US 2896896 A
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M. R. REVZIN ACCESSORY CLAMP July 28, 1959 Filed Jan. 28, 1955 2 Sheets-Sheet 1 INVENTOR ATTO EY July 28, 1959 M. R. REVZIN ACCESSORY CLAMP 2 Sheets-Sheet 2 Filed Jalfl. 28, 1955 ACCESSORY CLAMP Milton R. Revzin, Youngstown, Ohio Application January 28, 1955, Serial No. 484,807
1 Claim. (Cl. 248229) The present invention relates to clamps and the like, and more particularlyto a portable clamp assembly for attaching lamps and other accessories to fixed objects, such as Workbenches, tables, etc.
As an overall object, the present invention seeks to provide a novel and improved portable clamp assembly which is economical to manufacture, light in weight, and operative in an improved and efiicient manner to attach such accessories as reading or flood lamps, photographic equipment and the like to fixed or stable objects of irregular size and shape, such as tables, chairs, workbenches, desks, and similar articles generally found about the home, office or workshop.
More particularly, it is an object of the invention to provide an improved C-type clamp having primary and secondary pressure applying means thereon whereby great clamping pressures may be applied with little effort upon the part of the operator. In this respect the invention comtemplates the provision of a C-type clamp having an ordinary screw type primary clamping member which may be brought into pressure engagement with an object to which the clamp is to be aflixed, and
having a novel and improved secondary pressure apply-' ing means comprising combined screw and lever means. Thus, after initial clamping engagement has been obtained by means of the primary clamping member, the combined screw and lever secondary clamping means is manipulated to apply a great clamping pressure so that the clamp and any accessories supported thereby are firmly and stably mounted.
While I am fully aware that clamps of this general type are old and well known in the art, the invention in the present instance resides in the provision of a clamp having specific novel features of construction which improve the operation of the clamp and permit of its being made of light weight cross sections and of light weight materials, such as aluminum, for example. Thus, it will be understood that clamps of this general type, being capable of exerting great clamping forces, must have great strength in the highly stressed sections thereof. In the past, therefore, such clamps have been constructed of heavy materials, having heavy cross sections at critical areas. Otherwise such clamps have been ineifective for the purpose intended.
Yet another object of the invention is the provision of a novel and improved high strength clamp capable of exerting great clamping pressures, which combines characteristics of stability, light weight and high strength with characteristics of neatness and compactness, rendering the clamp ideally suited for general purpose home and shop use for the quick attachment of lamps and other accessories.
A further object of the invention resides in the provision of a novel C-type accessory clamping attachment 2,896,896 Patented July 28, 19 59 2 having the features above described which incorporates novel and improved means for attaching accessory apparatus thereto.
The above and other objects of the invention will be come apparent upon full consideration of the following detailed specification and accompanying drawing wherein is disclosed a certain preferred embodiment of the invention.
In the drawing:
Figure 1 is a perspective view of my improved clamp, illustrating the manner in which the same is employed for the attachment of lamps and other accessories;
Figure 2 is an enlarged perspective view of the clamp of my invention;
Figure 3 is a side elevation, partly in section, of the clamp of Figure 2; and
Figure 4 is a section view taken generally along lines IVIV of Figure 3.
Referring now to the drawing, and initially to Figure 3 thereof, the numerals 10 and 11 designate the principal parts or components of my novel C-clamp. The first mentioned member 10 comprises an inverted L-shaped member, which may be formed of die cast aluminum, for example. The upper or horizontal leg portion 12 of the clamp member 18 is provided at its outer end portion with a downwardly facing clamping pad or surface 13; and in accordance with the teachings of the invention the vertical leg portion 14 of the member 10 is of a hollow U-shaped cross section, as indicated in Figure 4.
