JP7849020B2 - Clamping device - Google Patents

Description

This invention relates to a clamping device for connecting multiple pipes in a direction perpendicular to each other.

Multiple pipes are connected in T-shapes or L-shapes using clamps like those described in Patent Document 1 to assemble platforms, scaffolding, and other structures. However, these common clamps have protruding parts such as bolts, which pose a risk of snagging on clothing, and they also have an unattractive appearance.

Furthermore, a pipe fitting called a key clamp (registered trademark: KEEKLAMP), as shown in Non-Patent Document 1, is also known. This key clamp is made of cast iron and lacks protrusions such as bolts, making it safer and more aesthetically pleasing compared to general clamps like the one shown in Patent Document 1.

Patent No. 6930716

Fuji Alpha Co., Ltd., Product Description "Key Clamp/Key Light", [online], [Searched August 30, 2022], Internet <URL: http://www.f-alpha.co.jp/keeklamp.html>

As already explained, conventional clamps like the one in Patent Document 1 have problems with safety due to protrusions and aesthetic issues, which limits their use to specific purposes and locations.

Furthermore, the key clamp shown in Non-Patent Document 1 was made of cast iron, which resulted in high manufacturing costs and a tendency to break easily upon impact. Additionally, it required the production of a separate casting for each connection configuration, limiting design flexibility.
Therefore, the objective of the present invention is to provide a clamping device that is aesthetically pleasing, inexpensive, and easy to use.

To solve the above-mentioned problems, the present invention provides a clamping device for connecting multiple pipes in mutually orthogonal directions, comprising a first clamp attachable to the outer circumference of a first pipe and a second clamp attachable to the outer circumference of a second pipe. The first clamp comprises a first cylindrical portion capable of holding the first pipe and a plurality of engaging protrusions formed on the outer surface of the first cylindrical portion. The second clamp comprises a second cylindrical portion capable of holding the second pipe and a pair of engaging legs protruding from the second cylindrical portion. The device is configured such that the first pipe and the second pipe can be connected in mutually orthogonal directions by engaging the pair of engaging legs with the engaging protrusions on both sides.

As described above, the present invention allows pipes to be connected in mutually perpendicular directions by engaging the first clamp and the second clamp perpendicularly. This configuration allows for the creation of a clamping device with a cleaner appearance than conventional clamps.

Furthermore, since it does not need to be integrally cast like a key clamp, it is possible to use rust-resistant, inexpensive, and crack-resistant materials (such as aluminum). Therefore, an inexpensive and easy-to-use clamping device can be provided.
Furthermore, increasing the variety of clamps allows for greater flexibility in connection methods depending on how they are combined, making them usable in a wider range of situations.

This is a perspective view of the first clamp. (a) Plan view, (b) Front view, and (c) Side view of the first clamp. This is a perspective view of the second clamp. The second clamp is shown in (a) a plan view, (b) a front view, (c) a bottom view, and (d) a side view. This is a perspective view of the third clamp. The third clamp is shown in (a) a plan view, (b) a front view, (c) a bottom view, and (d) a side view. This is a perspective view showing two pipes connected in a T-shape using a clamping device according to the embodiment. These are enlarged sections of Figure 7, where (a) is a view from direction A1, (b) is a view from direction A2, and (c) is a view from direction A3. This is a perspective view of Figure 7, with the pipes connected at a right angle. These are enlarged sections of Figure 9, where (a) is a view from direction B1 and (b) is a view from direction B2. This is a perspective view of the second clamp, which has a different length. (a) Plan view, (b) Front view, (c) Bottom view, and (d) Side view of the second clamp with different lengths. This is a perspective view of the sealing material. These are (a) a plan view, (b) a front view, and (c) a side view of the sealing material. This is a perspective view showing two pipes connected in an L-shape using a clamping device according to the embodiment. These are enlarged sections of Figure 15, where (a) is a view from direction C1, (b) is a view from direction C2, and (c) is a view from direction C3. This is a perspective view of Figure 15, with pipes connected at a right angle. These are enlarged sections of Figure 17, where (a) is a view from direction D1, (b) is a view from direction D2, and (c) is a view from direction D3. This is a perspective view of a trolley configured using the clamping device according to the embodiment.

Embodiments of the present invention will be described with reference to the figures. Note that the X, Y, and Z directions indicated in each drawing represent mutually orthogonal directions. These X, Y, and Z directions are shown for the convenience of explaining each drawing and do not represent common directions across drawings. For example, the X, Y, and Z directions in Figure 1 do not necessarily coincide with those in Figure 3.

