US3632152A

US3632152A - Hinged clamp

Info

Publication number: US3632152A
Application number: US31508A
Authority: US
Inventors: Charles J Renfroe
Original assignee: J C Renfroe and Sons Inc
Current assignee: J C Renfroe and Sons Inc
Priority date: 1970-04-24
Filing date: 1970-04-24
Publication date: 1972-01-04
Anticipated expiration: 1989-01-04
Also published as: FR2086326A1; DE2119951C3; NL156990B; JPS581281B1; BE766177A; FR2086326B1; NL7105594A; DE2119951A1; DE2119951B2; GB1294431A

Abstract

A hinged clamp for engaging the flange of a beam comprising first and second complementary clamping members, each of which has a spaced pair of hooks in mutually opposed relationship when the clamping members are in a clamped position. One of the clamping members is rigidly attached to a hoist plate which has a load supporting means thereon. The second clamping member is movable between a clamping position in complementary alignment with the other clamping member engaging the inner sides of the flange of a beam, and an open position disengaged from the flange. To lock the clamp against movement relative to the beam, a wedge is driven between the beam and the clamp at a point between the spaced pair of hooked clamps.

Description

United States Patent inventor Charles J. Reniroe Jacksonville, Fla. Appl. No. 31,508 Filed Apr. 24, 1970 Patented Jan. 4, 1972 Assignee J. C. Reniroe 8: Sons, Inc.

Jacksonville, Fla.

HINGED CLAMP 10 Claims, 3 Drawing Figs.

US. Cl 294/85, 294/82, 248/228 Int. Cl. B660: 1/34 Field 01 Search 294/67, 82, 85, 87.22, 87.26; 248/227, 228

References Cited UNITED STATES PATENTS 2,765,139 10/195 White.. 24 8/228 2,916,244 12/1959 Renfroe 248/228 Primary Examiner-Joseph Wegbreit Assistant Examiner-Johnny D. Cherry Att0rneyBitch, Swindler, McKie & Beckett ABSTRACT: A hinged clamp for engaging the flange of a beam comprising first and second complementary clamping members, each of which has a spaced pair of hooks in mutually opposed relationship when the clamping members are in a clamped position. One of the clamping members is rigidly attached to a hoist plate which has a load supporting means thereon. The second clamping member is movable between a clamping position in complementary alignment with the other clamping member engaging the inner sides of the flange of a beam, and an open position disengaged from the flange. To lock the clamp against movement relative to the beam, a wedge is driven between the beam and the clamp at a point between the spaced pair of hooked clamps.

mmcnm 4:912 v 316321152 INVENTOR CHARLES J. RENFRGE ATTORNEYS nINean CLAMP BACKGROUND OF THE INVENTION 1. Field of the Invention This invention relates generally to beam clamps and similar constructions, and more particularly to a hinged clamp which can be anchored to the flange of a beam such as an I beam, and retained in a fixed position thereon.

2. Description of the Prior Art The prior art provides a multiplicity of clamps which attach to the flange of a structural beam as a means for lifting the beam, or as a means for suspending loads from the beam. Many prior art clamps have been designed with an interrela' tionship between the holding abilities of the clamp and the placing of a load upon the clamp. Such clamps are locked in position only when a force is applied to their load attaching means. The disadvantage of such systems is the fact that the clamp can become unlocked if the load is momentarily relaxed. Also, beam clamps of this type can be attached or removed from a beam only when disconnected from the usual hoist hook, which often poses an inconvenience. Other prior art clamps lock irrespective of the load placed upon them, but do so by means of mechanisms which are cumbersome to use, or for which special tools must be provided. Most of the clamps present in the prior an add a multiplicity of parts and rather complicated adjusting or attaching mechanisms in order to achieve the high standards of safety and reliability necessary in such equipment. This increases the time and skill necessary to install or remove the clamp, and adds to the chances of improper installation.

