US3729765A - Self-tilting trowel for concrete - Google Patents

Abstract

A long-handled trowel device for leveling wet concrete includes mechanism attaching a handle to a trowel for automatically tipping the trowel along its far edge as a fulcrum during pull strokes and along its near edge on push strokes, so the trowel will always be properly oriented during troweling action. The automatic trowel-tipping mechanism comprises a carriage pivotally attached to the handle and moveable back and forth along a trackway rigidly secured to the top of the trowel. Carriage and trackway are interconnected by camming means, preferably made up of forward and rearward cam tracks sloping upwardly towards each other to peak intermediate the width of the trowel and forward and rearward cam followers placed in the respective cam tracks at similar positions with respect to the lengths of such tracks for simultaneous back and forth travel therein at mutually different ascending and descending levels.

Description

United States Patent 1 91 Peterson SELF-TILTING TROWEL FOR CONCRETE [75] Inventor: William D. Peterson, Kearns, Utah [73] Assignee: Weyher Construction Company, Salt Lake City, Utah [22] Filed: Dec. 23, 1971 [21] Appl.No.: 211,354

UNITED STATES PATENTS 973,688 10/1910 Nicholas ..l5/235.4 1,074,646 10/1913 Runner et al.. l5/235.8 2,834,199 5/1958 Freeman ....l5/235.8 2,999,261 9/1961 Lapham ..,.15/235.8 3,419,930 1/1969 Grunert ..306/l9 X FOREIGN PATENTS OR APPLICATIONS 9/1964 Great Britain ..15/235.4

[451 May 1, 1973 Primary ExaminerDaniel Blum Attorney-Philip A. Mallinckrodt [5 7] ABSTRACT A long-handled trowel device for leveling wet concrete includes mechanism attaching a handle to a trowel for automatically tipping the trowel along its far edge as a fulcrum during pull strokes and along its near edge on push strokes, so the trowel will always be properly oriented during troweling action. The automatic trowel-tipping mechanism comprises a carriage pivotally attached to the handle and moveable back and forth along a trackway rigidly secured to the top of the trowel. Carriage and trackway are interconnected by camming means, preferably made up of forward and rearward cam tracks sloping upwardly towards each other to peak intermediate the width of the trowel and forward and rearward cam followers placed in the respective cam tracks at similar positions with respect to the lengths of such tracks for simultaneous back and forth travel therein at mutually different ascending and descending levels.

7 Claims, 6 Drawing Figures Patented May 1, 1973 2 Sheets-Sheet 1 INVENTOR. WILLIAM D. PETERSON ATTORNEYS Patented May 1, 1973 3,729,765

' 2 Sheets-Sheet 2 FIG. 4

IOb lOc INVENTOR. WILLIAM D. PETERSON l l 20 I20 I00 20 IO 62 42 ATTO NEYS SELF-TILTING TROWEL FOR CONCRETE BACKGROUND OF THE INVENTION Field: The invention is in the field of concrete leveling devices, particularly long-handled trowel devices adapted for manual manipulation back and forth over expanses of freshly laid concrete.

State of the Art: There has long been recognition in this field of the useful arts that the trowel must automatically assume the correct orientation for both push and pull strokes of the handles, so as not to dig in and disrupt rather than level the wet concrete. Various ways have been proposed to accomplish this, see U.S. Pat. Nos. 973,688; 1,074,646; 2,833,188; 2,834,199; and 2,999,261. For one reason or another these proposed devices have not gone into general use and are not normally commercially available.

SUMMARY OF THE INVENTION In accordance with the invention a very effective working device having attractive commercial possibilities is provided, based on a simple and efficient camming arrangement between handle and trowel. Thus, the long handle is pivotally attached at one end to a carriage that is movable back and forth along a trackway rigidly secured to the top of the trowel. The carriage and the trackway are interconnected by camming means including forward and rearward cam tracks that are preferably provided as pairs of slots formed at opposite sides of the carriage in respective walls of an open box constituting the trackway. The

forward cam track and the rearward cam track at each side of the carriage slope upwardly toward each other to peak intermediate the width, i.e. intermediate the forward edge and the rearward edge, of the trowel. The camming means also includes forward and rearward cam followers placed in the respective cam tracks at similar positions with respect to the lengths of such tracks for simultaneous back and forth travel therein at mutually different ascending and descending levels. When the cam tracks are in the presently preferred form of slots formed at opposite sides of an open box trackway, as indicated above, the cam followers are preferably lugs projecting laterally from the carriage into sliding engagement with the respective cam track slots.