Furthermore, the following explanation uses the terms "first pipe 55," "second pipe 56," and "third pipe 57." These names are used to distinguish pipes at connection points and do not represent the individual characteristics of the pipes themselves. In other words, they simply mean that the pipe held by the first clamp 10 is the first pipe 55, the pipe held by the second clamp 20 is the second pipe 56, and the pipe held by the third clamp 30 is the third pipe 57. Therefore, it is possible that a certain pipe might be "first pipe 55 (held by the first clamp 10)" at one connection point, but "second pipe 56 (held by the second clamp 20)" at another connection point.

The clamping device according to this embodiment is for connecting multiple pipes in mutually orthogonal directions and is composed of a combination of multiple clamps that are separable from each other. Specifically, when connecting two pipes, a first clamp 10 that can be attached to the outer circumference of the first pipe 55 and a second clamp 20 that can be attached to the outer circumference of the second pipe 56 are used. Furthermore, when connecting three pipes, in addition to the first clamp 10 and the second clamp 20, a third clamp 30 that can be attached to the outer circumference of the third pipe 57 is also used. Thus, the clamping device according to this embodiment can be configured by freely combining parts suitable for the number and direction of pipes to be connected. The individual parts will be described below.

First, as shown in Figures 1 and 2, the first clamp 10 comprises a first cylindrical portion 11 capable of holding the first pipe 55, and a plurality of engaging protrusions 13 formed on the outer circumferential surface 11a of the first cylindrical portion 11. The first clamp 10 according to this embodiment is made of metal, and is integrally formed (as a single part) from a material such as aluminum or an aluminum alloy. Furthermore, the first clamp 10 according to this embodiment is manufactured by processing an extruded profile.

The first cylindrical portion 11 is a cylindrical part through which a pipe can be inserted, and is formed with an inner diameter approximately equal to the outer diameter of the pipe (slightly larger than the outer diameter of the pipe, allowing for pipe insertion). Four engaging protrusions 13 protrude from the outer circumferential surface 11a of this first cylindrical portion 11 at equal intervals when viewed in the circumferential direction. These engaging protrusions 13 are angular in shape, as shown in Figures 1 and 2, and are formed to protrude radially. More specifically, the engaging protrusions 13 consist of two rising surfaces 13a and a zenith surface 13b connecting the ends of the rising surfaces 13a. The two rising surfaces 13a are parallel to each other and are formed perpendicular to the axial direction of the first cylindrical portion 11 (the X direction shown in Figure 1) (parallel to the Y direction or Z direction shown in Figure 1). The zenith surface 13b is formed perpendicular to the two rising surfaces 13a.

The engagement projection 13 is formed on the outer circumferential surface 11a of the first cylindrical portion 11, making the area where the engagement projection 13 is formed thicker in the radial direction than other areas. A first tapped hole 14 is formed through this thickened portion. The first tapped hole 14 is a through-hole with internal threads on its inner circumference, and is formed to engage with a bolt 50 (male thread) for fixing the pipe. After inserting the pipe into the first cylindrical portion 11, the bolt 50 inserted into the first tapped hole 14 is tightened inward, allowing the tip of the bolt 50 to press down on the pipe inserted into the first cylindrical portion 11. Forming this first tapped hole 14 in the thickened portion ensures the length of the internal threads (the fastening length of the bolt 50), thereby increasing the fastening force.

Furthermore, an engagement groove 12 is formed on the inner circumferential surface 11b of the first cylindrical portion 11. This engagement groove 12 is for receiving the tenon portion 41 of the sealing material 40 (described later), and is formed along the entire length of the first cylindrical portion 11 in the axial direction. In this embodiment, four engagement grooves 12 are formed at equal intervals when viewed circumferentially, and are arranged so as not to overlap with the engagement projections 13 when the first cylindrical portion 11 is viewed radially. This engagement groove 12 is formed in a dovetail shape as shown in Figures 1 and 2.

As shown in Figures 3 and 4, the second clamp 20 comprises a second cylindrical portion 21 capable of holding the second pipe 56, and a pair of engaging legs 27 protruding from the second cylindrical portion 21. The second clamp 20 according to this embodiment is made of metal, for example, aluminum or an aluminum alloy, and is integrally formed (as a single part). Furthermore, the second clamp 20 according to this embodiment is manufactured by processing an extruded profile.