SUMMARY OF THE PREFERRED EMBODIMENTS The beam clamp set forth herein is designed to overcome the above-mentioned disadvantages and problems. The invention provides a lightweight, compact, reliable, versatile, and safe beam clamp which has a minimum of parts. This clamp can be used for hoisting a beam or as a means by which loads can be suspended from a beam. It engages the flanges of beams such as an I beam in a simple manner and once installed is positively locked against opening or relative movement on the beam. It does not rely on applied load for locking and can be installed while attached to a lifting hook. It reduces to a minimum the chances of improper installation. It has a low profile, making it adaptable for use in confined spaces. Basically, the hinged clamp advanced in the instant invention consists of a pair of complementary clamping members. The first clamping member is rigidly attached to a hoist plate which ineludes a load attaching means such as a shackle thereon. The second clamping member is connected to the hoist plate by means of a hinge mechanism. Each of the clamping members includes hook means extending laterally outwardly in opposite directions from said hoist plate and then downwardly and inwardly and terminating in free ends. The hinge mechanism permits the second clamping member to be rotated outwardly about a pivot, as well as to be moved laterally outward, so that the second clamping member is movable between a clamping position in complementary alignment with the first or fixed clamping member with the free ends of said hook means spaced apart in mutually opposed relationship for engaging the underside of the flange of a beam, and an open position in which the hook means of said movable clamping member is clear of the flange of the beam, facilitating mounting and demounting. The hinged flange clamp is locked by a locking means in the clamping position against lateral movement outward, as well as against relative movement with regard to the beam. The load carried by the movable clamping member is imparted to the hoist plate through the hinge mechanism upon which it is mounted and, in particular, through the element upon which the movable clamping member pivots when it is in the clamping position. The hook means on the second clamping member terminates in a load bearing surface, which is so aligned with respect to the pivot point that no rotational force is imparted to the hook means when the load bearing surface engages the beam by the application of a vertical force to said load supporting means.

An object of this invention is to provide a new and improved flange clamp that is versatile, reliable, simple in construction, and which provides a maximum of safety in use.

Another object of this invention is to provide a new and improved flange clamp that is positively locked against relative movement with regard to the beam to which it is attached.

Another object of this invention is to provide a new and improved flange clamp which can be readily mounted or demounted from a beam.

Another object of this invention is to provide a new and improved flange elamp in which one of the hooks moves laterally and rotationally to facilitate mounting and demounting of the clamp.

Another object of this invention is to provide a new and novel flange clamp with several load supporting means.

DESCRIPTION OF THE DRAWINGS FIG. 1 is a side elevation of a clamp constructed in accordance with the instant invention.

FIG. 2 is a top plan view of the apparatus shown in FIG. 1.

FIG. 3 is an end elevation of the apparatus shown in FIG. 1.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring now to the FIGURES, the hinged clamp of the present invention consists of an upright hoist plate 10 having a load supporting means such as a shackle 11 therein, a fixed clamping member indicated generally at 12, a movable clamp ing member indicated generally at 13, and a cam means such as a wedge 14. This hinged flange clamp is designed for use with beams such as an I beam, a portion of which is shown in the drawings. Such a beam has a web 15, and a flange 16 with inner surfaces 17 and an outer surface 18.

Fixed clamping member 12 comprises a pair of aligned parallel hooks 20 which are spaced apart longitudinally of and fixedly attached to hoist plate 10. I-Iooks 20 have load-supporting surfaces near their ends which engage inner surfaces 17 of flange l6.

Movable clamping member 13 comprises a pair of aligned parallel hooks 25 which are spaced apart longitudinally of hoist plate 10 with a spacer rod 26 fixed therebetween. The pair of hooks 20 and the pair of hooks 25 have base portions adjacent the hoist plate 10 and extend laterally outwardly in opposite directions from the hoist plate 10 and then downwardly and inwardly and terminate in free ends. Clamping member 13 is mounted in such a manner that it can be moved rotatably and laterally to facilitate mounting and demounting of the clamp. Clamping member 13 is mounted on and pivots about a hinge pin 27 which extends longitudinally of the hoist plate 10 outwardly from the outside of the base portion of each of the hooks 25. Attached to the side of hoist plate 10 are a pair of spaced parallel hinge plates 29 located longitudinally outside of the hooks 25. Each hinge plate 29 has a slot 30 extending laterally of the hoist plate 10 and terminating in a downwardly turned portion or detent 31 at the inner end thereof. Slots 30 receive hinge pin 27 and by such arrangement clamping member 13 can be moved laterally and rotatively in slot 30 between a laterally inward clamping position in which hooks 25 are aligned with hooks 20 with the free ends of such hooks spaced apart in mutually opposed relationship for engaging the beam flange, and a laterally outward open position in which hooks 25 are free to pivot outwardly around the pin 27 so that their free ends clear the beam flange 16. Specifically, the slot 30 should extend laterally outwardly a sufficient distance so that the distance between the outer end of the slot and the lower outer edge of the beam flange is less than the distance between the pin 27 and the nearest point 33 on the inner end of the hooks 25. Detents 31 engage hinge pin 27 when clamping member 13 is in the clamping position, to preclude lateral movement of pin 27 when beam flange 16 is engaged. Plates 32 cover slots 30 to prevent fouling thereof.

