INSTRUMENT FOR ASSEMBLING BOARD-SHAPED BODIES

Abstract: An instrument for assembling (1) two board-shaped bodies, including an engagement tool (3) adapted to be driven into an opening in one board-shaped body, and a fixing tool (5) adapted to be driven into an opening in the other board-shaped body. The engagement tool (3) includes an annular engagement member (31) having a radially outwardly projecting engagement portion provided with an engagement pawl (35a) adjacent the tip thereof, and a rotary cam or eccentric which is rotatably positioned within the annular member to effect radial displacement of the pawl (35a). The engagement tool (3) also includes an annular housing which accommodates therein the annular engagement member, the housing having stops for controlling the rotation of the cam to a predetermined angle, and having an outer peripheral structure which permits it to fixingly engage the one board-shaped body. The fixing tool (5) has an insertion hole (52) into which the engagement portion is inserted.

Description: The invention relates to an apparatus according to the preamble of claim 1. Such an apparatus is known from AT-B-384 469, wherein the casing consists of two pieces and has an oblong shape. The engagement member is plate-like and has an oblong opening into which the rotary member is inserted. This rotary member is provided with a radially projecting protrusion which cooperates with a tongue provided on the engagement member in such a way that the pawl of the engagement member is disengaged from the engagement portion of the fixing fitting as soon as the protrusion pushes the engagement member down via the tongue. It is the object of the invention to provide an apparatus of the above-mentioned kind which is capable of firmly assembling board-shaped bodies by a compact structure and which can be handled easily. This object is achieved according to the invention by the features in the characterizing part of claim 1. When the engagement fitting is first driven into one board-shaped body, the stepped grooves on the outer periphery of the case bite into the one board-shaped body, thereby firmly fixing the engagement member in place. When the fixing fitting is driven into the other board shaped body, the slip-off prevention member and stepped grooves of the fixing fitting bite into the other board-shaped body, thereby firmly fixing the fixing member in place. Subsequently, the engagement member of the engagement fitting is inserted into the insertion hole of the fixing fitting. With this condition, the rotary member is rotated through a predetermined angle. During this rotation, the rotary member moves the annular portion of the engagement member in its engagement direction so as to bring the engagement pawl of the engagement member into engagement with the engagement pin. In consequence, the two board-shaped bodies are firmly assembled. The drawings illustrate a preferred embodiment of an instrument for assembling board-shaped bodies in accordance with the present invention, wherein: Figure 1 is a perspective view showing the instrument for assembling board-shaped bodies; Figure 2 is an exploded perspective view of an engagement member; Figure 3A is a plan view of a rotor portion; Figure 3B is a perspective view of the rotor portion; Figure 4 is an explanatory view showing an engagement fitting, with the rotor portion removed; Figure 5 is a sectional view taken along the line A-A shown in Figure 4; Figure 6 is a plan view of a fixing fitting; Figure 7 is a side view of the same; Figure 8 is a bottom view of the same; Figure 9 is a plan view showing an invertedly-bent spring; Figure 10 is a side view of the same; Figure 11 is an explanatory view showing an initial state of engagement between the engagement tool and the fixing fitting; and Figure 12 is an explanatory view showing a state of engagement between the engagement fitting and the fixing fitting. DETAILED DESCRIPTION As shown in Figure 1, an instrument 1 for assembling (i.e. joining) two board-shaped bodies comprises an engagement fitting 3 and a fixing fitting 5. Referring to Figure 2, the engagement fitting 3 will be first described. The engagement fitting 3 comprises an engagement member 31, a rotary member 32, and a case 33 accommodating the engagement member 31 and the rotary member 32. The engagement member 31 is loosely fitted within the case 33, and the rotary member 32 is fitted inside the engagement member 31. The engagement member 31 comprises an engagement portion 35 and an annular portion 36. A recess 36a is formed in the upper surface of the annular portion 36 through a central angle of about 74 degrees. A peripheral rib-like wall 36b projects outwardly from the bottom surface of the annular portion 36. The peripheral wall 36b is notched through a central angle of about 100 degrees to form a notched portion 36c. The engagement portion 35 is normally formed on the outer peripheral surface of the annular portion 36 so as to project radially outwardly therefrom, and it has its tip formed into a hook-shape to provide an engagement pawl 35a. The rotary member 32 comprises a rotor portion 39 at one end, an intermediate cam portion 41, and a rotation hub 43 at the other end. A wrench hole 45 having the shape of a hexagonal prism longitudinally coaxially penetrates the rotary member 32. As shown in Figures 3A and 3B, a radial projection 41a is formed on the outer periphery of the cam portion 41, the projection 41a being located so as to be positioned within the above-mentioned notched portion 36c of the annular portion 36. A recess 41b is formed in the upper surface of the cam portion 41 over about one half of the circumference, while, in the other half of the