Frame corner connection structure

Abstract

To provide a corner part connecting structure of a frame having a position adjusting function capable of accurately butting end faces of adjacent frame materials to each other, preventing a member constituting the position adjusting function from being exposed to the appearance of the frame, dispensing with machining such as cutting and boring on the frame material itself, and having excellent practicality.SOLUTION: In the picture frame 1 formed by cutting an end face of a frame material 2 at an inclination angle A and butting it to form a corner part of an internal angle 2A, a groove part 3 with a lip is formed on the frame inside of the frame material 2, a connecting tool 4 has a pair of left and right connecting leg pieces 41 capable of being inserted into the groove part 3 from the end face of the frame material 2, an adjustment clearance D in the frame inside-outside direction is provided between the connecting leg piece 41 and the inside face of the groove part 3, and a female screw hole 4 5 penetrating the connecting leg piece 41 in the frame inside-outside direction at a crossing angle equal to or less than the inclination angle A is formed in the connecting leg piece 41. When a male screw member 5 is screwed into the female screw hole 45 from the inside of the frame and advanced, the frame material 2 can be moved to the corner part side.SELECTED DRAWING: Figure 7

Description

[Technical Field]

[0001] The invention disclosed in this application relates to a corner connection structure for a frame constructed by framing frame materials, primarily made of extruded profiles, into a rectangular or other polygonal shape when viewed from the front, in which the end faces of the frame materials are cut diagonally and butt-joined. [Background technology]

[0002] A widely used picture frame is one in which frame members with uniform cross sections, made of extruded shapes such as aluminum alloy or hard synthetic resin, are framed into a rectangular shape when viewed from the front, the end faces of the frame members are cut at a 45-degree angle relative to the length of the frame members, and the end faces of the frame members are butt-jointed in a so-called "miter joint" configuration. This type of frame requires a connecting means for tightly fitting the end faces of the frame members together at the corners without misalignment or gaps. Various connecting means have been proposed, including a corner connector with a pair of legs that are connected to each other in a generally L-shape when viewed from the front. One leg and the other leg are inserted or engaged with the ends of the two frame members to be butt-joined, respectively, and the legs and frame members are fastened together using fastening means such as screws, levers, cams, or check pawls so that a force is applied in the direction of the butt faces. Patent Documents 1 to 7 disclose corner connection structures for picture frames that utilize the above-mentioned connecting means. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Utility Model Application Publication No. 55-49631 [Patent Document 2] Japanese Utility Model Application Publication No. 59-18967 [Patent Document 3] Publication number 2-27826 [Patent Document 4] Japanese Utility Model Application Publication No. 4-58176 [Patent Document 5] Japanese Patent Application Laid-Open No. 2003-290006 [Patent Document 6] Japanese Patent Application Laid-Open No. 2003-339497 [Patent Document 7] Japanese Patent Application Laid-Open No. 2007-117406 Summary of the Invention [Problem to be solved by the invention]

[0004] The applicant, (1) It has an easy-to-use, highly accurate position adjustment function that can easily eliminate misalignment, gaps, and steps at the butt surfaces of two frame materials. (2) In order to improve the design of the exterior, the corner connectors and fixing screws that make up the position adjustment function must not be exposed on the front or outer periphery of the frame, and must not protrude conspicuously on the back side. (3) In order to maximize the benefits of using extruded shapes and reduce production costs, the frame material itself must be subjected to as little tedious processing as possible, such as cutting and drilling. The above three conditions were set and prior art, including the conventional corner portion connection structure, was investigated from various angles, but no practical prior art that satisfied the above three conditions was found.

