the receiving hole 20 provided in the horizontal base plate 1 from the through hole 18 made in the installing plate 17. An explanation of the second formation according to the present invention will be given hereinbelow. It comprises ; a stair unit 107 in which an upward joint 102 and a downward joint 103 are projectingly installed at the base end and front end of horizontal base plate 101, and a longitudinal long hole 104 is made in the upward joint 102, and a nut 105 is provided in the upward joint 103, and the upward and downward joint 102, 103 of upper and lower flights which are inserted/united unrotatably are fixed by a bolt 106 spirally inserted into the nut 105 from the longitudinal long hole 104, a stair unit 114 in which an upward joint 108 and a downward joint 109 are vertically installed at the base end and front end of horizontal base plate 101, and a fixing bolt 110 is vertically installed in the,upper central part of upward joint 108, and a horizontal seating plate 111 is fixed within the downward joint 109, and the upward joint and downward joints 108, 109 of upper and lower flights which are inserted/united rotatably are fixed by holding the horizontal seating plate 111 between the upper nut 112 and the lower nut 113 which are spirally united with the fixing bolt 110, a stair unit 115 in which an upward joint 102 and a downward joint 109 are vertically installed at the base end and front end of horizontal base plate 101, and a longitudinal long hole 104 is made in the upward joint 102, and a horizontal seating plate 111 is fixedly installed within the downward joint 109, and the upward joint 102 is fixed by being unrotatably set in the downward joint 103 of stair unit 107 and by the bolt 106 spirally inserted into the nut 105 from the longitudinal long hole 104 and the downward joint 109 is fixed by being rotatably set in the upward joint 108 of stair unit 114 and by holding the horizontal seating plate 111 between the upper and lower nuts 112,113 which are spirally united with the fixing bolt 110. a stair unit 116 in which an upward joint 108 and a downward joint 103 are vertically installed at the base end and front end of horizontal base plate 101, and a fixing bolt 110 is vertically installed in the upper central part of upward joint 108, and a nut 105 is provided in the downward joint 103, and the upward joint 108 is fixed by being rotatably set in the downward joint 109 and by holding the horizontal seating plate 111 between the upper and lower nuts 112,113 which are spirally united with the fixing bolt 110 and the downward joint 103 is fixed by being unrotatably set in the upward joint 102 of stair unit 107 and by the bolt 106 spirally inserted into the nut 105 from the longitudinal long hole 104. a stair unit 117 for top part in which a downward joint 103 is vertically installed at the front end of horizontal base plate 101, and a nut 103 is fixedly installed in the downward joint 103, and the downward joint 103 which is set unrotatably in the upward joint 102 of stair unit 107 is fixed by the bolt 106 spirally into the nut 105 from the longitudinal long hole 104 and the horizontal base plate 101 is fixed to the floor of the upper storey, a stair unit for base part 118 in which an upward joint 102 is vertically installed in the horizontal base plate 101, and a longitudinal long hole 104 is made in the upward joint 102, and the upward joint 102 which is unrotatably set in the downward joint 103 of stair unit 107 is fixed by the bolt 106 which is spirally inserted into the nut 105 from the hole 104 and the horizontal base plate 101 is fixed to the floor of the lower storey, and a tread 119 which is fixed to the upper side of horizontal base plate 101 in each stair unit. An explanation of the third formation according to the present invention will now be given. It comprises ; a stair unit 207 in which an upward joint 202 and a downward joint 203 are vertically installed at the base end and front end of horizontal base plate 201, and a longitudinal long hole 204 is made in the upward joint 202, and a nut 205 is fixedly installed in the downward joint 203, and the upward and downward joints 202, 203 of upper and lower flights are fixed by the bolt 206 spirally inserted into the nut 205 from the longitudinal long hole 204, a stair unit 214 in which an upward joint 208 and a downward joint 209 are vertically installed at the base end and front end of horizontal base plate 201, and a movable case 210 is vertically spirally connected with the upper end of upward joint 208, and a nut 213 is fixedly installed in the central part of the horizontal plate part 226 of movable case 210, and a horizontal seating plate 211 is fixedly installed within the downward joint 209, and the upward and downward joints 208, 209 of upper and lower flights which are rotatably set in are fixed by pressing the horizontal plate part 226 to the horizontal seating plate 211 with a bolt spirally united with the nut 213, a stair unit 215 in which an upward joint 202 and a downward joint 209 are vertically installed at the base end and front end of horizontal base plate 201, and a longitudinal long hole 204 is made in the upward joint 202, and a horizontal seating plate 211 is fixedly installed within the downward joint 209, and the upward joint 202 is fixed by being unrotatably set in the downward joint 203 of stair unit 207 and by a bolt 206 spirally united with the nut 205 from the longitudinal long hole 204, and the downward joint 209 is fixed by being rotatably set in the upward joint 208 of stair unit 214 and by fastening the horizontal plate part 226 to the horizontal seating plate with a bolt 212 spirally united with the nut 213, a stair unit 216 in which an upward joint 208 and a downward joint 203 are vertically installed at the base end and front end of horizontal base plate 201, and a movable case 210 is vertically connected with the upper end of upward joint 208, and a nut 213 is fixedly provided in the central part of the horizontal plate part 226 of movable case 210, and a nut 205 is fixedly provided in the downward joint 203, and the upward joint 208 is fixed by being rotatably set in the downward joint 209 of stair unit 214 and by fastening the horizontal plate part 226 to the horizontal seating plate 211 with a bolt spirally united with the nut 213 and the downward joint 203 is fixed by being unrotatably set in the upward joint 202 of stair unit 207 and by a bolt 206 spirally inserted into the nut 205 from the longitudinal long hole 204, a top stair unit 217 in which a downward joint 203 is vertically installed at the front end of horizontal base plate 201, and a nut 205 is fixedly provided in the downward joint 203, and the downward joint 203 which is unrotatably set in the upward joint 202 of stair unit 207 is fixed by a bolt 216 spirally inserted into the nut 205 and the horizontal base plate 201 is fixed to the floor of upper storey, a base stair unit 218 in which an upward joint 202 is vertically installed in the horizontal base plate 201, and a longitudinal long hole 204 is bored in the upward joint 202, and the upward joint 202 which is unrotatably set in the downward joint 203 of stair unit 207 is fixed by a bolt 206 spirally inserted into the nut 205 from the penetrating hole 204 and the horizontal base plate 201 is fixed to the floor of lower storey and, a tread 219 which is fixed to the upper side of horizontal base plate 201 in each stair unit. The process of the first formation according to the present invention will be described hereinafter. The takedown staircase according to the present invention can be fixed up to the upper floor from the lower floor or to the lower floor from the upper floor. To fix it up from the lower floor, for example, a base stair unit 4G is fixed to the lower floor 24 as illustrated in Figure 16. This base stair unit 4G is devoid of downward joint 3 from the standard stair unit 4. The horizontal base plate 4 is fixed directly to the floor 24 by a vis 25. As illustrated in Figure 19, the downward joint 3 of stair unit 4 on the first step is inserted into the upward joint 2 of base stair unit 4G and the upward joint 2 is fixed to the downward joint 3 by a bolt 7. The bolt 7 and a bolt driving tool are inserted from the upper open parts of upward joint 2 and downward joint 3. Then, as illustrated in Figure 18, the downward joint 3 of stair unit 4 on the second step is inserted into the upward joint 2 of stair unit 4 on the first step and the upward joint 2 is fixed to the downward joint 3 by the same bolt 7. After stair units are fixed up in consecutive order up to the stair unit 4 on the second flight from the top, the downward joint 3 of top stair unit 4H is inserted into the upward joint 2 of stair unit 4 on the second flight from the top and the upward joint 2 is fixed to the downward joint 3 by the said bolt 7, as illustrated in Figure 16 and Figure 17. This top stair unit 4H is devoid of upward joint 2 from the standard stair unit 4. At the base end of horizontal base plate 1, instead of upward joint 2, a bracket plate 27 for the upper floor or a landing is fixedly installed. The bracket plate 27 will be fixed to the floor 26 by a bolt or a vis 28. The height between the upper stair unit 4 and the lower stair unit is adjustable by means of free length between the longitudinal long hole 5 and the bolt 7 for every step or several steps or for a particular step. In this manner, a straight stairacse will be fixed up by arranging the upper stair unit 4 and the lower stair unit 4 from the lower storey to the upper storey. As illustrated in Figures 17 to 20, a one side-toothed or a both sides -toothed washer 21 is inserted between the head of bolt 7 and the upward joint 2 or the downward joint 3 and this washer 21 is pressed by tightening the bolt 7. The upward joint 2 and the downward joint 3 are tightly united by the washer 21 sticking to its contact surface and a stair unit is not caused to sink down by the loosening of bolt 7. As it is necessary to change or adjust the angle of arrangement between the upper and lower units in the landing part or in the curved part when a staircase provided with a landing or a geometrical staircase or a spiral staircase is fixed up, an angle adjustment-type stair unit 4A,4B,4C,4D, 4E or 4F is used in which the upward joint 2 or the downward joint 3 is fixed to the horizontal base plate 1 after it is turned on the longitudinal axis. Although the standard-type stair unit 4 in which the upward joint 2 and the downward joint 3 are installed in the horizontal base plate 1 from the beginning is generally used to fix up the straight part other than a landing part or a bending part, the stright part can be fixed up with those stair units 4A to 4F. The whole body of such a straight staircase can also be fixed up with