circumference, two ridges (i.e. detents) 41c and 41d are formed in such a manner as to form a central angle of about 108 degrees therebetween with respect to the axial center O₁ of the rotation-hub 43. A further small ridge or detent 41e is formed at the middle angularly between the ridges 41c and 41d. The axial center O₂ of the cylindrical-shaped cam portion 41 is radially shifted (i.e. eccentric) from the axial center O₁ of the rotor 39 and hub 43 by a predetermined distance d. As shown in Figure 2, the case or housing 33 comprises a top plate 46, and a circumferential sleevelike wall 47 formed on and projecting downwardly from the lower surface of the top plate 46. An axial hole 46a is formed through the center of the portion of the top plate 46 so as to be coaxially aligned with the cylindrical wall 47 (this wall 47 rotatably supports the rotor portion 39). A substantially fan-shaped projection (i.e., a stop) 46b is formed adjacent the axial hole 46a through a central angle of about 60 degrees and projects radially thereof. In additional to the projection 46b, three detent grooves 46c, 46d, 46e, as well as a small groove 46f are formed in the bottom surface of the plate 46. The grooves 46c, 46d, and 46e are disposed in such a manner as to form central angles of about 108 degrees therebetween with respect to the center of the axial hole 46a, while the small groove 46e is disposed at the middle between the grooves 46c and 46d. The grooves project radially outwardly away from the hole 46a. The ridges 41c and 41d of the rotary member 32, described above, fit into these grooves 46c, 46d, and 46e so as to enable the determination of an engagement lock position and an engagement release position, as described later. The small ridge 41e fits into the small groove 46f so as to enable the determination of an engagement preparation position. Stepped grooves 47a are formed in the outer wall of the circumferential wall 47. A part of the circumferential wall 47 is notched at 48 for permitting the projection 35 to extend therethrough, and a position-determining projection 49, which is used to bring the engagement fitting 3 into engagement with the fixing fitting 5, is formed in the vicinity of the notch 48 and projects radially outwardly from the wall 47. When the above-described engagement-member 31, rotary member 32, and case 33 are integrated, as shown in Figures 4 and 5, the axial center O₁ of the rotation hub 43 and axial hole 46a is radially spaced from the axial center O₂ of the cam portion 41 by the predetermined distance d and, simultaneously, the annular portion 36 is accommodated within the case 33 with a certain play. Therefore, when the rotary member 32 rotates in the counterclockwise direction as viewed in Figure 4, the cam portion 41 rotates in such a manner that the outer peripheral surface of the cam portion 41 slides on and presses against the inner peripheral surface of the annular portion 36, thereby causing the engagement member 31 to move in the direction of an arrow A. The engagement portion 35 is urged by a ring-shaped spring 37 in the counterclockwise direction as viewed in Figure 4. This spring 37 is anchored at one end to the case 33, and at its other end to the engagement member 31. Since the recess 41b formed in the upper surface of the cam portion 41 registers with the projection 46b of the case 33, the rotation of the cam portion 41 stops where the edge of the recess 41b abuts against the projection 46b, in either the clockwise or counterclockwise direction. In addition, since the recess 36a of the annular portion 36 also registers with the projection 46b of the case 33, the rotation of the annular portion 36 stops where the edge of the recess 36a abuts against the projection 46b, in either the clockwise or counterclockwise direction as viewed in the figure. Next, the fixing fitting 5 will be described. As shown in Figures 6 to 8, the fixing fitting 5 comprises a position-determining plate 50 and a cylindrical driving member 51 connected to the position-determining plate 50 through one half of its circumference. The position-determining plate 50 is positioned normally on the top plate 46 of the engagement tool 3 when the engagement fitting 3 and the fixing fitting 5 are temporarily engaged to thereby determine the position of the engagement fitting 3 and the fixing fitting 5. That is, the plate 46 is disposed so that the edge 50' abuts the top surface of the plate 46 along the edge thereof adjacent the engagement portion, with the plates 46 and 50 being disposed generally perpendicular to one another as shown in Figures 11 and 12. The driving member 51 has formed therein a first insertion hole 52 into which the engagement portion 35 of the engagement member 31 is inserted, and a second insertion hole 53 into which the position-determining projection 49 of the engagement member 31 is inserted. These holes 52 and 53 extend axially through the diametrical half of member 51 which is sidewardly spaced from plate 50. Stepped grooves 55 are formed around the outer cylindrical wall of the driving member 51 and, in addition, an invertedly-bent spring 57 is mounted on the outer wall. As shown in Figures 9 and 10, the invertedly-bent spring 57 has a substantially J-shaped configuration, and it is partly disposed on opposite cylindrical side surfaces of the driving member 51. Spring 57 is firmly fixed in place by a pin 59 which extends diametrically across the driving member 51. The pin 59 passes through a hole in the spring, and also penetrates through the first insertion hole 52 and is used as an engagement pin with which the engagement portion 35 engages. The manner in which the above-described engagement fitting 3 and the fixing