Terminal and cramping connector

Abstract: The present invention comprises a cramping connector, comprising: at least one terminal having a plurality bladeportions and a housing for retaining the terminal and for positioning a plurality of wires one over the other such that the wires are pressed into the corresponding blade portions, when the housing is formed or assembled the plurality of blade portions being arranged at or having same or different heights.

Description: The present invention relates to a cramping connector and, particularly to a cramping connector in which a plurality of blade portions are held such that slits thereof open in the same direction. In a known cramping terminal, slit-like parallel blade portions are formed in flat metal strips in order to arrange terminals provided with the blade portions perpendicularly to two parallelly arranged wires. The respective blade portions are formed to have the same height, and are arranged side by side in the case of connecting a plurality of wires. With the above prior art cramping connector, since the wires to be connected are only arranged side by side, there are not a wide range of applications. Further, the arrangement of the wires, as a whole, is invariably wide. A known cramping terminal of this type is a double-sided cramping terminal disclosed in Japanese Unexamined Utility Model Publication No. 6-62468 shown in FIG. 37. In this double-sided cramping terminal, separately formed upper and lower covers 2, 3 are fittable to a plate-like housing 1 from above and below, respectively. Fittings 4 are so pressed into the housing 1 as to project from the upper and lower surfaces of the housing 1. Wires 5 are pressed to be connected with the fittings 4 on the upper and lower surfaces of the housing 1. Specifically, the wires are arranged on the upper surface of the housing 1 and the upper cover 2 is fitted to press the wires to be connected with the fittings 4 after being positioned. subsequently, the housing 1 is turned upside down. Wires are arranged in a similar manner, and the lower cover 3 is fitted to press the wires to be connected with the fittings 4. With the above double-sided cramping connector, the connection operation is cumbersome because the wires have to be connected in order, i.e. first on the upper surface and then on the lower surface or vice versa, and the housing has to be turned upside down in the middle of the operation. US-A-4 778 405 discloses an electrical connector for connecting a pair of side-by-side tap wires to through wires comprising a generally T-shaped housing having side-by-side parallel channels extending through the head for the through wires and having parallel side-by-side channels extending into te free end of the stem for the tap wires. The terminals are substantially L-shaped and offset slightly from each other. US-A-4 988 311 discloses a terminal block for providing electrical connection to insulated wire pairs. An entrance port on the block includes a blade for separating the wires as they are inserted therein. The wires are then positioned above a respective one of a pair of insulation displacement contacts. Pressure applied to the top of the block, as by screwing, drives each wire into its associated contact thereby causing penetration of the insulation for electrical connection. US-A-5 199 899 discloses a device for electrically connecting two conductors which is provided with a first U-shaped electrical connection component with a base and two sides, each side incorporating a slot widening at its part opening onto its free end. One of the sides comprises, close to the base part, a connecting band extending substantially perpendicularly to the edge of the side and integral with one of the sides of the second U-shaped electrical component with a base part and a second side, the sides of the second connection component incorporating slots widening at their part opening onto their free edge, the connecting band being bent so that the two components are substantially perpendicular to each other and the free edges of the sides of one of the components extending in a direction opposite to that in which the free edges of the sides of the other component extend. It is the object of the invention to provide a cramping connector having an improved wire arrangement operability. This object is fulfilled by a cramping connector having the features disclosed in claim 1. Preferred embodiments are defined in the dependent subclaims. According to the present invention there is provided cramping connector which ensures a wire arrangement with an improved degree of freedom and/or in a compact manner. Accordingly, there is provided a cramping connector, comprising: at least one terminal having a plurality blade portions, in particular blade parts, arranged on a same plane or having different heights, and a housing for retaining the terminal and for positioning a plurality of wires one over the other, such that the wires are pressed into the corresponding blade portions, in particular blade parts, when the housing is formed or assembled. The housing furthermore comprises wire retainers for fixedly retaining the plurality of wires on the housing and positioning them with respect to the corresponding blade portions. According to a preferred embodiment of the invention, the housing comprises at least a pair of casings. Preferably, the plurality of wires is positioned such that, ends of branch wires of the plurality of wires face the blade portions at one side and that main wires of the plurality of wires are inserted between the blade portions at the one side and face the blade portions at the other side, wherein the respective wires are pressed into the corresponding blade portions when the housing, in particular when the pair of casings is assembled. Further preferably, the housing comprises first grooves for accommodating wires to be connected with first blade portions having substantially the same height, the first grooves intersecting under an angle between 0° and 180°, preferably about 45°, 60°, 90°, 120° and/or 135°, with at least second grooves for wires to be connected with second blade portions having one or more heights different than the first grooves, the terminals being particularly mounted at the intersections of the grooves, and/or wherein the housing comprises wire pressing portions which come into contact with the wires so as to press the wires into the blade portions. Most preferably, the blade portions are obliquely arranged in the housing. According to a preferred embodiment of the invention, there is provided a cramping connector, comprising at least one terminal comprising a plurality of blade parts and/or blade portions being arranged at or having different heights, and a housing for accommodating and/or retaining the terminal such that wires are connected, in particular pressed to be connected with the blade parts and/or blade portions. According to a preferred embodiment of the invention, the housing retains a main wire and a branch wire branched from the main wire in its intermediate position, in particular one over the other., the first grooves intersecting under an angle between 0° and 180°, preferably about 45°, 60°, 90°, 120° and/or 135°, with at least second grooves for wires to be connected with second blade portions of other heights than the first grooves, particularly in a manner similar to that of a network and, the terminals being particularly mounted at the intersections of the grooves, and/or wherein the housing comprises wire pressing portions which come into contact with the wires so as to press the wires into the blade portions. Preferably, the terminal is formed by bending a metal strip, particularly in V-shape, so as to form surfaces intersecting, in particular substantially perpendicular to the longitudinal directions of the wires to be connected and in particular wherein the terminal comprises a slit in each surface from an edge, wherein the edge having a steplike contour. According to still a further embodiment, the blade portions are displaced with respect to forward and backward directions, the housing comprising a first casing for arranging and/or retaining the terminals, in particular side by side while orienting the terminals in the same direction, and retaining branch wires by placing them, particularly ends thereof on first blade portions, and a second casing which is fittable on the first casing and is adapted to retain main wires such that the main wires face corresponding second blade portions, the first blade portions having in particular a lower height than the second blade portions. Preferably, the terminal is formed by forming slits in the opposite ends of a strip from front end portions thereof and bending at least once the opposite ends substantially at an angle, in particular at a right angle in the same direction by different lengths or by forming two or more slits on portions of a strip from the lateral side thereof and bending the strip at an angle along a direction substantially in parallel to the slits, the slits having a different length and/or the side portions of the strips being stepped, wherein particularly the blade portions particularly of different heights are displaced in a lateral direction while facing parallel to each other. Still further preferably, the blade portions are obliquely arranged in the housing. According to a most preferred embodiment, the height difference of the blade portions is substantially equal to or greater than the thickness of the wires. According to a preferred embodiment of the invention, there is provided a cramping connector, comprising: a terminal comprising a plurality of blade portions of different heights which extend in the same direction, and a housing for accommodating and retaining the terminal such that wires are pressed to be connected with the blade portions. Accordingly, the plurality of blade portions extending in the same direction are so arranged as to have different heights in the terminal. Wires can be pressed to be connected with the blade portions having different heights when the terminal is