those angle adjustment-type stair units 4A to 4F. For any part, whether it is landing part, bending part or straight part, the angle adjustment-type stair units 4A to 4F and the standard-type stair unit 4 can be used by combining one or several of them. In case the angle adjustment-type stair unit 4A separated from the upward joint 2 is used as illustrated in Figure 12 to 15, the separated upward joint 2 is fixed to the horizontal base plate 1 by inserting the downward joint 3 of stair unit 4 into the upward joint 2 of lower stair unit 4 or into the upward joint 2 of base stair unit 4D and fastening the said upward joint 2 and the downward joint 3 with a bolt 7 and then turning the upward joint 2 to the required angle on the fixing bolt 11 for the horizontal base plate 1 fixed to the stair unit 4A and tightening a nut 12 as illustrated in Figure 18 and Figure 19. Between the fixing plate 9 and the horizontal base plate 1 or between the nut 12 and the fixing plate 9 a one side-toothed or a both sides-toothed or a both sides-toothed washer 22 is interposed and strongly pressed by tightening the nut 12. The upward joint 3 is thereby connected so tightly as not to be rotatable with the horizontal base plate 1. Thus, the stair unit 4A will never move round or rattle. Into the tightly positioned upward joint 2, the downward joint 3 of next angle adjustment-type stair unit 4A or standard-type stair unit 4 is inserted and fixed thereto by tightening a bolt 7. In case another angle adjustment-type stair unit 4B separated from the downward joint 3 as illustrated in Figure 30 is used, the upward joint 2 of stair unit 4B is inserted into the downward joint 3 of upper stair unit 4 or into the dounward joint 3 of top stair unit 4H and the downward joint 3 is fixed to the upward joint 2 by tightening a bolt 7. Then, the downward joint 3 is fixed to the horizontal base plate 1 by being turned to the required angle on the fixing bolt 11 for the tightly positioned horizontal base plate 1 of stair unit 4B and by tightening a nut 12. Between the fixing plate 9 and the horizontal base plate 1 or between the nut 12 and the fixing plate 9 a one side-toothed or a both sides-toothed washer 22 is interposed and strongly pressed by tightening the nut 12. The upward joint 2 is thereby connected so tightly as not to be rotatable with the horizontal base plate 1. So, the stair unit 4A will never rattle by the loosening of nut 12. Into the tightly positioned downward joint 3, the upward joint 2 of next angle adjustment-type stair unit 4B or standard-type stair unit 4 is inserted and fixed thereto by tightening a bolt 7. In case another angle adjustment-type stair unit 4C separated from the upward joint 2 as illustrated in Figure 31 is used, the downward joint 3 of stair unit 4C is inserted into the upward joint 2 of lower standard-type stair unit 4 or into the upward joint 2 of base stair unit 4G and the upward joint 2 is fixed to the downward joint 3 by tightening a bolt 7, Then, the upward joint 2 is fixed to the horizontal base plate 1 by being turned to the required angle on the bolt 15 inserted into a nut 16 for the horizontal base plate of stair unit 4C and by tightening a bolt 15. Between the fixing plate 13 and the horizontal base plate 1 or between the bolt 15 and the fixing plate 13 a one side-toothed or a both sides-toothed washer 23 is interposed and strongly pressed by tightening the bolt 15. The upward joint 2 is thereby connected so tightly as not to be rotatable with the horizontal base plate 1. Thus, the stair unit 4A will never move round or rattle by the loosening of bolt 15. Into this tightly positioned upward joint 2, the downward joint 3 of next angle adjustment-type stair unit 4C or standard-type stair unit 4 is inserted and fixed thereto by tightening a bolt 7. In case another angle adjustment-type stair unit 4D separated from the downward joint 3 as illustrated in Figure 32 is used, the upward joint 2 of stair unit 4D is inserted into the downward joint 3 of upper standard-type stair unit 4 or into the downward joint 3 of base stair unit 4H and the downward joint 3 is fixed to ther upward joint 2 by tightening a bolt 7. Then, the downward joint 3 is fixed to the horizontal base plate 1 by being turned to the required angle on the bolts 15 inserted into the nut 16 for the horizontal base plate 1 of stair unit 4D and by tightening a bolt 15. Between the fixing plate 13 and the horizontal base plate 1 or between the bolt 15 and the fixing plate 13 a one side-toothed or a both sides-toothed washer 23 is insterposed and strongly pressed by tightening the bolt 15. The upward joint 2 is thereby connected so tightly as not to be rotatable with the horizontal base plate 1. Thus, the stair unit 4A will never move round or rattle by the loosening of bolt 15. Into this tightly positioned downward joint 3, the upward joint 2 of next angle adjustment-type stair unit 4D or standard-type stair unit 4 is inserted and fixed thereto by tightening a bolt 7. In case another angle adjustment-type stair unit 4E separated from the upward joint 2 as illustrated in Figure 33 is used, the downward joint 3 of stair unit 4E is inserted into the upward joint 2 of lower standard-type stair unit 4 or into the upward joint 2 of base stair unit 4G and the upward joint 2 is fixed to the downward joint 3 by tightening a bolt 7. Then, the upward joint 2 is turned to the required angle for the horizontal base plate 1 of stair unit 4E. As illustrated in Figure 34, a receiving hole 20 which corresponds with the penetrating hole 18 of installing plate 17 is bored with a drill under the condition that the upward joint 2 is kept at its position and a tapping vis 19 is spirally inserted into the receiving hole 20 from the penetrating hole 18 and the upward joint 2 is thereby fixed to the horizontal base plate 1. Into this tightly positioned upward joint 2 the downward joint 3 of next angle adjustment-type stair unit 4E or standard-type stair unit 4 is inserted and fixed thereto by tightening a bolt 7. In case another angle adjustment-type stair unit 4F separated from the downward joint 3 as illustrated in Figure 35 is used, the upward joint 2 of stair unit 4F is inserted into the downward joint 3 of upper standard-type stair unit 4 or into the downward joint 3 of top stair unit 4H and the downward joint 3 is fixed to the upward joint by tightening a bolt 7. Then, the downward joint 3 is turned to the required angle for the horizontal base plate 1 of stair unit 4F. After a receiving hole 20 which corresponds with the penetrating hole 18 of installing plate 17 is bored in the horizontal base plate 1 with a drill under the condition that the downward joint 3 is kept at its position, and a tapping via 19 is spirally inserted into the receiving hole 20 from the penetrating hole 18 and the downward joint 3 is thereby fixed to the horizontal base plate 1. Into this tightly positioned downward joint 3, the upward joint 2 of next angle adjustment-type stair unit 4F or standard-type stair unit 4 is inserted and fixed thereto by tightening a bolt 7. Then, an explanation of the process of the second formation according to the present invention will be given. The takedown staircase according to the present invention can be fixed up to the upper floor from the lower floor or to the lower floor from the upper floor. To fix it up from the lower floor, for example, the horizontal base plate 101 of base stair unit 118 is fixed to the lower floor 120 with a vis 121, as illustrated in Figure 37. When a straight part connected between the upper floor and the lower floor is fixed up by means of stair unit 107, a curved part like a landing is fixed up by means of stair unit 114, as illustrated in Figure 36, the downward joint 103 of the first stair unit 107 for straight part is inserted into the upward joint 102 of base stair unit 118 and the upward joint 102 is fixed to the downward joint 103 by tightening, a bolt 106. The bolt 106 and a driving tool are inserted from the upper opened part of upper joint 102 and downward joint 103, as illustrated in Figure 37. Next, the downward joint 103 of the second stair unit 107 is inserted into the upward joint 102 of the first stair unit 107 and the upward joint 102 is fixed to the downward joint 103 by tightening a bolt 106, as illustrated in Figure 41. In this way, the downward joint 103 of upper stair unit 107 is united with the upward joint 102 of lower stair unit 107 and the upward joint 102 is fixed to the downward joint 103 by tightening a bolt 106 and the straight part on the part of lower floor is thereby fixed upward in consecutive order. Into the upward joint 102 of topmost stair unit 107 in the said straight part, the downward joint 103 of stair unit 116 used for turning to the curved part from the straight part is inserted and fixed thereto by tightening a bolt 106, as illustrated in Figure 40. Into the upward joint 108 of said stair unit 116, the downward joint 109 of stair unit 114 used for the curved part is inserted and fixed thereto by tightening an upper nut 112 and a lower nut 113. As illustrated in Figure 39, the downward joint 109 of upper stair unit 114 is inserted into the upward joint 108 of lower stair unit 114 and the upward joint 108 is fixed to the downward joint 109 by tightening the upper nut 112 and the lower nut 113 and the curved part is thereby fixed upward in consecutive order. Into the upward joint 108 of topmost stair unit 114 in the curved part, the downward joint 109 of stair unit 115 used for turning to the straight part from the curved part is inserted and fixed thereto by tightening the upper nut 112 and the lower nut 113, as illustrated in Figure 38. Into the upward joint 102 of said stair unit 115, the downward joint 103 of stair unit 107 used for the straight part is inserted and fixed thereto by tightening a bolt 106. As illustrated in Figure 41, the downward joint 103 of upper stair unit 107 is inserted into the upward joint 102 of lower stair unit 107 and the upward joint 102 is fixed to the downward joint 103 by tightening a bolt 106. Thus, the upper and lower straight parts are thereby fixed upward in consecutive order. Into the upward joint 102 of topmost stair unit 107 in the straight part for the upper storey, the downward joint 103 of top stair unit 117 is inserted and these two joints 102,103 are fixed by tightening a bolt 106. Lastly, the installing plate 122 fixed at the base end of horizontal base plate 101 of top stair unit 117 is fixed to the floor of upper storey by a vis 123. As the upward and downward joints 102,103 of upper and lower stair units 107,107 are inserted/united unrotatably in the straight part for the upper storey and in the straight part for the lower storey, the arrangement angle in the horizontal plane between the upper and lower stair