[0005] Therefore, the invention disclosed in this application proposes a new corner connection structure for a picture frame that satisfies the above three conditions. [Means for solving the problem]

[0006] In order to achieve the above-mentioned object, the invention disclosed in this application is a corner connection structure for a frame formed by framing a plurality of frame members made of extruded shapes with a uniform cross section, in which the end faces of the frame members are cut so as to form an inclination angle A with respect to the length direction of the frame members, and a connector is interposed between two adjacent frame members, and the end faces of both frame members are butt-joined to form a corner with an interior angle 2A, and the frame members are provided with a groove with a lip that opens to the inside of the frame and extends in the length direction of the members, and the connector has a pair of left and right connecting leg pieces that can be inserted into the groove from the end faces of the frame members. An adjustment clearance in the inside and outside of the frame is provided between the connecting leg piece and the inner surface of the groove, and a female threaded hole is formed in the connecting leg piece, penetrating the connecting leg piece in the inside and outside of the frame at an intersection angle with respect to the longitudinal direction of the connecting leg piece that is the same as or less than the inclination angle A.The connecting leg pieces of the connector are inserted into the grooves of both adjacent frame materials on either side of the corner portion, and a male screw member is screwed into the female threaded hole from the inside of the frame and advanced, so that the tip of the male screw member abuts against the rear wall surface of the groove, moving the frame material toward the corner portion.

[0007] Furthermore, the invention disclosed in this application is characterized in that, in the corner portion connection structure of the above-mentioned picture frame, a recessed groove into which the tip of the male screw member is inserted is formed on the rear wall surface of the groove portion, extending in the material length direction of the frame material.

[0008] Furthermore, the invention disclosed in this application is characterized in that, in the corner portion connection structure of the above-mentioned picture frame, the connecting leg piece is formed so that the clearance provided between it and either the front or rear lip portion of a pair of lip portions surrounding the groove portion is different from the clearance provided between it and the other lip portion. [Effects of the Invention]

[0009] According to the frame corner connection structure configured as described above, by advancing the male screw member threaded into the female screw hole of the connector from the inside of the frame toward the outside of the frame, the frame material can be moved a small distance toward the corner, allowing the end faces of adjacent frame materials to butt together neatly. Since no cutting, drilling, or other processing is required near the corners of the frame material, frames of various sizes with different vertical and horizontal dimensions can be efficiently manufactured at low production costs. Furthermore, since connectors, screws, etc. are not exposed on the front, outer periphery, or back of the corners, the appearance is also improved. [Brief explanation of the drawings]

[0010] [Figure 1] 1 is a schematic perspective view showing an example of a frame to which the invention disclosed in the present application is applied. [Figure 2] BB cross-sectional view showing the cross-sectional shape of the frame material that constitutes the four sides of the frame. [Figure 3] 10 is a partially enlarged perspective view of a corner portion of the frame as viewed from the direction C inside the frame. FIG. [Figure 4] FIG. 4 is a perspective view of a connector used to connect the corner portions. [Figure 5] 10 is an explanatory diagram illustrating the operation of a position adjustment function of the connector. FIG. [Figure 6] 10A is a partial front view and FIG. 10B is a cross-sectional view showing a connected state before the position of the corner portion is adjusted. [Figure 7] 10A is a partial front view showing the connected state after the position of the corner portion is adjusted, and FIG. 10B is a cross-sectional view showing the connected state after the position of the corner portion is adjusted. DETAILED DESCRIPTION OF THE INVENTION

[0011] Hereinafter, embodiments of the invention disclosed in the present application will be described with reference to the drawings. Figure 1 shows an example of a frame to which the invention disclosed in the present application is applied. The illustrated frame 1 has a rectangular shape from the front that is close to a square, and a transparent glass panel 10 is fitted into the front side of the frame. However, in this invention, there are no particular limitations on the aspect ratio of the frame 1 or the presence or absence of the glass panel 10.

[0012] The frame material 2 surrounding the four sides of the frame 1 is made of shaped materials with the same cross-sectional shape, formed by extrusion molding of, for example, aluminum alloy or other metals, or hard resin. An example of the cross-sectional shape of the frame material 2 is shown in Figure 2. Note that, when explaining the relative positions and directions of operation of parts and components below, the direction perpendicular to the surface when the frame 1 is viewed from the front (front) will be referred to as the front-to-back direction or depth direction, and the center side of the plane enclosed by the frame material 2 will be referred to as the frame inner side, and the outside will be referred to as the frame outer side. Furthermore, in explanations referring to drawings (e.g., Figures 1, 2, 3) that show the frame 1 placed on a horizontal surface with its front side facing up, the aforementioned direction perpendicular to the surface will also be referred to as the up-down direction.