The second cylindrical portion 21 is a roughly C-shaped section through which a pipe can be inserted. Its inner diameter is approximately equal to the outer diameter of the pipe (slightly larger than the outer diameter of the pipe, allowing insertion), in other words, it has the same inner diameter as the first cylindrical portion 11. Three ribs 24 are formed on the outer circumferential surface 21a of this second cylindrical portion 21. These ribs 24 are rectangular in shape, as shown in Figures 3 and 4, and are formed to protrude radially perpendicular to the axial direction of the second cylindrical portion 21 (the X direction shown in Figure 3). The three ribs 24 are arranged at 90-degree intervals in the circumferential direction, with one rib 24 protruding in the Y direction (as shown in Figure 3) and two ribs 24 protruding in the Z direction (as shown in Figure 3).

As described above, the rib 24 is formed on the outer circumferential surface 21a of the second cylindrical portion 21, making the area where the rib 24 is formed thicker in the radial direction than other areas. A second tapped hole 25 is formed through this thickened portion. The second tapped hole 25 is a through-hole with internal threads on its inner circumference, and is formed to engage with a bolt 50 (male thread) for fixing the pipe. After inserting the pipe into the second cylindrical portion 21, the bolt 50 inserted into the second tapped hole 25 is tightened inward, allowing the tip of the bolt 50 to press down on the pipe inserted into the second cylindrical portion 21. By forming this second tapped hole 25 in the thickened portion, the length of the internal thread (the fastening length of the bolt 50) can be ensured, thereby increasing the fastening force.

Furthermore, an engagement groove 22 is formed on the inner circumferential surface 21b of the second cylindrical portion 21. This engagement groove 22 is for receiving the tenon portion 41 of the sealing material 40 (described later), and is formed along the entire length of the second cylindrical portion 21 in the axial direction. This engagement groove 22 is formed with the same shape and spacing as the engagement groove 12 of the first clamp 10. However, since the second cylindrical portion 21 is not cylindrical but has a roughly C-shaped cross-section, there are only two fully formed engagement grooves 22. These engagement grooves 22 are positioned so as not to overlap with the rib 24 when the second cylindrical portion 21 is viewed radially.

The engaging leg portion 27 is a plate-shaped portion that protrudes in a direction perpendicular to the axial direction (X direction shown in Figure 3) of the second cylindrical portion 21 (Y direction shown in Figure 3). This engaging leg portion 27 protrudes in the direction of the opening (Y direction shown in Figure 3) from the substantially C-shaped opening in the cross-section of the second cylindrical portion 21. This engaging leg portion 27 protrudes from both ends of the opening, forming a pair of legs that are symmetrical to each other in cross-sectional view. The engaging leg portion 27 in this embodiment is a substantially U-shaped portion in cross-section, consisting of an expanding portion 27a, a protruding portion 27b, and a claw portion 27c. As shown in Figure 7, this engaging leg portion 27 can engage with the engaging projection 13 of the first clamp 10.
The expanded portion 27a is a part that extends in a direction away from each other (the Z direction shown in Figure 3) from both ends of the roughly C-shaped cross-section of the second cylindrical portion 21.

The protruding portion 27b is a part that extends perpendicularly from the end of the expanding portion 27a. This protruding portion 27b occupies almost the entire length of the engaging leg portion 27 (more than 80% of its total length), and the direction of protrusion of this protruding portion 27b (the Y direction shown in Figure 3) is substantially the same as the direction of protrusion of the engaging leg portion 27. The outer surface of this protruding portion 27b is formed flush with the surface of the rib 24 that protrudes laterally (the Z direction shown in Figure 3). Furthermore, the length W3 of the inner surface of the protruding portion 27b (see Figure 4(b)) is approximately equal to the axial length W1 of the first clamp 10 (see Figure 2(a)) (W1 ≈ W3).

The claw portion 27c is a part that is bent inward (in the Z direction shown in Figure 3) from the end of the protruding portion 27b. The claw portion 27c is a part that can be hooked onto the engaging projection 13 of the first clamp 10, and is formed with a protrusion amount approximately equal to the height of the engaging projection 13 (the height of the rising surface 13a).

Furthermore, a tapped hole 28 is formed through the engaging leg portion 27. The tapped hole 28 is a through-hole with internal threads on its inner circumference, and is formed to engage with a bolt 50 (male thread) for fixing the pipe. This tapped hole 28 is positioned to communicate with the first tapped hole 14 when the engaging leg portion 27 engages with the engaging projection 13. This configuration allows the bolt 50, inserted through the tapped hole 28, to pass through the first tapped hole 14 and reach the pipe inserted into the first cylindrical portion 11.

