US1718002A - Power lift mechanism for plows - Google Patents

Description

' June 18, 1929. o. A. K. PRINTZ 1,718,002

POWER LIFT MECHANISM FOR PLOWS Filed Aug. 26, 1927 2 Sheets-Sheet l June 18, 1929. I o. A. K. PRINTZ POWER LIFT MECHANISM FOR FLOWS Filed Aug; 26, 192'! 2 Sheets-Sheet 2 (Z U5 x J. V

. 4 22 fig E.

[I l 5 I Z5 J 2- fix r l/ GAAwr/QG Patented June 18, 1929.

UNITED STATES PATENT ()FFICE.

POWER LIFT MECHANISM FOR FLOWS.

Application filed August 26, 1927, Serial No. 215,717, and in Sweden September 21, 1926.

This invention relates to improvements in power lift. mechanism for the frames of wheeled plows, of that type in which the plow frame is raised by power derived from a carrying wheel by means of a lifting arm pivoted at its one end to the plow frame and at its other end to a lifting disk which may be clutched to said carrying wheel to rotate therewith substantially to the extent of half a revolution and which, when thus rotated causes said arm to effect the lifting of the frame.

The invention has for its object to provide a simple and reliable power lift mechanism of the said type which is resistive to wear and easy to control.

' In the accompanying drawings,-

Figure 1 is a View partly in elevation and partly in section illustrating a plow according to this invention in working position with the lifting mechanism ready to commence a lifting operation.

Figure 2 is a view of the plow in elevated position.

Fig. 3 is a top-plan view of the lifting mechanism partly in section along the line 33 of Fig. 2;

Fig. 4 is a side elevation of the fork-shaped clutch lever of the lifting mechanism;

Fig. 5 is a top plan view of said lever;

Fig. 6 is a top plan View and Fig. 7 is an end view of the control lever arm.

It is to be noted that only those parts of the plow necessary for the understanding of the invention have been illustrated in the drawings.

In the drawings, the numeral 1 indicates the plow frame comprising suitably braced beams carrying the plow bases (not shown) at their downwardly bent ends. 2 indicates a bearing bracket secured to the frame for the accommodation of one carrying wheel crank axle 3 as well as of the straight lifting arm 4, the latter having its lower end pivoted to the lifting disk 5 at 6. Secured to the beams are, furthermore, two bearings for the accommodation of the other carrying wheel crank axle, though this is not shown in the drawing. The lifting disk 5 is mounted loosely on the spindle portion 7 of the crank axle 3, and loosely mounted on said spindle portion is also the carrying wheel 8. The hub of said wheel 8 is provided at its inner end with a hollow cylindrical portion 15 the lever 13 carries the roller 11 to engage the recesses 10 of the carrying wheel hub and, at 17, Fig. 4, a pivotally mounted bolt or rod 18 loosely engaging at its other end into a bracket 19 secured to .the lifting disk. Surrounding said bolt orsrod is a spring 20 tending to retain the lever 13 in either of two extreme positions corresponding to the disengaged and engaged state, respectively, of the lifting disk 5 relatively to the carrying wheel 8.

On the inner side of the wall 15 one end 21 of the lever 13 is shaped as a cam surface adapted to be operated by a roller 23 carried by the control lever 22 in order to cause the clutching of the roller lever 13 and thus also of the lifting disk 5 to the carrying wheel 8, whereas the other end 24 of the lever 13 is adapted in the lifting throw of the lifting disk to abut against a lug 25 on a housing 26 rigidly secured to the carrying wheel axle 3 to thereby effect the unclutching of the lifting disk from the carrying wheel. In order to limit the rotation of the lifting disk in its lifting throw a lug 27 is provided on the disk adapted to abut against the lug 25 on the housing 26. The lifting disk 5 is, furthermore, provided with a lug 28' adapted in the elevated position of the plow to be in close proximity to a roller 29 loosely mounted on an arm 30 pivoted to the side wall of the housing 26 which forms an extension of the control lever 22. The axes of the rollers 29 and 23 coincide the roller 23 being carried by an arm 31 which is pivoted at 32 to the arm 30. The roller 23 is situated in the path of the end 21 of lever 13 and may engage said end for the clutching of the lifting mechanism, whereas the roller 29 is situated to the side of said path but within reach of the lug 28 on which it acts to restore the plow to lowered position. A spring 33 inserted between the arms 30 and 31 acts to normally maintain the arm 31 in engagement with a lug 34 on the arm 30 while permitting the arm 31 to turn to allow the end 21 of lever 13 to pass, when the lifting disk is turned back in the lowering of the plow frame.

