Clamp

Abstract

[Purpose] A clamp that can be lifted while ensuring safety in particular by setting an iron sill plate in a horizontal state, and can be easily mounted on four corner parts of an iron plate. [Configuration] The clamp comprises: a support housing A, which is composed of an upper surface part 1, a lower surface part 2, and two side surface parts 3 adjacent to each other at right angles, and in which is formed a storage space part 4 having an opening part 42 into which a corner part 91 of an iron sill plate 9 is loosely inserted; and a lifting lever 5 mounted on the support housing A. A closed region part 41 in which a corner part 4a is formed is created in the storage space part 4 of the support housing A. The lifting lever 5 is freely swingable on a vertical plane with the center in the longitudinal direction as a swinging center 51, one-end side in the longitudinal direction as viewed from the swinging center 51 is a pressing end part 52 that withdraws into the support housing A, a withdrawal hole 11 through which the pressing end part 52 withdraws is formed in the upper surface 1, and the other-end side in the longitudinal direction as viewed from the swinging center 51 is a lifting end part 53. With the lifting end part 53 of the lifting lever 5 in a lifted state, the pressing end part 52 can protrude into the support housing A via the withdrawal hole 11.

Description

clamp

[0001] The present invention particularly relates to a clamp that can lift a steel plate while keeping it horizontal and ensuring safety, and that can be easily attached to the four corners of the steel plate.

[0002] Many construction sites, civil engineering sites, and building demolition sites have soft ground, which makes it difficult to carry out construction and civil engineering work safely and also makes it difficult for construction vehicles to travel on. Therefore, steel plates are often laid on the ground to simply reinforce the ground at work sites. These steel plates typically measure 1524mm x 3048mm x 22mm and weigh approximately 802kg.

[0003] When such steel plates are transported to a construction or civil engineering site and installed on the specified ground, or when they are moved or removed, a crane is used to lift the steel plates. Currently, lifting clamps are commonly used for this steel plate lifting work. There are many types of lifting clamps.

[0004] Many conventional clamps (also called lifting tools, suspenders, or slings) are of the type that clamp both sides of a support housing (workpiece), as disclosed in Patent Document 1 (JP Patent Publication No. 9-71384). Specifically, in Patent Document 1, when a steel sheet is to be lifted horizontally, four clamps are provided, and any four points on the steel sheet are clamped between the rotatable cams of the clamps and the fixed receiving surfaces.

[0005] By lifting the wires or chains connected to each clamp, the cams of the four clamps rotate relative to the receiving surface, increasing the clamping pressure on the steel plate by the cams and receiving surface, allowing the steel plate to be lifted horizontally in a firmly clamped state.Patent Document 2 (JP 2011-42441 A) describes a type of clamp equipped with a square, annular holding frame into which the corners of the steel plate can be inserted, allowing the steel plate to be lifted approximately horizontally.

[0006] JP 9-71384 A JP 2011-42441 A

[0007] Incidentally, the work of transporting steel plates to a construction site and installing them on soft ground involves gripping the steel plates transported to the site by truck or other means with a clamp, attaching a chain or wire to the clamp, and then connecting the chain or wire to the hook of a crane, and lifting and lowering the steel plates to install them on the ground.

[0008] Conventional clamps are attached to either the opposing long sides or the opposing short sides of a rectangular steel plate, i.e., to each of four locations on the steel plate, and the steel plate is lifted up and lowered horizontally to install the steel plate transported to the site on the ground at the site.

[0009] In addition, in the past, when lifting a steel sheet by attaching clamps to two points on both sides of one long side or one short side, that is, when lifting the steel sheet with two clamps, the steel sheet was not lifted horizontally but vertically, so with gripping type clamps, if the gripping was not complete and the clamping force was weak, the steel sheet could fall, making the work dangerous and prone to accidents, so this type of work is avoided as much as possible.