accommodated in the housing. Accordingly, the connected wires can be arranged at different heights. As described above, since the plurality of blade portions having different heights are provided, the wires can be arranged at different heights, thereby improving a degree of freedom. In this case, the width of the cramping terminal can be narrowed if the wires are arranged in two stages. According to a further embodiment of the invention, there is provided a cramping connector, comprising: a housing for retaining a main wire and a branch wire branched from the main wire in its intermediate position one over the other, and a terminal which comprises a blade portion for the upper wire and another blade portion for the lower wire, the blade portions having different heights and being aligned along the longitudinal direction of the wires, and is accommodated in the housing such that the main and branch wires are pressed to be connected with the blade portions thereof. Accordingly, the housing retains the main wire and the branch wire branched from the main wire in its intermediate position one over the other. When the main wire is inserted, while the end of the branch wire is inserted into the housing, through the housing over the branch wire, the main wire is placed on the branch wire in the housing. The terminal is accommodated in the housing, and the branch wire is pressed to be connected with the blade portion for the lower wire and the main wire is pressed to be connected with the blade portion for the upper wire in its position where it is not placed on the branch wire. In other words, a single terminal connected with the main wire and the branch wire placed one over the other. If such terminals are arranged side by side, the wires can be arranged in two vertical stages. Thus, since the main wire and the branch wires are connected, placed one over the other, the height of the cramping connector can be made smaller. Further preferably, the housing comprises: a lower casing formed with a wire path extending in a lateral direction and an opening in an upward direction for accommodating the terminal such that the blade portions extend in the upward direction, and retaining the lower wire placed on the blade portion therefor, and an upper casing for closing the opening of the lower casing and retaining the upper wire such that the upper wire faces the blade portion therefor when the upper casing closes the opening of the lower casing. Accordingly, the lower casing constructing the housing comprises the wire path extending in the lateral direction and is open in the upward direction, and the terminal is accommodated such that the blade portions extend in the upward direction. The branch wire as the lower wire is placed and retained on the blade portion for the lower wire. On the other hand, the upper casing constructing the housing is capable of retaining the main wire as the upper wire. When the upper casing closes the opening of the lower casing while retaining the main wire, the main wire faces the blade portion for the upper wire of the terminal in the lower casing and the branch wire faces the blade portion for the lower wire. By pressing the upper and lower casings, the wires are connected with the corresponding blade portions. Thus, the connection can be made only by fitting the lower casing and the upper casing retaining the branch wire and the main wire together, making an operation easier. According to a further preferred embodiment of the invention, there is provided a cramping connector, comprising: a plurality of terminals each having a plurality of blade portions of different heights which are so arranged as to cross the longitudinal directions of wires to be connected therewith, a first casing comprising an open surface and grooves for accommodating wires to be connected with the blade portions of the same height in the plurality of terminals in parallel with each other, the grooves intersecting with grooves for wires to be connected with the blade portions of the other heights in a manner similar to that of a network and the terminals being mounted at the intersections of the grooves, and a second casing for covering the open surface of the first casing, the second casing comprising wire pressing portions which come into contact with the wires so as to press the wires into the blade portions. Accordingly, in the first casing having the open surface, the substantially parallel grooves for accommodating the wires to be connected are formed in a manner similar to that of a network. The wires are pressed into these grooves through the open surface to be accommodated therein. On the other hand, the terminals each having a plurality of blade portions of the heights which are changed or varied particularly with respect to or along the longitudinal directions of the wire(s) are mounted at the intersections of the grooves. Accordingly, the wires can be connected at the intersections. When the second casing is fitted to the first casing after the wires are accommodated in the first casing, the wire pressing portions come into contact with the wires so as to press them into the blade portions, thereby facilitating the connection by the blade portions in the terminals and holding the wires. As described above, since the substantially parallel grooves are formed for each group of wires to be connected, the plurality of wires are so accommodated in one casing as to intersect in the manner similar to the network. Further, non-intersecting portions of the wires are held by being pressed by the other casing. Accordingly, there can be provided a cramping connector which allows the wires to be arranged through one open surface, thereby improving an operability. In other words, there is provided a cramping connector which ensures a compact wire arrangement. Preferably, each terminal is formed by bending a metal strip in V-shape so as to form surfaces perpendicular to the longitudinal directions of the wires to be connected and making a slit in each surface from an edge. Accordingly, the metal strip is so bent a number of times corresponding to the number of the wires to be connected, thereby forming a plurality of surfaces perpendicular to the longitudinal directions of the wires. Further, the slit is formed in each surface from the edge. The terminals are connected with the intersecting wires at the intersections of the grooves in the first casing. Thus, the terminals can be easily formed only by bending the strips. Further preferably, the edge of each terminal where the slits are formed has a steplike contour. Accordingly, since the edge of each terminal where the slits are formed has a steplike contour, if the slits of the same depth are formed, the blade portions of different heights can be formed in the respective surfaces. Thus, since the edge has a steplike contour, the respective blade portions are easily distinguishable and the heights thereof are easily adjustable. Still further preferably, a metal strip is bent in two at right angles and wherein the first and second casings are formed with two groups of grooves perpendicularly intersecting with each other in a manner similar to that of a checkerboard. Accordingly, the first and second casings are formed with two groups of grooves intersecting with each other in a manner similar to that of a checkerboard, and the terminals each formed by bending a metal strip in two at right angles to form blade portions perpendicular to each other are mounted at the intersections where the wires intersect. Accordingly, the wires are connected with the blade portions and held by the casings by arranging and accommodating the wires in the grooves of the first casing in the manner similar to that of the checkerboard and by covering the first casing with the second casing. Thus, since the grooves intersect at right angles in the manner similar to that of the checkerboard so as to correspond to two groups of wires, the construction can be simplified. According to a further preferred embodiment of the invention, there is provided a cramping connector, comprising: a plurality of terminals each having blade portions of different heights which are displaced with respect to forward and backward directions, a first casing for arranging and retaining the plurality of terminals side by side while orienting the terminals in the same direction, and retaining branch wires by placing ends thereof on the lower blade portions, and a second casing which is fittable on the first casing from above to form a single unit, is adapted to retain main wires such that the main wires face the corresponding higher blade portions, and is formed with such projections that face the corresponding lower blade portions between the main wires. Accordingly, since the first casing retains the plurality of terminals by arranging them side by side while orienting them in the same direction, the lower and higher blade portions are arranged side by side with one in front of the other. When the branch wires are retained by the first casing and the main wires are retained by the second casing, the ends of the branch wires are placed on the lower blade portions of the terminals in the first casing and the main wires are retained on the projections in the second casing. When the first and second casings are fitted into a single unit, the main wires are pressed against the higher blade portions to be connected therewith, whereas the branch wires are pressed against the projections between the main wires to be connected with the lower blade portions. As described above, since the main and branch wires are connected while being arranged in two vertical stages, the wire arrangement can be made more compact as compared with the case where the wires are arranged only side by side. Further, since the branch and main wires are connected with the blade portions of different heights between the casings, there can be provided a cramping connector capable of fully pressing the branch wires to securely connect them with the blade portions. In other words there is provided a cramping connector having an improved wire arrangement