JP4429052B2 - Screw clamp - Google Patents

Description

  The present invention relates to a screw clamp.

  FIG. 8 shows an example of a conventional configuration of a screw clamp. A receiver 42 is supported on one leg 41 of the clamp body 40, and a fastening bolt 44 is supported on the other leg 43, and a suspended load (between the receiver 42 and the fastening bolt 44 ( The clamping bolt 44 is rotated by operating the handle 45 in a state where the not shown is sandwiched, and the suspended load is pressed and clamped to enable lifting by a crane (not shown) or the like.

  The receiver 42 is supported by a spherical bearing 46 embedded and fixed in the leg portion 41 so as to be rotatable and swingable, and a coil spring 47 mounted between the open end of the leg portion 41 is provided. It is possible to move backward slightly from the illustrated position against the spring force.

  Further, the pressure nut 48 mounted in the leg portion 43 is not rotatable relative to the leg portion 43, and resists the spring force of the coil spring 49 disposed on the outer periphery of the pressure nut 48 from the illustrated position. It is possible to move slightly backward in the axial direction. Further, the pressure nut 48 is screwed with the tightening bolt 44.

  The coil spring 47 is designed to have a smaller spring force than the coil spring 49.

  With the above configuration, when the tightening bolt 44 is further tightened from the state in which the suspended load is received and clamped between the clamp 42 and the clamp bolt 44, the receiver 42 first resists the spring force of the coil spring 47. Then, when the clamping bolt 44 is tightened after the catcher 42 has moved to the innermost position, the pressure nut 48 resists the spring force of the coil spring 49. It moves backward in the direction to be buried in the leg 43.

An example of such a conventional screw-type clamp is described in Patent Document 1 below.
JP 2002-205279 A (FIG. 11).

  When the suspended load to be lifted by the screw type clamp is a grooved steel or I-shaped steel, the sloped surface of the suspended load is sandwiched between the receiving metal 42 and the fastening bolt 44. . Since the receiver 42 is supported by the spherical bearing 46 as described above and is swingable, when the inclined surface of the suspended load is sandwiched between the receiver 42 and the fastening bolt 44 and lifted, Inclined at the same angle as the inclination angle of the gradient surface.

  For example, as shown in FIG. 9, when the clamp 51 is lifted with an external crane or the like by sandwiching the side surface 51 of the grooved steel 50 between the receiver 42 and the fastening bolt 44, the frictional force due to the initial load and the grooved steel With the suspension load of 50, the receiving metal 42 is swung and inclined by the same angle as the inclination angle (for example, 5 degrees) of the side surface 51, and the clamping force is generated.

  Further, as shown in FIG. 10, when the clamp surface is lifted with an external crane or the like by sandwiching the flange surface 53 of the I-shaped steel 52 between the receiving metal 42 and the fastening bolt 44, the frictional force due to the initial load and the I-shaped steel Due to the suspension load of the steel 52, the receiving metal 42 is inclined by the same angle as the inclination angle (for example, 8 degrees) of the flange surface 53, and a clamping force is generated.

  By the way, the receiver 42 is supported by the spherical bearing 46 as described above and can swing freely, but the maximum inclination angle is generally set to about 10 to 15 degrees. Assuming that the maximum inclination of the receiver 42 is 10 degrees, the flange surface 53 of the I-shaped steel 52 having an inclination angle of 8 degrees is sandwiched between the receiver 42 and the fastening bolt 44 as shown in FIG. When the clamp is lifted by an external crane or the like, the catch 42 also tilts by 8 degrees, leaving only a margin of 2 degrees for the tilt angle. When lifting a clamp holding a suspended load with an external crane, etc., it may cause work or reversal work, and impact load may also act. In such a case, it is necessary to tilt the clamp more greatly However, since the maximum inclination of the receiver 42 is exceeded, the inclination until the receiver 42 sufficiently bites into the suspended load cannot be given to the clamp. For this reason, a clamping force proportional to the suspended load is not generated, and there is a risk that the suspended load slips and falls.

  Further, if the inclined surface of the suspended load is directly clamped by the tightening bolt 44, slippage in the rotational direction of the tightening bolt 44 occurs between the tip of the tightening bolt 44 and the inclined surface, and the clamp is suspended. It is difficult to attach the load to the load, and the entire clamp is attached at an angle, which impairs safety.

  Therefore, the problem to be solved by the present invention is to lift safely and reliably even when a sloped surface such as a grooved steel or I-shaped steel is sandwiched between a fastening bolt and a receiving metal. It is an object of the present invention to provide a screw-type clamp having a novel configuration.

