US 2033227 A
Abstract available in
Claims available in
Description (OCR text may contain errors)
March 10, 1936.
K, R. BRCBWN ROD DRIVER Filed Aug. ll, 1932 Patented Mar. 10, A 1936 PATENT OFFICE BOD DRIVER Kenneth R. Brown, Rockford, IIL
Application August 11, 1932, Serial No. 628,292
This invention relates to rod drivers and has special reference to a device particularly adapted for the driving of metal rods or tubes such as used for making connection to ground for lightning arresters or towers or for grounding the neutral conductors of secondary electric distribution systems.
'Ihe present invention contemplates the provision of means for conveniently and eiiiciently driving ground rods of the type employed for grounding lightning arresters and in making other electrical ground connections. These rods are customarily from eight to twenty feet long and are of relatively thin cross-section. It has been customary in the past to drive these rods by means of a sledge operating against the end of the rod and, because of their length, it has been necessary to make special provision for driving them. In some instances, it has been necessary to build a scaffolding so that the person driving the rod may be elevated to a sumcient height to drive against its end. In other instances, and wherever possible, they have been driven next to poles so that the person doing the driving might climb the pole and drive against its end. In each instance, however, it has been necessary to provide two workmen, one swinging the sledge against the end of the rod and one to hold the rod. I'his difficulty in driving is beset by a number of serious disadvantages. As previously mentioned, it is often necessary to build a. scaffolding. On the other hand, when the person driving drives from a pole, it is necessary for the linemen to suspend operations on that pole while the driving is going on because of the danger of the men above dropping tools and the danger that the swaying of the pole due to the driving might injure one of the linemen by contact with live wires. In addition to this, the operation has a certain element of danger because of the difficulty of holding a long rod of this character perfectly still. Often the rod sways because of its exibility so that the person driving misses the end of the rod with the sledge. In some instances, the person driving has thus lost his balance and, in others, they have dropped the Sledge striking the person below who is holding the rod. Furthermore, when long rods are used, the rods must be of greater diameter than is necessary for the purpose in order to give them suillcient rigidity to permit their being driven from the end.
An object of the invention is to provide a generally improved tool for driving rods from the ground wherein an impact shoulder is positioned on the rod intermediate its ends and is movable along the rod as driving proceeds and a driving member is disposed above the shoulder for imparting a driving force to the shoulder and thence to the rod.
A further object oi the invention is to provide a driving chuck having novel and highly eiiicient clutch means for securing the chuck to the rod.
I have also aimed to provide a driving member of novel structural characteristics adapted to facilitate the use of the device.
Another object of the invention is to provide a driving device wherein the driving member is balanced about the rod and is of such weight as to provide a driving impact against the shoulder, the member having means for slidably securing the same on the rod and permitting its lateral withdrawal from the rod.
Other objects and attendant advantages will become apparent to those skilled in the art from the following description and accompanying drawing, in which Figure l is a vertical perspective showing the driving device in position upon a rod;
Fig. 2 is a longitudinal section through the driving member and chuck;
Fig. 3 is a lateral section through the chuck taken on the line 3 3 of Fig. 2;
4 is a section taken on the line 4 4 of Fig. 5 is a lateral section taken on the line 5 5 of Fig. 2;
Fig. 6 is a section on the line 6 6 of Fig. 5 showing the spring detent. and
Fig. 7 is a longitudinal section through a modified form of chuck.
My invention contemplates the provision of a chuck or driving shoulder arranged to be adjustably positioned upon the rod at a point adjacent to the ground and convenient for driving. A driving member or hammer is slidably positioned upon the rod above the chuck so that it may be manually raised and forced downward against the chuck to impart a driving force to the rod. The chuck is so arranged that as the driving proceeds it may be raised so that it will always occupy a convenient position for an operator standing upon the ground. This arrangement accomplishes two purposes, rst, it permits the operator to do the driving from the ground without any scaffolding or elevated support whatever, and, secondly, it permits a single person to carry on the entire operation eliminating the necessity of having a second person hold the rod during the driving thereof.