[0013] The frame material 2 of the exemplary embodiment has a peripheral wall portion 21 that has a uniform width in the front-to-back direction of the frame 1 and forms the peripheral surface of the frame 1, a front outer frame portion 22 that extends outside the frame from the front edge of the peripheral wall portion 21, a front inner frame portion 23 that extends inside the frame while sloping toward the back from the inner edge of the front outer frame portion 22, a back wall portion 24 that extends inside the frame from the rear edge of the peripheral wall portion 21, and a glass surface material receiving portion 25 that extends inside the frame from a position near the front edge of the peripheral wall portion 21.

[0014] The outer surface of the peripheral wall 21 is flat, and two lip-equipped grooves 3 are formed on the inner surface at a predetermined interval in the front-to-rear direction. The grooves 3 open toward the inside of the frame and extend in the longitudinal direction. Each groove 3 is formed by a pair of front and rear groove walls 31 that protrude from the peripheral wall 21 toward the inside of the frame, and a pair of opposing lip portions 32 that protrude in the front-to-rear direction from the inner frame edges of each groove wall 31. In the frame member 2 of the illustrated embodiment, the rear groove wall 31 of the rear groove 3 is integrated with the back wall 24, and the rear lip portion 32 protrudes forward from a midpoint of the back wall 24. The inner dimensions of the front groove 3 and the rear groove 3 are the same. The peripheral wall 21 in the portion surrounded by these grooves 3 is thickened toward the inside of the frame. A shallow recessed groove 33 extending in the longitudinal direction of the frame member 2 is formed on the rear wall surface of the thickened portion when viewed from the groove 3 side.

[0015] In addition, an outer frame rib 26 extends from the back side of the outer edge of the front outer frame portion 22, and a lip portion 27 protruding from the rear edge of the outer frame rib 26 toward the inside of the frame and a lip portion 28 protruding from the outer surface of the peripheral wall portion 21 toward the outside of the frame face each other, and a frame outer groove portion 29 with a lip that opens to the rear is also formed on the back side of the front outer frame portion 22.

[0016] Figure 3 is a partially enlarged perspective view of a corner of this frame 1, viewed from the inside of the frame in direction C. The end faces of two adjacent frame materials 2 sandwiching the corner are cut so that they form an inclination angle A with respect to the longitudinal direction of the frame materials 2 when viewed from the front, and the end faces of these frame materials 2 are butt-joined to form a corner with an interior angle 2A. In the rectangular frame 1 viewed from the front, the inclination angle A is 45 degrees, and the interior angle 2A of the corner is 90 degrees.

[0017] 4 is a perspective view of the components used in the connecting structure of this corner portion. This corner portion uses a connector 4 that is generally L-shaped in front view and inserted into groove 3 of frame material 2, multiple male screw members 5 that screw into connector 4, a corner plate 6 that is L-shaped in front view and inserted into outer-frame groove 29 of frame material 2, and a fixing screw 61 for fastening corner plate 6 to frame material 2.

[0018] The connector 4, which is the main part of the present invention, is made of, for example, hard resin, aluminum alloy, or other metal. The connector 4 has a pair of left and right connecting legs 41 that are connected in a roughly L-shape when viewed from the front. These connecting legs 41 are inserted into the groove 3 from the end face of the obliquely cut frame material 2, as shown in Figure 3.

[0019] Each connecting leg piece 41 is formed so that its central portion 42 in the front-to-rear direction is thicker toward the inside of the frame than its front edge portion 43 and rear edge portion 44, forming a generally convex cross section. At the inside corner where the left and right connecting leg pieces 41 intersect, the front edge portions 43 and rear edge portions 44 on both sides are connected at right angles, and the central portion 42 is formed so as to be continuous via a curved concave surface that is a quarter-circular arc when viewed from the front. A triangular mark 46 is formed on the curved concave surface. This mark 46 is used to distinguish the front-to-rear direction, as will be described later.