To provide structural integrity, a spacer element in the form of an auxiliary hoist plate or shackle 21 can be fixedly attached between hooks 20. Shackle 21 provides the structural support necessary while adding to the versatility to the instant invention by providing a second load supporting means. The alternate shackle 21 is mounted horizontally, normal to the shackle and in horizontal alignment with the free ends of the hooks and 25. Thus, a horizontal pulling force applied to the shackle 21 does not tend to rotate the clamp about the ends of the hooks 25.

The load exerted on movable clamping member 13 by beam flange 16 when engaged by member 13 is transmitted to hoist plate 10 by means of pin 27, upon which movable clamping member 13 is mounted.

Hooks are provided with load-supporting surfaces 33, which engage the underside 17 of flange 16. The load carried by clamping member 13 will be applied to the flange clamp through the pivot point, which is hinge pin 27. In order to prevent the development of a moment arm about hinge pin 27, resulting in the application of rotational forces to hooks 25 when a vertical force is applied to the shackle 1 1, load-bearing surfaces 33 are so positioned as to act along vertical force line 35, engaging flange 16 at a point directly beneath hinge pin 27. The load-bearing surfaces 33 are defined by the tops of shoulders protruding upwardly from near the inner free ends of the hooks 25. These shoulders provide the highest points on the portions of the hooks 25 which underlie the flange 16 when the clamping member 13 is in its clamping position. In such clamping position the shoulder tops, that is the loadbearing surfaces 33, are vertically aligned with the hinge pin 27.

Although not shown, the positions of the elements of the pin and slot connection can be reversed, that is, the pin can be attached to hinge plates 29 and stationary, while the slots are made part of movable hooks 25. In this case, the load placed upon hooks 25 is still carried by the pin, and load-bearing surfaces 33 are positioned such that they are directly beneath the pin when engaging the beam. Thereby, no rotational force is imparted to hooks 25.

The hinged flange clamp is locked into engagement with the beam, and secured against relative movement therebetween, by lock means such as a wedge 14, which is driven into position as shown in the drawings after clamping members 12 and 13 have engaged flange 16. Upper surface 36 of wedge 14 engages hoist plate 10, while lower surface 37 engages the outer surface 18 of flange 16, forcing hoist plate 10 and beam 16 apart, and locking hinge pin 27 in detents 31. The action of wedge 14 also prevents relative motion between hoist plate 10 and beam 16. Wedge 14 can have

concave surfaces

36 and 27 to provide longitudinal cutting edges which enhance its gripping action against the clamp and the flange, as described in U.S. Pat. No. 2,916,244, issued Dec. 8, 1959, to Charles .I. Renfroe.

Although shown in the Figures as driven in from the side of the movable clamping member 13, wedge 14 can also be inserted from the opposite side. As can be noted from FIGS. 2 and 3, wedge 14 is advantageously installed between the pair of spaced hooks, and hoist plate 10 can be provided with a wedge-receiving seat 39.

The invention is made more versatile by the addition of auxiliary load supporting means in the form of a shackle 21, which can serve as a means of attachment for a guideline used when positioning beam 16, or which can function as a primary load support. When using shackle 21 as a vertical load supporting means, it is advantageous to install wedge 14 from the side of fixed clamping member 12, to eliminate any chance of wedge 14 disengaging.

In operation, movable clamping member 13 is first placed in the open position shown in phantom in FIG. 1. Fixed clamping member 12 is placed into engagement with flange 16. Movable clamping member 13 is then rotated and moved laterally on hinge pin 27 until flange 16 is engaged and hinge pin 27 is seated in detents 31. At this point wedge 14 can be driven in from either side until it is firmly seated against both hoist plate 10 and beam surface 18, thus locking the entire mechanism against movement. To remove the hinged flange clamp, wedge 14 is driven out of engagement, freeing movable clamp member 13 for movement to the open position.

The instant invention offers many advantages, including simplicity of construction and ease of operation. It need not be disengaged from the hoisting hook in order to be installed or removed and does not depend upon loading to positively lock. By virtue of the unique rotational and lateral movement of clamping member 13, the hinged flange clamp has a low profile, while still being extremely simple to engage or disengage from beam 16. This feature is enhanced by the particular placement of load-bearing surfaces 33 directly beneath hinge pin 27, to preclude the application of rotational forces to hooks 25 during lifting. The clamp can be used on the upper flange of the beam to lift beam 16, as shown, or it can be installed on the lower flange of the beam in order that loads such as a chain hoist or similar equipment can be suspended therefrom. Additional versatility is added by auxiliary shackle 21.