operability. Preferably, each terminal is formed by forming slits in the opposite ends of a strip from end portions thereof and bending the opposite ends substantially at right angles in the same direction by different lengths. Accordingly, by forming the slits in the opposite ends of the strip from the end portions thereof and bending the opposite ends substantially at right angles in the same direction by different lengths, the terminal is allowed to have the blade portions formed with the slits of different heights at its upright sides. Thus, the terminal can be easily formed only by bending the opposite ends of the strip in the same direction. Further preferably, the blade portions of different heights are displaced in a lateral direction while facing parallel to each other. Accordingly, since the blade portions of different heights are displaced in the lateral direction while facing parallel to each other, if the branch wires are connected at right angles with the lower blade portions and the main wires are connected at right angles with the higher blade portions, the branch and main wires are parallel to and displaced from each other when viewed from above. Thus, since the blade portions of the terminal are displaced along the forward and backward directions and the lateral direction in advance, the respective wires can be arranged with respect to the axial direction of the casings, allowing the casings to have simpler constructions. Still further preferably, the blade portions of different heights are obliquely arranged in the first casing. Accordingly, since the blade portions of different heights are obliquely arranged in the first casing, if the branch and main wires are arranged parallel to each with respect to an axis relative to or basing on the first casing, they are parallel to and displaced from each other while being obliquely connected with the corresponding blade portions. Thus, since the blade portions are displaced along the forward and backward directions and the lateral direction merely by obliquely arranging the terminals, the construction can be simplified. According to a further preferred embodiment, there is provided a cramping connector, comprising: a plurality of terminals having blade portions shifted along forward and backward directions, and a pair of casings for retaining the plurality of terminals along a lateral direction while orienting them in the same direction, such that ends of branch wires face the blade portions at one side and that main wires are inserted between the blade portions at the one side and face the blade portions at the other side, wherein the respective wires are pressed into slits formed in the corresponding blade portions when the pair of casings are assembled. Accordingly, the terminals having the blade portions shifted along the forward and backward directions are arranged along the lateral direction while orienting them in the same direction, the branch wires face the blade portions at the one side, and the main wires face the blade portions at the other side and are inserted between the blade portions at the one side. More specifically, the branch and main wires are alternately arranged, and their positions of connection with the blade portions are alternately shifted substantially along the forward and backward directions substantially in a zigzag manner. Accordingly, as compared with the case where the positions of connection are arranged side by side in a row, the cramping connector can be narrower. Further, since the branch and main wires are pressed into the slits of the blade portions when the pair of casings are assembled, the assembling and the connection can be simultaneously performed. Thus, when the main and branch wires are alternately arranged and connected with the corresponding blade portions, their positions of connection are alternately shifted along the forward and backward directions. Thus, the cramping connector can be narrower than the prior art connector in which the positions of connection are arranged side by side in a row. Preferably, each terminal is formed by forming the slits at opposite ends of a strip and by bending the opposite ends substantially at right angles in the same direction. Accordingly, each terminal has, at its opposite ends, two blade portions formed with a slit which are shifted along the forward and backward directions. Thus, by bending the opposite ends of the strip in the same direction, the terminal having the blade portions shifted along the forward and backward directions can be easily formed. Further preferably, the blade portions shifted along the forward and backward are opposed in parallel and shifted along a lateral direction. Accordingly, if the branch wires are pressed at right angles against the front blade portions to be connected therewith and the main wires are pressed at right angles against the rear blade portions to be connected therewith, the branch and main wires are arranged in parallel when viewed from above and shifted to each other. Thus, since the blade portions of the terminal are shifted along the forward and backward directions as well as along the lateral direction, the respective wires can be arranged with respect to the axis of the casings. Thus, the construction of the casings can be simplified. Still further preferably, the terminals are obliquely arranged in the casings. Accordingly if the branch and main wires are arranged in parallel with respect to an axis of the casings, the branch and main wires are shifted in parallel to each other while being obliquely connected with the corresponding blade portions. Thus, by obliquely arranging the terminals, the blade portions can be shifted along the forward and backward directions as well as along the lateral direction, thereby simplifying the construction. Most preferably, a surface of the casing which is to face a pressing device is so indented and embossed as to conform to a pressing surface of the pressing device. Thus, this surface of the casing and the pressing surface of the pressing device are fitted to each other without experiencing any lateral displacement while the casings are pressed to be assembled Thus, since the pressing device and the casings are substantially engaged along a pressing direction, the casings can be securely pressed to be assembled without experiencing any lateral displacement. These and other objects, features and advantages of the present invention will become more apparent upon a reading of the following detailed description and accompanying drawings in which: FIG. 1 is an exploded perspective view of a cramping connector according to a first embodiment of the invention, FIG. 2 is a perspective view partly in section of a partly assembled state of a lower casing of the cramping connector, FIG. 3 is a perspective view partly in section of a partly assembled state of an upper casing of the cramping connector, FIG. 4 is a perspective view partly in section partly showing lower and upper casings of a cramping connector according to a second embodiment, and FIG. 5 is a perspective view of a completely assembled cramping terminal, FIG. 6 is a perspective view of a cramping connector according to a third embodiment of the invention in its assembled state, FIG. 7 is an exploded perspective view of the cramping connector, FIGS. 8 and 9 are perspective views of a terminal of the cramping connector, FIGS. 10 and 11 are perspective and plan views of a terminal according to a fourth embodiment, respectively, FIG. 12 is a development of a terminal according to a fifth embodiment, FIG. 13 is a fragmentary enlarged perspective view of the mounted terminal, FIG. 14 is a schematic plan view of a housing a according to a sixth embodiment, FIGS. 15 and 16 are sections along A-A of a housing and a cover of FIG. 6, FIGS. 17 and 18 are sections along B-B of the housing and the cover of FIG. 6, FIG. 19 is a fragmentary perspective view of a connection at the terminal, and FIG. 20 is an exploded perspective view of a cramping connector according to a seventh embodiment of the invention, FIG. 21 is a plan view of terminals of the cramping connector, FIG. 22 is a plan view of terminals according to an eighth embodiment, FIG. 23 is a perspective view of terminals according to a ninth embodiment, FIG. 24 is a perspective view of a first casing mounted with the terminals, FIG. 25 is a perspective view of the first and second casings of the cramping connector with a branch wire and a main wire arranged therein, respectively, FIG. 26 is a perspective view of the rear surface of the second casing, FIG. 27 is a front view showing relative positions of projections of the second casing, FIG. 28 is a plan view showing arranged branch and main wires according to a tenth embodiment, and FIG. 29 is a perspective view of the cramping connector in its assembled state. FIG. 30 is a perspective view of a cramping connector as another modification, FIG. 31 is an exploded perspective view partly in section of a lower casing of the cramping connector of FIG. 30, FIG. 32 is a perspective view partly in section of the lower casing of the cramping connector of FIG. 30, FIG. 33 is a section of the cramping connector of FIG. 30 when no branch wire is set, FIG. 34 is a section of the cramping connector of FIG. 30 when a branch wire is set, FIG. 35 is a perspective of an upper casing of the cramping connector of FIG. 30 when viewed from below, and FIG. 36 is a perspective of the cramping connector of FIG. 30 in its assembled state. FIG. 37 is an exploded perspective view of a prior art cramping connector. In FIG. 1, each terminal 10 is formed by making slits at the opposite ends of a strip 11 to form blade portions or blade carrying parts 12a, 12b having (or including or carrying) blade portions 12a1, 12b1 and by bending the blade parts 12a, 12b such that the terminal 10 has a substantially U-shaped cross section. The blade portions 12a, 12b are formed such that the rear blade part 12a and/or the rear blade portion 12a1 is higher than the front blade part 12b and/or the front rear portion 12b1, i.e. the blade parts 12a, 12b and/or blade