When engaging the second clamp 20 with the first clamp 10, the first clamp 10 is inserted between the pair of engaging legs 27 from the X direction shown in Figure 3. At this time, the protruding direction of the pair of engaging legs 27 and the axial direction of the first cylindrical portion 11 are aligned, and the engaging projection 13 is aligned so that it faces the engaging legs 27. When the first clamp 10 is inserted between the pair of engaging legs 27 in this way, as shown in Figures 7 and 8, the pair of engaging legs 27 embrace the engaging projection 13 from both sides, and the claw portion 27c engages with the engaging projection 13 at the end face of the first clamp 10. Afterward, the two can be fixed together by inserting bolts 50 through the tapped holes 28 in the engaging legs on both sides and fastening them.

As shown in Figures 5 and 6, the third clamp 30 comprises a third cylindrical portion 31 capable of holding the third pipe 57, and a pair of protruding legs 35 formed to protrude from the third cylindrical portion 31. The third clamp 30 in this embodiment is made of metal, for example, aluminum or an aluminum alloy, and is integrally formed (as a single part). Furthermore, the third clamp 30 in this embodiment is manufactured by processing an extruded profile.

The third cylindrical portion 31 is a cylindrical section through which a pipe can be inserted. It has an inner diameter approximately equal to the outer diameter of the pipe (slightly larger than the outer diameter of the pipe, allowing for insertion), in other words, an inner diameter equivalent to that of the first cylindrical portion 11. Four ribs 33 are formed on the outer circumferential surface 31a of this third cylindrical portion 31, at equal intervals when viewed in the circumferential direction. These ribs 33 are rectangular in shape, as shown in Figures 5 and 6, and are formed to protrude radially, perpendicular to the axial direction of the third cylindrical portion 31 (the X direction shown in Figure 5).

As described above, the rib 33 is formed on the outer circumferential surface 31a of the third cylindrical portion 31, making the area where the rib 33 is formed thicker in the radial direction than other areas. A third tapped hole 34 is formed through this thickened portion. The third tapped hole 34 is a through-hole with internal threads on its inner circumference, and is formed to engage with a bolt 50 (male thread) for fixing the pipe. After inserting the pipe into the third cylindrical portion 31, the bolt 50 inserted into the third tapped hole 34 is tightened inward, allowing the tip of the bolt 50 to press down on the pipe inserted into the third cylindrical portion 31. By forming this third tapped hole 34 in the thickened portion, the length of the internal thread (the fastening length of the bolt 50) can be ensured, thereby increasing the fastening force.

Furthermore, an engagement groove 32 is formed on the inner circumferential surface 31b of the third cylindrical portion 31. This engagement groove 32 is for receiving the tenon portion 41 of the sealing material 40 (described later), and is formed along the entire length of the third cylindrical portion 31 in the axial direction. This engagement groove 32 is formed with the same shape and spacing as the engagement groove 12 of the first clamp 10. This engagement groove 32 is positioned so as not to overlap with the rib 33 when the third cylindrical portion 31 is viewed radially.

The protruding leg portion 35 is a plate-shaped portion formed to protrude parallel to the axial direction (the X direction shown in Figure 5) of the third cylindrical portion 31, and is provided to engage with the engaging projection 13 of the first clamp 10 from the outside. These protruding leg portions 35 are provided in pairs, one on each side, and are formed to be continuous with two of the four ribs 33 (those on opposite sides). In this embodiment, the protruding leg portion 35 is a substantially L-shaped portion consisting of a protruding portion 35a and a claw portion 35b.

The protruding portion 35a is a part that extends continuously from the rib 33 and has the same cross-sectional shape as the rib 33. This protruding portion 35a occupies almost the entire protruding leg portion 35 (more than 80% of its total length), and the protruding direction of this protruding portion 35a (the X direction shown in Figure 5) is substantially the protruding direction of the protruding leg portion 35. The length W5 of the inner surface of this protruding portion 35a (see Figure 6(b)) is formed to be approximately equal to the sum of the distance W2 (see Figure 2(b)) from the apex surface 13b of any engaging projection 13 of the first clamp 10 to the rising surface 13a of the engaging projection 13 that protrudes perpendicular to the said engaging projection 13 (however, only the rising surface 13a furthest from the apex surface 13b) and the thickness W4 (see Figure 4(b)) of the engaging leg portion 27 of the second clamp 20 (W2 + W4 ≈ W5).

