Granted Patent B2

US 12,270,159 · App. 18/621,923 · Granted Apr 8, 2025

Inventor: Peter A. Ligman (Darien, WI)

Assignee: Ligchine International Corporation

E01C19/42

Abstract

Claims (34)

1. An apparatus for screeding concrete to produce a level finished surface comprising:

a frame assembly having a front end and rear ends, said frame assembly having a pair of spaced vertically oriented stabilization legs secured to the front end thereof, said spaced legs supporting a generally horizontal front member therebetween, and at least one stabilization leg secured to the rear end thereof;

an extendable boom assembly having front and rear ends, and an exterior boom section secured to said frame assembly proximate said rear end thereof and to a screed head at said front end, said extendable boom assembly adjustably mounted on said front member; and

an actuator secured between said front member and said extendable boom assembly to impart generally lateral motion thereto.

2. The apparatus of claim 1 wherein said actuator is a hydraulic actuator.

3. The apparatus of claim 1 wherein said actuator is a linear actuator.

4. The apparatus of claim 1 wherein said actuator is a hydraulic actuator.

5. The apparatus of claim 1 wherein said actuator is a linear actuator.

6. The apparatus of claim 1 comprising:

an actuator bracket secured to said actuator arm and to said swing boom assembly to impart lateral motion thereto.

7. The apparatus of claim 1 wherein said front member comprises a generally horizontal arcuate portion along a length thereof.

8. The apparatus of claim 7 wherein said boom assembly comprises:

a boom mounting plate secured to said exterior boom section and disposed between said exterior boom section and said front member; and

a plurality of roller bearings mounted for rotation to said boom mounting plate wherein said roller bearings contact said front member, thereby permitting said boom assembly to move laterally.

9. The apparatus of claim 8 comprising:

an actuator bracket secured to said actuator arm at a first end and to said boom mounting plate at a second end to impart lateral motion to said swing boom assembly.

10. The apparatus of claim 8 comprising:

a backing plate disposed below said boom mounting plate and secured in spaced relation thereto; and

a wear pad secured to said backing plate between said backing plate and an underside of said horizontal front member, whereby said backing plate contacts said horizontal front member.

11. The apparatus of claim 10 wherein said wear pad is comprised of ultra-high molecular weight polyethylene.

12. The apparatus of claim 10 comprising:

a plurality of compression springs disposed between said backing plate and said wear pad to provide generally upward spring force to said wear pad.

13. The apparatus of claim 1 comprising:

a pivot assembly including a generally cylindrical pivot post having a bottom and an open top, said bottom extending through an aperture in said frame assembly, and said top secured to said exterior boom section at a rear end thereof;

a keeper plate positioned below said frame aperture and secured to said pivot post bottom for rotatably securing said pivot post to said frame assembly.

14. The apparatus of claim 13 comprising:

a cylindrical pivot bushing sized to enclose said pivot post and positioned between said exterior boom section and said frame assembly.

15. The apparatus of claim 14 wherein said pivot bushing is comprised of ultra-high weight molecular polyethylene.

16. An apparatus for screeding concrete to produce a level finished surface comprising:

a frame assembly having a front end and rear end, said frame assembly having a pair of spaced vertically oriented stabilization legs secured to the front end thereof, said spaced legs supporting a generally horizontal arcuate front member therebetween, and at least one stabilization leg secured to the rear end thereof, each of said stabilization legs having a leveling actuator secured thereto for adjusting an elevation of said frame assembly and thereby said screed head;

an extendable boom assembly having front and rear ends, said front end adjustably secured to said front member;

an actuator with an extendable arm thereon, said actuator secured at a first end to said front member; and secured at a second end to said extendable boom assembly to impart generally lateral motion to said boom.

17. The apparatus of claim 16 comprising:

a wear pad disposed between said extendable boom assembly and said front member to facilitate lateral motion there between.

Assignments (1)

Continuity (4)

References Cited (256)

Cited By (3)

US 12,378,082 US 12,529,194 US 12,680,240