[0020] A protrusion 47 having a substantially triangular cross section is formed on at least one edge surface in the front-to-rear direction of each connecting leg piece 41. This protrusion 47 comes into sliding contact with the inner surface of the groove wall portion 31, preventing rattling of the connecting leg piece 41 in the front-to-rear direction and reducing contact friction between the connecting leg piece 41 and the frame material 2. In addition, to make it easier to insert the connecting leg piece 41 into the groove portion 3, each protrusion 47 is formed with a tapered surface 48 that decreases in height toward the tip of the connecting leg piece 41.

[0021] In the illustrated embodiment, two female threaded holes 45 are formed on each of the left and right sides of the central portion 42 of each connecting leg piece 41, penetrating the connecting leg piece 41 in the inward and outward directions of the frame. These female threaded holes 45 are formed obliquely so that their hole axes form an intersecting angle with the longitudinal direction of the connecting leg piece 41 that is the same as or slightly smaller than the inclination angle A when viewed from the front (see Figures 6 and 7). Male threaded members 5 are screwed into each female threaded hole 45 from the inside of the frame. In the illustrated embodiment, set screws (hexagon socket set screws) are used as the male threaded members 5. However, male threaded members 5 with heads can also be used.

[0022] 6 and 7 show a connected state in which the left and right connecting leg pieces 41 of the connector 4 are inserted into the grooves 3 of two adjacent frame members 2 sandwiching a corner, with the end faces of the two frame members 2 butted together at the corner. When the connecting leg pieces 41 are inserted into the grooves 3 of the frame members 2, the front and rear edges 43 and 44 are sandwiched between the rear wall surface of the grooves 3 and the lip portions 32, and the central portion 42 is held so that it is exposed to the inside of the frame between the front and rear lips 32. The thicknesses of the front and rear edges 43 and 44 are formed slightly smaller than the inner dimensions of the rear wall surface of the grooves 3 and the lip portions 32. Therefore, the connecting leg pieces 41 inserted into the grooves 3 are held within the grooves 3, leaving a gap that allows some movement in and out of the frame. This gap serves as an adjustment clearance D for moving the frame member 2 toward the corner.

[0023] When the male screw member 5 is screwed into the female screw hole 45 formed in the connecting leg piece 41 from inside the frame, the tip of the male screw member 5 abuts against the back wall surface of the groove portion 3. When the male screw member 5 is further advanced, the frame material 2 is pushed outward from the frame by the clearance D described above.

[0024] Here, the principle of operation of the position adjustment function in this corner connection structure will be explained with reference to Figure 5. Figures 5(a) to 5(c) are explanatory diagrams showing a simplified front view of the frame members 2 connected across the corner and the connector 4 interposed between them. In each figure, the horizontally arranged frame member 2x is pushed outward in advance by the male screw member 5 threaded into the horizontally facing connecting leg piece 41x, and is brought close to a position where its end face coincides with the abutting surface of the corner portion.

[0025] On the other hand, as shown in Figure 1(a), the vertically oriented frame member 2y is first inserted into the connecting leg piece 41y so that the frame member 2y is closer to the inside of the frame than the connecting leg piece 41y. At this time, the gap D between the connecting leg piece 41y and the groove 3 is provided on the inside of the frame of the connecting leg piece 41y. Then, as shown in Figure 1(b), the frame member 2y is pushed toward the corner. In this state, the end face of the vertically oriented frame member 2y is shifted toward the inside of the frame relative to the end face of the horizontally oriented frame member 2x. From this state, when the male screw member 5 is turned and advanced, the tip of the male screw member 5 pushes the frame member 2y obliquely toward the corner, as shown in Figure 1(c). Then, the gap D between the connecting leg piece 41y and the groove 3 moves to the outside of the frame of the connecting leg piece 41y. In this way, the end face of the vertically oriented frame member 2y and the end face of the horizontally oriented frame member 2x can be precisely aligned.

[0026] Furthermore, if the intersection angle of the female thread hole 45 with the connecting leg piece 41 is made slightly smaller than the inclination angle A of the end face of the frame material 2, the effect of moving the end face of the frame material 2 toward the butt surface of the corner portion can be further enhanced.

