US3291231A

US3291231A - Post hole digger

Info

Publication number: US3291231A
Application number: US421800A
Authority: US
Inventors: Andrew E Kammer
Original assignee: Individual
Current assignee: Individual
Priority date: 1964-12-29
Filing date: 1964-12-29
Publication date: 1966-12-13
Anticipated expiration: 1983-12-13

Description

Dec. 13, 1966 A. E. KAMMER 3,291,231

POST HOLE DIGGER Filed Dec. 29, 1964 INVENTOR.

M23550 ,6", XGVVMALZ United States Patent 3,291,231 POST HOLE BIGGER Andrew E. Kammer, 407 Eldert Lane, Brooklyn, N.Y. Filed Dec. 29, 1964, Ser. No. 421,800 3 Claims. (Cl. 175--170) This invention relates to a device for digging holes in the ground, particularly post holes or the like.

It is the principal object of this invention to provide a tool of improved design for forming cylindrical holes to a desired depth of desired proportions with ease and a minimum of labor, which does not pack the earth and which provides a post receiving hole of optimum dimensions with a minimum of soil handling.

Another object of this invention is to form the tool device as a cylindrical metal sleeve provided with a circumferential row .of earth cutting teeth at the lower edge of the sleeve, the upper end of the sleeve having formed therein diametrically opposed reverse bayonet-slots to removably receive a handle bar for operating the sleeve by rotating the same clockwise to effect its cutting function.

A further object of the invention is to provide interiorly of the sleeve and adjacent the cutting teeth a pair of diametrically opposed angularly related cutting blades that function to cut-out and support the earth core that is cut out by the device.

A still further object of the invention relates to the removal of the cut out earth core by the simple expedient of turning the sleeve upside down on its removal from the earth upon completion of its cutting operation by a counter-clockwise rotation, with the earth core contained therein, and simply dropping the earth core therefrom.

Further objects of the invention will appear as the description proceeds.

To the accomplishment of the above and related objects, my invention may be embodied in the form illustrated in the accompanying drawings, attention being called to the fact, however, that the drawings are illustrative only, and that change may be made in the specific construction illustrated and described within the scope of the appended claims.

FIGURE 1 is a perspective view of the digging device with handle bar positioned thereon.

FIGURE 2 is a vertical sectional view of the digging device taken on line 2-2, FIGURE 1, showing the sam in use.

FIGURE 3 is a bottom view of the digging device.

FIGURE 4 is a perspective view of one of the cutting blades.

FIGURE 5 illustrates the manner of discharging the earth core from the digging device.

Referring to the drawings, the post hole digging device consists of a cylindrical metal sleeve 12 having an outside diameter corresponding to the diameter of the post selected for use, it being understood that the digging device 10 may come in a variety of sizes each corresponding to the size of post used. Preferably the sleeve 12 is formed of sheet steel of a thickness of inch, and may be of any desired length. For general purposes, a length of 30 to 36 inches has been formed to be satisfactory for the sleeve 12, as Well as diameters of 4, 5 and 6 inches.

The sleeve 12, at its lower terminal end, is provided with a circumferential row of teeth 14 of a size and shape that will readily cut into the earth. Preferably the teeth 14 are deflected slightly radially outwardly, as shown, so as to cut a kerf in the soil of a diameter slightly greater than the diameter of the sleeve 12. This will prevent binding of the sleeve in the soil and will facilitate the easy removal of the sleeve from the soil upon the completion of the cutting operation.

The upper end of the sleeve 12 has formed therein a pair of bayonet slots 16 and 18, arranged diametrically opposite each other and reversely related, that is, the bottom horizontal portions of the bayonet slots extend 1n opposite directions. Adapted to removably fit within the bayonet slots 16, 18 in a handle bar 20, the intermediate portion thereof being engageable within the bayonet slots, as shown in FIGURES 1 and 2.

A pair of

like cutter blades

24, 26, are located interiorly of the sleeve 12 adjacent the teeth 14. Referring to FIG- URE 4, it is seen that the blade 24 consists of a blade portion 30 and a flanged or bracket portion 32. The blade portion 30 is formed flat and is provided with a transverse cutting edge 34 at its forward end. The rear end 36 of the blade is narrower than the front end. The outer side 38 of the blade 24 is curved to correspond with the cylindrical curvature of the sleeve 12, and depending from the curved side is the bracket portion 32 which is also correspondingly curved. Provided in the bracket portion 32 are openings 40 for receiving fastener elements such as rivets. The blade 26 is formed similar to the blade 24. Both

blades

24 and 26 are positioned substantially diametrically opposite each other and are each inclined downwardly towards the teeth 14 along a helical path in order to facilitate their entry and downward movement through the earth on clockwise rotation of the sleeve 12.

The

blades

24, 26 are so positioned that their leading cutting edges 34 are located slightly (not more than 4 inch) above the base of the saw teeth 14 as shown in FIGURE 2. Referring to FIGURE 3, it will be seen that the straight side edge 39 of each blade opposite its curved bracket portion 32 will in the attachment of the cutting blades to the sleeve lie parallel to each other and that the vertical plane of the cutting edge 34 of each blade will intersect the straight side edge of the other blade. The transverse cutting edge 34 of each blade provides the leading edge thereof as shown in FIGURE 3. The

blades

24, 26 are each secured to the inside wall of the sleeve 12 by rivets 43. If desired, the

blades

24, 26 may be welded direct to the sleeve 12.