The claw portion 35b is a part that is bent inward (in the Y direction shown in Figure 5) from the end of the protruding portion 35a. The claw portion 35b is a part that can be hooked onto the engaging projection 13 of the first clamp 10, and is formed with a protrusion amount approximately equal to the height of the engaging projection 13 (the height of the rising surface 13a).

Furthermore, a tapped hole 36 is formed through the protruding leg portion 35. The tapped hole 36 is a through-hole with internal threads on its inner circumference, and is formed to engage with a bolt 50 (male thread) for fixing the pipe. This tapped hole 36 is positioned to communicate with the first tapped hole 14 when the protruding leg portion 35 engages with the engaging projection 13. This configuration allows the bolt 50 inserted through the tapped hole 36 to pass through the first tapped hole 14 and reach the pipe inserted into the first cylindrical portion 11.

When engaging the third clamp 30 with the first clamp 10, the first clamp 10 is inserted between the pair of protruding legs 35 from the Z direction as shown in Figure 5. At this time, the orientation of the pair of protruding legs 35 is aligned so that their protruding directions are perpendicular to the axial direction of the first cylindrical portion 11, and the engaging projection 13 faces the engaging leg 27. When the first clamp 10 is inserted between the pair of protruding legs 35 in this way, as shown in Figures 9 and 10, the pair of protruding legs 35 embrace the engaging projection 13 from both sides, and the claw portion 35b engages with the rising surface 13a of the engaging projection 13. Afterward, the two can be fixed together by inserting bolts 50 through the tapped holes 36 in the protruding legs on both sides and fastening them.

In this embodiment, each clamp member and pipe is connected by bolts 50. The bolts 50 in this embodiment are embedded in tapped holes so as not to protrude from the outer surface of the clamping device. Therefore, the bolts 50 do not protrude from the surface of the clamp, resulting in a safe and aesthetically pleasing design. Any bolt that can be fastened with a wrench can be used as the bolts 50; for example, socket head cap screws can be used.
Next, a method of connecting two pipes in a T-shape using the first clamp 10 and the second clamp 20 described above will be explained with reference to Figures 7 and 8.

When connecting two pipes in a T-shape, first, the first clamp 10 is attached to the outer circumference of the first pipe 55, and the second clamp 20 is attached to the outer circumference of the second pipe 56. That is, as shown in Figure 7, the end of the first pipe 55 is inserted into the first cylindrical portion 11, and the bolt 50 inserted through the first tapped hole 14 is fastened to fix the first pipe 55 to the first clamp 10. Then, the second pipe 56 is inserted through the second cylindrical portion 21, and the bolt 50 inserted through the second tapped hole 25 is fastened to fix the second pipe 56 to the second clamp 20.

Subsequently, the first clamp 10 and the second clamp 20 are engaged with each other, connecting the first pipe 55 and the second pipe 56 in mutually perpendicular directions. Specifically, the pair of engaging legs 27 of the second clamp 20 are engaged with the engaging projection 13 of the first clamp 10 from both sides. At this time, as shown in Figure 8, the U-shaped inner surfaces of the engaging legs 27 engage with the engaging projection 13 on all three surfaces. As a result, the first clamp 10 and the second clamp 20 engage without any play in the four directions: up, down, left, and right.

The first clamp 10 and the second clamp 20, engaged in this manner, are fixed to each other by a bolt 50 inserted from the outside of the engagement leg tapped hole 28. Specifically, the bolt 50 inserted from the outside of the engagement leg tapped hole 28 penetrates the first tapped hole 14 of the first clamp 10 and reaches the first pipe 55. By tightening this bolt 50, the first clamp 10, the second clamp 20, and the first pipe 55 are firmly joined.

Furthermore, in addition to the T-shaped pipes connected as described above, it is also possible to add pipes to connect pipes in the X, Y, and Z directions. The configuration for connecting pipes in three directions will be explained with reference to Figures 9 and 10.
First, connect the two pipes in a T-shape using the same procedure as already explained in Figures 7 and 8.

Furthermore, the third clamp 30 is attached to the outer circumference of the third pipe 57. That is, as shown in Figure 9, the end of the third pipe 57 is inserted into the third cylindrical portion 31, and the bolt 50 inserted through the third tapped hole 34 is fastened to secure the third pipe 57 to the third clamp 30.