The second mentioned of the principal clamping parts 10 and 11 comprises an L-shaped member which is generally of T-shaped cross section throughout, as indicated in Figure 4, and which is provided at the outer end of its horizontal leg 15 with a bulbous portion 16 having a vertical threaded bore therethrough. Received within the bore is an elongated clamping screw 17, having a knurled operator 18 at its outer end and a swiveled clamping pad 19 at its upper end. The arrangement is such that the screw 17 may be adjusted to move the swiveled pad 19 toward the upper clamping pad 13 whereby to come into clamping engagement with an article positioned between the-two pads. This, of course, is the usual manner of operating a conventional C-clamp.
As shown in Figure 3, the lower clamping part 11 is connected to the upper clamping part 10 by means of a pivot pin 20 which engages the upper end portion of the member 11 and the upper corner portion of the inverted such width as to closely fit between the opposed side walls of the U-shaped portion 14.
At the lower end of the vertical portion 14 there is provided a boss 22 having a threaded bore therein for the reception of an adjusting screw 23, the latter being provided with a knurled control knob 24 for easy manual manipulation. The adjusting screw 23 is arranged to engage the outer surface of the flange 21 so that upon inward movement of the screw, for example, the lower clamping member 11 is urged away from or out of the channel defined by the U-shaped lower portion 14 of the upper clamping member 10. Of course, since the parts 10 and 11 are pivotally interconnected at the upper corner of the C, the horizontally extending leg portions 12 and 15 of the clamping parts are caused to move together to exert a further clamping pressure upon an article previously clamped between the pads 13 and 19 through appropriate adjustment of screw 17.
It will be observed that the lever arm from the pivot pin 20 to the secondary adjusting screw 23 is considerably longer than the lever arm from the pin 20 to the clamping pad 13, so that there is substantial multiplication of clamping forces. Moreover, it is contemplated that the screw '23 will be of a finer pitch than the primary adjusting screw 17, so that an extremely high clamping force may be obtained 'upon manipulation of the secondary screw 23. Thus, it will be understood that the primary adjusting screw 17 may have a relatively coarse pitch, permitting rapid movement of the pads 13 and 19 into clamping engagement. After a preliminary clamping engagement has been thus obtained the secondary fine pitch screw 23 is manipulated to effect the desired firm clamping pressure.
In accordance with the preferred teachings of the invention, the exposed flange 25 is of such width as to extend from one outer surface to the other of the spaced side walls of the U-shaped section 14. Thus, as clearly shown in Figures 2 and 4, when the principal clamping parts 10 and 11 are in their normal nested arrangement the inner or exposed flange substantially covers the open side of the U-shaped section, providing a neater appearing assembly, as well as preventing the entry of dirt and other foreign particles into the channel 14 to interfere with the proper smooth operation of the clamping parts.
Although my novel clamp may have other various uses and applications, it is primarily intended to be employed for the mounting of lamps, photographic equipment and the like. Thus, in accordance with the teachings of the invention there is provided along one side of the upper clamping part 10, adjacent the upper portion thereof, an attachment clamping ring 26 which is preferably formed as an integral cast part of the upper clamping part 10. The clamping ring 26 defines a vertically disposed tubular opening 26' which is adapted to closely receive an elongated tubular accessory part 27 which in the illustrated apparatus forms a standard or support for a lamp 28.
As shown in Figure 2, the clamping ring 26 is provided along one side with an enlarged boss 29 which is split radially of the tubular opening and which includes a threaded bore 30 adapted to receive a tightening screw 31.. The arrangement is such that when the tubular accessory support 27 is slidably inserted in the clamping ring 26 the tightening screw 31 may be manipulated to firmly grip the support 27 in any pre-adjusted vertical position, substantially in the manner shown in Figure 1.
It should be particularly noted that the innermost side wall portion of the tubular opening 26' is tangent with the vertical side wall portion of the clamping part It). This is an important feature of the invention in that when the tubular support 27 is secured within the clamping ring 26 the adjacent side wall portions of the support 27 and upper clamping part 10 are in contact, so that the clamp serves as a steadying means for the support 27. In this manner, the assembly is rendered more stable, and thus more suitable for photographic work, for example; and, in addition, the clamping ring 26 is less subject to damage from accidental blows imparted to the elongated support 27.