In order to solve this problem, the present invention according to claim 1 includes a generally U-shaped clamp body having a pair of legs facing each other across an opening, and a receiver attached to one leg so as to be relatively movable. And a fastening bolt that is screwed to the other leg portion and is capable of moving back and forth in the axial direction, and lifts in a state where the suspended load inserted into the opening is pressed and clamped between the clamp and the fastening bolt. In the screw-type clamp, a gradient pad having a tip surface inclined at a predetermined angle with respect to a surface perpendicular to the axis of the tightening bolt is attached to the tip of the tightening bolt so as to be rotatable relative to the tightening bolt , and A rotation restricting means for restricting the rotation of the gradient pad and maintaining the tip end face in the inclined state at the predetermined angle when the tightening bolt rotates and advances and retreats with respect to the opening is provided. this is bridged between The features.

The present invention according to claim 2, in the screw clamp according to claim 1, characterized in that the slope pad is detachably attached to the distal end of the fastening bolt.

According to a third aspect of the present invention, in the screw type clamp according to the first or second aspect , the rotation restricting means comprises a pair of guide bars sandwiching the clamp body and a guide plate that is not relatively rotatable with the gradient pad. Features

  According to the screw-type clamp of the present invention, the gradient pad having the tip surface inclined at a predetermined angle with respect to the surface perpendicular to the axis of the fastening bolt is attached to the tip of the fastening bolt so as not to be relatively rotatable. The gradient pad does not rotate during the axial movement caused by the rotation of the clamping bolt, but only slides in the axial direction of the clamping bolt with respect to the clamp body. Even when the inclined surface is clamped between the receiving metal and the inclined pad, the inclination of the inclined surface of the suspended load is offset by the inclination of the front end surface of the inclined pad, and the clamp is maintained substantially vertical. In addition, when the inclined surface of the suspended load is tightened by rotating the tightening bolt, the gradient pad does not slip in the rotational direction, so that the clamp can be easily and reliably attached to the suspended load having the inclined surface.

  In addition, since the catcher and the gradient pad can sufficiently penetrate the sloping surface of the suspended load, a clamping force proportional to the suspended load is generated, and there is no risk that the suspended load will slip and fall. Work such as lifting, transporting and hanging safely can be performed.

  FIG. 1 shows an embodiment of a screw clamp according to the present invention. The screw-type clamp 10 has an opening 14 for inserting a suspended load (not shown) between a pair of legs 12 and 13 of a substantially U-shaped clamp body 11. The clamp main body 11 is provided with two suspension ring portions 35 and 36 to enable lifting in two directions.

  On one leg portion 12, a receiver 15 is attached so as to be rotatable, swingable, and reciprocally movable. The receiver 15 is always urged by the coil spring 16 in a direction in which it protrudes toward the opening 14. The receiver 15 is supported by a spherical bearing 17 disposed in the leg portion 12 so as to be rotatable and swingable. Engaging teeth 18 such as a ring shape are formed on the front end surface of the catch 15 in order to increase the frictional force with respect to the suspended load holding surface.

  A fastening bolt 20 is attached to the other leg portion 13 so as to freely advance and retract. The fastening bolt 20 is provided with a male screw 21 which is screwed into a female screw (not shown) formed through the leg portion 13 on the outer peripheral surface, and a split ring-shaped ser formed of an elastic material at the tip thereof. The pad 23 is detachably mounted while being prevented from being removed by the clip 22. Engagement teeth 24 such as a knurled shape are formed on the front end surface of the pad 23 in order to increase the frictional force with respect to the suspended load holding surface. A handle 25 is provided at the rear end of the tightening bolt 20, and when the handle 25 is turned, the tightening bolt 20 advances and retreats in the axial direction, and the pad 23 moves toward or away from the receiving metal 15.

  The pressure nut 26 mounted in the leg portion 13 is not rotatable relative to the leg portion 13 and from the position shown in the figure against the spring force of the coil spring 27 disposed on the outer periphery of the pressure nut 26. It is possible to move slightly backward in the axial direction. The coil spring 27 is designed to have a larger spring force than the coil spring 16. Since the operation of the pressure nut 26 is the same as that described above with respect to the prior art, the description thereof is omitted.

A major feature of the screw-type clamp 10 is the pad 23 attached to the tip of the fastening bolt 20. The pad in the conventional screw-type clamp has a tip surface on a plane generally orthogonal to the axis of the fastening bolt, and is attached so as to be rotatable relative to the fastening bolt. As shown in FIG. 3, the pad 23 in the screw-type clamp 10 has a predetermined inclination with respect to a plane Y in which the tip surface X on which the engagement teeth 24 are formed is orthogonal to the axis of the fastening bolt 20. The rotation angle is controlled so that the direction of the predetermined inclination angle θ is maintained even if the tightening bolt 20 moves forward and backward by a guide plate 31 described later. The inclination angle θ of the gradient pad 23 is for matching with the gradient surface of a suspended load such as a grooved steel or I-shaped steel, and is arbitrarily set, for example, within a range of about 5 to 10 degrees.