fitting 5 are used will be described. First, a mounting hole (not shown) is formed in a first board-shaped body, e.g. a piece of compressed plywood, and the engagement fitting 3 is placed in such a manner that the engagement member 31 extends in the direction aligned with the board surface. Thereafter, the engagement fitting 3 is driven into the mounting hole to be fitted therein. By this operation, the stepped grooves 47a bite into the mounting hole, thereby fixing the engagement fitting 3 in place. Further, when the fixing fitting 5 is driven into a mounting hole (not shown) formed in another piece of compressed plywood, the invertedly-bent spring 57 and the stepped grooves 55 bite into the mounting hole, thereby firmly fixing the fixing fitting in place. The invertedly-bent spring 57 is inserted into the mounting hole as it is being obliquely moved, but, when the fixing fitting 5 is subjected to a pulling-out force, the spring bites into the inner wall of the mounting hole, thereby blocking the pulling-out force. Subsequently, the two pieces of compressed plywood are placed normally (i.e. perpendicularly) to one another and, as shown in Figure 11, when the engagement portion 35 of the engagement member 31 is inserted into the first insertion hole 52 of the fixing fitting 5, the engagement pawl 35a of the engagement portion 35 abuts against then temporarily engages with the pin 59 by the urging force of the spring 37. With this condition, a tool such as a hexagonal wrench is inserted in the wrench hole 45 of the rotor portion 39, and the cam portion 41 is rotated through 90 degrees in the counterclockwise direction into the position shown in Figure 12. As a result, as shown in Figure 12, by the operation of the cam portion 41, the engagement member 31 is moved radially inwardly in the direction of arrow B through the maximum stroke to bring the engagement pawl 35a into engagement with the pin 59. This rotation of the cam portion 41 positions it in an area in which the cam portion 41 is kept from rotating in the opposite direction even if it is subjected to a load in the direction opposite to that of the arrow B. Further, when the cam portion 41 is rotated through 100 degrees, the ridges 41c and 41d of the cam portion 41 fit into the grooves 46d and 46e of the case 33 to fix the position of the cam portion 41, thereby locking the above-mentioned engagement. By the above-described operations, the two pieces of compressed plywood are firmly assembled. When it is necessary to demount the engagement fitting 3, the rotor portion 39 is first rotated in the clockwise direction as viewed in Figure 12. By this operation, the ridges 41c and 41d of the cam portion 41 become disengaged from the grooves 46d and 46e of the case 33, and the engagement pawl 35a is moved in the direction opposite to that of the arrow B to become disengaged from the pin 59. When the cam portion 41 has been rotated through 100 degrees, the projection 41a of the cam portion 41 abuts against the circumferential wall 36b of the annular portion 36 so as to cause the annular portion 36 to rotate in the clockwise direction. Thus, the engagement portion 35 is allowed to rotate in the clockwise direction against the urging force of the spring 37. As a result, the engagement pawl 35a becomes separated from the pin 59, thereby enabling the engagement portion 35 to be disengaged from the fixing fitting 5. When the cam portion 41 is rotated through 108 degrees, however, the ridge 41c and 41d of the cam portion 41 fit into the grooves 46c and 46d of the case 33, thereby fixing the position of the rotary member 32 as well. As described above, the board-shaped body assembling instrument 1 in accordance with the foregoing embodiment is provided with a mechanism which very easily enables the engagement fitting 3 and the fixing fitting 5 to be temporarily engaged and thereafter be engaged firmly. Therefore, board-shaped bodies can be easily and firmly assembled. Further, when the conventional assembling instrument which is adapted to be threaded into board-shaped bodies is used to assemble pieces of compressed plywood, it may encounter the problem that the screw becomes disengaged if a large load is applied to the assembling instrument. In contrast, the assembling instrument 1 in accordance with the foregoing embodiment has the fixing tool 5 provided with an invertedly-bent spring 57 which is firmly fixed in place by the pin 59 and which is capable of blocking a force acting to pull out the fixing fitting. This arrangement enables the assembling instrument to withstand a large load even when it is used to assemble pieces of compressed plywood and also enables a rigid assembly of the instrument. Since the engagement member 31 projects in the direction aligned with the surface of the board-shaped body, there is no risk of damaging other board-shaped bodies and the assembled board-shaped bodies can be stacked. As described in detail, the instrument for assembling board-shaped (i.e. plate-like) bodies in accordance with the present invention comprises the engagement fitting and the fixing fitting and is provided with a mechanism in which the engagement pawl of the engagement fitting engages with the engagement pin of the fixing fitting thereby enabling the board-shaped bodies to be firmly assembled. Further, since the engagement fitting is provided with the slip-off prevention stepped grooves, while the fixing fitting is provided with the member and stepped grooves for the prevention of slip-off, the instrument can withstand a large load even when it is used to assemble pieces of compression plywood or the like. In this way, the instrument enables firm assembly of pieces of compressed plywood.