It should thus be understood that I have carried out the several objects of the invention. My improved 0- type clamping device, while not new in its broad aspects, incorporates several important features of novelty which render the clamp substantially more suitable for general use, and which provide a neater appearing, light weight and economical device which is ideally suited for general use about the home, oflice or workshop for supporting lamps, and other equipment.
that each of the parts may have a strong and substantial cross section to resist twisting and bending of the parts during the application of high clamping pressures, while at the same time the assembly is maintained neat and compact. Moreover, such construction permits of the use of such light weight materials as aluminum, without material loss of strength.
As shown in Figure 2, the outer part has a U-shaped cross section with relatively long leg or side wall portions 1 so that a high strength cross section is aflorded; and
the inner part is of I, or preferably T cross section, arranged to nest compactly within the U section of the other part. The T section is preferred in that the outer flange portion serves to completely cover the exposed outer leg portions of the U section to render the overall assembly neater in appearance, as well as to prevent the entry of foreign matter in the working assembly.
Another important feature of the invention resides in the coaction between the outer clamping part, of U-shaped cross section, and the clamping ring 26 formed integrally therewith. The arrangement is such that the tubular opening defined by the clamping ring is tangent with the flat outer surface of the U-sectional clamping part so that such surface is operative to brace a tubular accessory support gripped within the clamping ring.
It will be readily apparent that my improved clamping device, although embodying a number of novel and advantageous features, is essentially simple in structure, and is adaptable to mass production manufacture by means of conventional die casting and machining operations.
It should be understood, however, that the embodiment herein specifically illustrated and described is intended to be representative only, as many changes may be made therein without departing from the clear teachings of the invention. Reference should therefore be had to the following appended claim in determining the full scope of the invention.
In a C-type accessory clamp of the type having primary and secondary clamp adjusting means the improvement comprising a first inverted L-shaped clamping part having a horizontally extending leg portion and a downwardly extending leg portion, said downwardly extending leg portion being of greater length than said horizontally extending leg portion and having an inwardly opening U-shaped cross section throughout its length, a second L-shaped clamping part having a horizontally extending leg portion and an upwardly extending leg portion, said upwardly extending leg portion being of longer length than said horizontally extending leg portion of said second L-shaped member and having a generally T- shaped cross section throughout its length, said upwardly and downwardly extending leg portions being adapted to fit in nesting relation with the exposed flange of said T-shaped cross section overlying the end portions of said U-shaped cross section, a pivot pin pivotally interconnecting said L-shaped clamping parts, said pivot pin being adjacent the corner of said first mentioned clamping part and pivotally supporting the end of said upwardly extending portion of said second mentioned L-shaped clamping part, said downwardly extending leg portion of said first mentioned clamping part having a boss thereon adjacent the lower end thereof, an adjusting screw received in said boss and extending through said downwardly extending leg portion and into engagement with said upwardly extending leg portion whereby upon manipulation of said adjusting screwsaid clamping partsare caused to pivot in a clamping direction, said horizontal leg portion of one of said L-shaped clamping parts having an inwardly facing clamping pad thereon, said horizontal leg portion of the other of said L-shaped clamping parts hqvhm mi artimmhlp. nnrimine nlamrai'nti nad thereon. the
clamping pad carried by said horizontally extending leg portion of said first mentioned clamping part whereby there is substantial multiplication of the clamping forces exerted upon tightening of said adjusting screw, a clamping ring carried integrally with said first mentioned clamping part along a side wall of said downwardly extending portion, said clamping ring defining a tubular opening adjacent the outer surface of said side wall having its longitudinal axis parallel with said side Wall.
References Cited in the file of this patent UNITED STATES PATENTS