[0027] In the corner connection structure shown in Figures 6 and 7, two female threaded holes 45 are formed in each of the connecting leg pieces 41 that are inserted into the grooves 3 of each frame material 2. Therefore, by changing the way the two male threaded members 5 are fastened, it is possible to slightly misalign the axis of the frame material 2 and the axis of the connecting leg pieces 41. In addition, a recessed groove 33 is formed in the inner wall surface of the groove 3 against which the male threaded member 5 abuts, and the threads of the male threaded member 5 bite into this recessed groove 33, firmly holding the positioned frame material 2 without shifting. To make it easier for the male threaded member 5 to bite into, it is preferable to set the width of the recessed groove 33 to be slightly smaller than the nominal diameter of the male threaded member 5, approximately the root diameter of the male threaded member 5.

[0028] In the illustrated embodiment, more detailed considerations have been made with respect to the adjustment clearance D formed between the groove 3 of the frame material 2 and the connecting leg piece 41. That is, the front edge 43 and rear edge 44 of the connecting leg piece 41 are flush with each other on the rear side, but the thickness toward the inside of the frame is slightly different, with the rear edge 44 being thinner than the front edge 43. That is, as shown in FIG. 6, the clearance in the frame-exterior direction of the connecting leg piece 41 inserted into the groove 3 is maintained at D on the front edge side and D+α on the rear edge side. In actual dimensions, when the inner dimension of the groove 3 in the front-rear direction is approximately 15 to 20 mm and the inner dimension in the frame-exterior direction is approximately 4 to 5 mm, the clearance on the front edge side is set to approximately D=0.2 mm and the clearance on the rear edge side is set to approximately D+α=0.3 mm (α=0.1 mm).

[0029] In this way, by making the clearance between the connecting leg piece 41 and the groove portion 3 different on the leading edge side and the trailing edge side, when the male screw member 5 is advanced to push the frame material 2 outward from the frame, the peripheral wall portion 21 of the frame material 2 will be inclined inward and outward from the frame, as shown in Figure 7(c). If the clearance on the leading edge side is made smaller than the clearance on the trailing edge side, the front portion of the frame material 2 (front outer frame portion 22 and front inner frame portion 23) in particular can be firmly pressed against the abutting surfaces of the corner portions, resulting in an attractive finish in which the end faces of the frame materials 2 are in close contact with each other.

[0030] Furthermore, in the illustrated embodiment, as shown in FIG. 2, the connectors are inserted in reverse order into two front and rear grooves 3 provided in the frame material 2. The connectors 4 are inserted into the front groove 3 so that the clearance at the leading edge is smaller than the clearance at the trailing edge, and into the rear groove 3 so that the clearance at the leading edge is larger than the clearance at the trailing edge. This allows the front portion (front outer frame portion 22 and front inner frame portion 23) and the rear portion (back wall portion 24) to be neatly fitted together at their respective butt joints, even for frame material 2 with a large front-to-rear dimension, as illustrated, while subtly curving the middle portion. The triangular mark 46 formed on the curved concave surface of the connector 4 facilitates the use of the connector 4 in the front and rear directions.

[0031] The corner plate 6 is inserted into the outer frame grooves 29 of the two adjacent frame materials 2, sandwiching the corner portion. After adjusting the positions of both frame materials 2 so that the end faces of both frame materials 2 precisely align at the corner portion, the two are fastened by tightening a fixing screw 61 from the rear side. There are no particular restrictions on the shape of the head of this fixing screw 61, and a set screw can also be used.

[0032] As explained above, with this frame corner connection structure, the frame material 2 can be moved a small distance toward the corner by advancing the male screw member 5 threaded into the female screw hole 45 of the connector 4 from the inside of the frame toward the outside of the frame, allowing the end faces of adjacent frame materials 2 to neatly butt against each other. The frame material 2 itself does not require any machining, drilling, or other processing other than cutting the end faces. Therefore, frames of various sizes with different vertical and horizontal dimensions can be efficiently manufactured at low production costs. Furthermore, because connectors, screws, etc. are not exposed on the front, outer periphery, or back near the corners, the exterior design is also improved.