Claims: An apparatus for fixedly securing first and second plate-like bodies together in generally perpendicular relationship to one another, said apparatus comprising: an engagement fitting (3) adapted to be fixedly secured to said first body, said engagement fitting including a casing (33) adapted to be positioned within an opening in said first body, said casing having means (47a) associated with an outer peripheral wall (47) thereof for gripping engagement with a wall defining said opening for fixedly securing said casing within said opening, said casing having a slot (48) extending radially therethrough, an engagement member (31) loosely confined within the interior of said casing for permitting radial movement of said engagement member relative to said casing, said engagement member (31) including an engagement portion (35) projecting radially outwardly from an outer peripheral surface thereof in a cantilever fashion, said engagement portion terminating in a hook-like pawl (35a) at the radially outer free end thereof, said engagement portion (35) projecting radially outwardly through the slot (48) in said casing, and a rotary member (32) having a portion (43) which is rotatably and non-radially movably supported within said casing (33) for rotation relative thereto about the axis of said casing (33), said rotary member (32) having a cam part (41) fixed thereto in eccentric relationship relative to said axis and rotatably disposed within the opening of said engagement member (31) for effecting radial displacement of said engagement member relative to said casing (33) in response to rotation of said rotary member (32), a fixing fitting (5) adapted to be fixedly secured within an opening of said second body, said fixing fitting comprising a one-piece member having an annular part which is positionable within said last-mentioned opening, said annular part having means (55) on an outer peripheral surface thereof for gripping engagement with the wall defining said last-mentioned opening, said fixing fitting (5) having an opening (52) projecting axially of said annular part for accommodating said engagement portion (35) therein, characterized in that, the casing (33) is a one-piece annular casing, the engagement member (31) is an annular engagement member inserted into the annular casing (33) and said fixing fitting (5) having an engagement pin (59) fixedly supported on said annular part and extending across said last-mentioned opening (52) for engagement with the pawl (35a) on said engagement portion (35), and stop means (41a; 36c) coacting between said engagement member (31) and said rotary member (32) for limiting relative rotation therebetween to facilitate disengaging said pawl (35a) from said engagement pin (59) of said fixing fitting. An apparatus according to Claim 1, wherein said annular casing (33) has a plate-like portion (46) which is fixed thereto at one axial end thereof, and wherein said rotary member (32) has said annular portion (43) rotatably supported on said casing adjacent the other axial end thereof. An apparatus according to Claim 2, wherein said fixing tool (5) includes a plate-like part (50) which is fixed to said annular part adjacent one axial end thereof, said plate-like part (50) extending over about one diametrical half of said annular part and having an edge which is adapted to abuttingly contact a surface of the plate-like portion (46) associated with said casing (33). An apparatus according to Claim 2, wherein said casing (33) has a projection (49) which is fixed thereto and projects outwardly from the outer periphery thereof in generally parallel relationship with said engagement portion (35), and said fixing tool (5) having a recess (53) which opens axially of said annular part for snugly accommodating said projection (49) therein. An apparatus according to Claim 2, including torsion spring means (37) coacting between said casing (33) and said engagement member (31) for rotatably urging said engagement portion (35) toward a position of engagement with said engagement element (59). An apparatus according to Claim 2, including rotary stop means (41b;46b) cooperating between said casing (33) and said rotary member (32) for limiting the rotational displacement of said rotary member, and detent means (41c,d,e;46c,d,e) coacting between said casing (33) and said rotary member (32) for defining discrete positions for said rotary member (32). An apparatus according to Claim 2, including stop means (36a) between said casing (33) and said engagement member (31) for limiting relative rotation therebetween.

Inventors: MATSUI, KAZUHIRO
Applicants: KABUSHIKI KAISHA KOJIMA SHOHTEN, MATSUI, KAZUHIRO
Application year: 1989
Main classification: F16B12
IPC codes: A47B47, F16B12, F16B5