THE DRAWING A specific embodiment of long-handled trowel presently contemplated as the best mode of carrying out the invention is illustrated in the accompanying drawings in which:

FIG. 1 is a'fragmentary perspective view showing the handle-operated carriage in an intermediate position, with the trowel lying flat on a supporting surface;

FIG. 2, a different fragmentary perspective view drawn to a somewhat smaller scale and showing the positions of both carriage and trowel as the device is being pushed away from the operator over wet concrete during a troweling operation;

FIG. 3, a corresponding view showing the positions of both carriage and trowel as the device is being pulled toward the operator during the troweling operation;

FIG. 4, a fragmentary top plan view of the device as shown in FIG. 1, with a portion of the carriage broken out to show how the cam follower lugs are attached to the carriage in this instance;

FIG. 5, a longitudinal vertical section along the axis of the handle as taken on the line 5-5 of FIG. 4; and

FIG. 6, a vertical section, transverse with respect to the axis of the handle but longitudinal with respect to the trowel, taken on the line 66 of FIG. 4.

DETAILED DESCRIPTION OF THE ILLUSTRATED EMBODIMENT In the form illustrated, the device comprises an elongate trowel 10 having a longitudinal rib 10a as a raised median strip utilized as a mount for automatic troweltipping mechanism that serves to attach an elongate handle 11 to the trowel perpendicularly thereof. The trowel preferably has beaded forward and rearward edges 10b and 100, respectively.

The trowel-tipping mechanism comprises a carriage l2 and a trackway 13. In the present instance carriage 12 is formed from a length of structural steel channel and provided with an ear l4 upstanding from its back to which an end of handle 11 is pivotally secured by a clevis l5 and pivot pin bolt 16, enabling the handle to be thrown as desired for any given operation of the trowel but normally cinched tight so as to be fixed and non-pivotal during any given concrete-leveling operation of the trowel. Trackway 13 has a pair of mutually spaced, longitudinal trackway members 17, respectively, advantageously formed from structural steel angles as illustrated, which are rigidly held together by a pair of end plates 18, respectively, to provide an open box which slidably receives carriage 12 in the inverted channel orientation shown, with the channel legs 12a, respectively, directed downwardly. The slideway box sits astride median strip 10a, being secured thereto by bolts 19 and being steadied and reinforced in such securement by a pair of spaced, depending ribs 20,

respectively, that are attached, as by welding, to the undersides of angles 17.

Carriage 12 and trackway 13 are interconnected by camming means, which, in this instance, comprise a pair of forward slots 21 at opposite sides of the carriage in respective slideway members 17, and a pair of rearward slots ,22 also at opposite sides of the carriage and in respective slideway members 17. The forward and rearward slots in each slideway member slope upwardly toward each other and peak, see P, intermediate the longitudinal forward and rearward edges 10b and 10c, respectively, of the trowel. Although they may actually meet at the peak, it is preferred that they stop short of meeting, as illustrated.

Such camming means further comprise cam followers, which, in this instance, take the form of a pair of lugs 23 for the forward cam track slots 21, respectively, and a pair of lugs 24 for the rearward cam track slots 22, respectively. These lugs are placed in the respective slots at similar positions with respect to the lengths of the slots. Thus, when the lugs 23 are positioned forwardly in the slots 21, the lugs 24 will be positioned forwardly in the slots 22, and likewise with respect to rearward and intermediate positions as illustrated. As carriage 12 is moved back and forth in trackway 13, the pairs of lugs 23 and the pairs of lugs 24 will travel simultaneously back and forth in their respective pairs of slots 21 and 22 at mutually different ascending and descending levels, thereby tipping the trowel on its forward longitudinal edge b as a fulcrum, see FIG. 3, for back movement and on its rearward longitudinal edge 10c as a fulcrum, see FIG. 2, for forth movement.