Subsequently, the first clamp 10 and the third clamp 30 are engaged with each other, connecting the first pipe 55 and the third pipe 57 in mutually perpendicular directions. Specifically, the pair of protruding legs 35 of the third clamp 30 are engaged with the engaging projection 13 of the first clamp 10 from both sides. At this time, as shown in Figure 10, the L-shaped inner surface of the protruding legs 35 engages by embracing the engaging projection 13, and the end face of the third cylindrical portion 31 abuts against the surface of the engaging leg 27 of the second clamp 20. As a result, the first clamp 10 and the second clamp 20 engage without any play in the four directions: up, down, left, and right.

The first clamp 10 and the third clamp 30, engaged in this manner, are fixed to each other by a bolt 50 inserted from the outside of the tapped hole 36 in the protruding leg. Specifically, the bolt 50 inserted from the outside of the tapped hole 36 in the protruding leg penetrates the first tapped hole 14 of the first clamp 10 and reaches the first pipe 55. By tightening this bolt 50, the first clamp 10, the third clamp 30, and the first pipe 55 are firmly joined.

When the three clamps (first clamp 10, second clamp 20, and third clamp 30) are engaged with each other in this manner, the pair of engaging legs 27 of the second clamp 20 engage with two of the four engaging protrusions 13 of the first clamp 10 that are in opposite positions, and the pair of protruding legs 35 of the third clamp 30 engage with the remaining two engaging protrusions 13. This engagement ensures that the first pipe 55, the second pipe 56, and the third pipe 57 are connected in mutually perpendicular directions.

Furthermore, when the three clamps are engaged with each other, the engaging leg portion 27 (either one) of the second clamp 20 is pressed down by the third cylindrical portion 31 of the third clamp 30. Therefore, combining the clamps improves the holding force.

By the way, the above-described example explained the case where pipes are connected in a T-shape. However, when connecting pipes in an L-shape, a second clamp 20 with the shape shown in Figures 11 and 12 may be used instead of the second clamp 20 shown in Figures 3 and 4. The basic form of the second clamp 20 shown in Figures 11 and 12 is the same as the second clamp 20 shown in Figures 3 and 4, which has already been described, but the difference is that the length of the second cylindrical portion 21 is extended. Specifically, the second clamp 20 shown in Figures 11 and 12 differs from the second clamp 20 shown in Figures 3 and 4 in that it has an extension portion 23 (see Figures 11 and 12) which is an extension of the second cylindrical portion 21. Except for the presence or absence of this extension portion 23, the two are the same shape.

The extension 23 is a portion for attaching the sealing material 40, which will be described later, and is an extension of the second cylindrical portion 21 in the axial direction (the X direction shown in Figure 11). The cross-sectional shape of this extension 23 is the same as that of the second cylindrical portion 21, and is approximately C-shaped. A tapped hole 26 for the sealing material is formed through this extension 23. The tapped hole 26 for the sealing material is a through-hole with internal threads cut on its inner circumference, similar to the second tapped hole 25, and is formed at a position corresponding to the rib 24.

The sealing member 40 inserted into the extension 23 is a cylindrical member as shown in Figures 13 and 14. In this embodiment, the sealing member 40 is made of metal, for example, aluminum or an aluminum alloy. The first clamp 10 in this embodiment is an extruded profile. This sealing member 40 can also be manufactured using materials other than metal, such as synthetic resin or rubber.

A tenon portion 41 is formed protruding from the outer circumferential surface of the sealing member 40. This tenon portion 41 is slidably engaged with the engagement groove 12 formed on the inner circumferential surface 11b of the first cylindrical portion 11, the engagement groove 22 formed on the inner circumferential surface 21b of the second cylindrical portion 21, or the engagement groove 32 formed on the inner circumferential surface 31b of the third cylindrical portion 31. Therefore, the sealing member 40 can be slid into the interior of these clamp members. In this embodiment, an example of inserting the sealing member 40 into the extension portion 23 is described.

The sealing material 40 inserted into the extension 23 is fixed to the extension 23 by a bolt 50. That is, after inserting the sealing material 40 into the extension 23, the bolt 50 inserted into the tapped hole 26 for the sealing material is tightened inward, so that the tip of the bolt 50 presses down on the sealing material 40 that has been inserted into the extension 23.
A method of connecting two pipes in an L-shape using the second clamp 20 having this extension 23 will be described with reference to Figures 15 and 16.