units 107, 107 cannot be changed. As the upward joint 102 and the downward joint 103 are inserted/united unrotatably even between the stair unit for base part 118 and the stair unit for straight part 107, the arrangement angle of both stair units cannot be changed. As the downward joint 103 and the upward joint 102 are inserted/united unrotatably even between the stair unit for top part 117 and the stair unit for straight part 107, the arrangement angle of both stair units cannot be changed. As the upward joint 102 and the downward joint 103 are inserted/united unrotatably even between the stair unit for straight part 107 and the stair unit for changing part 116, the arrangement angle of both stair units cannot be changed. As the upward joint 102 and the downward joint 103 are inserted/united unrotatably even between the stair unit for straight part 107,107, the arragement angle of both stair units cannot be changed. In the curved part, however, the upward and downward joints 108,109 of upper and lower stair units 114,114 are rotatably inserted/united. So, the arragement angle in the horizontal plane between the upper and lower stair units 114, 114 is changeable consecutively. As the upward joint 108 and the downward joint 109 are rotatably inserted/united even between the stair unit for changing part 116 and the stair unit for curved part 114, the arrangement angle of both stair units is changeable. As the upward joint 108 and the downward joint 109 are inserted/united rotatably even between the stair unit for curved part 114 and the stair unit for changing part 115, the arrangement angle of both stair units is changeable consecutively. The height between the stair unit for base part 118 and the stair unit for straight part 107 is adjustable by means of free length between the longitudinal long hole 104 and the bolt 106. The height between the upper and lower stair units 107, 107 in the straight part for the lower storey is adjustable for every step or several steps or for a particular step by means of free length between the longitudinal long hole 104 and the bolt 106. The height between the stair unit for straight part 107 and the stair unit for changing part 116 is adjustable by means of free length between the longitudinal long hole 104 and the bolt 106. The height between the stair unit for changing part 116 and the stair unit for curved part 114 is adjustable by moving up and down the spirally uniting position of upper nut 112 and lower nut 113 with the fixing bolt 110. The height between the upper and lower stair units 114,114 is adjustable for every step or several steps or for a particular step by moving up and down the spirally uniting position of upper nut 112 and lower nut 113 with the fixing bolt 110. The height between the stair unit for curved part 114 and the stair unit for changing part 116 is adjustable by moving up and down the spirally uniting position of upper nut 112 and lower nut 113 with the fixing bolt 110. The height between the stair unit for changing part 115 and the stair unit for straight part 107 is adjustable by means of free length between the longitudinal long hole 104 and the bolt 106. The height between the upper and lower stair units 107,107 in the straight part for the upper storey is adjustable for every step or several steps or for a particular step by means of free length between the longitudinal long hole 104 and the bolt 106. The height between the stair unit for straight part 107 and the stair unit for top part 117 is adjustable by means of free length between the horizontal long hole 104 and the bolt 106. In this way, a straight staircase provided with a landing or a curved staircase which has a curved part or is curved in its main part is built by properly fixing up a stair unit 107 for straight part, a stair unit 114 for curved part, a stair unit 115 for changing part and a stair unit 116 for changing part and using them together with a stair unit 117 for top part and a stair unit 118 for base part. To the horizontal base plate 101 of each stair unit a tread 119 is fixed. Next, the process of the third formation according to the present invention will be described. The takedown staircase according to the present invention can be fixed up to the upper storey from the lower storey or to the lower storey from the upper storey. In case it is fixed up from the lower floor to the upper floor, for example, the horizontal base plate 201 of stair unit 218 for base part is fixed to the lower floor by tightening a vis 221, as illustrated in Figure 72. When the straight part between the upper and lower floors is formed of a stair unit 207 and the curved part like a landing part is formed of a stair unit 214 as illustrated in Figure 71, the downward joint 203 of the first stair unit 207 for straight part is inserted/united with the upward joint 202 of stair unit 218 for base part and the upward joint 202 is fixed to the downward joint 203 by tightening a bolt 206, as illustrated in Figure 72. The bolt 206 and a driving tool are inserted from the upper open parts of upward joint 202 and downward joint 203. Next, as illustrated in Figure 76, the downward joint 203 of the second stair unit 207 is inserted/united with the upward joint 202 of the first stair unit 207 and the upward joint 202 is fixed to the downward joint 203 by tightening a bolt 206. In this way, the straight part for the lower storey is fixed up in consecutive order by uniting the downward joint 203 of upper stair unit 207 with the upward joint 202 of lower stair unit 207 and by fixing the upward joint 202 to the downward joint 203 with a bolt 206. Into the upward joint 202 of topmost stair unit 207 in the said straight part, the downward joint 203 of stair unit 216 for changing from the straight part to the curved part is inserted and fixed thereto by tightening a bolt 206, as illustrated in Figure 75. Into the upward joint 208 of said stair unit 216, the downward joint 209 of stair unit 214 for curved part is inserted and fixed thereto by a bolt 212 and a nut 213. As illustrated in Figure 74, the curved part is fixed up in consecutive order by uniting the downward joint 209 of upper stair unit 214 with the upward joint 208 of lower stair unit 214 and by fixing the upward joint 208 to the downward joint 209 with a bolt 209 and a nut 213. Into the upward joint 208 of topmost stair unit 214 in the said curved part, the downward joint 209 of stair unit 215 for changing from the curved part to the straight part is inserted and fixed thereto by a bolt 212 and a nut 213, as illustrated in Figure 73. Into the upward joint 202 of said stair unit 215, the downward joint 203 of stair unit 207 for straight part is inserted and fixed thereto by a bolt 206. As illustrated in Figure 76, the straight part for the upper floor is fixed up in consecutive order by uniting the downward joint 203 of upper stair unit 207 with the upward joint 203 of upper stair unit 207 with the upward joint 202 of lower stair unit 207 and by fixing the upward joint 202 to the downward joint 203 with a bolt 206. Into the upward joint 202 of topmost stair unit 207 in the straight part for the upper floor, the downward joint 203 of stair unit 217 for top part is inserted and the upward joint 202 is fixed to the downward joint 203 by tightening a bolt 206. Lastly, the installing plate 222 fixed to the base end of the horizontal base plate 201 of stair unit 217 for top part is fixed to the floor of upper storey by a vis 223. In the straight part for the upper storey and in the straight part for the lower storey, the upward and downward joints 202,203 of the upper and lower storeys 207,207 are inserted/united unrotatably. So, the arrangement angle in the horizontal plane between the upper and lower stair units 207, 207 is unchangeable. As the upward joint 202 and the downward joint 203 are inserted/united unrotatably even between the stair unit 218 for base part and the stair unit 207 for straight part, the arrngement angle of both stair units is unchangeable. As the downward joint 203 and the upward joint 202 are also inserted/united unrotatably between the stair unit 217 for top part and the stair unit 207 for straight part, the arrangement angle of both stair units is unchangeable. As the upward joint 202 and the downward joint 203 are also inserted/united unrotatably between the stair unit 207 for straight part and the stair unit 216 for changing part, the arrangement angle of both stair units is unchangeable. As the upward joint 202 and the downward joint 203 are also inserted/ united unrotatably between the stair unit 215 changing part and the stair unit 207 for straight part, the arrangement angle of both stair units is unchangeable. In the curved part, the upward and downward joint 208, 209 of upper and lower stair units 214,214 are inserted/united rotatably. So, the upper and lower stair units 214, 214 can change the arrangement angle consecutively in the horizontal plane. As the upward joint 208 and the downward joint 209 are also inserted/united rotatably between the stair unit 216 for changing part and the stair unit 214 for curved part, the arrangement angle of both stair units is changeable consecutively. As the upward joint 208 and the downward joint 209 between the stair unit 214 for curved part and the stair unit 215 for changing part are also inserted/united rotatably, the arrangement angle of both stair units is changeable consecutively. The height between the stair unit 218 for base part and the stair unit 207 for straight part is adjustable by means of free length between the longitudinal long hole 204 and the bolt 216. The height between the upper and lower stair units 207, 207 in the straight part for the lower storey is adjustable for every step or several steps or for a particular step by means of free length between the longitudinal long hole 204 and the bolt 206. The height between the stair unit 207 for straight part and the stair unit 216 for changing part is adjustable by means of free length between the longitudinal long hole 204 and the bolt 206. The height between the stair unit 216 for changing part and the stair unit 214 for curved part is adjustable by moving up and down the spirally uniting position of movable case 210 with the upward joint 208. The height between the upper and lower stair units 214, 214 in the curved part is adjustable for every step or several steps or for a particular step by moving up and down the spirally uniting position of movable case 210 with the upward joint 208. The height between the stair unit 214 for curved part and the stair unit 215 for changing part is adjustable by moving up and down the spirally uniting position of movable case 210 with the upward joint 208. The height between the stair unit 215 for changing part and the stair unit 207 for straight part is