[0010] Patent Document 1 discloses a general gripping-type clamp. The clamp clamps both sides of a workpiece (steel plate) between the base bottom and a clamping unit (the name in Patent Document 1). Pulling the wire upward activates the clamping unit, increasing the clamping force on both sides of the workpiece, allowing the workpiece to be lifted. Patent Document 2 discloses a clamping device equipped with a holding frame that supports the four corners of the steel plate in a generally enveloping manner. The four corners of the rectangular steel plate are inserted into the holding frame, and the steel plate can be lifted horizontally by pulling upward on a chain connected to the four holding frames.

[0011] The ground on which steel plates are installed is usually soft and covered with soil or mud, and the steel plates are often installed directly on this ground. In other words, they are placed directly on the ground, which is generally called flat placement. This flat placement of steel plates is easy to install, but because it is placed flat, the underside of the steel plate comes into contact with the ground. Alternatively, because steel plates are extremely heavy (approximately 800 kg), they may sink slightly into the soft surface due to their own weight.

[0012] Therefore, when attaching a clamp to a predetermined location on a steel plate placed flat on the ground, the type of clamp disclosed in Patent Documents 1 and 2 requires the steel plate to be lifted slightly above the ground to create a space between the back of the steel plate and the ground, and part of the clamp must be inserted into that space in order to grasp or hold both sides of the steel plate in a clamping manner.

[0013] In addition, Patent Document 2 describes a clamp having a holding frame that can be inserted into the corner of a steel sheet. However, the vertical dimension of the space in the holding frame for inserting the corner of the steel sheet appears to be approximately equal to the thickness of the corner, and therefore a considerable force must be applied to the holding frame to insert the corner into the holding frame. However, the holding frame disclosed in Patent Document 2 does not appear to have any suitable portion for applying force from the outside, making it extremely difficult to attach the holding frame to the corner of the steel sheet. Therefore, the technical problem to be solved by this invention is to provide a clamp that can be easily attached to the corner of a steel sheet, can be very safely lifted and lowered horizontally, and can easily retrieve a steel sheet laid flat on the ground.

[0014] Therefore, the inventor has conducted extensive research to solve the above-mentioned problems, and as a result, has found that the invention of claim 1 is a support housing which is made up of an upper surface, a lower surface, and both side surfaces which are formed on surfaces adjacent to each other at right angles, and in which a storage space part having an opening in part into which a corner part of a sole plate is loosely inserted, and a lifting lever which is attached to the support housing, and in which the rear part of the storage space part of the support housing as seen from the opening is a rear junction part where the longitudinal ends of the two side surfaces intersect at right angles, and the lifting lever is swung vertically with the longitudinal center part as the swing center. The above problem was solved by providing a clamp that is capable of swinging freely on a surface, one end in the longitudinal direction as viewed from the swing center is a pressing end that protrudes into the support housing, an exit hole is formed in the top surface through which the pressing end protrudes, and the other end in the longitudinal direction as viewed from the swing center is a lifting end, and when the lifting end of the lifting lever is in a lifted state, the pressing end can protrude into the support housing through the exit hole, and a discharge hole is formed in the bottom surface of the support housing near a corner of the rear joining portion.

[0015] The above-mentioned problem is solved by the invention of claim 2, which is the clamp of claim 1, characterized in that the discharge hole is formed in a triangular shape having two sides along both side surfaces at the corners of the rear-side intersecting portion.The above-mentioned problem is solved by the invention of claim 3, which is the clamp of claim 1, characterized in that the discharge hole is formed by excluding the vicinity of the corners of the rear-side intersecting portion of the lower surface.

[0016] The above-mentioned problem is solved by the invention of claim 4, which is the clamp according to claim 1 or 2, characterized in that the upper and lower surface portions of the supporting housing are triangular, the supporting housing is a housing that is triangular in plan view, and the opening is provided on a long side thereof.The above-mentioned problem is solved by the invention of claim 5, which is the clamp according to claim 1 or 2, characterized in that the upper and lower surface portions of the supporting housing are quadrangular, the supporting housing is a housing that is quadrangular in plan view, and the opening is provided along any adjacent both sides.