portions 12a1, 12b1 have different heights. In this embodiment, the terminal 10 is formed by bending the opposite ends of the strip 11 by different lengths. Since it is sufficient to at least differ the heights of a plurality of blade parts 12a, 12b and/or of blade portions 12a1, 12b1, the opposite ends of the strip 11 may be bent at different angles. However, in the case that the opposite ends of the strip 11 are bent in the same direction such that the slits are aligned as in this embodiment, when being pressed into the slits to be connected, two wires are placed one over another, realizing a compact arrangement. In this embodiment, each terminal 10 is formed such that two wires are arranged one over another to be connected, and a housing 20 is so formed as to arrange wires in two vertical stages. The housing 20 for accommodating the terminals 10 includes a box-shaped lower casing 30 and an upper casing 40 for closing an opening in the upper surface of the lower casing 30. As shown in FIG. 1 or 2, the lower casing 30 has a bottom wall 31, left and right side walls 32. The front, rear and ceiling surfaces of the lower casing 30 are open in lateral and vertical directions. Three partition walls 33 are so formed as to define clearances corresponding to the width of the terminals 10. A total of four terminal chambers 34 are formed by the three partition walls 33 formed by the left and right side walls 32. The respective terminals 10 are accommodated in the four terminal chambers 34 such that the lower blade parts 12a and/or the lower blade portions 12a1 and the higher blade parts 12b and/or the higher blade portions 12b1 are located at the front and at the back, respectively and that the slits of the blade portions 12a, 12b are open upward. Each terminal 10 is fixed by fitting the opposite ends of the blade portions 12a, 12b into grooves formed at or in proximity of the opposite side walls of the corresponding terminal chamber 34. Wire retaining grooves 35 are formed on the bottom wall 31 by projections before and in conformity with the four terminal chambers 34. Linearly extending projections 35a are formed on the inner wall surfaces of the wire retaining grooves 35. The projections 35a cut in the insulation coatings of the wires so as to prevent the wires from coming out of the grooves 35. The grooves 35 and the lower blade portions 12b of the terminals 10 are at substantially the same height so that, when branch wires 50 are retained in the grooves 35, the leading ends of the branch wires 50 are pressed to be connected with the blade parts 12b and/or the blade portions 12b1 and linearly extend. The slits of the higher blade parts 12a and/or the higher blade portions 12a1 are located higher than those of the lower blade parts 12b and/or the lower blade portions 12b1 by about the thickness or diameter of one wire or more. Locking projections 32a are formed at the upper ends of the outer surfaces of the left and right side walls 32. The upper casing 40 for closing the opening in the upper surface of the lower casing 30 is formed with locking arms 41 for holding the upper ends of the left and right side walls 32. The locking arms 41 are formed with lock holes 41a engageable with the locking projections 32a. Two each of the locking projections 32a, the locking arms 41 and the lock holes 41a are arranged one in front of the other at the left and right side walls 32. As shown in FIG. 3, similar to the wire retaining grooves 35, four wire retaining grooves 42 are formed by projections on the inner surface of the upper casing 40 to be opposed to the lower casing 30. On the inner surfaces of the respective wire retaining grooves 42, there are also formed linearly extending projections 42a for cutting in the insulation coatings of the wires to prevent them from coming out of the grooves 42. For each wire, two wire retaining grooves 42 are formed at the front and rear sides. When the upper casing 40 closes the opening of the lower casing 30 while retaining main wires 60, the main wires 60 are in positions to be pressed against the higher blade parts 12a and/or the higher blade portions 12a1. The wire retaining grooves 42 are formed on particularly pillow-shaped stepped portions 43 which are slightly higher than the inner surface of the upper casing 40 so that the wires 60 can be easily pressed toward the lower casing 30. Each stepped portion 43 is formed with a laterally extending slit 43a into which the upper end of the blade part 12a and/or the blade portion 12a1 is substantially fittable. By fitting the upper ends of the blade parts 12a and/or the blade portions 12a1 into the slits 43a, the wires on the stepped portions 43 can be more easily pressed into the slits of the blade parts 12a and/or of the blade portions 12a1. Although the housing 20 is constructed by the lower casing 30 and the upper casing 40 in this embodiment, any housing may be used provided it can accommodate the terminals 10 having the blade parts 12a, 12b and/or the blade portions 12a1, 12b1 of different heights (or depths) or arranged at different heights and retain the wires 60, 50 such that they can be connected with the corresponding blade parts 12a, 12b and/or blade portions 12a1, 12b1. For example, a casing which can be opened and closed may be integrally formed, or the upper surface may be open. However, if the branch wires 50 and the main wires 60 are retained in specified positions of the lower casing 30 and the upper casing 40 which can be opened and closed, and the casings 30, 40 are fitted to press the wires 50, 60 against the blade parts 12a, 12b and/or the blade portions 12a1, 12b1 as in this embodiment, operability can be improved. Further, the wire retaining grooves 35, 42 may be suitably modified provided they can retain the wires in the specified positions. If the wire retaining grooves are arranged in a manner similar to that of a crankshaft instead of being linearly arranged, the wires can securely stay therein. Further, if the wire retaining grooves are arranged such that the wires are bent in a three-dimensional manner, the wires can more securely stay therein. In this embodiment, the branch wires 50 and the main wires 60 are arranged one over the other, and the branch wires 50 are pressed against the blade portions 12b by the main wires 60. Accordingly, a force to press the wires 50 against the blade parts 12b and/or the blade portions 12b1 is slightly taken up. The above ensures a compact arrangement. However, if the upper located main wires 60 are slightly curved with respect to a horizontal direction so as to project toward the branch wires 50, the projected portions of the main wires 60 press the branch wires 50 against the blade parts 12b and/or the blade portions 12b1, with the result that a loss of the pressing force can be made smaller. Further in this embodiment, the lower and upper casings 30 and 40 are locked by the locking projections 32a and the locking arm 41 on the left and right sides. If a recess 33a is formed substantially in the middle of the upper end of one partition wall 33 of the lower casing 30 and a pair of cover locks 44 engageable with the recess 33a are formed on the inner surface of the upper casing 40 as shown in FIG. 4, the upper and lower casings 30, 40 are locked not only at the opposite sides, but also in the middle, making themselves more unlikely to be detached. Next, how the embodiment thus constructed operates is described. The terminals 10 are accommodated in the corresponding terminal chambers 34 of the lower casing 30. As shown in FIG. 2, the leading end of the branch wire 50 is placed on the blade part 12b and/or the blade portion 12b1 held in the terminal chamber 34, and the branch wire 50 is pressed into the wire retaining groove 35. The projection 35a formed on the inner surfaces of the wire retaining groove 35 cut in or deforms the insulation coating of the branch wire 50 and retain the branch wire 50 when the branch wire 50 is pressed into the groove 35. The branch wires 50 are similarly set for the respective terminals 10. On the other hand, the main wire 60 is pressed into the wire retaining groove 42 in the upper casing 40. The projections 42a of the wire retaining grooves 42 cut in or deform the insulation coating of the main wire 60 in at least two positions at the front and rear sides, with the result that the main wire 60 is retained by the upper casing 40. E.g. four main wires 60 are retained in a similar manner. Thereafter, the upper casing 40 is so fitted as to close the opening in the upper surface of the lower casing 30. At this time, the main wires 60 retained by the upper casing 40 are pressed against the blade parts 12a and/or against the blade portions 12a1 of the terminals 10 held in the lower casing 30 and are also pressed against the branch wires 50 placed on the blade parts 12b and/or the blade portions 12b1. When the upper casing 40 is further pressed, the main wires 60 are pressed into the slits of the blade parts 12a and/or the blade portions 12a1 to be connected therewith, and the branch wires 50 are pressed into the slits of the blade parts 12b and/or the blade portions 12b1 via the main wires 60 to be connected therewith. As shown in FIG. 5, four each of the branch wires 50 and the main wires 60 are arranged in two vertical stages. As a whole, the wires are accommodated in a very compact manner. As described above, the terminals 10 are each formed such that two blade parts 12a, 12b and/or blade portions 12a1, 12b1 of different heights are aligned with respect to the longitudinal direction of the wires to be connected by bending the opposite ends of the strip 11 in the same direction by different lengths. In the lower casing 30 for accommodating the terminals 10, the branch wires 50 are placed on the lower blade parts 12b and/or on the lower blade portions 12b1. The upper casing 40 for covering the lower casing 30 retains the main wires 60 such that the main wires 60 face the lower blade part 12a and/or the lower blade portions 12a1 when the lower casing 30 is covered by the upper casing 40. When the upper casing 40 is fitted on the lower casing 