adjustable by means of free length between the longitudinal long hole 204 and the bolt 206. The height between the upper and lower stair units 207, 207 in the straight part for the upper storey is adjustable for every step or several steps or for a particular step by means of free length between the longitudinal long hole 204 and the bolt 206. The height between the stair unit 207 for straight part and the stair unit 217 for top part is adjustable by means of free length between the longitudinal long hole 204 and the bolt 206. In this way, a straight stair case provided with a landing or a curved staircase which has a curved part or is curved consecutively in its main part is built by properly fixing up a stair unit 207 for straight part, a stair unit 14 for curved part, a stair unit 215 for changing part and a stair unit 216 for changing part and using them together with a stair unit 217 for top part and a stair unit 218 for base part. To the horizontal base plate 201 of each stair unit a tread 219 is fixed. An embodiment of the first formation according to the present invention will be described hereinafter. In the standard stair unit 4 as illustrated in Figures 1 to 4, its upward joint 2 and its downward joint 3 are formed of a quadrilaterally grooved body manufactured by bending and processing a metallic plate. These joints ard lightweight due to an open part in its side. A lateral hole 29 which communicates with a long hole 5 and a nut 6 in the three sides of upward joint 2 is bored before bending said metallic plate. The nut 6 is welded to the outer surface of said downward joint 3. In order to insert the upward joint 2 into the downward joint 3 as tightly as possible, the inner measurements of downward joint 3 is made as approximate as possible to the outer measurements of upward joint 2. The upward joint 2 is welded to the horizontal base plate 1 by inserting its lower end into the angular hole 30 bored at the base end of horizontal base plate 1. The downward joint 3 is welded to the horizontal base plate 1 by inserting its upper end into another angular hole 31 bored at the front end of horizontal base plate 1. A reinforcing plate 32 which is bent and processed like an angular groove is welded to the side of projecting part at the lower end of upward joint 2 and to the side of the upper end of downward joint 3 and said reinforcing plate 32 is welded to the lower face of horizontal base plate 1. Between the downward joint 3 and the horizontal base plate 1, two triangular reinforcing plates 33 are welded symmetrically. The horizontal base plate 1, the upward joint 2 and the downward joint 3 which are connected with each other in such a manner as described above form a framework of stair unit 4. However, in order to improve its external appearance when installed in a building, the framework is covered with a plastic-molded dressing cover 34 as shown in Figure 23 and Figure 24. The cover 34 is fixed to the horizontal base plate 1 by spirally inserting a tapping vis 36 into the vis -receiving case 37 in the inner wall of cover from the six longitudinal holes 35 bored in the outer edge of horizontal base plate 1 before a staircase is fixed up, as illustrated in Figure 20. The case 30 which receives a tread-fixing via 40 is installed in the bottom of cover 34. As illustrated in Figure 20, the tread 8 is fixed to the upper side of horizontal base plate 1 by spirally inserting a vis 40 into the four spiral holes 39 bored in the outer edge of horizontal base plate 1 and, in order to install the tread 8 correctly at the horizontal position, a level adjsuting plate 41 is inserted between the tread 8 and the horizontal base plate 1 as shown in Figure 20. This level adjusting plate 41 has such nuts 42 as welded to the under surface of its own edge, as show in Figure 21 and Figure 22, and the front end of the vis 43 spirally inserted into the nut comes into contact with the upper surface of horizontal base plate 1. The level adjusting plate 41 can be installed horizontally by increasing or decreasing the depth of spirally inserting the four vises 43 and the tread 8 which comes into contact with the upper surface thereof can also be installed horizontally. In the base end of this level adjusting plate 41, a circular hole 44 into which the upward joint 2 will be freely inserted is bored. In the front end of this level adjusting plate 41, a hole 45 through which a tread-fixing vis 40 will pass is bored. The downward edge 46 formed in the outer circumference of this level adjusting plate 41 will be united with the upper end of cover 34. When the height between the upper and lower units 4,4 is adjusted, an opening is made between the lower end of cover 34 and the upper surface of level adjusting plate 41 and the base end of upward joint 2 is exposed. In order to avoid such an unsightly appearance, a plastic cover case 47 of the same color as the cover 34 is prepared. This cover case 47 is formed like a cylinder, as illustrated in Figure 25 and Figure 26. The cover case 47 is inserted into the lower cylindrical part 48 of cover when the upward and downward joints 2,3 of upper and lower stair units are inserted/united. In the inner surface of lower cylindrical part 48, a circular concave part 49 is formed and the cover case 47 is kept still by bringing its upper inserting end into elastic contact with the circular concave part 49. In order to positively check the rotation of cover case 47, the upper jaw 50 at the lower end of cover case 47 must be fixed to the level adjsuting plate 41. As the basic formation of other standard stair unit 4 and angle-adjusting stair units 4A to 4F which will be described hereinafter is the same as the beforesaid standard stair unit excepting for structure in which the separately formed upward joint 2 or downward joint 3 is connected to the horizontal base plate 1, a detailed description thereof will not be made and only different points will be explained hereinbelow. The stair unit 4H for base part as illustrated in Figure 5 to 8 is formed like a standard stair unit with its base end being cut off. In the bracket plate 27 vertically welded to the horizontal base plate 1, a vis-inserting hole 51 is bored in three places. Between the lower end of bracket plate 27 and the downward joint 3, a reinforcing plate 32 is welded. In the stair unit 4G for base part, as illustrated in Figures 9 to 11, vis-inserting holes 52 are bored in its horizontal base plate 1 and these holes 52 are formed like long holes to make it possible to adjust installing positions. In the lower ends of angularly grooved upward joint 2, four reinforcing plates 53 are welded to its ridgeline. In the angle-adjusting stair unit 4A as illustrated in Figures 12 to 15, the angularly grooved upward joint 2 is formed separately and the flat fixing plate 9 is welded to the lower end of upward joint 2 by drawing back a little and a one side-toothed or a both sides-toothed washer 22 is inserted into the drawn back place. The transparent hole 10 is bored in the center of fixing plate 9. The fixing bolt 11 with its head welded to the under surface of horizontal base plate 1 projects its spiral axis vertically to the upper surface of horizontal base plate 1 from the penetrating hole 54. The washer 22 is also interposed between the nut 12 and the fixing plate 9. In the standard stair block as illustrarted in Figure 27, the downward joint 3 is inserted into the upward joint 2 and the nut 9 is fixed to the outer surface of upward joint 2 and the long hole 5 is bored in the downward joint 3. In the standard stair block as illustrated in Figure 28, the upward joint 2 is inserted into the downward joint 3 and the nut 6 is fixed to the inner surface of upward joint 2 and the long hole 5 is bored in the downward joint 3. In the standard stair block as illustrated in Figure 29, the downward joint 3 is inserted into the upward joint 2 and the nut 6 is fixed to the inner surface of downward joint 3 and the long hole 5 is bored in the upward joint. In the stair unit 4 as illustrated in Figure 28 and Figure 29, the bolt 7 is tightened from the outside. To put a cover to the stair unit 4 in the first place, an open part for inserting a driving tool must be formed in the cover and, if necessary thereafter, the open part is closed with a covering member. Also, the cover can be formed separately and the separated members of the cover put to the framework can be connected and fixed by a vis stopper or by an adhesive agent after the height between the upper and lower stair units is adjusted. In the angle-adjusting stair unit 4B as illustrated in Figure 30, the quadrilateral downward joint 3 is formed separately. The bolt 11 with its head welded to the horizontal base plate 1 projects perpendicularly from the under surface of horizontal base plate 1. The flat fixing plate 9 is welded to the upper end of downward joint 3 by drawing back a little. The one side-toothed or both sides-toothed washer 22 and the head of fixing bolt 11 are accommodated in the drawn back place. The transparent hole 10 is bored in the center of fixing plate 9 and the washer 22 is also interposed between the nut 12 and the fixing plate 9. In the angle-adjusting stair unit 4 as illustrated in Figure 31, the angularly grooved upward joint 2 is formed separately and the flat fixing plate 13 is welded to the lower end of upward joint 2 by drawing back a little and the one side-toothed or both sides-toothed washer 23 is inserted into the drawn back space. The transparent hole 14 is bored in the center of fixing plate 13. The nut 16 welded to the under surface of horizontal base plate 1 communicates with the penetrating hole 55 bored in the horizontal base plate 1. The washer 23 is also interposed between the bolt 15 and the fixing plate 13. In the angle-adjusting stair unit 4D as illustrated in Figure 32, the quadrilateral downward joint 3 is formed separately and the flat fixing plate 13 is welded to the upper end of downward joint 3 by drawing back a little. The nut 16 is welded to the under surface of horizontal base plate 1 and the one side-toothed or both sides-toothed washer 23 is inserted into the drawn back space. The transparent hole 14 is bored in the center of fixing plate 13. The washer 23 is also interposed between the bolt 15 and the fixing plate 13. In the angle-adjusting stair unit 4E as illustrated in Figure 33 and Figure 34, the flat installing plate 17 is welded to the lower end of upward joint 2 and four penetrating holes 18 are bored in the outer circumferential edge projecting from the outer side of upward joint 2. In the angle-adjusting stair unit 4F as illustrated in Figure 35, the flat installing plate 17 is welded to the upper end of downward joint 3 and four penetrating holes 18 are bored in the outer circumferential edge projecting from the