With the handle bar 20 in position on the sleeve 12, a post hole is dug by the sleeve 12 when placed on the soil 46, see FIGURE 2. Rotation of the sleeve in a clockwise direction and the application of downward pressure on the handle bar 20 will cause the saw teeth 14 to cut a kerf in the soil. Downward movement of the sleeve 12 thus effected will subsequently cause the

blades

24, 26 to enter the soil and progress downwardly in a helical path until the desired depth of hole is reached. The

blades

24 and 26 function to break off the bottom of the core or plug of earth formed in the sleeve such that removal of the sleeve 12 with its core is easily effected by an upward pull on the handle bar accompanied if necessary, by rotating the sleeve counter-clockwise. On complete removal of the sleeve 12 from the soil, there is left therein a cylindrical hole for the reception of the post, and-the core or plug 48 is simply dropped out of the sleeve 12 when it is turned up-side-down as shown in FIGURE 5.

While certain novel features of my invention have been shown and described and are pointed out in the anneXed claims, it will be understood that various omissions, substitutions and changes in the forms and details of the device illustrated and in its operation can be made by those skilled in the art without departing from the spirit of the invention.

Having described my invention, what I claim as new and desire to secure by Letters Patent is:

1. A post hole digger device comprising:

(a) a cylindrical sleeve for coring, retaining and releasing soil,

(b) a circumferential row of cutting teeth on the lower terminal end of said sleeve,

(c) at least one cutting blade interiorly of said sleeve having a cutting edge adjacent the base of said cutting teeth,

(d) a handle bar removably connected to the upper end of said sleeve,

(e) said cutting teeth are each deflected outwardly of the outer cylindrical surface of said sleeve, and

(f) the removable connection of said handle bar with said sleeve comprising a pair of diametrically positioned reverse bayonet slots formed in the upper end of said sleeve and opening into the upper terminal end of said sleeve, whereby said handle bar is inserted horizontally simultaneously into both bayonet slots and retained therein by a slight turning movement,

(g) a fiat blade portion,

(h) a curved bracket portion corresponding in curvature to the inside cylindrical wall curvature of said sleeve,

(i) a leading cutting edge on said blade portion extending transversely thereof, and

(j) means rigidly securing the bracket portion of said cutting blade to the inside wall of said sleeve.

2. The post hole digger of claim 1, wherein:

(a) The fiat blade portion fthe cutting blade is inclined downwardly towards the cutting teeth such as to move downwardly into the soil along a helical path on clockwise rotative movement of said sleeve,

(b) said cutting blade being operative to cut the bottom of the earth core from the earth whereby to permit removal of the sleeve and core from the soil.

3. The post hole digger of claim 2, wherein:

(a) a pair of cutting blades are located within said sleeve and disposed in diametrically opposed relation with the leading cutting edge of each facing opposite portion of the inside wall surface of said sleeve,

(b) the rear edge of each blade portion being narrower than the leading cutting edge thereof, and

(c) the side edge of each blade opposite the curved bracket portion thereof being straight,

(d) whereby in the attachment of said cutting blades to the inside wall of said sleeve, said straight side edges of said blades will lie opposite each other in parallel relationship and the vertical plane of the leading cutting edge of each blade will intersect the straight side edge of the other blade.

References Cited by the Examiner UNITED STATES PATENTS 2,708,593 5/ 1955 Benoist 29450.7 2,854,219 9/1958 MacNeil 1754O4 FOREIGN PATENTS 5,419 5/ 1879 Germany.

HUGO O. SCHULZ, Primary Examiner.

GERALD M. FORLENZA, Examiner.

G. F. ABRAHAM, Assistant Examiner.

Claims

1. A POST HOLE DIGGER DEVICE COMPRISING: (A) A CYLINDRICAL SLEEVE FOR CORING, RETAINING AND RELEASING SOIL, (B) A CIRCUMFERENTIAL ROW OF CUTTING TEETH ON THE LOWER TERMINAL END OF SAID SLEEVE, (C) AT LEAST ONE CUTTING BLADE INTERIORLY OF SAID SLEEVE HAVING A CUTTING EDGE ADJACENT THE BASE OF SAID CUTTING TEETH, (D) A HANDLE BAR REMOVABLY CONNECTED TO THE UPPER END OF SAID SLEEVE, (E) SAID CUTTING TEETH ARE EACH DEFLECTED OUTWARDLY OF THE OUTER CYLINDRICAL SURFACE OF SAID SLEEVE, AND (F) THE REMOVABLY CONNECTION OF SAID HANDLE BAR WITH SAID SLEEVE COMPRISING A PAIR OF DIAMETRICALLY POSITIONED REVERSE BAYONET SLOTS FORMED IN THE UPPER TERMINAL OF SAID SLEEVE AND OPENING INTO THE UPPER TERMINAL END OF SAID SLEEVE, WHEREBY SAID HANDLE BAR IS INSERTED HORIZONTALLY SIMULTANEOUSLY INTO BOTH BAYONT SLOTS AND RETAINED THEREIN BY A SLIGHT TURNING MOVEMENT, (G) A FLAT BLADE PORTION, (H) A CURVED BRACKET PORTION CORRESPONDING IN CURVATURE TO THE INSIDE CYLINDRICAL WALL CURVATURE OF SAID SLEEVE, (I) A LEADING CUTTING EDGE ON THE SAID BLADE PORTION EXTENDING TRANSVERSELY THEREOF, AND (J) MEANS RIGIDLY SECURING THE BRACKET PORTION OF SAID CUTTING BLADE TO THE INSIDE WALL OF SAID SLEEVE.