[0017] The above-mentioned problems are solved by the invention of claim 6, which is the clamp according to claim 1 or 2, characterized in that the pressing end of the lifting lever has a rough surface. The above-mentioned problems are solved by the invention of claim 7, which is the clamp according to claim 1 or 2, characterized in that the outer surface of the rear intersecting portion is an impact portion for use with an impact tool.

[0018] In the inventions of claims 1 to 7, the clamp has a support housing with a storage space formed in part with openings into which the corners of the steel plate can be loosely inserted, and by providing four clamps, the four corners of the rectangular steel plate can be loosely inserted, so that when the steel plate is lifted by a crane, it can be lifted horizontally in an extremely stable state.

[0019] Furthermore, the clamps are equipped with lifting levers, and when the lifting end of the lifting lever is in the lifted state, the pressing end can protrude into the support housing through the recessed hole, so that the corners of the steel plate loosely inserted into the support housing can be firmly fixed during the lifting operation. Furthermore, when the steel plate is lifted while its four corners are supported by the clamps, the four clamps inevitably apply force toward the center of the steel plate's plane via the lifting cables, so that the steel plate can be supported even more firmly, preventing it from falling and allowing for safe lifting operations.

[0020] Furthermore, in the invention of claim 1, a discharge hole is formed on the underside of the support housing near the corner of the rear mixing section, so that soil and mud that has entered the support housing can be discharged through the discharge hole. The discharge of soil and mud that has entered the support housing through the discharge hole can be performed while loosely inserting the corner of the steel plate into the support housing. In other words, as the corner is loosely inserted into the support housing, the corner presses the soil and mud toward the discharge hole inside the support housing, thereby forcing the soil and mud out of the support housing through the discharge hole.

[0021] The clamp of the present invention has a closed area at the rear intermingling portion and a discharge hole, and when loosely inserting the corner of the soleplate into the supporting housing, the closed area at the rear intermingling portion is pressed to allow the corner to be loosely inserted into the supporting housing. Furthermore, even if soil or mud gets into the supporting housing during this loose insertion process, the soil or mud can be discharged out of the supporting housing through the discharge hole as the corner is loosely inserted into the supporting housing, so that the loose insertion of the corner into the supporting housing is not hindered by the soil or mud, and the corner can be accurately inserted and positioned.

[0022] In the invention of claim 2, the drain hole is formed in a triangular shape on the underside, so that the formation of the drain hole can minimize the reduction in strength. In the invention of claim 3, the drain hole can be formed in the support housing very easily. In the invention of claim 4, the size of the clamp can be made compact. In the invention of claim 5, the corners of the steel plate can be supported by the support housing even better. In the invention of claim 6, the corners of the steel plate can be supported by the clamp even more firmly.

[0023] In the invention of claim 7, when retrieving a steel plate laid flat on the ground, the clamp of the present invention has a closed area on the rear side of the clamp centered on the corner of the rear interdigital portion, and this closed area of ​​the rear interdigital portion can be used as a part to be struck with a hammer or the like, and by striking the outer surface of this closed area of ​​the rear interdigital portion with a hammer striking tool, the corner of the steel plate can be easily inserted loosely into the support housing. In other words, with conventional clamps, the steel plate laid flat on the ground had to be lifted even slightly to attach the conventional type clamp, and rafters or the like had to be placed between the steel plate and the ground.

[0024] However, the clamp of the present invention has a closed area at the rear intermingling section that is easy to strike with a hammer, and a discharge hole, so when inserting the corner of the soleplate into the support housing, the closed area at the rear intermingling section can be struck with a hammer to allow the corner to be loosely inserted into the support housing. Furthermore, even if soil or mud gets into the support housing during this loose insertion process, the soil or mud can be discharged out of the support housing through the discharge hole as the corner is loosely inserted into the support housing, so the loose insertion of the corner into the support housing is not hindered by the soil or mud, and the corner can be accurately inserted and positioned.

