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Publication numberUS2487530 A
Publication typeGrant
Publication dateNov 8, 1949
Filing dateAug 28, 1946
Priority dateAug 28, 1946
Publication numberUS 2487530 A, US 2487530A, US-A-2487530, US2487530 A, US2487530A
InventorsDirksen Ole A
Original AssigneeDirksen Ole A
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Post driver
US 2487530 A
Abstract  available in
Previous page
Next page
Claims  available in
Description  (OCR text may contain errors)

2 Sheets-Sheet l Ole A, Dkselv.


O. A. DHRKSEN New, '3, E949 POST DRIVER Filed Aug. 28, 1946 NM 8 E949 o. A. DHRKSEN 23187530 POST DRIVER Filed' Aug. 28,1946 2 Sheets-Sheet 2 g2 31 mau l 7 02\ 95100 9 i k67 Rs 94 I I 101 96 y N 56 i 7@ '-5 l0 56 "0. v ul I J 47 g v f v gli 46 1061' 31a/umm Ole A. Dirkselb.

Patented Nov. 8, 1949 UNITED STATES PATENT OFFICE 2,487,530 POST DRIVER Ole A. Dirksen, Spencer, Iowa Application August 28, 1946, Serial No. 693,406

4 Claims.

l My inventionrelates to post drivers and more particularly to improvements in fence post drivers.

An object of my invention is to provide novel control means for the hammer of the post driver, whereby there is accurate regulation of thelength of the stroke or drop of the hammer.

Another object is to provide novel means, whereby one lever controls operation of both the brake and lift mechanism of the hammer.

For example, heretofore with the old style drivers there is no way of regulating the length of stroke of drop of the hammer, and also the old style drivers require the use of both hands to operate the brake and lift mechanisms, which requires considerable skill and much practice. Accordingly, ,another object is to provide improvements in fence post drivers, wherein unskilled labor may use a post driver of the present novel type with efficiency equal to a skilled laborer using the old style post driver.

With these and other objects in view, the invention consists in the construction, arrangement and combination of parts hereinafter described and particularly pointed out in the claims, it being understood that I do not intend to limit myself to the details of construction.

In the drawings, like parts throughout the several views are given like numerals and are thus identified in the following detailed description of one embodiment of my invention.

Figure 1 is a perspective view of my novel post driver.

Figure 2 is a, cross section view taken on the line 2 2 of Figure l.

Figure 3 is a cross section view taken on the line 3-3 of Figure l.

Figure 4 is a vertical cross section view of a guide channel and the post driving hammer slidably mounted therein, together with the drive mechananism for raising the hammer.

Figure 5 is a fragmentary view of the device, particularly of the novel interconnected brake ancl hammer raising and lowering mechanism operable by the lever.

Referring in detail to the drawings and first with particular reference to Figures 1 and 4, the device comprises a fixed elongated hammer guide channel II) for a fence post hammer I I.

The xed hammer guidev channel I0 comprises side walls I2 and I4 bent at substantially right angles to a back web I5 of the channel. Integrally formed from the edges of each of the side walls are oppositely facing pairs of ears IB and I1 and Iv and I9, respectively. Each of the ears has an opening in which is mounted an axle stud for rotatably supporting rollers 2 I. The peripheries of the rollers 2l overhang and contact the top edges and 26 of a second channel member 21, having side walls and 3I and a connecting elongated back web 32. This second channel 21 is the hammer carrier and is slightly smaller, but similar in shape to channel I'Il, so that the hammer carrier channel 21 may telescopically slide up and down within the larger channel I0 which is fixed to a support. At the top of channel 21 is mounted the hammer I I.

The channel IIl has side bracket plates and 36 for rigid attachment of the channel to a supporting platform 31, on which is mounted a drive motor 38. This motor has a power takeoff pulley 39, which drives a pulley 40 through a belt 4I. The pulley 40 in turn imparts power to a shaft on an end of Which is a bevel gear 46 in mesh with another gear 41 on a shaft 48 to which is keyed a sprocket wheel 50. The sprocket 50 drives a chain 5I, a larger sprocket wheel 52, and a shaft 53.

The shaft 53 is journalled in a pair of bearings 55 and 56, see Figure 5, mounted in aligned openings in the side bars 51 and 58 of a frame 50. Keyed to the shaft 53 between the side bars 51 and 58 is a friction drive wheel 6I. A portion of the rim of. this Wheel is mounted to be brought into Contact with the rear flat surface of the back web 32 of the movable hammer carrying channel 21. This contact is made possible by providing an elongated opening 63, see Figure 4, in the back web I5 of the fixed guide channel I0,

The entire frame is pivoted between elongated ears and 66, see Fig. 5, which ears are apertured to receive a bar 61 on which the frame Sli is pivotally mounted adjacent one end of the bars 51 and 58.