The above description and drawings disclose but one of the embodiments of the invention, and it should be understood that the invention is not to be limited thereby, and that various alterations and modifications may be made within the scope of the appended claims.

I claim:

1. A hinged clamp for engaging the flange of a beam comprising fixed and movable complementary clamping members,

a hoist plate rigidly attached to said fixed clamping member and having a load supporting means,

mounting means hingedly attaching said movable clamping member to said hoist plate, each of said clamping members including hook means extending laterally outwardly in opposite directions from said hoist plate and then downwardly and inwardly and terminating in free ends, said mounting means comprising a pin and slot connection attaching said movable clamping member to said hoist plate and bearing the load exerted on said movable clamping member, said movable clamping member being pivotable about said pin and laterally movable along said slot between a laterally inward clamping position in which said movable clamping member is in complementary alignment with said fixed clamping member with said free ends of said hook means spaced apart in mutually opposed relationship for engaging said flange and a laterally outward open position in which said movable clamping member is free to pivot outwardly around said pin to permit its hook means to clear the beam flange, and

locking means to lock said clamp on the beam with said movable clamping member in said clamping position.

2. The clamp of claim 1 wherein said slot means includes a detent at one end thereof for receiving said pin to prevent lateral movement of said pin in said slot when said movable clamping member is locked in said clamping position.

3. The clamp of claim 2 wherein said movable clamping member hook means includes an upwardly protruding loadbearing surface for engaging the under surface of said flange, said load-bearing surface being so aligned with respect to said pin that no rotational force is imparted to said movable clamping member when engaging said flange in said'clamping position by the application of a vertical force to said load supporting means.

4. The clamp of claim 3 wherein said load bearing surface is vertically aligned with said pin when said movable clamping member is in said clamping position.

5. The clamp of claim 1 wherein said locking means comprises a wedge positionable between said hoist plate and the beam flange.

6. The clamp of claim 1 wherein said fixed clamping member has attached thereto an alternate hoist plate having a load supporting means and extending substantially normal to the first named hoist plate.

7. A hinged flange clamp for engaging a beam comprising a hoist plate having a load supporting means, a fixed clamping member rigidly attached to said hoist plate,

a movable clamping member, each of said clamping members including hook means extending laterally outsaid movable clamping member having a pivot pin extending longitudinally of said hoist plate outwardly from the outside of the base portion of each of the hooks of said movable clamping member,

wardly in opposite directions from said hoist plate and 5 said hoist plate having a pair of spaced parallel hinge plates then downwardly and inwardly and terminating in free located longitudinally outside of the hooks of said movaencls, ble clamping member, said hinge plates having slots said movable clamping member being hingedly attached to receiving the pin on each side of the movable clamping said hoist plate for rotational movement about a pivot member and extending laterally of said hoist plate to perbetween a clamping position in complementary align t l0 mit said movable clamping member to be pivoted about with said fixed clamping member with aid free ends of said pin and laterally movable along said slot between a said hook means spaced apart in mutually opposed relalaterally inward clamping position in which said movable tionship for engaging the inner surface of the flange of a p g m r is in c mp ementary alignment with beam, and an open position in which the hook means of said fixed clamping member with said free ends of a said movable clamping member is clear of said beam to Pairs of hooks spaced p in mutually pp relation" allow said clamp to be mounted and demounted, said p for engaging the flange with said P bearing load hook means of said movable clamping member including exerted on said movable clamping member and a laterally an upwardly protruding load bearing surface for engaging outwa'd p Position in which said movable clamping said inner surface of said flange, said load bearing surface member is free F outwardly mound the P to P being so aligned with respect to said pivot that no rotaits hooks to deal: l beam flange, f tional force is imparted to said movable clamping lockfng "F compnsmg a wedge Posltlonable between member when engaging said flange in said clamping posi- Said hols plale and the beam flange lock Said i p tion by the application of a vertical force to said load supthe i l the movable clampmg member Sald porting means, and locking means to lock said clamp in clampmg P I said clamping position 9. The clamp of claim 8 wherein each of said hooks of said 8. A hinged flange clamp for engaging a beam flange commov'flble clampmg membel: have an p y protruding load prising bearing surface for engaging the undersurface of the beam an upright hoist plan; having a load supporting means flange said load bearmg surfaces being vertically aligned with a fi d clamping member and a movable clamping member said pm when said movable clamping member IS in said clamprespectively affixed to opposite sides of said hoist plate, P each of said clamping members including a pair of aligned l The clamp of 9 fmher comprfsmg an ahemflte parallel hooks spaced apart longitudinally of said hoist holst Plate fi between hooks Sald fixed clamping plate with said pairs of hooks having base portions member, said alternate hoist plate having a load supporting jacem Said hoist plate and extending laterally outwardly means and extending substantially normal to the first named in opposite directions from said hoist plate and then holst Plate' downwardly and inwardly and terminating in free ends,