When connecting two pipes in an L-shape, first, the first clamp 10 is attached to the outer circumference of the first pipe 55, and the second clamp 20 is attached to the outer circumference of the second pipe 56. That is, as shown in Figure 15, the end of the first pipe 55 is inserted into the first cylindrical portion 11, and the first pipe 55 is fixed to the first clamp 10 by fastening a bolt 50 inserted through an arbitrary first tapped hole 14. Similarly, the end of the second pipe 56 is inserted into the second cylindrical portion 21, and the second pipe 56 is fixed to the second clamp 20 by fastening a bolt 50 inserted through a second tapped hole 25. Furthermore, a sealing material 40 is inserted into the extension portion 23, and the sealing material 40 is fixed to the second clamp 20 by fastening a bolt 50 inserted through a tapped hole 26 for the sealing material.

Subsequently, the first clamp 10 and the second clamp 20 are engaged with each other, connecting the first pipe 55 and the second pipe 56 in mutually perpendicular directions. Specifically, the pair of engaging legs 27 of the second clamp 20 are engaged with the engaging projection 13 of the first clamp 10 from both sides. At this time, as shown in Figure 16, the U-shaped inner surfaces of the engaging legs 27 engage with the engaging projection 13 on all three surfaces. As a result, the first clamp 10 and the second clamp 20 engage without any play in all four directions: up, down, left, and right.

The first clamp 10 and the second clamp 20, engaged in this manner, are fixed to each other by a bolt 50 inserted from the outside of the engagement leg tapped hole 28. Specifically, the bolt 50 inserted from the outside of the engagement leg tapped hole 28 penetrates the first tapped hole 14 of the first clamp 10 and reaches the first pipe 55. By tightening this bolt 50, the first clamp 10, the second clamp 20, and the first pipe 55 are firmly joined.

Furthermore, as described above, it is possible to add more pipes to the L-shaped pipes and connect them in the X, Y, and Z directions. This embodiment will be explained with reference to Figures 17 and 18.
First, connect the two pipes in an L-shape using the same procedure as already explained in Figures 15 and 16.

Furthermore, the third clamp 30 is attached to the outer circumference of the third pipe 57. That is, as shown in Figure 17, the end of the third pipe 57 is inserted into the third cylindrical portion 31, and the bolt 50 inserted through the third tapped hole 34 is fastened to secure the third pipe 57 to the third clamp 30.

Subsequently, the first clamp 10 and the third clamp 30 are engaged with each other, connecting the first pipe 55 and the third pipe 57 in mutually perpendicular directions. Specifically, the pair of protruding legs 35 of the third clamp 30 are engaged with the engaging projection 13 of the first clamp 10 from both sides. At this time, as shown in Figure 18, the L-shaped inner surface of the protruding legs 35 engages by embracing the engaging projection 13, and the end face of the third cylindrical portion 31 abuts against the surface of the engaging leg 27 of the second clamp 20. As a result, the first clamp 10 and the second clamp 20 engage without any play in the four directions: up, down, left, and right.

The first clamp 10 and the third clamp 30, engaged in this manner, are fixed to each other by a bolt 50 inserted from the outside of the tapped hole 36 in the protruding leg. Specifically, the bolt 50 inserted from the outside of the tapped hole 36 in the protruding leg penetrates the first tapped hole 14 of the first clamp 10 and reaches the first pipe 55. By tightening this bolt 50, the first clamp 10, the third clamp 30, and the first pipe 55 are firmly joined.

As described above, various structures can be constructed by combining the first clamp 10, the second clamp 20, and the third clamp 30. For example, as shown in Figure 19, it is possible to construct a trolley 58 by freely combining pipes.

Furthermore, the trolley 58 shown in Figure 19 has casters 59 attached to its bottom surface. These casters 59 can also be attached using a blocking material 40. Specifically, a through-hole 42 is formed axially inside the blocking material 40 (see Figures 13 and 14). By inserting and fixing the shaft of the caster 59 into this through-hole 42, the caster 59 can be attached to a clamping device (for example, the second clamp 20).

As described above, the clamping device according to this embodiment allows pipes to be connected in mutually perpendicular directions by engaging multiple types of clamps orthogonally. This configuration allows for the creation of a clamping device with a cleaner appearance than typical clamps.

Furthermore, since it does not require integral casting like a key clamp, it is possible to use rust-resistant, inexpensive, and crack-resistant materials (such as aluminum). Therefore, an inexpensive and easy-to-use clamping device can be provided. In particular, using extruded profiles of aluminum or similar materials allows for the provision of an inexpensive and high-quality clamping device.