30, the main wires 60 held by the upper casing 40 are pressed into the slits of the blade parts 12a and/or the blade portions 12a1 to be connected therewith, and press the branch wires 50 placed on the blade parts 12b and/or the blade portions 12b1 in the lower casing 30 into the slits of the blade parts 12b and/or the blade portions 12b1 so that the branch wires 50 are connected with the blade parts 12b and/or the blade portions 12b1. The connected wires 50, 60 are arranged in two vertical stages in a compact manner. In FIGS. 6 to 9, a terminal 110 is formed by bending a metal strip at a substantially right angle so as to have two surfaces perpendicular to each other. The respective surfaces are cut at a right angle from one longer edge of the terminal 110 to form slits 111a1, 112a1. These surfaces formed with slits 111a1, 112a1 act as blade parts 111, 112 and/or as blade portions 111a, 112a, wherein the blade parts 111, 112 comprise or include or carry the blade portions 111a, 112a. The edge of the terminal 110 where the slits 111a1, 112a1 are formed already has a steplike contour before the terminal 110 is bent. By forming the slits 111a1, 112a1 of the same depth, the blade parts 111, 112 and/or the blade portions 111a, 112a having different heights are formed. Although the terminal 110 has the two blade parts 111, 112 formed by bending the metal strip at right angles in this embodiment, it is sufficient to make the longitudinal directions of wires to be connected intersect. The number of blade portions and/or blade parts may be increased as in a terminal shown in FIGS. 10 and 11 which has three blade portions and/or blade parts arranged such that neighboring blade portions are at an angle of substantially 45°. Further, although the edge of terminal 110 where the slits 111a1, 112a1 are formed has a steplike contour in this embodiment, a parallelogrammatical or trapezoidal strip may be bent such that two smaller parallelogrammatical pieces intersect at different heights and the slits 111a1, 112a1 may be formed in the upper edges thereof. By having a steplike contour, the respective blade parts 111, 112 and/or blade portions 111a, 112a can be more clearly distinguished, and the wires can be more easily crossed. The shape of the slits formed in the blade parts 111, 112 and/or the blade portions 111a, 112a is not particularly specified, but may be suitably changed according to the kind of a wire core, i.e. whether the core is made of a single wire or a plurality of wires. In this embodiment, by using the metal strip having a steplike contour and forming the slits of the same depth, the blade parts 111, 112 and/or the blade portions 111a, 112a appeared to have different heights are formed. However, deep slits may be formed in the strip and the height of the actually used portion of the blade part and/or the blade portion may be changed by changing the depth by which the wire is pressed. A housing 120 as a first casing has a substantially square flat shape, and four each of first grooves 121 (121a to 121d) and second grooves 122 (122a to 122d) which intersect at right angles as in a checkerboard are formed in the upper surface of the housing 120. The first grooves 121a to 121d are continuous grooves crossing the housing 120 substantially in parallel. The second grooves 122a to 122d also cross the housing 120, but the bottom surfaces thereof are located higher than those of the first grooves 121a to 121d. Accordingly, the second grooves 122a to 122d are interrupted or crossed by the first grooves 121a to 121d. The first grooves 121a to 121d and the second grooves 122a to 122d intersect in 16 positions arranged in a manner similar to that of a 4×4 matrix. The terminals 110 are mounted at intersections preferably along one diagonal line. Specifically, the terminals 110 are pressed into rectangular walls 123a to 123d projecting from portions of the housing 120 other than the grooves 121, 122 such that the lower blade parts 111 and/or the lower blade portions 111a of the terminals 110 cross the first grooves 121 at substantially right angles and the higher blade parts 112 and/or the higher blade portions 112a cross the second grooves 122 at substantially right angles. How the terminal 110 is mounted is enlargedly shown in FIG. 13. In this embodiment, two groups of first grooves 121 (121a to 121d) and second grooves 122 (122a to 122d) intersecting at right angles are formed. However, the invention is not limited to this arrangement of grooves, but more groups of grooves may be formed provided they intersect in a manner similar to that of a network. For example, terminals having three blade parts and/or blade portions as shown in FIGS. 10 and 11 may be used together with a substantially hexagonal shaped housing formed with three groups of grooves as shown in FIG. 14. Further in this embodiment, the terminals 110 are mounted at those of the intersections arranged like a matrix which are located along one diagonal line. The terminals 110 may not necessarily be located on the diagonal line, but may be selectively mounted at other intersections. Although the depth of the first grooves 121a to 121d and the depth of the second grooves 122a to 122d are differed so that the wires can be arranged in a three-dimensional manner or on different planes in the embodiment, the depth of the grooves may need not necessarily be changed. However, by changing the depth of the grooves according to the wires to be intersected at the terminals 110, an operator can easily see wire arrangement positions and an upward or downward displacement of the wires during the arrangement can be prevented. Further, by forming wavy grooves instead of the linear grooves 121, 122, the wires can more securely stay in the grooves. In this embodiment, wedge-shaped projections 124a to 124d which project more as they extend more downward or which taper downwards are formed at the opposite edges of the openings of the grooves 121a to 121d at one side so as to prevent the wires from easily coming out of the grooves 121a to 121d. A cover 130 is adapted to cover an open upper surface of the housing 120 and is formed with linearly extending first projections 131 (131a to 131d) and second projections 132 (132a to 132d) in conformity with the first grooves 121a to 121d and the second grooves 122a to 122d, respectively. The second projections 132 substantially continuously extend, but the first projections 131 are interrupted or crossed by the lower first projections 131 so as to be pressed while straddling the crossing wires. Accordingly, the wires can be held on the second projections 132 while being tightly held between the interrupted portions of the first projections 131. Since the first projections 131a to 131d and the second projections 132a to 132d face the wires to be connected, portions thereof face the blade parts 111, 112 and/or the blade portions 111a, 112a of the terminals 110. In such portions of the first and second projections 131, 132, slots 133, 134 corresponding to the thickness of the terminals 110 are formed. Accordingly, when the cover 130 is fitted on the housing 120, the blade parts 111, 112 and/or the blade portions 111a, 112a of the terminals 110 are fitted into the slots 133, 134 and the wires are pressed downward at the opposite sides of the blade parts 111, 112 and/or blade portions 111a, 112a. Front and rear walls of the slots 133, 134 act as wire pressing portions in this embodiment. Although the cover 130 has a substantially square shape so as to correspond to the housing 120 in this embodiment, the shape thereof can be suitably changed according to the shape of the housing 120 in the case that the housing 120 is modified as described above. Further, although the linearly extending first and second projections 131, 132 are formed in conformity with the first and second grooves 121, 122 in order to more easily press the wires in this embodiment, ribs or struts may be formed in positions to project from the cover 130 to press the wires. Further, the wire pressing portions do not have to be slots 133, 134 into which the blade parts 111, 112 and/or the blade portions 111a, 112a are fittable, but can be anything provided they can come into contact with the wires before and after the blade parts 111, 112 and/or the blade portions 111a, 112a and press them. In this embodiment, wedge-shaped projections 135a to 135d, 136a to 136d which project more as they extend more downward or which taper downwards are formed at the opposite edges of the openings of the projections 132 at both sides so that the wires securely stay on the projections 132. The housing 120 and the cover 130 are formed with recesses and projections 125, 137 on their surfaces which come into sliding contact with each other when the housing 120 and the cover 130 are fitted, and can be locked by engaging the recesses and projections 125, 137 (see FIGS. 15 to 18). Next, how the embodiment thus constructed operates is described. The housing 120 is placed such that the grooves 121, 122 are found in the upper surface thereof, and branch wires 141a to 141d to be connected are pressed into the first grooves 121. The cover 130 is placed such that the projections 131, 132 are found in the upper surface thereof, and main wires 142a to 142d to be connected are held on the second projections 132a to 132d. Since the terminals 110 are mounted at the intersections of the grooves 121, 122 in the housing 120, each branch wire 141 crosses the blade part 111 and/or the blade portion 111a of one terminal 110 when being pressed into the groove 121. The branch wires 141 are merely so placed as to cross the blade parts 111 and/or the blade portions 111a without being pressed into the slits 111a of the blade parts 111, and are locked in the grooves 121 by the projections 124a to 124d at the openings at one side so as not to be displaced. In the cover 130, the main wires 142a to 142d are locked by the projections 135a to 135d, 136a to 136d at the openings at both sides so as not to fall down even when the cover 130 is turned upside down. After e.g. four each of the branch wires 141 and the main wires 