Referring to the drawing, the numeral 9 designates generally a cylindrical chuck having a centrally disposed bore H adapted to receive the ground rod designated generally by the numeral I2. The chuck is provided with two angularly .disposed bores I3 and I4 'arranged to intersect the central bore II, as best shown in Fig. 3, the intersection being such that the junction between the central bore and the bores I3 and I4 serve to retain clutch balls I5 and I6 and prevent their v passage into the central bore. Coil springs Il and I8 are positioned in the bores I3 and I4 and bear against the bottom of the clutch balls I5 and I6. The lower ends of the springs I'I and I8 bear against a pin I9 which extends laterally through the chuck and against the lower ends of the bores I3 and I4. It will be seen that when the rod I2 is inserted in the central bore II, the clutch balls are moved downward somewhat in the bores I3 and I4, the springs maintaining-the balls so that they will bear at one side against the sides of the bores I3 and I4 and at the other side against the rod l2. If force is applied to the upper end of the chuck, the balls will be wedged between the sides of the bores and the rod preventing relative movement in Vthis direction. The rod I2 usually consists of a steel cen-v ter, as shown at 2l, having a copper coating, as shown at 22. During this wedging operation, the balls slightly distort the soft copper coating and give a rm grip of the chuck on the rod. However, the curved surface of the balls is not such as to cut or gouge oil the soft copper coating but merely produce a surface indentation. If
desired, the slope of the diagonal bores I3 and I4 may be such that when the chuck is` used on a rod of such size as to completely illl the central bore, the clutch balls will occupy a clutching position between the ends of the bores, so that when slightly smaller rods are used, such as indicated in dotted lines in Fig. 2, the balls can move to a clutching position at the end of the bores as shown -in dotted lines in the same figure.
The driving member or hammer consists of a central weightportion designated generally by the numeral 23 and a pair of handles 24 and 25 positioned on opposite sides of the central portion 23, the handles being adapted to be grasped by the operator to raise the weight and drive it downwardly against the chuck. i The hammer is provided with'a longitudinal slot 26 extending from the side to the center of the central portion 23 for the purpose of receiving the ground rod I2. It will be seen that through the provision of this slot, the hammer may be moved laterally over the rod. In order to hold the rod at the center of the hammer, a retainer, designated generally by 2l, is positioned in a lateral slot 28 and extends into the center of the hammer completely around the position normally occupied by the ground rod, as best shown in Fig. 5. The lower side of the slot is provided with an arcuate groove 29 having circular depressions 3l and 32 at opposite ends thereof for a purpose presently to be described. The retainer 2l is provided with an inner semi-circular portion 33 having a vcentral opening 34 for the Vreception of the ground rod and flared ends 35, the distance between these ends being at least as much as the distance across the slotl 26. A handle 36 is secured to the semi-circular portion 33 and extends outward lthrough the slot 28 so that it may be grasped by the fingers, the handle serving to rotate the semi-circular portion 33 between a position shown in lFig. 5 wherein the semicircular portion extends across the slot 26 and a position at the other end of the slot in which the opening 35 in the semi-circular retainer portion coincides With the slot 26 so that the hammer may be removed from the rod.
In order to hold the retainer in the hammer when the hammer is oi from the rod, a ball detent is provided, shown in Fig. 6. This consists of a bore 3l on the bottom side of the retainer handle 36 arranged to receive a spring 38 and a ball 39. The bore 3l is in a position such that the ball 39 will rest inthe groove 29 or either ^.of the depressions 3l and 32, the spring 38 maintaining the ball iirmly in these depressions. The circular depressions or sockets 3l and 32 are provided so that the ball 39 will cooperate therewith to secure the retainer in either of the abovementioned positions.
In Fig. 7, I haveshown a modied form of chuck. This consists of a body portion 4I having an axial bore 42 and opposed slots 43 and 44 at its upper end. Clamping ngers 45 and 46 are supported in the slots 43 and 44 on pins 4l and 48, the inner ends of the ngers being arranged to partially surround the rod I2 transversely of its length, as shown at 49. The inner ends of the fingers are also provided with an arcuate face 5I arranged to come into contact with opposite sides of the rod when the outer ends o the fingers are moved downward to grasp the rod. In this form, the lingers 45 and 46 are so 'arranged that the ends will come into contact with the rod before the fingers reach a horizontal position so that impacts of the hammer 23 will be exerted against the fingers intermediate their ends and not against the body portion 4I, so that at each impact the lingers will be caused to grip the rod tightly.