  The rear end side of the gradient pad 23 is a substantially cylindrical shaft portion 28, and is fitted in the annular groove 29 in a state where the gradient pad 23 is fitted in the fitting recess 34 provided at the tip of the fastening bolt 20. The circlip 22 is attached so as not to be detached. The shaft portion 28 and the gradient pad 23 are integrally processed into a substantially rectangular shape 30. The fitting recess 34 includes a distal-side small-diameter portion (not shown) having an inner diameter substantially the same as the outer diameter of the shaft portion 28 of the gradient pad 23 and a rear-side large-diameter portion (reference number) having an inner diameter slightly larger than the distal-side small-diameter portion. None), and a stepped portion (no reference) is provided between the tip side small diameter portion and the back side large diameter portion.

  A guide plate 31 mounted between the gradient pad 23 and the fastening bolt 20 has a shape as shown in FIG. 4 and includes a substantially rectangular opening 32 and a pair of guide bars 33 and 33. ing. The rectangular opening 32 is formed in a shape and size capable of fitting the substantially rectangular portion 30 described above. Further, as shown in FIG. 5, the pair of guide bars 33, 33 protrude with an interval of a dimension substantially the same as or slightly larger than the thickness dimension of the portion facing the opening 14 of the clamp body 11.

  When attaching the gradient pad 23 and the guide plate 31, the guide pad 31 is positioned so that the pair of guide bars 33, 33 have an angular position between which the clamp body 11 is sandwiched, and the gradient pad 23 is inserted into the rectangular opening 32 of the guide plate 31. Are fitted together, and in this state, the shaft portion 28 is fitted halfway into the fitting recess 34 at the tip of the fastening bolt 20, and the fastening bolt 20 is tightened by operating the handle 25. Rotate in the direction. As described above, since the gradient pad 23 is kept non-rotatable via the guide plate 31, the predetermined inclination angle θ is maintained. As the clamping bolt 20 advances, the gradient pad 23 hits the catch 15 and when the clamping bolt 20 is further advanced, the circlip 22 partially protruding from the shaft portion 28 is elastically applied to the clamping bolt 20. The diameter is reduced by hitting the distal end side small diameter portion of the fitting concave portion 34, and it is pushed into the annular groove (not indicated) of the shaft portion 28 and accommodated. When the shaft portion 28 is pushed to a predetermined depth, the circlip 22 exceeds the above-described step portion (the step portion between the tip side small diameter portion and the back side large diameter portion of the fitting recess 34) and the back side large diameter portion. Therefore, the diameter is restored to normal and expanded. Thus, the gradient pad 23 is mounted so as not to fall off, and the guide plate 31 is also mounted while being sandwiched between the fastening bolt 20 and the gradient pad 23. As described above, since the gradient pad 23 is kept non-rotatable via the guide plate 31, the predetermined inclination angle θ of the gradient pad 23 is maintained even during the attaching operation.

  With the above configuration, the gradient pad 23 attached to the tip of the tightening bolt 20 is not rotatable via the guide plate 31. Therefore, even if the tightening bolt 20 is rotated through the operation of the handle 25 and moved forward or backward with respect to the clamp opening 14, the gradient pad 23 does not rotate, and the tip surface X thereof becomes the orthogonal plane Y. On the other hand, while maintaining a predetermined inclination angle θ, it slides relative to the clamp body 11 together with the guide plate 31 as the clamping bolt 20 moves in the axial direction.

  FIG. 6 is a state diagram when the grooved steel 50 is lifted using the screw type clamp 10, and the side surface 51 of the grooved steel 50 is sandwiched between the metal 15 and the gradient pad 23. FIG. 7 is a state diagram when the I-shaped steel 52 is lifted using the screw type clamp 10, and the side surface 53 of the I-shaped steel 52 is sandwiched between the metal 15 and the gradient pad 23. .