142 are accommodated in the housing 120 and the cover 130, respectively, the cover 130 is turned upside down and fitted on the upper surface of the housing 120. Then, the second projections 132a to 132d face and press the main wires 142 into the second grooves 122, and the first projections 131a to 131d face and press the lower located branch wires 141 into the first. grooves 121 while straddling the main wires 142. Further, the slots 133, 134 formed in the projections 131, 132 press the branch and main wires 141, 142 crossing over the blade parts 111, 112 and/or the blade portions 111a, 112a particularly in a curved manner into the slits 111a, 112a of the blade parts 111, 112 and/or the blade portions 111a, 112a so as to connect the wires 141, 142 with the blade parts 111, 112 and/or the blade portions 111a, 112a, respectively. When the cover 130 is fully fitted on the housing 120, the cover 130 and the housing 120 are locked by engagement of the projections and recesses 137, 125 and the connected wires are tightly held by the wedge-shaped projections 124, 135, 136 so as not to come out. FIG. 19 shows how the wires are connected with the terminal 110. Although the housing 120 and the cover 130 are assembled after the branch wires 141 and the main wires 142 are separately accommodated therein, the cover 130 may be fitted on the housing 120 after the branch wires 141 and the main wires 142 are accommodated in the housing 120. By separately forming parts for accommodating the branch wires 141 and the main wires 142 as in this embodiment, the operation can be performed in different places and there is no likelihood that the wires are wrongly arranged. As described above, in the housing 120 as a first casing, the parallel first grooves 121a to 121d and the parallel second grooves 122a to 122d are so formed as to intersect; the terminals 110 having the blade parts 111, 112 and/or the blade portions 111a, 112a of different heights or depths are pressed into the rectangular walls 123a to 123d at the intersections; and the branch wires 141 are accommodated in the grooves 121. On the other hand, in the cover 130 as a second casing, the first projections 131a to 131d and the second projections 132a to 132d to be opposed to the grooves 121, 122 are formed. The main wires 142 are held on the projections 132. When the cover 130 is fitted to cover the housing 120, the first projections 131 press the branch wires 141 into the grooves 121; the second projections 132 press the main wires 142 into the grooves 122; and the respective wires 141, 142 are pressed by the front and rear walls of the slots 133, 132 into the slits 111a1, 112a1 of the blade parts 111, 112 and/or the blade portions 111a, 112a to be connected with the blade parts 111, 112 and/or the blade portions 111a, 112a. Since the wires to be connected can be arranged on the upper surfaces of the housing 120 and the cover 130, operability can be improved. In FIG. 20, a terminal 210 is formed by bending a strip 211 having obliquely extending opposite ends or ends extending at an angle with respect to a longitudinal direction of the strip as shown in FIG. 21 where slits 212a1, 213a1 are formed in the ends along a lengthwise direction thereof or from end faces toward the opposite sides substantially in the same direction by different lengths. Since the opposite ends of the terminal 210 has different lengths, the bent opposite ends form a lower blade part 212 and/or a lower blade portion 212a and a higher blade part 213 and/or a higher blade portion 213a, respectively. This height difference substantially corresponds to the thickness of wires to be connected. Since the wires are basically arranged in two vertical stages or planes, the heights of the blade parts 212, 213 and/or the blade portions 212a, 213a are differed by at least the thickness of the wires. However, the height difference may be larger than the thickness of the wires. Since the blade parts 212, 213 and/or the blade portions 212a, 213a obliquely extend at the opposite ends of the strip, after being bent, they are parallel to each other along forward and backward directions and are slightly displaced along a lateral direction. A displacement distance is determined as follows. When a plurality of terminals 210 are arranged side by side and oriented in the same direction as shown in FIG. 21, the respective blade parts 212, 213 and/or the respective blade portions 212a, 213a are aligned along the lateral direction and the slits 212a, 213a are displaced in the corresponding blade parts 212, 213 and/or blade portions 212a, 213a. In other words, the slits 212a, 213a are alternately and equally arranged at the front and rear sides. Although the blade parts 212, 213 and/or the blade portions 212a, 213a of different heights or depths are formed using the strips 211 having obliquely extending opposite ends in this embodiment, the opposite ends may not necessarily be obliquely displaced. It is sufficient for the opposite ends to be displaced along the forward and backward directions. Accordingly, as shown in FIG. 22, lower and higher blade parts 215, 216 and/or the lower and higher blade portions 215a, 216a may be formed by forming slits 215a, 216a in the opposite ends of a linear strip 214 and bending the opposite ends substantially at right angles in the same direction by different lengths. Alternatively, as shown in FIG. 23, slits 218a, 219a extending in a direction normal to the length of a strip 217 may be formed in blade parts 218, 219 and/or in blade portions 218a, 219a before the opposite ends of the strip 217 are bent. In this way, the terminal may be suitably modified. Further, the blade parts may not necessarily be formed by bending the opposite ends of a strip. For example, blade parts and/or blade portions having different heights may be electrically connected by a wire or the like. A first casing or housing 220 includes a terminal fixing portion 222 for fixing the terminals 210 on the upper surface of a substantially rectangular base 221, and a wire support portion 223 formed at its longer side for supporting branch wires 230. The terminal fixing portion 222 includes two front and rear wall portions 222a, 222b of different heights projecting in correspondence with the front and rear blade parts 212, 213 and/or the front and rear blade portions 212a, 213a of the terminals 210. Recesses 222a1, 222b1 into which the blade parts 212, 213 and/or the blade portions 212a, 213a are insertable are formed in the wall portions 222a, 222b, respectively. As the corresponding blade parts 212, 213 and/or blade portions 212a, 213a are displaced along the lateral direction, the recesses 222a1, 222b1 are also displaced along the lateral direction. E.g. four terminals 210 are mountable in the first casing 220 from above. Further, in the inner surfaces of the recesses 222a1, 222b1 are formed slots into which the edges of the blade parts 212, 213 and/or the blade portions 212a, 213a are inserted. FIG. 24 shows the first casing 220 in which the terminals 210 are mounted in the fixing portion 222. Although the terminals 210 are supported in the recesses 222a1, 222b1 formed in two wall portions 222a, 222b in this embodiment, a support construction for the terminals 210 is not particularly limited to this. The support construction may have any suitable shape. For example, a portion of the terminal 210 connecting the blade parts 212, 213 and/or the blade portions 212a, 213a may be secured to the base 221. The support construction may be suitably modified so as to conform to the modification of the terminals- 210 as described above. In the case that at least the lower wall portion 222a and recesses 222a1 are provided, the upper end of the wall portion 222a faces main wires 250 to be retained by a second casing 240 as described later so that the main wires 250 can be stably retained. The wire support portion 223 formed at the edge of the base 221 includes four forked portions 223a extending in parallel with the base 221. The branch wires 230 are supported by being inserted into the respective forked portions 223a. In this case, the branch wires 230 hang downward from the base 221 as shown in FIG. 25. The second casing 240 is fitted with the first casing 220 to form one casing. As shown in FIG. 26, the second casing 240 includes a base 241 for covering an upper portion of the first casing 220 and a wire support portion 242 for retaining main wires 250 on the base 241. Similar to the fixing portion 222, the wire support portion 242 includes two rows of wall portions 242a, 242b. Four recesses 242a1 and 242b1 are formed in the wall portion 242a and 242b. The corresponding recesses 242a1, 242b are linearly arranged along an axial direction, and small projections 242a2, 242b2 are formed on the opposing inner surfaces of the recesses 242a1, 242b1 so that the wires pressed into the recesses 242a1, 242b1 are locked therein. Since the corresponding recesses 242a2, 242b2 formed in the front and rear wall portions 242a, 242b are linearly arranged unlike the laterally displaced recesses 222a1, 222b1 formed in the front and rear wall portions 222a, 222b of the first casing 220, when the first and second casings 220, 240 are fitted while positioning the recesses 222b1, 242b1, the recesses 222a1, 242a1 are displaced from each other to be covered by the upper ends of the mating wall portions 242a, 222a as shown in FIG. 27. At this time, the upper end of the wall portion 242a of the second casing 240 acts as projections 242a3 to be opposed to the lower blade parts 212 and/or the lower blade portions 212a held by the first casing 220. Although the two wall portions 242a, 242b are formed one in front of the other in this embodiment, the second casing 240 may be suitably modified provided it is formed with the projections 242a3 to be opposed to the lower blade parts 212 and/or the lower blade portions 212a when the second casing 240 is fitted on the first casing 220. Further, the positions of the projections 242a3 may be suitably changed according to the arrangement of the branch wires 230 and the main wires 250. The main wires 250 are linearly