In operation, the chuck is slipped over the bottom of the rod I2 and movedupward thereon a suitable distance for driving. 'Ihe end of the rod is then placed against the ground at the point in which the rod is to be driven and the hammer is ypositioned on the rod. This is accomplished by having the retainer with the ball 39 in the circular depression 3l, whereupon the opening 35 will coincide with the slot 26 so that the hammer-may beV moved laterally onto `the rod. The handle 36 of the retainer is then moved along the slot 28 until the ball 39 drops into thel depression 32, whereupon the hammer will be securely held on the rod. The operator then grasps the handles 24 and 25 to raise the hammer and either allows it to fall or forces it downward against the chuck in a driving stroke. These driving strokes are repeated until the rod.
has moved into the ground a suicient distance to lower the chuck to an inconvenient position. At this point the retainer may be rotatedto the open position so that the hammer may be removed from the rod above the chuck and may be slipped onto the rod Vbelow the chuck to give the chuck a tap at the bottom to loosen the clutch balls I5 and I6 and move the chuck up to a more convenient driving position. The hammer is then again placed on the rod and driving continued. These operations are repeated until the rod is inserted into the ground a suflicient depth, which may be until the top of the rod is almost ilush with the surface of the ground.
Attention is directed to the fact that all of the operations involved in the driving of the rod are carried out from the surface of the ground, thereby relieving the operator of vthe necessity of climbing or the necessity of constructing a scaffolding. 'I'he operations are conveniently carried out by a single operator, thereby eliminating the In combination, a long, slender ground rod of necessity of two workmen. Because of the fact relatively thin cross-section adapted to be driven that the hammer is secured directly on the rod, into the ground substantially its entire length for there is no danger of injury to the workmen. grounding connections and the like, a chuck body 5 This simple and convenient method of driving having a central bore to freely receive the rod, a
5 the rods permits their installation in much more driving shoulder at each end of said body, and desirable locations than at present because it is rod gripping means within said chuck body havnow more convenient to locate them near a pole ing wedging engagement between the rod and because of the ease in driving. Furthermore, it body when force is applied by striking downwill be seen that rods of any length can be driven wardly on the upper driving shoulder and releas- 10 with equal facility so that when the present deing from said wedging engagement when force vice is employed there is no reason for reducing is applied by striking upwardly on the lower drivthe length of the rod below that normally deing shoulder, said wedging engagement serving sirable because of the difficulty of driving the to xedly attach said chuck body to the rod so longer rod. Because of the fact that the driving that successive driving blows against the upper 15 operation is carried on relatively close to the shoulder will force the rod into the ground and surface of the ground, the diameter of the rod release of said engagement will permit quick slidmay be materiali:Y less than has heretofore been ing of the chuck body to a higher driving position necessary with long rods, the increased diameter on the rod, and a driving hammer having a weight previously being required to permit the driving body with handles projecting from opposite sides 20 -for end and the hammer used at the lower end the center thereof when placing the hammer body 25 by means of tHe present device is about 40% the rod above and below the chuck body and 30 below the cost of previous methods. permitting quick removal therefrom, whereby the The hammer retainer is arranged to be secured hammer may be quickly positioned for free main either an open or a. closed position in order nipulation up and down on the rod above the to prevent the retainer from falling out when chuck body to impart rod driving strokes against it occupies its open position and to prevent the the upper driving shoulder and below the chuck 35 retainer from shifting during the driving operabody to impart chuck releasing strokes against tions. the lower driving shoulder, and whereby upon While I have thus described and illustrated a successively advancing the chuck body to higher specific embodiment of my invention,vI am aware working positions on the rod the long, small di- 40 that numerous alterations and changes may be ameter rod may be driven into the ground to made therein without materially departing from considerable depth without whipping or distorthe spirit of the invention or the scope of the ing the rod. appended claim, in which I claim: KENNETH R. BROWN.