In the illustrated construction, lugs 23 and 24 are provided by bolts, see FIGS. 4, 5, and 6, that are installed in receiving holes drilled at appropriate locations in legs 12a of carriage l2. Carriage 12 is first inserted between slideway members 17 of trackway l3 and the pairs of lug bolts 23 and of lug bolts 24 are then inserted and fastened securely in place by the nut portions 23a and 24a of such bolts.

Although the illustrated construction is convenient, economical, and durable, it should be realized that a variety of other specific constructions are possible within the generic preview of the claims which follow.

I claim:

1. A long-handled trowel device for leveling wet concrete and the like, comprising an elongate trowel; an elongate handle; and automatic trowel-tipping mechanism attaching the handle to the trowel, said automatic trowel-tipping .mechanism comprising a trackway extending transversely across the top of said trowel and rigidly secured thereto; a carriage moveable back and forth along said trackway and secured to said handle; and camming means interconnecting trackway and carriage said camming means comprising at least one forward cam track and one rearward cam track sloping upwardly toward each other to peak intermediate the longitudinal edges of the trowel; and cam followers for the forward and rearward cam tracks,

respectively, said cam followers being placed in the respective cam tracks at similar positions with respect to the lengths of such tracks for simultaneous back and forth travel therein at mutually different ascending and descending levels.

2. A device in accordance with claim 1, wherein the cam tracks are slots and the cam followers project into the slots.

3. A device in accordance with claim 1, wherein the cam tracks are formed in the trackway and the cam followers project from the carriage.

4. A device in accordance with claim 3, wherein the trackway has trackway members at opposite lateral sides of the carriage and the forward and rearward cam tracks are provided as a pair of forward cam tracks at opposite sides of the carriage in said trackway members, respectively, and a pair of rearward cam tracks also at opposite sides of the carriage in said trackway members, respectively.

5. A device in accordance with claim 4, wherein the trackway is formed as an elongate open box and the carriage is slideably fitted into said box for back and Y forth sliding movement therein.

6. A device in accordance with claim 5, wherein the trowel has a raised median strip extending longitudinally thereof and the trackway box is mounted astride said median strip.

7. A device in accordance with claim 6, wherein the trackway box has its trackway members formed from lengths of structural angles and the carriage is formed from an inverted length of structural channel.

Claims (7)

1. A long-handled trowel device for leveling wet concrete and the like, comprising an elongate trowel; an elongate handle; and automatic trowel-tipping mechanism attaching the handle to the trowel, said automatic trowel-tipping mechanism comprising a trackway extending transversely across the top of said trowel and rigidly secured thereto; a carriage moveable back and forth along said trackway and secured to said handle; and camming means interconnecting trackway and carriage said camming means comprising at least one forward cam track and one rearward cam track sloping upwardly toward each other to peak intermediate the longitudinal edges of the trowel; and cam followers for the forward and rearward cam tracks, respectively, said cam followers being placed in the respective cam tracks at similar positions with respect to the lengths of such tracks for simultaneous back and forth travel therein at mutually different ascending and descending levels.

2. A device in accordance with claim 1, wherein the cam tracks are slots and the cam followers project into the slots.

3. A device in accordance with claim 1, wherein the cam tracks are formed in the trackway and the cam followers project from the carriage.

4. A device in accordance with claim 3, wherein the trackway has trackway members at opposite lateral sides of the carriage and the forward and rearward cam tracks are provided as a pair of forward cam tracks at opposite sides of the carriage in said trackway members, respectively, and a pair of rearward cam tracks also at opposite sides of the carriage in said trackway members, respectively.

5. A device in accordance with claim 4, wherein the trackway is formed as an elongate open box and the carriage is slideably fitted into said box for back and forth sliding movement therein.

6. A device in accordance with claim 5, wherein the trowel has a raised median strip extending longitudinally thereof and the trackway box is mounted astride said median strip.

7. A device in accordance with claim 6, wherein the trackway box has its trackway members formed from lengths of structural angles and the carriage is formed from an inverted length of structural channel.

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