[0025] (A) is a perspective view of the clamp of the present invention, (B) is a plan view of the clamp, (C) is a cross-sectional view taken along the X1-X1 arrow in (A), and (D) is a cross-sectional view taken along the X2-X2 arrow in (B). (A) is a perspective view of only the support housing excluding the lifting lever mechanism, (B) is a perspective view of the support housing excluding the top surface, (C) is an enlarged view of part (α) in (B), (D) is an enlarged view of part (α) in (B) in another embodiment, and (E) is a perspective view of the support housing excluding the top surface in another embodiment. (A) is a perspective view of a steel sheet being lifted by the clamp of the present invention, (B) is an enlarged view of part (β) in (A), and (C) is an enlarged view of part (β) in (A) in another embodiment. (A) is an enlarged perspective view of a main part with a portion cut away, showing a steel plate being lifted with the clamp of the present invention; (B) is an enlarged view of part (γ) of (A); and (C) is an enlarged view of part (γ) of (A) with the clamp and the corner of the steel plate separated. (A) is a plan view of a steel plate being lifted with the clamp of the present invention; (B) is a side view of a steel plate being lifted with the clamp of the present invention. (A) to (C) are longitudinal side views showing the process of lifting the corner of a steel plate with the clamp of the present invention. (A) is a schematic view showing the process of attaching the clamp of the present invention to a steel plate placed flat on the ground; (B) is a perspective view showing the process of attaching the clamp of the present invention to a steel plate placed flat on the ground. (A) to (E) are longitudinal side views showing the process of attaching the clamp of the present invention to a steel plate placed flat on the ground. 1A is a perspective view of another embodiment of the clamp of the present invention, FIG. 1B is a plan view of another embodiment of the clamp of the present invention, and FIG. 1C and FIG. 1D are longitudinal side views showing embodiments of the roughened surface shape of the pressing end of the lifting lever.

[0026] An embodiment of the present invention will be described below with reference to the drawings. While the term "clamp" is used herein, clamps are also commonly referred to as lifting devices, suspending devices, or slings, and these are also included in the concept of a clamp. The clamp of the present invention comprises a support housing A and a lifting lever mechanism B (see FIG. 1). The support housing A comprises an upper surface 1, a lower surface 2, and two side surfaces 3 formed at right angles (or corners), all of which are made of metal plate material (see FIGS. 1 and 2). In the present invention, the upper surface 1, the lower surface 2, and both side surfaces 3 each have a thickness of approximately 6 mm. However, this is not a limitation, and the thickness may be changed as appropriate depending on the application.

[0027] The upper surface portion 1 and the lower surface portion 2 are arranged parallel to each other at a predetermined interval in the vertical direction, and two side surface portions 3 are arranged between the upper surface portion 1 and the lower surface portion 2 and along the outer peripheries of the upper surface portion 1 and the lower surface portion 2, and these are fixed to each other by a fixing means such as welding. In this way, a housing having a storage space portion 4 with an opening portion 42 formed in a part thereof is formed, and this housing becomes the supporting housing A. The corner portion 91 of the iron plate 9 is loosely inserted into the storage space portion 4 of the supporting housing A (see FIG. 6).

[0028] Here, loose insertion refers to a state in which the insole can be inserted with some leeway, and specifically, it can be inserted so that there is some leeway around the corners 91 of the insole plate 9 in the storage space 4. However, when the corners 91 of the insole plate 9 are completely stored, the periphery of the corners 91 comes into contact with the side surface 3 of the supporting housing A, and by operating the lifting lever B, which will be described later, the corners 91 of the insole plate 9 are firmly fixed to the supporting housing A without any gaps.