The operation is as follows:

When the plow frame is to be lifted, a pull is exerted on a rope 35 attached to the control lever 22 in the direction indicated by the arrow in Figs. 1 and 2. The control lever 22 which is rigidly connected to the arm 30 within the housing 26 will thus cause said arm 30 and with itthe arm 31 to turn until the roller 23 engagesthe end 21 of the lever 13 and turns same to cause the roller 11 to engage any of the recesses 10 in the cylindrical hub portion 9 of the carrying wheel 8. Said carrying wheel will now rotate the lifting disk 5 thereby causing the journal 6 of the lifting arm 4 to raise said arm and with it the plow frame 1. Towards the end of this movement the end 24 of the lever 13 will abut against the lug 25 of the housing 26 thereby causing the lever 13 in the continued rotation of the lifting disk to turn so as to disengage the roller 11 from the recess 10 with which it has been engaged thereby interrupting the transmission of power to the lifting disk. Substantially simultaneously with said interruption the lug 27 of the lifting disk abuts against the lug 25 causing the lifting disk to stop in a position in which that end of the lifting arm 4: mounted onthe journal 6 has passed the upper dead center position to some extent. 7

When the plow shall again be lowered a pull is again exerted on the rope 35 in the same direction as before whereby the arm 30 will be turned until the roller 29 engages the lug 28 and the lifting disk. A continued pull on the rope causes the arm 30 to turn the lifting disk backwardly until the journal 6 passes the upper dead center position allowing the lifting disk to restore to normal under the action of the plow frame when dropping by gravity to its working position.

The mechanism for limiting the drop of the plow frame falls outside the scope of the present invention but may in well knownmanner comprise a lug secured to the plow frame against which the carrying wheel axle 3 may drop in its rotation and which lug may be adjusted according to the depth of plowing desired.

What 1 claim is:

1. In a lifting mechanism for wheeled plows, the combination with aframe, of a crank axle mounted in said frame, a housing rigid with said axle, a carrying wheel loose on said axle, a recessed member rigid with said wheel, a lifting disk loose on said axle, an oscillatory lifting arm pivoted to said lifting disk and to said frame, of a lever pivotally mounted on said lifting disk, a roller on said lever to engage said recessed memher, a cam surface on said lever, and a control lever pivoted to said housing to act upon said cam surface to effect said engagement.

2. In a lifting mechanism for wheeled plows, the combination with a frame, of a crank axle mounted in said frame,a housing rigid with said crank axle, a carrying wheel loose on said axle, a recessed member rigid with said wheel, a lifting disk loose on said axle, an oscillatory lifting arm pivoted to said lifting disk and to said frame, a fork-shaped lever pivotally mounted intermediate its ends on said lifting disk, oneend of said lever being shaped as a cam surface, a roller on said lever to engage said recessed member, a control lever pivoted to said h0using, a roller on said control lever to act on said cam surface to effect said engagement, and a lug on said housing to be engaged by the other end of said fork-shaped lever to release said engagement. I

3. In a lifting mechanism for wheeled plows, the combination with a frame, of a crank axle mounted in said frame, a carrying wheel loose on said axle, a recessed member rigid with said wheel, a lifting disk loose on said axle, an oscillatory lifting arm pivoted to said lifting disk and to said frame, a housing rigid with "said axle, a control lever pivoted to said housing, a fork-shaped lever pivotally mounted intermediate its ends on said lifting disk, a roller on one end of said lever to engage said recessed member, a rod pivoted to the other end of said lever and engaging loosely said lifting disk, and a spring on said rod to maintain the lever in either of two end positions corresponding to engaged and disengaged state of the lifting disk. v

In testimony whereof I have signed my name.

OSCAR ADOLF KRISTIAN PRINTZ.

Images