In this embodiment, the sealing material 40 is attached to the extension portion 23 of the second clamp 20. However, the invention is not limited to this configuration; the sealing material 40 can also be attached to the first cylindrical portion 11 of the first clamp 10, the second cylindrical portion 21 of the second clamp 20, or the third cylindrical portion 31 of the third clamp 30.

Furthermore, the inner circumferential surfaces 11b, 21b, and 31b of the first cylindrical portion 11 of the first clamp 10, the second cylindrical portion 21 of the second clamp 20, and the third cylindrical portion 31 of the third clamp 30 are formed with engagement grooves 12, 22, and 32 that engage with the sealing material 40. The shape of these engagement grooves 12, 22, and 32 can be freely set to match the shape of the tenon portion 41 of the sealing material 40. That is, as long as the shape of the engagement grooves 12, 22, and 32 matches the shape of the tenon portion 41, the shape can be freely changed, not limited to dovetail grooves. Also, if the sealing material 40 does not have a tenon portion 41, the engagement grooves 12, 22, and 32 do not need to be formed.

10 First clamp 11 First cylindrical part 11a Outer surface 11b Inner surface 12 Engagement groove 13 Engagement projection 13a Rising surface 13b Top surface 14 First tapped hole 20 Second clamp 21 Second cylindrical part 21a Outer surface 21b Inner surface 22 Engagement groove 23 Extension part 24 Rib 25 Second tapped hole 26 Tapped hole for sealing material 27 Engagement leg part 27a Expanding part 27b Protruding part 27c Claw part 28 Tapped hole for engagement leg part 30 Third clamp 31 Third cylindrical part 31a Outer surface 31b Inner surface 32 Engagement groove 33 Rib 34 Third tapped hole 35 Protruding leg part 35a Protruding part 35b Claw part 36 Tapped hole for protruding leg part 40 41 Blocking material 42 Tenon 42 Through hole 50 Bolt 55 First pipe 56 Second pipe 57 Third pipe 58 Dolly 59 Caster

Claims (10)

A clamping device for connecting multiple pipes in a direction perpendicular to each other,
A first clamp that can be attached to the outer circumference of the first pipe,
A second clamp that can be attached to the outer circumference of the second pipe,
Equipped with,
The first clamp comprises a first cylindrical portion capable of holding a first pipe, and a plurality of engaging protrusions formed on the outer circumferential surface of the first cylindrical portion.
The second clamp comprises a second cylindrical portion capable of holding a second pipe, and a pair of engaging legs protruding from the second cylindrical portion.
The first pipe and the second pipe are configured to be connectable in directions perpendicular to each other by engaging the pair of engaging legs with the engaging projections on both sides.
Clamping device. The third pipe is further equipped with a third clamp that can be attached to the outer circumference of the third pipe.
The third clamp comprises a third cylindrical portion capable of holding a third pipe, and a pair of protruding legs formed to protrude from the third cylindrical portion.
Four engagement protrusions are formed on the outer circumferential surface of the first cylindrical portion, at equal intervals when viewed in the circumferential direction.
The first pipe, the second pipe, and the third pipe are configured to be connected in mutually orthogonal directions by engaging the pair of engaging legs with two of the four engaging protrusions that are in opposite positions to each other, and engaging the pair of protruding legs with the remaining two engaging protrusions.
The clamping device according to claim 1. The pair of engaging legs are formed to protrude in a direction perpendicular to the axial direction of the second cylindrical portion.
The clamping device according to claim 1. The pair of protruding legs are formed to protrude parallel to the axial direction of the third cylindrical portion.
The clamping device according to claim 2. The second clamp is equipped with a sealing material that can be inserted inside it.
The clamping device according to claim 1. The first clamp and the second clamp are formed from extruded profiles.
The clamping device according to claim 1. The first clamp has a first tapped hole formed through the thickened portion where the engaging projection is formed.
The pipe inserted into the first cylindrical portion is secured by tightening a bolt that is screwed into the first tapped hole.
The clamping device according to claim 1. The first clamp and the second clamp are fixed together by the bolt.
The clamping device according to claim 7. The bolt is embedded in the tapped hole so as not to protrude from the outer surface of the clamping device.
The clamping device according to claim 7 or 8. When the first clamp, the second clamp, and the third clamp are engaged with each other,
The engaging leg of the second clamp is formed to be pressed down by the third cylindrical portion of the third clamp.
The clamping device according to claim 2.