  In any case, since the gradient pad 23 has the inclination θ corresponding to the inclination of the side surfaces 51 and 53 as described above, the clamp 10 is maintained substantially vertical even when the side surfaces 51 and 53 are sandwiched. Further, the guide plate 31 cannot be rotated by arranging the pair of guide bars 33 and 33 so as to sandwich the clamp body, and the substantially rectangular portion 30 of the gradient pad 23 is formed in the square opening 32 of the guide plate 31. Since the gradient pad 23 cannot be rotated by the fitting, the gradient pad 23 does not slip in the rotational direction when the clamping bolt 20 is rotated to tighten the gradient surfaces 51 and 53 of the suspended loads 50 and 52. It can be easily and reliably attached to a suspended load having a sloped surface.

  In addition, since the receiver 15 and the gradient pad 23 can be sufficiently bited into the side surfaces 51 and 53 of the suspended loads 50 and 52, a clamping force proportional to the suspended load is generated, and the suspended load slips. It can be safely lifted, transported and suspended without the danger of falling.

  Since the gradient pad 23 is detachable, a plurality of types of gradient pads 23 having tip surfaces with various inclination angles θ are prepared, and the tip of the inclination angle θ substantially matches the gradient of the holding surface of the suspended load. Gradient pad 23 having a surface can be attached to fastening bolt 20 together with guide plate 31 to perform operations such as lifting.

  Means for making the gradient pad 23 detachable with respect to the fitting recess 34 at the tip of the fastening bolt 20 is arbitrary. In the illustrated embodiment, as described above, the circlip 22 formed of an elastic material is accommodated in the large-diameter portion on the back side of the fitting recess 34 in a state where the diameter is expanded, thereby preventing the gradient pad 23 from falling off. At the same time, the guide plate 31 disposed between the gradient pad 23 and the tightening bolt 20 functions as a removal tool, so that the gradient pad 23 can be removed by a simple operation. That is, when the tightening bolt 20 is rotated in the loosening direction, the guide plate 31 hits the pressure nut 13 and when the tightening bolt 20 is further rotated backward in the same direction, the pulling tension is applied to the gradient pad 23. Therefore, the circlip 22 accommodated in the normal state (expanded state) in the large-diameter portion on the back side of the fitting recess 34 is reduced in diameter and accommodated in the annular groove of the shaft portion 28, and the tip side from the step It can pass through the small diameter part. Thus, the gradient pad 23 can be pulled out from the tightening bolt 20 by a simple operation and can be detached.

It is a perspective view which shows one Embodiment of the screw-type clamp by this invention. It is sectional drawing of this screw type clamp. It is a side view of the gradient pad used for this screw type clamp. It is a perspective view of the guide plate used for this screw type clamp. It is AA sectional drawing in FIG. It is a state figure when pinching and lifting a slope of channel steel with this screw type clamp. It is a state figure when pinching and lifting the gradient surface of I-shaped steel with this screw type clamp. It is a front view which shows the example of a conventional structure of a screw type clamp. FIG. 9 is a state diagram when the inclined surface of the channel steel is sandwiched and lifted by the screw-type clamp of FIG. 8. FIG. 9 is a state diagram when the I-shaped steel gradient surface is sandwiched and lifted by the screw-type clamp of FIG. 8.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Screw type clamp 11 Clamp main body 12 Leg part 13 Leg part 14 Opening part 15 Receptacle 16 Coil spring 17 Spherical shape bearing 18 Engagement tooth 20 Tightening bolt 21 Male screw 22 Circlip 23 Gradient pad 24 Engagement tooth 25 Handle 26 Pressure nut 27 Coil spring 28 Shaft portion 29 Annular groove 30 Roughly rectangular portion 31 Guide plate (rotation restricting means)
32 Square opening 33 Guide bar 34 Fitting recess 35 Suspension ring 36 Suspension ring

Claims (3)

A generally U-shaped clamp body having a pair of legs facing each other across the opening, a receiver attached to be able to move relative to one leg, and screwed to the other leg to move forward and backward in the axial direction In a screw-type clamp that has a clamping bolt that can be lifted in a state in which a suspended load inserted into the opening is received and clamped between the clamp and the clamping bolt, the surface is perpendicular to the axis of the clamping bolt. When a gradient pad having a tip surface inclined at a predetermined angle is attached to the tip of the fastening bolt so as to be relatively rotatable with respect to the fastening bolt , and the fastening bolt rotates and moves forward and backward with respect to the opening. A screw-type clamp characterized in that a rotation restricting means for restricting the rotation of the gradient pad and maintaining the tip end face in an inclined state at the predetermined angle is provided between the gradient pad and the clamp body . 2. The screw clamp according to claim 1, wherein the gradient pad is detachably attached to the tip of the tightening bolt . The screw type clamp according to claim 1 or 2 , wherein the rotation restricting means comprises a guide plate having a pair of guide bars sandwiching the clamp main body and being non-rotatable relative to the gradient pad .

Images