TECHNICAL FIELD
[0001] This invention relates to a clamp used for the connection of steel pipes or the like
for a temporary scaffold and a shelf or the like.
BACKGROUND ART
[0002] A clamp conventionally used in general is structured such that a holding body is
pivotally mounted on one end of a body to be held, a base portion of a clamping bolt
is pivotally mounted on the other end of the holding body, a U-shaped concave portion
is formed on the other end of the body to be held, a tip end portion of the bolt is
fitted in the concave portion, and a nut is screwed onto the bolt to be clamped together.
[0003] In this case, when pipes are assembled parallel or orthogonally to each other, use
has been made of a method of superimposing the bottoms of two clamps back to back
and then riveting two clamps together, or providing a plurality of projections on
the bottom of one clamp, drilling the bottom of the other clamp to give holes to be
correspondingly fitted to the projections, inserting the projections into the holes
and caulking the same for fixing. When pipes are assembled diagonally to each other,
a circular window is provided in the bottoms of both clamps, and a cylinder fitted
to the circular window is freely inserted and caulked so as to use the clamps as a
universal clamp.
[0004] The clamps having the conventional structure involve the problems that since the
concave groove is formed on the tip end of the body to be held, defects in section
are produced to often bring about a lack of strength, and working becomes complicated
and so on.
[0005] In order to solve the problems described above, the present inventors have developed
a clamp as disclosed in Japanese Utility Model Publication No. 57-18507. However,
the present invention provides a further improved clamp structured to pressedly tighten
a body to be held with bolts without providing any bolt insertion hole and to be applicable
to pipes having different dimensions.
[0006] In general, pipes include a circular pipe in cross section and a square pipe in cross
section, and the pipes respectively having two kinds of diameters are often used.
Various clamps are required in combinations of the pipes having the different diameters
with the case of assembling the pipes orthogonally, parallel or diagonally to each
other. The management of these various clamps increases in cost and becomes complicated.
[0007] The present invention is devised in order to solve the problems described above.
DISCLOSURE OF THE INVENTION
[0008] A clamp of the present invention is characterized in that a holding body 1 is pivotally
mounted on one end of a body to be held 4, both base portions of a groove type auxiliary
holding body 10 are pivotally mounted on the other end of the holding body 1, and
a bolt 11 is screwed onto the tip end of the auxiliary holding body 10.
[0009] A spherical tip end portion of the bolt 11 is pressed and fitted to a spherically
concave receiving portion A2 on the outside surface at the other end of the body to
be held 7 in case of using a thick pipe, while being pressed and fitted to a spherically
concave receiving portion A1 on the outside surface at the other end of the body to
be held 4 in case of using a thin pipe, so that the pipe is uniformly pressed and
held by the holding body 1, the body to be held 7 and a hinge portion of the auxiliary
holding body 10.
[0010] Further, in order to constitute an orthogonally universal clamp, a square hole 1a
is bored in the holding body 1, and a circular hole 2a is bored in the holding body
2. Then, a main shaft 3 composed of a square column portion and a cylindrical portion
is inserted into the square hole 1a and the circular hole 2a, and the main shaft 3
and the holding body 1 are rotated as one body by the square column portion of the
main shaft 3, while the holding body 2 is released from the rotation of the main shaft
3 by the cylindrical portion of the main shaft 3. The side of the square column portion
of the main shaft 3 is fixedly attached to the holding body 1, and the other end of
the main shaft 3 constitutes a rotary plate 3a. A pin fit cover member 4 is pivotally
mounted on the holding body 2 with a pin 5.
[0011] When the holding body 1 and the holding body 2 are used as a universal clamp, use
is made under the condition that the pin fit cover member 4 is pushed up to release
the holding body 1 and the holding body 2 from the rotation. When the holding body
1 and the holding body 2 fixed orthogonally or parallel to each other are used, the
pin fit cover member 4 is covered over the rotary plate 3a of the main shaft 3 to
fix the holding body 1 and the holding body 2 for rotation.
BRIEF DESCRIPTION OF THE DRAWINGS
[0012]
Fig. 1(a) is a front view showing an embodiment in case of using circular pipe clamps
combined with each other at right angles;
Fig. 1(b) is a top view of Fig. 1(a);
Fig. 2(a) is a front view showing an embodiment in case of using circular pipe clamps
combined diagonally to each other;
Fig. 2(b) is a top view of Fig. 2(a);
Fig. 3 is a view showing an embodiment applied to a small-diameter circular pipe in
case of welding a nut 13 to a top portion of an auxiliary holding body 10;
Fig. 4(a) is a front view showing an embodiment in case of using square pipe clamps
combined with each other at right angles;
Fig. 4(b) is a top view of Fig. 4(a);
Fig. 5(a) is a front view showing an embodiment in case of using square pipe clamps
combined diagonally to each other;
Fig. 5(b) is a top view of Fig. 5(a);
Fig. 6 is a view showing the operation of a universal clamp;
Fig. 7(a) is a side view showing a main shaft 3 having a square rotary plate 3a;
Fig. 7(b) is a top view of Fig. 7(a);
Fig. 7(c) is a bottom view of Fig. 7(a);
Fig. 8(a) is a view showing a main shaft 3 having a circular rotary plate 3a formed
with a square hole 3d;
Fig. 8(b) is a view showing a pin fit cover member 4 having a square projection 4b
fitted to the square hole 3d;
Fig. 9(a) is a view showing a main shaft 3 having a circular rotary plate 3a formed
with a cross groove 3e;
Fig. 9(b) is a view showing a pin fit cover member 4 having a projection 4e fitted
to the cross groove;
Fig. 10(a) is a view showing a caulking reinforcement washer; and
Fig. 10(b) is a side view of Fig. 10(a).
