COVER FOR ATTACHMENT ARM

- MARSHALL TOWN COMPANY

The present invention is a cover for an attachment portion of a power trowel. The cover includes a cap portion and an attachment portion. The cap portion houses the bolts that attach the blades to the blade attachment member. The attachment portion is connected to the cap portion and depends therefrom. The attachment portion includes a pair of semi-circular members that depend from the cap portion and are used to couple the cover to the attachment portion.

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Description
CROSS-REFERENCE TO RELATED APPLICATIONS

Not applicable.

STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT

Not applicable.

BACKGROUND OF THE INVENTION

The present invention provides a cover for a power trowel and more specifically a cover for the blade attachment member and hardware of a power trowel.

Power trowels are used for both floating and finishing large slabs of concrete. Compared to ordinary hand tools, power trowels significantly increase production and reduce costs by their ability to cover more square footage of slab area per day. At the same time, they improve the quality of the concrete surface and help maintain flatness of the slab. Power trowels are divided into two styles, walk-behind and ride-on. Walk-behind power trowels typically have a rotor with four blades, are powered by a gasoline engine, and are available in 30-, 36- and 48-inch diameters. The blades of power trowels are bolted to a blade attachment member which is, in turn, coupled to the rotor. Ride-on power trowels typically have two rotors each with four or five blades, are powered by one or two gasoline engines and are available in 36- and 48-inch (single rotor diameter) models. Ride-on power trowels operate in two different configurations, overlapping and non-overlapping. The non-overlapping position of the blades may require higher torque and can accommodate the use of pans during the floating operation, as is understood by one of ordinary skill in the art. The overlapping position is often used at faster rotor speeds and provides seamless coverage during the finishing process.

In general, blades are interchangeable between most brands of walk-behind and ride-on power trowels as long as both the blades are the same size, i.e. 36- or 48-inch. Standard finish, combination, and float blades are made of high quality steel and bolted to the trowel arms. Once the blades wear out or a different type of blade is desired by the user, the user simply unbolts the blade and attaches another. However, due to the fact that power trowels are used with concrete, the bolts that couple the blades to the blade attachment member can become covered with hardened concrete and are sometimes difficult to remove.

BRIEF SUMMARY OF THE INVENTION

Accordingly, the present invention provides a cover for a blade attachment member and hardware of a power trowel. More specifically, the present invention discloses a cover for covering a plurality of fasteners that attach a plurality of blades to the blade attachment members. The covers are attached to the blade attachment members in an effort to keep the bolts free from concrete buildup thereby allowing the user to easily remove the bolts to change blades.

The cover includes a cap portion and an attachment portion. The cap portion includes a top surface and a pair of side walls that depend downwardly therefrom. The cap portion houses the bolts that attach the blades to the blade attachment member. The cap portion includes a flared portion that is connected to the cap portion. Specifically, the flared portion contains a pair of angled side walls that are coupled to the pair of side walls and depend therefrom. The angled side walls depend outwardly and downwardly from the side walls. The attachment portion is connected to the flared portion. The attachment portion includes a pair of semi-circular members that depend from the angled sidewalls.

As described above, the cover attaches to the blade attachment member and is used to cover the bolts that attach the blades to the blade attachment members.

Additional aspects of invention, together with the advantages and novel features appurtenant thereto, will be set forth in part in the description which follows, and in part will become apparent to those skilled in the art upon examination of the following, or may be learned from the practice of the invention. The objects and advantages of the invention may be realized and attained by means, instrumentalities and combinations particularly pointed out in the appended claims.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING

In the accompanying drawings which form a part of the specification and which are to be read in conjunction therewith, and in which like reference numerals are used to indicate like parts in the various views:

FIG. 1 is a perspective view showing a walk-behind power trowel;

FIG. 2 is a bottom plan view of the walk-behind power trowel of FIG. 1 showing a rotor, a plurality of blade attachment members, and a plurality of blades;

FIG. 3 is an exploded, perspective view of the blade attachment members, the blades, and the cover;

FIG. 4 is an enlarged, exploded, cross-sectional view of the blade attachment member, blade, and a blade attachment cover taken along the line 4-4;

FIG. 5 is a view similar to FIG. 4 but with the blade attachment cover attached to the blade attachment member;

FIG. 6 is a view similar to FIG. 4, but showing an additional embodiment of a blade attachment cover having a positioning member;

FIG. 7 is a view similar to FIG. 6 of an additional embodiment of a blade attachment cover, showing an additional embodiment of a positioning member;

FIG. 8 is a view of an additional embodiment of a blade attachment cover showing an alternate cross-section; and

FIG. 9 is a view of an additional embodiment of a blade attachment cover showing an alternate cross-section.

DETAILED DESCRIPTION OF THE INVENTION

With initial reference to FIG. 1, a walk-behind power trowel is generally indicated by reference numeral 10. The walking power trowel is a common item known to those of ordinary skill in the art. As seen in FIGS. 1 and 2, the trowel 10 is equipped with, among other things, a gas powered motor 12, a steering mechanism 14, a rotor 16, a blade guard 18, a plurality of blade attachment members 20 that attach a plurality of blades 22, and a plurality of blade attachment covers 24. The rotor 16 is coupled to the motor 12 and rotates the blades 22 when the power trowel 10 is turned on.