outer side of upward joint 2. The present invention can be embodied in various forms. The upward joint 2 and the downward joint 3 can be formed of a regular polygonal or an irregular polygonal grooved body or a tubular body. The method for fixing the upward joint 2 or the downward joint 3 to the horizontal base plate 1 is not limited to welding and other known fixing methods can be employed. In the standard stair unit 4 in which the upward joint 2 and the downward joint 3 are not rotatable for the horizontal base plate 1, the upward joint 2 or the downward joint 3 can be integrated with the horizontal base plate 1. Even in the angle-adjusting stair unit, the upward joint 2 or the downward joint 3 which is not formed separately can be manufactured by being united with the horizontal base plate 1. Now, an embodiment of the second formataion according to the present invention will be explained hereinbelow. In the stair unit 115 for changing from the straight part to the curved part as illustrated in Figures 42 to 45, the downward joint 109 is formed of a metallic cylindrical body and the upward joint 102 formed of a quadrilateral case processed by bending a metallic plate has a longitudinal opening on its one side. The long hole 104 of upward joint 102 is bored in the side 103 and the ring-shaped horizontal seating plate 111 is welded to the central inner side of downward joint 109. In the stair unit 114 for curved part as illustrated in Figure 11 to 14, the upward joint 108 and the downward joint 109 are made of a metallic cylindrical body and the fixing bolt 110 is welded to the upper covering plate 126 of upward joint 108 and the ring-shaped horizontal seating plate 111 is welded to the central inner surface of downward joint 109. In the stair unit 116 for changing from the curved part to the straight part as illustrated in Figures 50 to 53, the upward joint 108 is formed of a metallic cylindrical body and the fixing bolt 110 is welded to the upper covering plate 126 of upward joint 108. he downward joint 103 is formed of a quadrilateral case processed by bending a metallic plate and the nut 105 is welded to the outer surface of three sides and the bolt 106 is spirally united with the nut 105 from the transparent hole 127. In the stair unit 107 for straight part as illustrated in Figures 54 to 57, the upward joint 102 and the downward joint 103 are formed of a quadrilateral case processed by bending a metallic plate and the long hole 104 of upward joint 102 is bored in three sides. The nut 105 of downward joint 103 is welded to the outer surface of its three sides and the bolt 106 is spirally united with the nut 105 from the transparent hole 127. In any stair unit, the upward joint 102, 108 and the downward joint 103, 109 form a framework of stair unit by being welded to the horizontal base plate 101 together with proper reinforcing plates. In order to improve its external appearance when installed in a building, a plastic-molded dressing cover 125 is put thereto. The cover 125 is fixed to the horizontal base plate 101 by a tapping vis which is spirally inserted into the transparent hole 130 bored in the outer circumferential edge of horizontal base plate 101 before a staircase is fixed up. When a one side-toothed washer or a both side-toothed washer 128 is inserted between the head of bolt 106 and the upward joint 102, between the upper nut 112 and the horizontal seating plate 111 and between the lower nut 113 and the horizontal seating plate 111 and fastened to its each contacting surface by tightening the bolt 106 or the upper nut 112, it can be fixed thereto very strongly and firmly. The tread 119 is fixed to the upper surface of horizontal base plate 101 by spirally inserting a vis into the spiral hole 129 bored in the outer edge of horizontal base plate 101. In order to install the tread 119 correctly at a horizontal position, the level adjusting plate can be inserted between the tread 119 and the horizontal base plate 101. The level adjusting plate is installed by spirally inserting four vises into the nuts weleded to the under surface of outer circumferential edge. It can be installed horizontally by increasing or decreasing the depth of spirally inserting those vises and the tread 119 which comes into contact with the upper surface of horizontal base plate 101 can also be installed horizontally. In the upper nut 112 and in the lower nut 113, a driving tool inserting slot 131 and a longitudinal hole 132 are bored. In another embodiment as illustrated in Figures 58 to 70, a horizontal plate 133 is welded to the central inner surface of the upward joint 108 and the fixing bolt 110 of the upward joint 108 is welded to the central part of said horizontal plate 133. And, the horizontal seating plate 111 of the downward joint 109 is formed of the bottom plate of pot-shaped cylindrical body 134 and the jaw 135 at the upper end of said cylindrical body 134 is fixed to the horizontal plate 101 by a vis 136. Other formations and operations are the same in the beforesaid embodiment. The sectional shapes of the upward joints 102, 108 and the downward joints 103, 109 are not specifically limited to those illustrations. Then, an embodiment of the third formation according to the present invention will be described. In the stair unit 215 for changing from the straight part to the curved part as illustrated in Figures 77 to 80, the downward joint 209 is formed of a metallic cylindrical body and the upward joint 202 formed of a quadrilateral case processed by bending a metallic plate has a longitudinal long hole in its one side. The long hole 204 of the upward joint 202 is bored in the three sides and the ring-shaped horizontal seating plate 211 is welded to the central inner surface of the downward joint 209. In the horizontal seating plate 211, four openings 232 are provided for inserting the 2 folds-shaped driving tool of movable case 210 around the longitudinal hole 240 for inserting a bolt 212. In the stair unit 214 for curved part as illustrated in Figure 81 to 84, the upward joint 208 and the downward joint 209 ard formed of a metallic cylindrical body. The ring-shaped horizontal seating plate 211 is welded to the central inner surface of the downward joint 209 and the bolt 212 is inserted from the logitudinal hole 240 in the center of horizontal seating plate 211. In the horizontal seating plate 211, an opening 232 is provided for inserting the driving tool of movable case 210. The horizontal plate 226 is welded to the upper end of movable case 210. The nut 213 is welded to the under surface of horizontal plate 226 and the bolt 212 is inserted from the longitudinal hole 239 of horizontal plate 226. In the horizontal plate 226, four transparent holes 231 for inserting the driving tool are provided around the longitudinal hole 239. To the lower end of movable case 210 a spiral case 237 is welded. In the inner circumference at the lower end of the upward joint 208, a female screw 238 with which said spiral case 237 will be spirally united is provided. In the stair unit 216 for changing from the curved part to the straight part as illustrated in Figures 85 to 88, the upward joint 208 is formed of a metallic cylindrical body and the downward joint 203 is formed of a quadrilateral case processed by bending a metallic plate. The nut 205 is welded to the outer surface of three sides and the bolt 206 is spirally united with the nut 205 from the transparent hole 227. The horizontal plate 226 is welded to the upper end of movable case 210. Into the nut 213 welded to the under surface of horizontal plate 226, a bolt 212 will be inserted from the longitudinal hole 239 of horizontal plate 226. In the horizontal plate 226, four transparent holes 231 for inserting a driving tool is provided. At the lower end of movable case 210, the welded spiral case 237 will be spirally united with the female screw 238 in the inner circumferential surface at the upper end of the upward joint 208. In the stair unit 207 for straight part as illustrated in Figures 89 to 92, the upward joint 202 and the downward joint 203 are formed of a quadrilateral case processed by bending a metallic plate. The long hole 204 of the upward joint 202 is bored in the three sides. The nut 205 of the downward joint 203 is welded to the outer surface of three sides and the bolt 206 is spirally united with the nut 205 from the transparent hole 227. In any stair unit, the upward joints 202, 208 and the downward joint 203,209 form a framework of stair unit by being welded to the horizontal base plate 201 together with proper reinforcing plates. In order to improve its external appearance when installed in a building, a plastic-molded dressing cover 225 is put thereto. The cover 225 is fixed to the horizontal base plate 201 by a tapping vis which is spirally inserted into the transparent hole 230 bored in the outer circumferential edge of horizontal base plate before a staircase is fixed up. When a one side-toothed washer or a both side-toothed washer 228 is inserted between the head of bolt 206 and the upward joint 202, between the bolt 212 and the horizontal seating plate 211 and between the horizontal plate and the horizontal seating plate 211 and it is fastened to its each contacting surface by tightening the bolt 206 or the bolt 212, it can be fixed thereto very strongly and firmly. The tread 219 will be fixed to the upper surface of horizontal base plate 201 by spirally inserting a vis into the four spiral holes 229 bored in the outer edge of horizontal base plate 201. In order to install the tread correctly at a horizontal position, the level adjusting plate can be inserted between the tread 219 and the horizontal base plate 201. The level adjusting plate is installed by spirally inserting four vises into the nuts welded to the under surface of outer circumferential edge. It can be installed horizontally by increasing or decreasing the depth of spirally inserting those vises and the tread 219 which comes into contact with the upper surface of horizontal base plate 201 can also be installed horizontally. In another embodiment as illustrated in Figures 93 to 105, the horizontal plate 226 is welded to the central inner surface of movable case 210 and the nut 213 is welded to the under surface of horizontal plate 226. To the upper end of the upper joint 208 a spiral case 241 is welded and the spiral case 241 is spirally united with a female screw in the lower inner circumference of movable case 210. The horizontal seating plate 211 of the downward joint 209 is formed of the bottom plate of pot-shaped cylindrical body 234 and a jaw at the upper end of said plate 201 by a vis 236. Other formations and, operations are the same as in the beforesaid embodiment. Each sectional shape of the upward joints 202, 208 and the upward joints 203,209 is not