[0029] Since the corners 91 of the iron plate 9 can be inserted loosely into the storage space 4 through the opening 42 of the supporting housing A, the vertical dimension of the opening 42 is formed to be slightly larger than the thickness of the corners 91 of the iron plate 9. In other words, the distance between the upper surface 1 and the lower surface 2 of the supporting housing A is set to be larger than the thickness of the corners 91 of the iron plate 9 to allow some leeway. Specifically, the thickness of the iron plate 9 is about 22 mm, and the distance between the upper surface 1 and the lower surface 2 of the supporting housing A is about 40 mm. Therefore, the distance between the upper surface 1 and the lower surface 2 of the supporting housing A, i.e., the vertical dimension of the opening 42, is about 1.3 to 2 times the thickness of the corners 91 of the iron plate 9 (see FIG. 6).

[0030] A corner 4a is formed at the rear side of the storage space 4 of the support housing A as viewed from the opening 42, where two side surfaces 3, 3 are adjacent to each other at a right angle (see FIG. 2). The rear portion of the storage space 4 is a closed space surrounded by the upper surface 1, the lower surface 2, and the side surfaces 3, 3 that form wall surfaces on both sides of the corner 4a, and the closed space centered on the corner 4a, including the corner 4a and its surroundings, is referred to as a closed area 41.

[0031] However, the closed area 41 has a discharge hole 21, which will be described later, and the area excluding the discharge hole 21 is a closed space. The corners 91 of the sole plate 9, which is loosely inserted into the storage space 4 of the supporting housing A through its opening 42, abut against the corners 4a of the closed area 41 on the rear side of the supporting housing A and both side surfaces 3, 3, and are embraced by the closed area 41 of the supporting housing A. The corners 4a are the areas where the longitudinal ends of the two side surfaces 3 meet at a right angle.

[0032] The structure where the ends of the two side portions 3 intersect is such that the ends of both side portions 3, 3 are flat surfaces that are perpendicular to the longitudinal direction, and the end face of one side portion 3 abuts against the other side portion 3 and is fixed by welding or the like (see Fig. 2(C)).Also, in another structure where the ends of the two side portions 3 intersect, the end faces of both side portions 3, 3 are formed as inclined surfaces at an angle of 45°, and the inclined end faces abut against each other and are fixed by welding or the like (see Fig. 2(E)).

[0033] The support housing A is a triangular housing when viewed from above. Because the support housing A is triangular, the upper surface portion 1 and the lower surface portion 2 are both identically triangular, specifically, right-angled triangles (see FIGS. 1(A), 1(B), and 2(A)). The long sides of the right-angled triangles of the upper surface portion 1 and the lower surface portion 2 are arranged so that they correspond to each other, and an opening 42 is provided between the two long sides (see FIGS. 1(A), 1(C), 1(D), and 2(A)). The upper surface portion 1 of the support housing A has an outlet hole 11 (see FIGS. 1(D) and 2(A)). The outlet hole 11 is formed as a substantially rectangular elongated hole, and serves as the portion through which the pressing end 52 of the lifting lever 5 of the lifting lever mechanism B, described later, appears and disappears.

[0034] A discharge hole 21 is formed in the underside 2 of the support housing A near the corner 4a (see FIGS. 1(C), 1(D), 2(B), and 2(C)). When foreign matter such as soil or sand from the ground gets into the storage space 4 of the support housing A, the discharge hole 21 serves to discharge the foreign matter from the discharge hole 21 to the outside of the support housing A when the iron plate 9 is loosely inserted into the storage space 4. As described above, the discharge hole 21 is provided near the corner 4a and is triangular, specifically, a right triangle having two sides that run along both side surfaces 3, 3 of the corner 4a. The size (e.g., area) of the discharge hole 21 is determined based on the expected amount of foreign matter to be discharged, and is also determined according to the size of the gravel that may be mixed in with the foreign matter.