'I'he opposite end of the frame 60 has an integrally formed exterorly extending tongue 10, Across the tongue is mounted a cam shaft 1I in a pair of side bearing lugs 12 and 13, as shown in Fig. 5. slots 14 therein to permit limited lateral sliding movement of the cam shaft 1I.

Mounted on the cam shaft is a cam 15 and a link 16, the cam 15 being shaped with a high point adapted to depress the tongue 16 toward the back webs of the channel members I0 and 21, and the link 16 being pivoted to the end of a connecting rod 18, which rod 18 connects to a second link 19 on a second cam shaft 80 of a brake system hereafter to be described.

Between the outer end of the tongue 10, and

These lugs 12 and 13 have elongated the adjacent back web I5 of the channel I0, and coiled around a stud 8| carried by channel It, is a spring 82. One end of the coiled spring 82 seats against the back web I5 and the other end ag-ainst the adjacent face of the tongue lo, to thereby normally expand and tend to hold the tongue, and the top part of the frame E outwardly from the web I with the friction drive wheel 6I out of contact with the back web 32 of hammer .carrier channel 21. Thus even though the friction wheel is being driven by the motor 38 no raising movement will be imparted to the hammer until the cam 15 moves the tongue against the tension of the spring .82,

and the periphery or rim of the friction drive wheel 69 contacts the back web 32 of the hammer carrier 21.

The cam shaft 1I is rotated or oscillated by connecting rod 18, which is actuated by a hand lever 35. The hand lever 85 is mounted in a coupiirig 8.6 onthe end of the second lcam shaft 8o, and on `which is .also mounted a brake actuator cam 81, see Figure 5. The second cam shaft 80 isjournaHed for turning A in the wall of a brake housing., see Fig. 1.

The housing'is fastened to the side of the fixed channel I0, around ,an elongated aperture in the side wall of the channel It, the brake shoe 93 `may be force-d by spring tension forwardly into braking contact with the side wall 3i of the l hammer carrying channel 2,1, see Fig. 3.

The brake shoe 93 is on a carrier plate 913 secured to the ends of a pair of aligned parallel brake rods 95 and 95. The rods extend through openings in a fixed plate :91 and a movable equali izerplate -98 coupled at its ends 4to the rods by .couplings 99 and Iil. Interposed between the brake shoe plate 94 and the fixed plate 91 and coiled around the brake rods are coiled springs UJI `and m2, The springs are under tension and normally tendito return to their expanded positions, so as to hold the brake against the side Wall 3l of the hammer carrier l21,. When the high point of the cam 81 contacts and presses against `the fixed plate 91 it compresses the springs further, thereby disengaging the brake shoe.

Operation In operation the platform 31 may be attached to a vehicle, such as a truck, not shown. When the hammer il is positioned over the end of the fence post, not shown, the driving action of the hammer Il is regulated by my novel interconnected brake and drive arrangement, by the raising or lowering of the hand lever 85 after the motor 38 has been started.

For example, by pushing the hand lever 8-5 way down it automatically releases the brake 93 and at the same time moves cam through connecting rod 18, thus pushing the friction drive wheel in against the hack web 32 of the movable hammer carrier channel 21, thereby raising the hammer I I. When the hammer is raised to a desired height above the top end of a fence post, -a release oi pressure on the hand lever 85 moves'cam "i5 back, so that coil `spring 82 pushes the tongue l@ and the irame with friction wheel 6I back allowing 'the hammer l I to fall.

The hammer il may be stopped in any position by applying the brake 9,3. The brake is applied by releasing the hand lever 85 from a raised position, which allowsthe brake shoe 93 to move into frictional holding engagement with the side wall 3l of the .hammer Achannel .21, while'simultaneously the connecting rod 18 moves the lower cam 15 back to cause release of drive wheel 6|.

Thus, by moving the single control lever 85, the operator can raise the hammer to any desired height, and can also stop the hammer in any position; Whereas, in the old style post driver there was no Way of regulating the length of the stroke or drop of the hammer.

While the several features of my invention are mor-.e or less specifically described, I Wish it understood that various changes may be resorted to within the scc-pe of the appended claims.

What I claim is:

l. Apparatus of the character described, comprising a vertical guide, a sliding member carried thereby, a driving head carried by the member, an oscillatable member carried by the guide,

, rotary driving means carried by the oscillatable member for driving connection with said sliding member when the oscillatable member is moved in one direction, a movable thrustmeans adapted to engage and move the oscillatablemember in the said one direction, a movable braking element supported by lthe guide for engagement with the sliding member to secure the latter against movement, and alink and rod coupling between the thrust mean-s and the braking element which upon movement to release `position transmits movement of the braking means to the thrust means to cause said oscillatable member to assume either of two positions, one of such positions maintaining the driving `means free of driving connection with the sliding member and the other position establishing driving connection between the driving means and the sliding member.