held in this embodiment. However, as shown in FIG. 28, they may be held while being bent as with the terminals 210 described above. In such a case as well, it is sufficient to form projections to be opposed to the lower blade portions with which the branch wires 230 are to be connected. As is clear from the above example, it is sufficient to arrange the branch wires 230 and the main wires 250 obliquely to each other. To this end, an arrangement may be such as in FIG. 21 where the intermediate portions of the terminals 210 obliquely extend or such as in FIG. 22 where the terminals 210 themselves are obliquely arranged. Loop- or frame-shaped locking arms 243 stand upright at shorter edges of the base 241 of the second casing 240, and wedge-shaped locking projections 224 engageable with the locking arms 243 are formed on the outer surfaces of the wall portions 222a, 222b of the first casing 220. Accordingly, when the first and second casings 220, 240 are moved closer to each other, the locking arms 243 and the locking projections 224 are lockingly engaged. Although the casings 220, 240 are locked by the locking arms 243 and the locking projections 224 in this embodiment, other general locking constructions may also be adopted. Next, how the embodiment thus constructed operates is described. The terminals 210 are formed by bending the opposite ends of the strips 211 to form the blade parts 212, 213 carrying the blade portions 212a, 213a, the blade parts 212, 213 and/or the blade portions 212a, 213a having different heights at the opposite ends. The terminal 210 is mounted in the casing 220 by inserting the lower blade portion 212 into the recess 222a1 of the wall portion 222a while inserting the higher blade portion 213 into the recess 222b2 of the wall portion 222b. After mounting four terminals 210 in this manner, end portions of four branch wires 230 are pressed into the forked portions 223a formed at the wire support portion 223 while being placed on the lower blade parts 212 and/or the lower blade portions 212a held in the recesses 222a1. On the other hand, in the second casing 240, the main wires 250 are pressed into the four recesses 242a1, 242b1 formed in the two front and rear wall portions 242a, 242b. When the first casing 220 and the second casing 240 retaining the branch wires 230 and the main wires 250 are fitted, the recesses 222b1 of the first casing 220 face the recesses 242b1 of the second casing 240. Accordingly, the main wires 250 are pressed against the higher blade parts 213 and/or the higher blade portions 213a of the terminals 210 to be connected therewith. On the other hand, the projections 242a3 which are projected portions of the wall portion 242a of the second casing 220 face the recesses 222a1 of the first casing 220, and press the ends of the branch wires 230 placed on the lower blade parts 212 and/or the lower blade portions 212a held in the recesses 222a1 to connect the branch wires 230 with the blade parts 212 and/or the blade portions 212a. Immediately after the completion of the connection, the locking arms 243 of the second casing 240 are engaged with the locking projections 224 of the first casing 220 to lock the casings 220, 240. This state is shown in FIG. 29. As described above, by fitting the first and second casing 220, 240, the branch wires 230 and the main wires 250 face the blade parts 212, 213 and/or the blade portions 212a, 213a of different heights while being arranged in two vertical stages. Simultaneously, the branch wires 230 and the main wires 250 are pressed against the blade parts 212, 213 and/or the blade portions 212a, 213a by the mating casing 240, 220 of those retaining the wires 230 and 250, and connected with the blade parts 212, 213 and/or the blade portions 212, 213, respectively. Accordingly, as compared with the case where the branch wires 230 and the main wires 250 are arranged side by side, the wires can be arranged in a more compact manner. If the wires are merely arranged in two vertical stages, the branch wires 230 and the main wires 250 are pressed against the lower blade parts 212 and/or the lower blade portions 212a one over the other. This may make it difficult to connect the wires with the blade portions because the wires have elasticity. In this embodiment, since the projections 242a3 to be opposed to the lower blade portions 212 are formed to press the branch wires 230 against the blade portions 212, the connection can be easily made. The cramping connector is made more compact by differing the heights of the blade parts and/or blade portions of the terminals in the foregoing embodiments. However, in an embodiment shown in FIGS. 30 to 36, blade parts 362, 363 having (or including or carrying) blade portions 362a, 363a of each terminal 360 are shifted only along forward and backward directions and have the same height. In (or on or at) the blade parts 362, 363 and/or in the blade portions 362a, 363a are formed slits 362a1, 363a1. The terminal 360 is basically formed similar to the previous terminals except that the heights of the blade parts 362, 363 and/or the blade portions 362a, 363a are same. The front and rear blade parts 362, 363 and/or the front and rear blade portions 362a, 363a are shifted along a lateral direction while being opposed in parallel, and an obliquely extending strip 361 connects the blade parts 362, 363. It should be appreciated that the invention is not necessarily limited to this embodiment since the blade parts 362, 363 and/or the blade portions 362a, 363a only need to be shifted along the forward and backward directions. Thus, the terminal 360 may be formed similar to the previous ones. The terminals 360 are accommodated in a housing including a pair of casings: a lower casing 370 and an upper casing 380. Specifically, recesses 371a used to accommodate the terminals 360 are formed in an inner bottom surface 371 of the lower casing 370 as shown in FIG. 31, and one terminal 360 is mounted and held in each recess 371a as shown in FIG. 32. Four obliquely extending recesses 371a are formed. Accordingly, the blade parts 362, 363 and/or the blade portions 362a, 363a of the accommodated terminals 360 are alternately arranged in front and rear rows. In other words, a blade part 363 and/or a blade portion 363a is located between two adjacent blade parts 362 and/or blade portions 362a, and a blade part 362 and/or a blade portion-362a is located between two adjacent blade parts 363 and/or blade portions 363a. By alternately arranging the blade parts 362, 362 and/or the blade portions 362a, 363a in the front and rear rows along the lateral direction, the cramping connector can be made narrower as compared with the one in which the blade parts and/or the blade portions are arranged side by side in one row. Comb-like ribs 372 (372a, 372b) and 373 (373a, 373b) for guiding branch wires 390 and main wires 400 into the respective blade parts 362, 363 and/or blade portions 362a, 363a are formed in the casing 370. The branch and main wires 390, 400 are alternately inserted between adjacent ribs 372, but only the main wires 400 are inserted between adjacent ribs 373 since the leading ends of the branch wires 390 are pressed into recesses 371c formed in the inner bottom surface 371 as shown in FIGS. 33 and 34. The terminals 360 are mounted such that the blade parts 362, 363 and/or the blade portions 362a, 363a thereof are substantially normal to the branch and main wires 390, 400 inserted between the ribs 372 and between the ribs 373. At portions of the respective ribs 372a, 373a where the branch and main wires 390, 400 are inserted, there are formed projections 372a1, 373a1 for preventing the wires 390, 400 from coming out. The branch and- main wires 390, 400 inserted between the ribs 372 and between the ribs 373 after the terminals 360 are mounted in the casing 370 are partly locked, i.e. being prevented from coming out. Further, a line of projection 373b1 is formed on one side surface of each rib 373b. The projections 373b1 cut in and/or deform the insulation coating of the branch wires 390 from opposite sides so as to prevent the branch wires 390 from coming out. The branch wires 390 are bent substantially at 90° after having their leading ends pressed into the recesses 371c, and further held between the projections 373b1. Thus, the branch wires 390 cannot easily come out. On the other hand, the upper casing 380 is so formed as to cover the upper surface of the lower casing 370. As shown in FIG. 35, wire pressing portions 381, 382 in the form of projections are so formed on the rear surface of the upper casing 380 as to correspond to the respective blade parts 362, 363 and/or blade portions 362a, 363a. The end face of each of the wire pressing portions 381, 382 has a substantially concave shape so that the wire pressing portion 381 or 382 can press the branch wire 390 or main wire 400 down while holding it. Further, each of the wire pressing portions 381, 382 includes preferably two pressing portions 381a, 381b (or 382a, 382b) so that the wire 390 or 400 can be pressed down preferably at the opposite sides of the plate-like blade parts 362 or 363 and/or blade portions 362a or 363a. Thus, when the upper casing 380 is mounted and pressed after the branch and main wires 390, 400 are partly locked on the casing 370, each wire pressing portion 381 presses the branch wire 390 into the slit of the corresponding blade part 362 and/or in the blade portion 362a, thereby establishing a contact between the branch wire 390 and the blade part 362 and/or the blade portion 362a, whereas each wire pressing portion 382 presses the main wire 400 into the slit of the corresponding blade part 363 and/or blade portion 363a, thereby establishing a contact between the main wire 400 and the blade part 363 and/or the blade portion 363a. Engaging projections 375a, 375b are formed one above the other on each of side walls 374 of the lower casing 370 where the ribs 372, 373 are not formed, and an engaging recess 383a is formed in an inner surface of each corresponding side wall 383 of the upper casing 380. As the upper casing 380 is mounted, the upper