[0035] There is also an embodiment in which the discharge hole 21 is formed by excluding the corners 4a of the bottom surface 2 of the supporting housing A (see FIG. 2(E)). Specifically, the bottom surface 2 is trapezoidal, and the openings formed between the short upper side and the two side surfaces 3, 3 adjacent at right angles are used as the discharge hole 21. The discharge hole 21 of this embodiment has the advantage that it is possible to omit the step of previously drilling a through hole for the discharge hole 21 in the bottom surface 2.

[0036] Next, the lifting lever mechanism B comprises a lifting lever 5 and a swing support part 6 (see Figure 1). The lifting lever 5 operates in a roughly balance-like manner, with a swing center part 51 formed at the center in the longitudinal direction of the lifting lever 5, with one longitudinal end side as viewed from the swing center part 51 being a pressing end part 52 and the other end side being a lifting end part 53. The swing center part 51 is actually a through-hole, and is the part through which the shaft part of a bolt part 62a constituting the swing support part 6, which will be described later, is inserted.

[0037] The pressing end 52 appears and disappears into the storage space 4 through the inlet and outlet holes 11 in the top surface 1, and when lifting, the pressing end 52 presses against the corners 91 of the sole plate 9 loosely inserted into the storage space 4 to create a pressing state. The lifting end 53 is a part that is connected to a cable material 8 such as a chain or wire when the clamp of the present invention is lifted by a crane, and has a connection hole 53a formed therein. The swing support part 6 is composed of a swing base 61 and a swing shaft part 62 (see Figure 1).

[0038] The oscillating base 61 is disposed on the outer surface of the upper surface 1 and oscillates the lifting lever 5 via an oscillating shaft 62. The oscillating shaft 62 is composed of a bolt 62a, a nut 62b, and a washer 62c. The two oscillating bases 61 are disposed parallel to each other at a predetermined distance so as to sandwich the width direction of the access hole 11 in the upper surface 1, and are fixed to the top surface 1 by a fixing means such as welding. A shaft hole 61a is formed in each oscillating base 61, through which the shaft portion of the bolt 62a passes.

[0039] The lifting lever 5 is disposed between the two oscillating bases 61, and a bolt 62a passes through the shaft hole 61a of the oscillating base 61 and the hole in the oscillating center 51 of the lifting lever 5, and a washer 62c and a nut 62b are fastened to the bolt 62a. This allows the lifting lever 5 to oscillate on a vertical surface above the top surface 1, and the pressing end 52 extends and retracts through the retraction hole 11 so as to protrude into the storage space 4 of the support housing A. A cable 8 such as a chain or wire is connected to the connection hole 53a of the lifting end 53.

[0040] When the lifting lever 5 is in a lifted state pulled up by the cable 8 of its lifting end 53, the pressing end 52 can protrude into the support housing A through the recessed hole 11. More specifically, in an unloaded state, the pressing end 52 of the lifting lever 5 is located outside the top surface 1, and when the lifting end 53 of the lifting lever 5 is pulled up by the cable 8, the pressing end 52 enters and protrudes from the recessed hole 11 of the top surface 1 into the storage space 4 inside the support housing A (see FIG. 6(B)).

[0041] Next, the process of lifting the steel sheet 9 using the clamp of the present invention will be described. First, a total of four clamps of the present invention are prepared (see Figures 3(A) and 4(A)). Then, the four corners 91 of the steel sheet 9 are loosely inserted into the storage space 4 through the opening 42 of the support housing A of the clamp (see Figures 4(C) and 6(A)). At this time, the pressing end 52 of the lifting lever 5 is not in a state where it presses against the corners 91 of the steel sheet 9.