Referring now to FIGS. 3-6, the blade attachment members 20 include an arm 26 and an attachment portion 28. As shown in FIG. 2, the attachment portion 28, not shown, is used to couple the blade attachment members 20 with the rotor 16. The blade attachment members 20 extend outwardly from the rotor 16. Referring again to FIGS. 3-5, the arm 26 is an elongate member generally having a hexagonal cross-section. However it should be understood by one of ordinary skill in the art that any suitable cross-section may be used. The hexagonal cross-section of the arm 26 provides a plurality of surfaces. Specifically, the arm has an upper surface 30, a pair of upper angled sidewalls 32, a pair of lower angled sidewalls 34, and a lower surface 36. The upper and lower angled sidewalls 32, 34 converge at a point 38. The arm 26 further contains a plurality of apertures 40 that extend from the upper surface 30 to the lower surface 36. The apertures 40 are spaced apart and receive a plurality of bolts 42 to couple the blade 22 thereto.

The blades 22 include a planar surface 44 and a mounting rail 46. The mounting rail 46 is coupled to the planar surface 44 by rivets 48. However, it should be understood that any suitable coupling method may be used. The mounting rail 46 contains a plurality of threaded apertures 50 that receive the bolts 42 to couple the blade 22 to the blade attachment members 20. The lower surface 36 of the arm 26 rests on the mounting rail 46 when the blade 22 is coupled to the arm 26.

Referring now to FIGS. 4 and 5, the cover 24 will be discussed. The cover 24 is preferably formed from molded polyvinylchloride (PVC) or high density polyethylene (HDPE). However, it should be understood that any suitable material may be used and that the cover can be extruded to form a single piece or may be multiple pieces coupled together. The cover 24 is an integral elongate member that is used to conceal the bolts 42 that attach the blade 22 to the blade attachment member 20. The cover 24 includes a cap portion 52, and an attachment portion 56. The cap portion 52 extends the entire length of the cover 24. The cap portion 52 also includes a flared portion 54. The cap portion 52 contains a top surface 58 and first and second side walls 60, 62. The top surface 58 contains first and second sides 64, 66. The first and second side walls 60, 62 each contain upper and lower portions 68, 70, 72, 74 respectively. The upper portion 68 of the first side wall 60 is connected to the first side 64 of the top surface 58 and depends therefrom. The upper portion 72 of the second side wall 62 is connected to the second side 66 of the top surface 58 and depends therefrom. The first and second side walls 60, 62 depend downwardly from the top surface 58. The first and second side walls 60, 62 depend generally perpendicularly from the top surface 58. As seen in FIG. 4, the first and second side walls 60, 62 along with the top surface 58 define a cavity 76 that provides a space for the heads of the bolts 42 to remain out of contact with the concrete.

The flared portion 54 includes first and second angled walls 78, 80 each having upper and lower portions 82, 84, 86, 88. The upper portions 82, 86 of the first and second angled walls 78, 80 are connected to the lower portions 70, 74 of the first and second side walls 60, 62 and depend therefrom. The first and second angled walls 78, 80 depend outwardly and downwardly from the first and second sidewalls 60, 62 of the cap portion 52.

The attachment portion 56 depends from the flared portion 54. The attachment portion 56 includes a pair of semi-circular members 90. An upper portion of the semi-circular member 90 depends from the lower portions 84, 88 of the first and second angled walls 78, 80 at a joint 92.

To attach the covers 24 to the arms 26 of the blade attachment members 20, the user simply slides the cover 24 onto the arm 26. Initially, the semi-circular members 90 of the attachment portion 56 contact the upper angled sidewalls 32. As the user continues to push downwardly on the covers 24, the flared portions 54 move slightly outwardly until the semi-circular members 90 of the attachment portion 56 pass the point 38 where the upper and lower angled sidewalls 32, 34 converge. Once the semi-circular members 90 of the attachment portion 56 pass the point 38 of the arm 26, the joint 92 between the flared portion 54 and the attachment portion 56 receives the point 38. The flared portions 54 of the cover 24 rest on the pair of upper angled sidewalls 32. As such, the attachment portions 56 hold the cover 24 in place and the bolts 42 reside within the cavity 76.

FIG. 6 shows an additional embodiment of a cover 24a of the present invention. The cover 24a is the same as cover 24 with the exception that cover 24a contains a downwardly depending positioning member 96. The positioning member 96 depends downwardly from an underside 100 of the top surface 58. The positioning member 96 is located inwardly of the middle bolt 42. As such, when the trowel 10 rotates during use, the positioning member 96 prevents the cover 24a from sliding off the arm 26.

FIG. 7 shows an additional embodiment of a cover 24b of the present invention. The cover 24b is the same as cover 24 with the exception that cover 24b contains a positioning pin 102. The pin 102 is received in a pair of holes, not shown, in the first and second sidewalls 60, 62. The pin 102 is located inwardly of the middle bolt 42. As such, when the trowel 10 rotates during use, the pin 102 prevents the cover 24b from sliding off the arm 26.