specifically limited to those illustrations, if they are inserted/united unrotatably or rotatably depending on the place where a stair unit is used. A hexagonal or octagonal or oval case can be used fittingly. Effects of the first formation according to the present invention will now be described. In the embdoiments in accordance with claims 1 and 2, a longitudinal long hole 5 is made in one side of upward joint 2 and downward joint 3 and a nut 6 is installed in the other side of upward and downward joints 2,3. The upward joint 2 and downward joint 3 are fixed by spirally inserting a bolt 7 into the nut 6 from the long hole 5. As the upper and lower stair units 4, 4 can be connected with only an upward joint 2, a downward joint 3, a bolt 7 and a nut 6, the number of constituent parts is small and material cost is thereby reduced. At the same time, it is labor-saving because the stair unit is light. In addition, it is not necessary to weld such connecting members to the upward joint 2 or to the downward joint 3. Thus, those constituent parts can be fixed easily and efficiently. As the transverse sections of the upward joint 2 and the downward joint 3 are not circular, the upper and lower stair units 2, 3 are not rotatable under the condition that the upward joint 2 and the downward joint 3 are inserted/united. Thus, a staircase can be easily fixed up by being correctly kept from its shaking. In the embodiments in accordance with claims 3 and 4 one side of the upward joint 2 and one side of the downward joint 3 are formed by being separated from the horizontal base plate 1, and a fixing plate 9 is fixed to the separated upward joint 2 or the separated downward joint 3, and a transparent hole 10 is bored on the longitudinal central line of the separately formed upward joint 2 or downward joint 3 in the said fixing plate 9, and a bolt 11 which will be inserted through the transparent hole 10 is vertically installed in the horizontal base plate 1, and the separately formed upward joint 2 or downward joint 3 is fixed to the horizontal base plate 1 by spirally uniting a nut 12 with the bolt 11 after giving a required turn to the separately formed upward joint 2 or downward joint 3 for the horizontal base plate 1, and the upward joint 2 and the downward joint 3 is fixed by spirally inserting a bolt 7 into the nut 6 fixedly installed on the side of the upward joint 2 and the downward joint 3 from the longitudinal long hole 5 bored on the one side of the upward joint 2 and the downward joint 3 and so the arrangement angle and height between the upper and lower stair units are adjustable. Thus, such stair units can be widely used in various buildings and a spiral staircase or a staircase with a landing can be fixed up optionally. In the embodiments in accordance with claims 5 and 6 one side of the upward joint 2 and one side of the downward joint 3 are formed by being separated from the horizontal base plate 1, and a fixing plate 13 is fixed to the separately formed upward joint 2 or downward joint 3, and a bolt 15 is inserted through the transparent hole 14 of fixing plate 13 bored on the longitudinal central line of the separately formed upward joint 2 or downward joint 3, and the separately formed upward joint 2 or downward joint 3 is fixed to the horizontal base plate 1 by spirally inserting the bolt 15 into the nut 16 fixedly installed in the horizontal base plate 1 after giving a required turn to the separately formed upward joint 2 or downward joint 3 for the horizontal base plate 1 with the bolt 15 as the center, and the upward joint 2 and the downward joint 3 are fixed by inserting a bolt 7 into the nut 6 fixedly installed on the other side of upward joint 2 and downward joint 3 from the longitudinal long hole 5 bored on the one side of upward joint 2 and downward joint 3 and so the arrangement angle and height between the upper and lower stair units are adjustable. Thus, such stair units can be widely used in various buildings and a spiral staircase or a staircase with a landing can be fixed uptionally. In the embodiments in accordance with claims 7 and 8 one side of the upward joint 2 and one side of the downward joint 3 are formed by being separated from the horizontal base plate 1, and an installing plate 17 is fixed to the separately formed upward joint 2 or downward joint 3, and the separately formed upward joint 2 or the downward joint 3 is fixed to the horizontal base plate 1 by spirally inserting a tapping vis 19 into the receiving hole 20 bored in the horzontal base plate 1 from the penetrating hole 18 bored in the installing plate 17 after giving a requied turn to the separately formed upward joint 2 or downward joint 3 for the horizontal base plate 1, and the upward joint 2 and the downward joint 3 are fixed by spirally inserting a bolt 7 into the nut 6 fixedly installed on the other side of upward joint 2 and downward joint 3 from the longitudinal long hole 5 bored on the one side of upward joint 2 and downward joint 3 and so the arrangement angle and height between the upper and lower stair units are adjustable. Thus, such stair units can be widely used in various buildings and a staircase with a landing or a spiral staircase can be fixed up optionally. In order to adjust the arrangement angle between the upper and lower stair units of embodiments in accordance with claims 3 to 9 , all the stair units 4A, 4B,4C are not made rotatable. Only the upward joint 2 or the downward joint 3, which is formed by being separated from the horizontal base plate 1, is made rotatable. It suffices that the relatively light upward joint 2 or downward joint 3 is kept still at its arrangement angle. As stair units can be fixed up efficiently without an assistant worker, labor cost can be reduced to a considerably degree. In the embodiment in accordance with claim 9, the upward joint and the downward joint 3 are formed of a quadrilateral case or a quadrilateral grooved body manufactured by bending and processing a metallic plate and boring or cutting in the upward joint 2 or in the downward joint 3 can be performed efficiently without a special tool. In the embodiment in accordance with claim 10, the upward joint 2 and the downward joint 3 are fixed by interposing a one side-toothed washer or a both side-toothed washer 21 between the head of bolt 7 and the upward joint 2 or the downward joint 3. So, the upward joint 2 and the downward joint 3 are connected firmly by sticking of the washer 21 to its contacting surface and the upper and lower stair units are not loosened along the longitudinal long hole. Thus, the height between each stair units is not changeable from its original measurements and the stair units can be.used in a stabilized condition. In the embodiment in accordance with claim 11, the upward joint 2 or the downward joint 3 is fixed to the horizontal base plate 1 by interposing a one side-toothed washer or a both side-toothed washer 23 between the fixing plate 13 and the horizontal base plate 1 or between the bolt 15 and the fixing plate 13, so that the upward joint 2 or the downward joint 3 can be connected firmly with the horizontal base plate 1 by sticking of the washer 23 to its contacting surface. As the upward joint 2 or the downward joint 3 is not rotatable with the bolt 15 as the center, the arrangement angle between each stair unit is not changeable and the stair units can be used in a stabilized condition. Then, effects of the second formation according to the present invention will be described. In the takedown according to the present invention as described hereinabove, the height between the stair units 107, 107 for straight part, the height between the stair unit 107 for straight part and the stair unit 115 for changing part the height between the stair unit 115 for changing part and the stair unit 114 for curved part, the height between the stair units 114,114, the height between the stair unit 114 for curved part and the stair unit 116 for changing part and the height between the stair unit 116 for changing part and the stair unit 107 for straight part are adjustable. At the same time, the arrangement angle between the stair unit 115 for changing part and the stair unit 114 for curved part, the arrangement angle between the stair units 114, 114 for curved part and the arrangement angle between the stair unit 114 for curved part and the stair unit 116 for changing part are adjustable consecutively, so that this takedown staircase can be widely used in various buildings, and a spiral staircase or a staircase provided with a landing can be fixed up optionally. And, as the rotation or movement of stair unit 114 for curved part is kept in check by being bound by the stair unit 117 for top part fixed to the floor 124 of upper storey and the stair unit 118 for base part fixed to the floor 120 of lower storey, and the stair unit 107 for straight part and the stair unit 115 for changing part which are unrotatally united with those stair units 117,118, a takedown staircase which does not cause a shake not only in whole but also in the landing or in the curved part can be provided easily. Effects of the third formation according to the present invention will be described hereinafter. In the takedown staircase according to the present invention as described hereinabove, the arrangement angle between the stair unit 215 for changing part and the stair unit 214 for curved part, the arrangement angle between the stair unit 214,214 for curved part and the arrangement angle between the stair unit 214 for curved part and the stiar unit 216 for changing part is adjustable consecutively. At the same time, the height between the stair units 207,207 for straight part, the height between the stair unit 207 for straight part and the stair unit 215 for changing part, the height between the stair unit 215 for changing part and the stair unit 214 for curved part, the height between the stair units 214, 214, the height between the stair unit 214 for curved part and the stair unit 216 for changing part and the height between the stair unit 216 for changing part and the stair unit 207 for straight part is adjustable. Consequently, it can be widely used in various buildings, and a spiral staircase or a staircase provided with a landing can be fixed up optionally. And, as the rotation or movement of stair unit 214 for curved part is held in check by being bound by the stair unit 217 for top part fixed to the floor 224 of upper storey and the stair unit 218 for base part fixed to the floor 220 of lower storey, and the stair unit 207 for straight part and the stair units 215, 216 for changing part which are unrotatably united with those stair units 217,218, a takedown staircase which does not cause a shake not only in whole but also in the landing or in the curved part can be fixed up very easily.