[0042] After the clamps are attached to the four corners 91 of the steel plate 9, the lifting end 53 of the lifting lever 5 is lifted upward by a crane using a cable 8 such as a chain or wire connected to the lifting end 53 of the lifting lever 5. This causes the lifting lever 5 to swing around the swing center 51 as the swing center, causing the pressing end 52 to drop downward (see Figures 4(B) and 6(B)). Furthermore, the pressing end 52 protrudes from the outlet hole 11 into the storage space 4 and presses the corners 91 of the steel plate 9 stored in the storage space 4 with a pressing force P, so that the corners 91 are sandwiched and pressed between the pressing end 52 and the underside 2 (see Figure 6(C)). The pressing force P of the pressing end 52 against the corners 91 of the steel plate 9 increases as the weight of the steel plate 9 increases.

[0043] The steel plate 9 can be lifted horizontally by using a crane to simultaneously lift the four clamps together with the cable 8 (see Figure 3(A)). At this time, the four clamps attached to the four corners 91 of the steel plate 9 have their respective cables 8 connected to the crane hook or the like in a convergent manner (see Figures 3(B), 3(C), 4, etc.). Therefore, the four clamps generate a force F toward the center of the steel plate 9 (see Figures 5 and 6(C)). The four forces F acting on the four clamps act equally on the four corners 91 of the steel plate 9. Furthermore, because the corners 91 are enclosed within the storage space 4 of the support housing A, the steel plate can be lifted and transported in an extremely stable and secure manner (see Figure 4(A)). A shackle may be provided between the cable 8 and the crane hook, and the rings at the upper ends of the four cables 8 may be connected together to a single shackle (see Figure 3(C)).

[0044] Next, the process of removing the steel plate 9 installed on the ground G will be explained with reference to Figures 7 and 8. First, the ground G at a construction site is generally made of soil or the like, and is a soft surface that can become muddy due to rainfall, etc. Furthermore, the steel plate 9 is extremely heavy, and is in close contact with the surface of the ground G. In other words, there is almost no space between the steel plate 9 and the ground G (see Figure 7(A) (I) and Figure 8(A)).

[0045] In such a case, when lifting the steel plate 9 for the purpose of retrieving it, with a conventional clamp, a tool such as a crowbar is used as a lever to partially lift the steel plate 9 off the ground G, creating a space between the steel plate 9 and the ground G, and this space is used to attach the conventional clamp. Furthermore, in order to maintain this space between the steel plate 9 and the ground G, rafters or the like must be prepared.

[0046] In the clamp of the present invention, a worker shallowly excavates a depression k in the ground G on which the steel sole plate 9 is laid and around the corner 91 of the steel sole plate 9. The depth of this depression k need only be very small, approximately the thickness of the underside 2. Furthermore, as mentioned above, the ground G is soft, so the worker can easily excavate it with a handheld shovel or spade. The clamp of the present invention is then placed in the excavated depression k, with the opening 42 facing the corner 91 (see (II) and (III) of Figure 7(A) and Figure 8(B)). Then, the worker strikes the clamp with a striking tool T, such as a hammer (see (IV) of Figure 7(A)), at the point where the two side surfaces 3, 3 of the clamp's support housing A intersect, i.e., from the outside of the corner 4a, to attach the corner 91 of the steel sole plate 9 to the support housing A.

[0047] At this time, soil and mud from the ground G may get into the storage space 4 of the support housing A (see FIG. 8(C)). However, as the corner 91 is loosely inserted into the storage space 4, the soil and mud can be pushed toward the corner 4a (see FIG. 8(D)), and the soil and mud can be discharged through the discharge holes 21 provided in the underside 2 (see FIG. 8(E)). Furthermore, soil and mud that has accumulated in the storage space 4 of the support housing A can be removed by hand by an operator, but it can also be easily and instantly discharged to the outside of the support housing A through the discharge holes 21 by simply spraying water from a water hose into the opening 42, using water pressure.