Claims

1. A hinged clamp for engaging the flange of a beam comprising fixed and movable complementary clamping members, a hoist plate rigidly attached to said fixed clamping member and having a load supporting means, mounting means hingedly attaching said movable clamping member to said hoist plate, each of said clamping members including hook means extending laterally outwardly in opposite directions from said hoist plate and then downwardly and inwardly and terminating in free ends, said mounting means comprising a pin and slot connection attaching said movable clamping member to said hoist plate and bearing the load exerted on said movable clamping member, said movable clamping member being pivotable about said pin and laterally movable along said slot between a laterally inward clamping position in which said movable clamping member is in complementary alignment with said fixed clamping member with said free ends of said hook means spaced apart in mutually opposed relationship for engaging said flange and a laterally outward open position in which said movable clamping member is free to pivot outwardly around said pin to permit its hook means to clear the beam flange, and locking means to lock said clamp on the beam with said movable clamping member in said clamping position.

3. The clamp of claim 2 wherein said movable clamping member hook means includes an upwardly protruding load-bearing surface for engaging the under surface of said flange, said load-bearing surface being so aligned with respect to said pin that no rotational force is imparted to said movable clamping member when engaging said flange in said clamping position by the application of a vertical force to said load supporting means.

7. A hinged flange clamp for engaging a beam comprising a hoist plate having a load supporting means, a fixed clamping member rigidly attached to said hoist plate, a movable clamping member, each of said clamping members including hook means extending laterally outwardly in opposite directions from said hoist plate and then downwardly and inwardly and terminating in free ends, said movable clamping member being hingedly attached to said hoist plate for rotational movement about a pivot between a clamping position in complementary alignment with said fixed clamping member with said free ends of said hook means spaced apart in mutually opposed relationship for engaging the inner surface of the flange of a beam, and an open position in which the hook means of said movable clamping member is clear of said beam to allow said clamp to be mounted and demounted, said hook means of said movable clamping member including an upwardly protruding load bearing surface for engaging said inner surface of said flange, said load bearing surface being so aligned with respect to said pivot that no rotational force is imparted to said movable clamping member when engaging said flange in said clamping position by the application of a vertical force to said load supporting means, and locking means to lock said clamp in said clamping position.

8. A hinged flange clamp for engaging a beam flange comprising an upright hoist plate having a load supporting means, a fixed clamping member and a movable clamping member respectively affixed to opposite sides of said hoist plate, each of said clamping members including a pair of aligned parallel hooks spaced apart longitudinally of said hoist plate with said pairs of hooks having base portions adjacent said hoist plate and extending laterally outwardly in opposite directions from said hoist plate and then downwardly and inwardly and terminating in free ends, said movable clamping member having a pivot pin extending longitudinally of said hoist plate outwardly from the outside of the base portion of each of the hooks of said movable clamping member, said hoist plate having a pair of spaced parallel hinge plates located longitudinally outside of the hooks of said movable clamping member, said hinge plates having slots receiving the pin on each side of the movable clamping member and extending laterally of said hoist plate to permit said movable clamping member to be pivoted about said pin and laterally movable along said slot between a laterally inward clamping position in which said movable clamping member is in complementary alignment with said fixed clamping memBer with said free ends of said pairs of hooks spaced apart in mutually opposed relationship for engaging the flange with said pin bearing the load exerted on said movable clamping member and a laterally outward open position in which said movable clamping member is free to pivot outwardly around the pin to permit its hooks to clear the beam flange, and locking means comprising a wedge positionable between said hoist plate and the beam flange to lock said clamp on the beam with the movable clamping member in said clamping position.

9. The clamp of claim 8 wherein each of said hooks of said movable clamping member have an upwardly protruding load bearing surface for engaging the undersurface of the beam flange, said load bearing surfaces being vertically aligned with said pin when said movable clamping member is in said clamping position.

10. The clamp of claim 9 further comprising an alternate hoist plate fixed between the hooks of said fixed clamping member, said alternate hoist plate having a load supporting means and extending substantially normal to the first named hoist plate.