Claims: A stair unit adapted for attachment to further stair units so as to form a staircase, which stair unit comprises: a base plate (1) arranged to extend horizontally in an assembled staircase; a first joint part (2) upstanding from a rear portion of the base plate (1); a second joint part (3) depending from a front portion of the base plate (1), said upstanding and depending joint parts (2,3) being arranged to mate with similar joint parts of further stair units, said upstanding joint part (2) with a depending joint part (3) of an upper further stair unit, and said depending joint part (3) with an upstanding joint part (2) of a lower further stair unit; and a tread part (8) for fixing to an upper surface of the base plate (1); characterised in that there is defined in said upstanding joint part (2), a hole (5) which is elongate in the upstanding direction; and in that there is a nut (6) fixedly mounted on said depending joint part (3); wherein the depending joint part of one unit is securable to the upstanding joint part of another unit by means of a bolt (7) extending through the elongate hole (5) of the upstanding part (2) and screwed into a nut of the depending part; and in that the joint parts (2,3) are of non-circular transverse section, whereby on mating with the joint parts (2,3) of further units, relative rotation is prevented. A stair unit adapted for attachment to further stair units so as to form a staircase, which stair unit comprises: a base plate (1) arranged to extend horizontally in an assembled staircase; a first joint part (2) upstanding from a rear portion of the base plate (1); a second joint part (3) depending from a front portion of the base plate (1), said upstanding and depending joint parts (2,3) being arranged to mate with similar joint parts of further units, said upstanding joint part (2) with a depending joint part (3) of an upper further stair unit, and said depending joint part (3) with an upstanding joint part (2) of a lower further stair unit; and a tread part (8) for fixing to an upper surface of the base plate (1); characterised in that there is defined in a said depending joint part (3), a hole which is elongate in the depending direction; and in that there is a nut (6) fixedly installed on said upstanding joint part (2); wherein the depending joint part of one unit is securable to the upstanding joint part of another unit by means of a bolt (7) extending through the elongate hole (5) of the depending part and screwed into a nut of the depending part; and in that the joint parts (2,3) are of non-circular transverse section, whereby on mating with the joint parts (2,3) of further units, relative rotation is prevented. A stair unit (4A) according to claim 1 or 2 wherein the upstanding joint part (2) is formed non-unitarily with the base plate (1) and is provided with a fixing plate (9) therein having a hole (10) formed therein on the longitudinal axis of the upstanding joint part (2), and wherein an upstanding bolt (11) is fixed to the base plate (1), the upstanding joint part (2) being connected to the base plate (1) by arrangement of the joint part (2) over the bolt (11) of the base plate (1) so that the upstanding bolt (11) extends through the hole (10) and is secured by means of a further nut (12). A stair unit (4B) according to claim 1 or 2 wherein the depending joint part (3) is formed non-unitarily with the base plate (1) and is provided with a fixing plate (9) therein having a hole (10) formed therein on the longitudinal axis of the depending joint part (3), and wherein a depending bolt (11) is fixed to the base plate (1), the depending joint part (3) being connected to the base plate (1) by arrangement of the joint part (3) over the bolt (11) of the base plate (1) so that the depending bolt (11) extends through the hole (10) and is secured by means of a further nut (12). A stair unit (4C) according to claim 1 or 2 wherein the upstanding joint part (2) is formed non-unitarily with the base plate (1) and is provided with a fixing plate (13) therein having a through hole formed on the longitudinal axis thereof, wherein a further nut (16) is fixedly installed on the base plate (1), and wherein a bolt (15) is inserted through the hole (14) of the fixing plate (13) and is screwed into the fixed nut (16) on the base plate (1) to secure the joint part (2) to the base plate (1). A stair unit (4D) according to claim 1 or 2 wherein the depending joint part (3) is formed non-unitarily with the base plate (1) and is provided therein with a fixing plate (13) having a through hole (14) on a longitudinal axis of the depending joint part (3), wherein a further nut (16) is fixedly installed on the base plate (1) and wherein a bolt (15) inserted through the through hole of the fixing plate (13) is screwed into the fixed nut (16) to secure the depending joint part (3) on the base plate (1). A stair unit (4E) according to claim 1 or 2 wherein the upstanding joint part (2) is formed non-unitarily with the base plate (1) and is provided with an installing plate (17) fixed at the base of the upstanding joint part (2), the installing plate (17) having at least one through hole and the base plate (1) having at least one corresponding receiving hole, and wherein the joint part (2) and base plate (1) are secured together by means of a tapping vis (19) inserted through the or each through hole in the installing plate (17) into the receiving hole or holes (20). A stair unit (4F) according to claim 1 or 2 wherein the depending joint part (3) is formed non-unitarily with the base plate (1), and is provided with an installing plate (17) fixed at an upper portion of the upstanding joint part (3), the installing plate (17) having at least one through hole and the base plate (1) having at least one corresponding receiving hole, and wherein the joint part (3) and base plate (1) are secured together by means of a tapping vis (19) inserted through the or each through hole in the installing plate (17) into the receiving hole or holes (20). A stair unit according to any preceding claim wherein the upstanding and depending joint parts (2,3) both comprise tubular parts of quadrilateral section formed by bending of a metal plate, optionally provided with grooves therein. A stair unit according to any preceding claim wherein a washer (22) provided with teeth on one or both faces thereof is interposed between a head of the bolt (7) for insertion into the elongate hole (5) and that joint part (2,3) provided with the elongate hole (5) therein. A stair unit according to claim 3 or 4 wherein a washer (22) provided with teeth on one or both faces thereof is interposed between the fixing plate (9) and the base plate (1) and/or between the further nut (12) and the fixing plate (9). A stair unit according to claim 5 or 6 wherein a washer (23) provided with teeth on one or both faces thereof is interposed between the fixing plate (30) and the base plate (1) and/or between the bolt (15) for securing the joint part (2,3) to the base plate (1) and the fixing plate (13). A combination of stair units including a first unit type (107), and units selected from second (114), third (115), fourth (116), fifth (117) and sixth (118) unit types and which connect together to form a staircase, wherein; the first unit type (107) is a stair unit as claimed in claim 1 or 2; the second unit type (114) has a base plate (101) which, in the assembled staircase is arranged to extend horizontally, a joint part (108) upstanding from a rear portion of the base plate (101), a joint part (109) depending from a front portion of the base plate (101), an upstanding bolt (110) installed centrally in an upper portion of the upstanding joint part (108), a seating plate (111) which is disposed in the depending joint part (109), said upstanding joint part (108) and said depending joint part (109) being arranged to mate with similar joint parts of a further unit, said upstanding joint part (108) with a depending joint part of an upper further stair unit, and said depending joint part (109) with an upstanding joint part of a lower further stair unit, such that when in mating relation, relative rotation of the joint parts is possible, the fixing bolt (110) extending through the through hole of a seating plate (111) of a further unit, the units being secured in position by means of upper (112) and lower (113) nuts arranged on the upstanding bolt (110) on opposite sides of the seating plate (111); the third unit type (115) has a base plate (101) which, in the assembled staircase is arranged to extend horizontally, a joint part (102) upstanding from a rear portion of the base plate (101), and a joint part (103) depending from a front portion of the base plate (101), a hole (104) defined in the upstanding joint part (102) which is elongate in the upstanding direction of the joint part (102), a seating plate (111) which is disposed in the depending joint part (109) provided with a through hole therein, said upstanding joint part (102) being arranged to mate with a depending joint part (103) of the first unit type (107), such that relative rotation of the mating joint parts (102,103) is prevented, and secured by inserting a bolt (106) through the elongate hole (104) and screwing into the nut (105) of the first stair unit type (107), the depending joint part (109) being arranged to mate with the upstanding joint part (108) of the