[0048] As a result, the entire corner 91 of the insulator plate 9 enters the storage space 4 of the support housing A and comes into contact with the corner 4a and both side surfaces 3, allowing the clamp to be securely attached to the corner 91 (see Figure 7(B)). Also, the support housing A has a closed area 41 on the far side as seen from the opening 42, and both side surfaces 3 are adjacent to each other, so the shape is suitable for an operator to drive in with a striking tool T such as a hammer (see Figure 7(A) (IV) and (B)).

[0049] In a second embodiment of the present invention, the upper surface 1 and the lower surface 2 of the support housing A are rectangular, and the support housing A is a rectangular housing when viewed from above, and openings 42 may be provided along any two adjacent sides (see Figures 9(A) and (B)). In this embodiment, the closed area 41 is the area where two adjacent sides of the upper surface 1 and the lower surface 2 directly abut against both side surfaces 3, 3.

[0050] The portions of the upper surface 1 and the lower surface 2 that do not abut against the side surface portions 3, 3 become part of the upper surface 1 and the lower surface 2, and become portions that protrude horizontally from the opening 42. By making the portions of the upper surface 1 and the lower surface 2 that protrude from the opening 42 upper auxiliary support plate 1a and lower auxiliary support plate 2a, the support housing A in the second embodiment can support the corner portion 91 of the insulator plate 9 even more firmly.

[0051] The pressing end 52 of the lifting lever 5 may have a roughened surface 52a. The roughened surface 52a may be sawtooth (see FIG. 9C) or knurled with repeated indentations (see FIG. 9D). By providing the roughened surface 52a on the pressing end 52, the corners 91 of the insulator plate 9 housed in the support housing A can be firmly fixed by the lifting lever 5.

[0052] A...support housing, 1...upper surface portion, 11...inlet / outlet hole, 2...lower surface portion, 21...discharge hole, 3...side portion, 4...storage space portion, 4a...corner portion, 41...closed area portion, 42...opening portion, B...lifting lever mechanism portion, 5...lifting lever, 51...swing center portion, 52...pressure end portion, 53...lifting end portion, 6...swing support portion, 9...iron plate, 91...corner portion.

Claims

1. A support housing is provided with a storage space having an opening into which the corners of a steel sheet are inserted, the storage space being formed with an upper surface, a lower surface, and both side surfaces arranged perpendicularly to each other, and a lifting lever is attached to the support housing. The rear part of the storage space of the support housing as viewed from the opening is a rear joining part where the longitudinal ends of the two side surfaces join at a right angle, and the lifting lever is freely swingable on a vertical surface with the longitudinal center part as the swing center, and the front The clamp is characterized in that one end side in the longitudinal direction as viewed from the swing center is a pressing end portion that protrudes into the support housing, a hole is formed in the top surface portion through which the pressing end portion protrudes, and the other end side in the longitudinal direction as viewed from the swing center is a lifting end portion, and when the lifting end of the lifting lever is in a lifted state, the pressing end portion can protrude into the support housing through the hole, and a discharge hole is formed in the bottom surface portion of the support housing near a corner of the rear mixing portion.

2. A clamp as described in claim 1, characterized in that the discharge hole is formed in a triangular shape having two sides that run along both side surfaces at the corners of the rear joining portion.

3. A clamp as described in claim 1, characterized in that the discharge hole is formed by excluding the corner portion of the rear joining portion of the lower surface.

4. A clamp as claimed in claim 1 or 2, characterized in that the upper and lower surfaces of the supporting housing are triangular in shape, the supporting housing is a triangular housing when viewed from above, and the opening is provided on the long side thereof.

5. A clamp as claimed in claim 1 or 2, characterized in that the upper and lower surfaces of the supporting housing are rectangular in shape, the supporting housing is a rectangular housing when viewed from above, and the openings are provided along any adjacent two sides.

6. A clamp as claimed in claim 1 or 2, characterized in that the pushing end of the lifting lever is roughened.

7. A clamp as claimed in claim 1 or 2, characterized in that the outer surface of the rear intermingling portion is adapted to be an impact portion to be struck by an impact tool.

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