FIG. 8, shows an additional embodiment of a cover 104 of the present invention. The cover 104 includes a cap portion 106 and an attachment portion 108. The cap portion 106 contains a top surface 110 and first and second side walls 112, 114. The top surface 110 contains first and second sides 116, 118. The first and second side walls 112, 114 each contain upper and lower portions 120, 122, 124, 126 respectively. The upper portion 120 of the first side wall 112 is connected to the first side 116 of the top surface 110. The upper portion 124 of the second side wall 114 is connected to the second side 118 of the top surface 110. The first and second side walls 112, 114 depend downwardly from the top surface 110. The first and second side walls 112, 114 depend generally perpendicularly from the top surface 110.

The attachment portion 108 depends from the cap portion 106. The attachment portion 108 includes a pair of semi-circular members 128. An upper portion of the semi-circular member 128 depends from the lower portions 122, 126 of the first and second side walls 112, 114 at a joint 130.

FIG. 9 shows an additional embodiment of a cover 132 of the present invention. The cover 132 includes a cap portion 134 and an attachment portion 136. The cap portion 134 contains a dome 138 and first and second side walls 140, 142. The dome 138 is semi-circular and contains first and second sides 144, 146. The first and second side walls 140, 142 depend downwardly from first and second sides 144, 146 of the dome 138.

The attachment portion 136 depends from the cap portion 134. The attachment portion 136 includes a pair of semi-circular members 148. An upper portion of the semi-circular member 148 depends from the first and second side walls 140, 142 at a joint 150.

It should be understood that the embodiments in FIGS. 8 and 9 may also contain a positioning member as discussed above with respect to FIGS. 6 and 7.

The present invention has been described in relation to particular embodiments, which are intended in all respects to be illustrative rather than restrictive. Alternative embodiments will become apparent to those skilled in the art to which the present invention pertains without departing from its scope.

It will be seen from the foregoing that this invention is one well adapted to attain the ends and objects set forth above, and to attain other advantages, which are obvious and inherent in the device. It will be understood that certain features and subcombinations are of utility and may be employed without reference to other features and subcombinations. This is contemplated. It will be appreciated by persons skilled in the art that the present invention is not limited to what has been particularly shown and described hereinabove. Rather, all matter herein set forth or shown in the accompanying drawings is to be interpreted as illustrative and not limiting.

Claims

1. A cover for an attachment portion of a power trowel, the cover comprising:

a cap portion, the cap portion having a flared portion depending downwardly from the cap portion; and
an attachment portion depending inwardly from the flared portion.

2. The cover of claim 1, wherein the cap portion includes an upper portion having a pair of edges and a pair of sidewalls depending downwardly from each edge

3. The cover of claim 2, wherein the flared portion includes a pair of angled sidewalls, the pair of angled sidewalls having an upper edge and a lower edge, the upper edge depending outwardly at an angle from the pair of sidewalls.

4. The cover of claim 3, wherein the attachment portion includes a pair of semi-circular members depending inwardly from the lower edge of the angled sidewalls.

5. The cover of claim 4, wherein the cap portion includes a positioning member.

6. The cover of claim 5, wherein the positioning member depends downwardly from a lower surface of the upper portion of the cap.

7. The cover of claim 5, wherein the positioning member is a pin, the pin being received in a pair of holes in the side walls of the cap portion.

8. A cover for an attachment portion of a power trowel, the cover comprising:

a cap portion, and
an attachment portion depending inwardly with the cap portion.

9. The cover of claim 8, wherein the attachment portion includes a pair of semi-circular members, the pair of semicircular members depending from the cap portion at a joint.

10. The cover of claim 9, wherein the cap portion includes an upper portion having a pair of edges and a pair of sidewalls depending downwardly from each edge.

11. The cover of claim 9, wherein the upper portion is a dome.

12. The cover of claim 11, wherein the cap portion includes a positioning member.

13. The cover of claim 12, wherein the positioning member depends downwardly from a lower surface of the upper portion of the cap.

14. The cover of claim 5, wherein the positioning member is a pin, the pin being received in a pair of holes in the upper portion of the cap portion.

15. A cover for an attachment portion of a power trowel, the cover comprising:

a right side;
a left side depending from the right side, the left side including: a top surface; a first member depending downwardly from the top surface; a second member depending outwardly at a angle from the first member; and a third member depending inwardly from the second member, the third member being semi-circular;
wherein the right side is a mirror image of the left side.
Patent History
Publication number: 20080101861
Type: Application
Filed: Oct 31, 2006
Publication Date: May 1, 2008
Applicant: MARSHALL TOWN COMPANY (MARSHALLTOWN, IA)
Inventors: Matt L. Beard (Cave Springs, AR), Troy Don Thurber (Bentonville, AR)
Application Number: 11/554,976
Classifications
Current U.S. Class: Tool Rotating In Horizontal Plane (404/112)
International Classification: E01C 19/22 (20060101);