2. A post driving apparatus of the character stated comprising -a xed vertical guide, a slide member supported by the guide for vertical movement, a hammer carried by the slide member, a friction brake secured to the vertical guide and movably supported for frictional contact with the slide member, means normally urging movement of the friction brake into operative engagement with the sliding member, means for eiecting movement of the brake away from the slide member, a constantly rotating friction wheel supported upon the guide for rocking movement relative to the slide member, the friction wheel when rocked in one direction having driving connection with the slide member, means constantly urging movement of the friction wheel away from the slide member, a thrust means for effecting movement of the friction wheel into driving connection with the slide member, an operative coupling between the friction .brake moving means and said thrust member and a control lever for simultaneously effecting movement through said operative coupling of the thrust means and the brake moving means whereby the friction brake may be selectively appled and released and the friction wheel may be selectively engaged with and disengaged from the slide member.

3. Apparatus of the character described comprising a suitably supported guide member, va sliding member operatively engaged therewith for up and down movement, a hammer head carried by the sliding member, the sliding member and head dropping by gravity, a constantly moving rotatable means supported for movement relative to the sliding member for engaging the same and applying up thrust thereto, resilient means constantly urging movement of the'rotatable means away from engagement with the sliding member, a movable thrust means for urging movement of the rotatable means into engagement with the sliding member against the resilient means, a friction brake carried by the guide member for contact with the sliding member, resilient means constantly urging movement of the brake in one direction relative to the sliding member, a movable thrust means for urging movement of the brake in the opposite direction, a coupling between the two thrust means by which the two thrust means may 4be actuated si- 'f multaneously, and an operating member connected with one thrust means.

4. Apparatus of the character described, comprising a suitably supported guide member of channel form having a web portion and side flanges, a slide member of channel form disposed within the guide for movement between said anges, a hammer carried by the sliding member, a constantly rotating friction wheel supported by the guide for oscillatory movement into and out of driving contact with the sliding member, spring means normally urging movement of the wheel out of driving Contact with the sliding member, oscillatable thrust means adapted when turned in one direction for moving the friction wheel into driving connection with the sliding member, said guide having one ange thereof provided with an opening across which a portion of the sliding member moves, a friction brake supported for movement through said opening into braking contact with the sliding member, spring means normally urging movement of the friction brake in one direction, an 4oscillatable thrust means adapted when oscillated in one direction to effect movement of the vfriction brake in the opposite direction against the spring means,

a rigid coupling between the two thrust means,r

REFERENCES CITED The following references are of record in the le of this patent:

UNITED STATES PATENTS Number Name Date 2,040,668 Nichols May 12, 1936 2,378,131 Dirksen June 12, 1945 2,339,190 Kelly Apr. 30, 1946

Patent Citations
Cited PatentFiling datePublication dateApplicantTitle
US2040668 *Oct 11, 1934May 12, 1936Nichols William HPile driving attachment
US2339190 *Apr 29, 1943Jan 11, 1944Drummondville Cotton Company LTape lifting device and spindle brake mechanism
US2378131 *Jul 8, 1944Jun 12, 1945Beesley Harold GPost driver
Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US2593186 *Dec 31, 1949Apr 15, 1952Richard F BlanchfieldStake or post driver
US2940267 *Apr 27, 1953Jun 14, 1960Shaver Glenn FPost driver and puller
US2983323 *Apr 6, 1959May 9, 1961Whitney Clarence KApparatus for driving well points
US3205952 *Nov 13, 1961Sep 14, 1965Noble L SicottePortable well-driving rig
US3207236 *Apr 15, 1963Sep 21, 1965Shriner Clyde EPost driver
US3230781 *Nov 9, 1962Jan 25, 1966William DubilierAutomatic impact assembly
US3700047 *May 11, 1971Oct 24, 1972Gartner Michael AFence post driver
US4042036 *May 23, 1975Aug 16, 1977Smith James EElectric impact tool
US4129240 *Jul 5, 1977Dec 12, 1978Duo-Fast CorporationElectric nailer
US4204622 *Apr 8, 1977May 27, 1980Cunningham James DElectric impact tool
US4323127 *Mar 9, 1979Apr 6, 1982Cunningham James DElectrically operated impact tool
US7997467 *Sep 13, 2007Aug 16, 2011Makita CorporationElectric driving tool
U.S. Classification173/53, 173/124
International ClassificationE04H17/26
Cooperative ClassificationE04H17/263
European ClassificationE04H17/26B1