[0033] This corner connection structure can also be applied to frames other than typical rectangular frames. For example, in a frame in which six frame members are assembled to form a regular hexagonal front shape, the inclination angle A is 60 degrees and the corner interior angle 2A is 120 degrees. Therefore, the intersection angle between the female screw holes 45 formed in the connecting leg pieces 41 of the connector 4 and the connecting leg pieces 41 is also set to 60 degrees or less. In a frame in which eight frame members are assembled to form an octagon, the inclination angle A is 67.5 degrees and the corner interior angle 2A is 135 degrees. Therefore, the intersection angle between the female screw holes 45 formed in the connecting leg pieces 41 of the connector 4 and the connecting leg pieces 41 is also set to 67.5 degrees or less. In a frame in which three frame members are assembled to form an equilateral triangle, the inclination angle A is 30 degrees and the corner interior angle 2A is 60 degrees. Therefore, the crossing angle between the female screw hole 45 formed in the connecting leg 41 of the connector 4 and the connecting leg 41 is set to 30 degrees or less. Furthermore, even for frames whose front shape is not a regular polygon but a scalene polygon, or frames with corners with different crossing angles, no special processing of the frame material is required, so frame materials can be easily connected by simply preparing multiple types of connectors corresponding to the crossing angles. This significantly improves the finished quality of the frame and manufacturing efficiency.

[0034] The technical scope of the invention disclosed in this application should not be construed as being limited by the exemplified embodiments, but should be construed conceptually based on the claims. The names of elements used in the claims and specification are for convenience in making the invention easier to understand specifically, and the names do not unnecessarily limit the concepts or properties of the elements. When implementing the invention disclosed in this application, the detailed shape, dimensions, structure, material, quantity, combination form with other elements, relative positional relationship, etc. of elements not specifically specified in the claims may be appropriately modified within the scope of obtaining effects substantially equivalent to or greater than those of the exemplified embodiments. [Explanation of symbols]

[0035] 1. Picture Frame 10 Glass surface material 2 Frame material 21 Peripheral wall section 22 Front outer frame 23 Front inner frame 24 Back wall part 25 Glass surface material receiving part 26 Outer frame rib 27 Lip 28 Lip 29 Frame outer groove 3 Groove 31 Groove wall 32 Lip 33 Groove 4 Connectors 41 Connecting leg piece 42 Central part 43 leading edge 44 Trailing edge 45 female threaded hole 46 Landmark 47 protrusion 48 Tapered surface 5 Male threaded member 6 Corner Plates 61 Fixing screw

Claims

1. In a picture frame formed by framing a plurality of frame members made of extruded shapes with a uniform cross section, The end surface of the frame material is cut so as to have an inclination angle A with respect to the longitudinal direction of the frame material, A corner connection structure for a picture frame in which a connector is interposed between two adjacent frame materials and the end faces of the frame materials are butt-joined to form a corner portion of an interior angle 2A, The frame material is provided with a groove with a lip that opens to the inside of the frame and extends in the material length direction, The connector has a pair of left and right connecting leg pieces that can be inserted into the groove from the end face of the frame material, An adjustment clearance is provided between the connecting leg piece and the inner surface of the groove portion in the frame inward and outward directions, The connecting leg piece has a female screw hole formed therein, which penetrates the connecting leg piece inward and outward directions of the frame at an intersection angle equal to or less than the inclination angle A with respect to the longitudinal direction of the connecting leg piece, The connecting leg pieces of the connecting tool are inserted into the grooves of both adjacent frame members sandwiching the corner portion, and a male screw member is threaded into the female screw hole from the inside of the frame and advanced, so that the tip of the male screw member abuts against the inner wall surface of the groove, moving the frame member toward the corner portion. A corner connection structure for a picture frame.

2. The corner connection structure of a picture frame according to claim 1, A recessed groove into which the tip of the male screw member is inserted is formed on the inner wall surface of the groove portion, extending in the length direction of the frame material. A corner connection structure for a picture frame.

3. The corner connection structure of a picture frame according to claim 1 or 2, The connecting leg piece is formed so that a clearance provided between the connecting leg piece and one of the front and rear lip portions of a pair of lip portions surrounding the groove portion is different from a clearance provided between the connecting leg piece and the other lip portion. A corner connection structure for a picture frame.

Images