second unit type (114) such that relative rotation of mating joint parts is possible, the fixing bolt (110) of the second unit type (114) extending through the through hole of the seating plate (111) and, when mating, the depending joint parts (109) and upstanding joint part (108) of the second unit type (114) being secured by tightening upper (112) and lower (113) nuts arranged on the bolt (110) onto opposite faces of the seating plate (111); the fourth unit type (116) has a base plate (111) which, in an assembled staircase is arranged to extend horizontally, a joint part (108) upstanding from a rear portion of the base plate (101), and a joint part (109) depending from a front portion of the base plate (101), an upstanding bolt (110) installed at an upper portion of the upstanding joint part (108), and a nut (105) fixed in the depending joint part (103), the upstanding joint part (108) being arranged to mate with a depending joint part (109) of a second unit type (114), such that when mated, relative rotation is possible, the fixing bolt (110) extending into the seating plate (111) of the second unit type (114) and being secured by tightening upper (112) and lower (113) nuts arranged on the bolt onto opposite faces of the seating plate (111) of the second unit type (114), the depending joint part (109) being arranged to mate with an upstanding joint part (102) of the first stair unit type (107) such that relative rotation is not possible, and when mated are secured by means of a bolt (106) inserted through the elongate hole (104) of the upstanding joint part (102) and screwed into the nut (105); the fifth unit type (117) for use as the uppermost step of a staircase, has a base plate (101) which in an assembled staircase is arranged to extend horizontally, a joint part (103) depending from a front portion of the base plate (101), a nut (105) fixedly installed therein, the depending joint part (103) being arranged to mate with an upstanding joint part (102) of a first stair unit type (107), such that when mated, relative rotation is not possible, the joint parts being secured by means of a bolt (106) of the first stair unit type (107) inserted through the elongate hole (104) of the upstanding joint part (102) of the first stair unit (107) and screwed into the nut (105), the base plate (107) being further adapted for fixing to an upper storey of a building; the sixth stair unit type (118) for use at a lowermost position of a staircase, has a base plate (101) which in an assembled staircase is arranged to extend horizontally, having a joint part (102) upstanding from a rear portion thereof and provided with a hole (104) formed therein, elongate in the upstanding direction, said upstanding joint part (102) being arranged to mate with a depending joint part (103) of a first stair unit type (107) such that when mated, relative rotation is not possible, and being secured by insertion of a bolt (106) through the elongate hole (104) into the nut (105) of the depending joint part (103) of the first stair unit type (107), said base plate (101) being further adapted for fixing to a floor of a lower storey of a building; and, treads (119) are provided for fixing to upper surfaces of respective base plates (101) of each stair unit (107,114,115,116,117,118). A combination of stair units according to claim 13 comprising units of each of said first (107), second (114), third (115), fourth (110), fifth (117) and sixth (118) types. A combination of stair units including a first unit type (207), and units selected from third (215), fifth (217), sixth (218), seventh (214) and eighth (216) types and which connect together to form a staircase, wherein; the first unit type (207) is a stair unit as claimed in claims 1 or 2; the third unit type (215) has a base plate (201) which, in the assembled staircase is arranged to extend horizontally, a joint part (202) upstanding from a rear portion of the base plate (201), and a joint part (203) depending from a front portion of the base plate (201), a hole (204) defined in the upstanding joint part (202) which is enlongate in the upstanding direction of the joint part (202), a seating plate (211) which is disposed in the depending joint part (209) provided with a through hole therein, said upstanding joint part (202) being arranged to mate with a depending joint part (203) of the first unit type (207), such that relative rotation of the mating joint parts (202,203) is prevented, and secured by inserting a bolt (206) through the elongate hole (204) and screwing into the nut (205) of the first stair unit type (207), the depending joint part (209) being arranged to mate with an upstanding joint part (208) of the seventh unit type (214) such that relative rotation of interlocked joint parts is possible, the fixing bolt (210) of the seventh unit type (214) extending through the through hole of the seating plate (211) and, when mated, the depending joint parts (209) and upstanding joint part (208) of the seventh unit type (214) being secured by tightening upper (212) and lower (213) nuts arranged on the bolt (210) onto opposite faces of the seating plate (211); the fifth unit type (217),for use as the uppermost step of a staircase, has a base plate (201) which in an assembled staircase is arranged to extend horizontally, a joint part (203) depending from a front portion of the base plate (201), a nut (205) fixedly installed therein, the depending joint part (203) being arranged to mate with an upstanding joint part (202) of a first stair unit type (207), such that when mated, relative rotation is not possible, the joint parts being secured by means of a bolt (206) of the first stair unit type (207) inserted through the elongate hole (204) of the upstanding joint part (202) of the first stair unit (207) and screwed into the nut (205), the base plate (207) being further adapted for fixing to an upper storey of a building; the sixth stair unit type (218) for use at a lowermost position of a staircase, has a base plate (201) which in an assembled staircase is arranged to extend horizontally, having a joint part (202) upstanding from a rear portion thereof and provided with a hole (204) formed therein, elongate in the upstanding direction, said upstanding joint part (202) being arranged to mate with depending joint part (203) of a first stair unit type (207) such that when mated, relative rotation is not possible, and being secured by insertion of a bolt (206) through the elongate hole (204) which is screwed into the nut (205) of the depending joint part (203) of the first stair unit type (207), said base plate (201) being further adapted for fixing to a floor of a lower storey of a building; and, the seventh stair unit type (214) has a base plate (201) which in the assembled staircase is arranged to extend horizontally, a joint part (208) upstanding from a rear portion of the base plate (201), and a joint part (209) depending from a front portion of base plate (201), a casing part (210) mounted for rotation on an upper end of the upstanding joint part (208) having a plate part (226) on the upper surface thereof, provided at its centre with a nut (213) which is fixed thereto, a seating plate (211) fixed within the depending joint part (209) having a through hole (240) therein, the depending joint part (209) being adapted to mate with the upstanding joint part (208) of another unit of the seventh unit type (214), such that relative rotation is possible, the plate part (226) thereof abutting the seating plate (211) and being connected thereto by means of a bolt (212) screwed through the hole (240) of the seating plate (211), into the nut (213) of the movable casing part (210); the eighth stair unit type (216) has a base plate (201) which in the assembled staircase is arranged to extend horizontally, a joint part (208) upstanding from a rear portion of the base plate (201), and a joint part (209) depending from a front portion of the base plate (201), a casing part (210), mounted for rotation on an upper end of the upstanding joint part (208) having a plate part (226) on the upper surface thereof, and provided at its centre with a nut (213) fixed thereto, a further nut (205) fixed on the depending joint part, the upstanding joint part (208) being adapted to mate with the depending joint part (209) of a unit of the seventh stair unit type (214) such that relative rotation is possible, with the plate part (226) abutting the fixing plate (211) of the seventh type unit (214), and is connected thereto by means of a bolt (212) screwed through the hole (240) of the seating plate (211) into the nut (213) of the movable casing part (210), and the depending joint part (203) being adapted to mate with the upstanding joint part (202) of a first stair unit type (207) such that relative rotation is prevented, and secured by inserting a bolt (206) through the elongate hole (204) of the first unit type (207) and screwing into the further nut (205); and, treads (219) are provided for fixing to upper surfaces of respective base plates (201) of each stair unit (207,214,215,216,217,218). A combination of stair units according to claim 15 comprising stair units of each of said first (207), third (215), fifth (217), sixth (218), seventh (214) and eighth (216) types.

Inventors: YAMAZAKI, KEIICHIROU
Applicants: YAMAZAKI, KEIICHIROU
Application year: 1990
Main classification: E04F11
IPC codes: E04F11