engaging projections 375a are first engaged with the edges of the recesses 383a (partial engagement). When the upper casing 380 is further pressed down, the lower engaging projections 375b are engaged with the edges of the recesses 383a (full engagement). In this way, as shown in FIG. 36, the lower and upper casings 370, 380 are assembled, and the branch and main wires 390, 400 come out of the cramping connector while densely being arranged. Accordingly, the cramping connector is, as a whole, narrower. A pressing device 410 (FIG. 30) such as pliers is used to press the upper casing 380 to fit it to the lower casing 370. In the case of the embodiment shown in FIGS. 30 to 36, a fittable portion 384 in the form of recesses and projections conforming to the shape of a pressing surface of the pressing device 410 is formed on the bottom surface (not shown) of the lower casing 370 and on the upper surface of the upper casing 380. When the lower and upper casings 370, 380 are pinched by the pressing device 410 , the recesses and projections formed on the pressing surfaces of the pressing device 410 are fitted to the fittable portions 384 formed on the bottom surface of the lower casing 370 and on the upper surface of the upper casing 380, with the result that the projections are fitted into the corresponding recesses. Accordingly, the assembling of the lower and upper casings 370, 380 can be completed without any displacement in the lateral direction. The fittable portion 384 needs not have a shape as shown in FIG. 30 provided it prevents a displacement in a direction substantially normal to a pressing direction in which the lower and upper casings 370, 380 are pressed by the pressing device 410. For example, the pressing device 410 may have concave surfaces while the lower and upper casings 370, 380 may have a convex bottom surface and a convex upper surface, respectively. Conversely, the pressing device 410 may have convex surfaces while the lower and upper casings 370, 380 may have a concave bottom surface and a concave upper surface, respectively. The corresponding concave and convex shapes need not be constantly in contact. Portions to be pressed may gradually change as the pressing surfaces are moved, while making an arcuate trace, to press the lower and upper casings 370, 380 as with pliers. It is not necessary to form a recess or projection at both the lower casing 370 and the upper casing 380. If a recess or projection in conformity with the shape of the pressing surface is formed at least at one of the lower and upper casings 370, 380, a lateral displacement can be prevented, thereby improving operability. As described above, by assembling the first casing and the second casing , the branch wires and the main wires are so arranged one above the other as to face the blade parts and/or blade portions having different heights. The branch wires and the main wires are pressed against the blade parts and/or the blade portions by the mating casings of the casings holding them, and connected therewith. Accordingly, as compared with the case where the branch wires and the main wires are arranged side by side, the cramping connector can be made more compact. If the branch wires and the main wires are simply arranged in two stages one above the other, it may be difficult to connect the wires with the lower blade part and/or the lower blade portions due to the elasticity of the wires. However, since the projections are so formed as to face the lower blade parts and/or the lower blade portions and to press the wires against the lower blade parts and/or the lower blade portions , the connection are easily attainable. Even with the terminals 360 having the blade parts and/or the blade portions 362, 363 only shifted along the forward and backward directions, the cramping connector can be made more compact as compared with the case where the blade parts and/or the blade portions are arranged side by side in a row although it is not as compact as in the case where the branch and main wires are arranged in two stages one above the other. LIST OF REFERENCE NUMERALS 10 ... Terminal 12a ... Blade part 12b ... Blade part 12a1 ... Blade portion 12b1 ... Blade portion 20 ... Housing 30 ... Lower Casing 34 ... Terminal Chamber 35 ... Wire Retaining Groove 40 ... Upper Casing 42 ... Wire Retaining Groove 50 ... Branch Wire 60 ... Main Wire 110 ... Terminal 111, 112 ... Blade part 111a, 112a ... Blade Portion 111a1, 112a1 ... Slit 120 ... Housing 121 (121a to 121d) ... First Groove 122 (122a to 122d) ... Second Groove 130 ... Cover 131 (131a to 131d) ... First Projection 132 (132a to 132d) ... Second Projection 133, 134 ... Slot 210 ... Terminal 211, 214, 217 ... Strip 212, 213, 215, 216, 218, 219 ... Blade part 212a, 213a, 215a, 216a, 218a, 219a ... Blade Portion 212a1, 213a1, 215a1, 216a1, 218a1, 219a1 ... Slit 220 ... First Casing 221 ... Base 222 ... Terminal Fixing Portion 230 ... Branch Wire 240 ... Second Casing 241 ... Base 242 ... Wire Support Portion 242a, 242b ... Wall Portion 242a3 ... Projection 250 ... Main Wire 360 ... Terminal 361 ... Strip 362, 363 ... Blade part 362a, 363a ... Blade Portion 362a1, 363a1 ... Slit 390 ... Branch Wire 400 ... Main Wire 370 ... Lower Casing 380 ... Upper Casing

Claims: A cramping connector, comprising: at least one terminal (10; 110; 210; 360) having a plurality of blade portions (12a1, 12b1; 111a, 112a; 212a,213a; 215a, 216a; 218a, 219a), and a housing (30, 40; 120, 130; 220; 240; 370, 380) for retaining the terminal (10; 110; 210; 360) and for positioning a plurality of wires (50, 60; 141, 142; 230, 250; 390, 400) one over the other such that the wires (50, 60; 141, 142; 230, 250; 390, 400) are to be pressed into the corresponding blade portions (12a1, 12b1; 111a, 112a; 212a, 213a; 215a, 216a; 218a, 219a), when the housing (30, 40; 120, 130; 220; 240; 370, 380) is formed or assembled, the plurality of blade portions (12a1, 12b1; 111a, 112a; 212a, 213a; 215a, 216a; 218a, 219a; 362a, 363a) being arranged at or having same or different heights, wherein the housing (30, 40; 120, 130; 220; 240; 370, 380) comprises wire retainers (34; 42; 124; 135; 223; 242; 372) for fixedly retaining the plurality of wires (50, 60; 141, 142; 230, 250; 390, 400) on the housing and positioning them with respect to the corresponding blade portions (12a1,12b1; 111a, 112a; 212a, 213a; 215a, 216a; 218a, 219a). A cramping connector according to claim 1, wherein the housing comprises at least a pair of first (30; 120; 220; 370) and second (40; 130; 240; 380) casings and wherein the wire retainers (34; 42; 124; 135; 223; 242; 372) comprise first wire retainers (34; 124; 223; 372) provided on the first casing (30; 120; 220; 370) and second retainers (42; 135; 242) provided on the second casing (40; 130; 240; 380). A cramping connector according to claim 2, wherein first wires (50; 141; 230; 390) can be retained on the first casing (30; 120; 220; 370) by the first wire retainers (34; 124; 223; 372) and second wires (60; 142; 250; 400) can be retained on the second casing (40; 130; 240; 380) by the second retainers (42; 135; 242), the first wires (50; 141; 230; 390) and the second wires (60; 142; 250; 400) being arranged one over the other when the first and second casings (30, 40; 120, 130; 220; 240; 370, 380) are mated or connected. A cramping connector according to one or more of the preceding claims, wherein the plurality of wires (50, 60; 141, 142; 230, 250; 390, 400) can be positioned such that, ends of first or branch wires (50; 141; 230; 390) of the plurality of wires face the blade portions (12a1, 12b1; 111a, 112a; 212a, 213a; 215a, 216a; 218a, 219a) at one side and that second or main wires (60; 142; 250; 400) of the plurality of wires are to be inserted between the blade portions (12a1, 12b1; 111a, 112a; 212a, 213a; 215a, 216a; 218a, 219a) at the one side and face the blade portions (12a1, 12b1; 111a, 112a; 212a, 213a; 215a, 216a; 218a, 219a) at the other side, wherein the respective wires (50, 60; 141, 142; 230, 250; 390, 400) can be pressed into the corresponding blade portions (12a1, 12b1; 111a, 112a; 212a, 213a; 215a, 216a; 218a, 219a) when the housing, in particular when the first and second casings is/are assembled. A cramping connector according to one or more of the preceding claims, wherein the housing (120; 130) comprises first grooves (121) for accommodating wires (141) to be connected with first blade portions (111a) having substantially the same height, the first grooves (121) intersecting under an angle between 0° and 180°, preferably about 45°, 60°, 90°, 120° and/or 135°, with at least second grooves (122) for wires (142) to be connected with second blade portions (112a) having one or more heights different than the first grooves (121), the terminals (110) being particularly mounted at the intersections of the grooves (121, 122), and/or wherein the housing (110; 380) comprises wire pressing portions (112a, 112b; 381) which come into contact with the wires (142, 141; 390, 400) so as to press the wires (142, 141; 390, 400) into the blade portions (111a, 112a; 362a, 363a). A cramping connector according to one or more of the preceding claims, wherein the blade portions (212a, 213a; 215a, 216a; 218a, 219a; 362a, 363a) are obliquely arranged in the housing (220, 240; 370, 380). A cramping connector according to one or more of the preceding claims, wherein the blade portions (12a1, 12b1; 111a, 112a; 212a, 213a; 215a, 216a; 218a, 219a; 362a, 363a) are shifted along a longitudinal direction. A cramping connector according to one or more of the preceding claims, wherein the blade portions (12a1, 12b1; 212a, 213a; 215a, 216a; 218a, 219a; 362a, 363a) extend in substantially a same direction. A cramping connector according to one or more of the preceding claims, wherein the blade portions (111a, 112a) are arranged at an angle, in particular substantially normal with respect to each other.

Inventors: CHISHIMA MASAMITSU, SEKO SATOMI, CHISHIMA, MASAMITSU, SEKO, SATOMI
Applicants: SUMITOMO WIRING SYSTEMS, SUMITOMO WIRING SYSTEMS, LTD.
Application year: 1996
Main classification: H01R4
IPC codes: H01R4