BEST MODE FOR EMBODYING THE PRESENT INVENTION
[0013] Figs. 1, 2 and 4 show an embodiment in case of using a thick pipe, while Figs. 3
and 5 show an embodiment in case of using a thin pipe, respectively.
[0014] A clamp of the present invention comprises a holding body 1 pivotally mounted on
one end of a body to be held 7 with a pin 8. Both base portions of a groove-type auxiliary
holding body 10 are pivotally mounted on the other end of the holding body 1 with
a pin 9, and a caulking reinforcement member 12 is caulked to form an external thread
at the tip end of the auxiliary holding body 10 or a nut 13 is fixedly attached to
the tip end of the auxiliary holding body 10. A bolt 11 having a spherical tip end
is screwed onto the external thread. Incidentally, the tip end of the auxiliary holding
body 10 may be thickened so that an external thread is formed on the thickened portion
and the bolt 11 is screwed onto the external thread without using the caulking reinforcement
member 12 and the nut 13. Spherically concave receiving portions A1 and A2 are formed
on the outside surface at the other end of the body to be held.
[0015] In case of using the clamp, pipes B1 and B2 are surrounded with the holding body
1 and the body to be held 7, and the tip end of the auxiliary holding body 10 is superimposed
on the body to be held 7.
Subsequently, the bolt 11 is rotated to pressedly fit the tip end of the bolt 11 to
the concave receiving portion A1 or A2 on the outside surface at the other end of
the body to be held.
[0016] Fig. 6 is a view showing the operation of a clamp which is made freely orthogonal.
Hereinafter will be described the operation of the clamp which is made freely orthogonal
with reference to Fig. 6.
[0017] A hole 2a is bored in the holding body 2 of the clamp, and a cylindrical portion
3b of the main shaft 3 is freely inserted into the hole 2a. An octagonal rotary plate
3a is formed at the top of the main shaft. The cylindrical portion 3b extending from
the octagonal rotary plate 3a of the main shaft 3 is inserted into the hole 2a of
the holding body 2. A square column portion 3c extending from the cylindrical portion
3b of the main shaft 3 is inserted into a square hole bored in the holding body 1
and fixedly attached to the holding body 1, and the main shaft 3 is rotated together
with the holding body 1. A pin fit cover member 4 is pivotally mounted on the holding
body 2 with a pin 5.
[0018] In this case, when the main shaft 3 extends through the holding body 1, use may be
made of a caulking reinforcement washer 6.
[0019] Next will be described the operation of a clamp which is used as a freely orthogonal
and parallel clamp.
(a) When the pipes are held diagonally to each other, the clamp is used under the
freely movable condition by pushing up the pin fit cover member 4 to release the rotation
of the holding body 2 and the pin fit cover member 4 from the rotation of the main
shaft 3 and the holding body 1.
(b) When the pipes are held parallel or orthogonally to each other, the clamp is used
under the condition that the rotary plate 3a, thus, the main shaft 3 and the holding
body 1 are fixed parallel or orthogonally to each other by means of a projection 4a
of the pin fit cover member 4 and a projection 2b of the holding body 2 by rotating
the main shaft 3 and the holding body 1 parallel or orthogonally to the holding body
2, and then covering the pin fit cover member 4 on the rotary plate 3a of the main
shaft.
[0020] Fig. 1 shows an embodiment in case of using the circular pipe clamps combined with
each other at right angles. In this embodiment, a caulking reinforcement member 6
is used for the main shaft.
[0021] Fig. 2 shows an embodiment in case of using the circular pipe clamps combined diagonally
to each other. In this embodiment, the caulking reinforcement member is used for the
main shaft.
[0022] Fig. 3 shows an embodiment of clamping a thin circular pipe.
[0023] Fig. 4 shows an embodiment in case of using the square pipe clamps combined orthogonally
to each other. Fig. 5 shows an embodiment in case of using the square pipe clamps
combined diagonally to each other. In either of the embodiments shown in Figs. 4 and
5, any caulking reinforcement member 6 is not used.
[0024] Fig. 6 is a view showing the main shaft 3 having the square rotary plate 3a.
[0025] Fig. 8 shows a combination of the main shaft 3 having the circular rotary plate 3a
formed with the square hole 3d and the pin fit cover member 4 having the square projection
4b fitted to the square hole 3d.
[0026] Fig. 9 shows a combination of the main shaft 3 having the circular rotary plate 3a
formed with a cross groove 3e and the pin fit cover member 4 having the projection
4e fitted to the cross groove.
[0027] Fig. 10 is a view showing the caulking reinforcement washer.
POSSIBILITY OF INDUSTRIAL UTILIZATION
[0028] As has been described above, the clamp of the present invention is provided with
the auxiliary holding body, and the bolt is screwed onto the tip end of the auxiliary
holding body to pressedly fit the spherical tip end of the bolt to the spherically
concave receiving portion on the outside surface at the other end of the holding body.
Thus, it is not necessary to provide any concave groove on the body to be held.
[0029] Therefore, the clamp of the present invention is free from any defect in cross section,
and there is no fear of breakage when used. Further, since the tip end of the bolt
and the concave receiving portion of the body to be held are brought into contact
with each other on their spherical surfaces, there is no problem in rotating and tightening
the bolts.
[0030] Since two concave receiving portions are provided on the body to be held, the clamp
can be applied to pipes having different diameters with safety and security.
[0031] Furthermore, it is possible to reduce the number of combinations of clamps with circular
and square pipes in cross section depending on the size of the pipe diameters, and
the orthogonal, parallel or diagonal assembling of the pipes. Thus, the cost for the
management can be reduced, and the management is simplified.