Rotary cutter for a wood planing machine

A rotary cutter includes: an elongated polygonal shaft that defines a rotation axis, that has blade-mounting surfaces parallel to and surrounding the rotation axis, and that is formed with blade-aligning studs for aligning a blade, the blade-mounting surfaces being equidistant from the rotation axis, two adjacent ones of the blade-mounting surfaces defining an angle therebetween, the angles defined by the blade-mounting surfaces being equal; blade-fastening plates, each of which is attached to and cooperates with a respective one of the blade-mounting surfaces of the shaft to define a blade-receiving gap therebetween for receiving the blade; and fastening screws for fastening the blade to the respective one of the blade-mounting surfaces of the shaft.

CROSS-REFERENCE TO RELATED APPLICATION

This application claims priority of Taiwanese Application No. 093203292, filed on Mar. 05, 2004.

BACKGROUND OF THE INVENTION

1. Field of the Invention

This invention relates to a rotary cutter for a wood planing machine, more particularly to a rotary cutter including a polygonal shaft formed with blade-mounting surfaces for mounting of blades thereon.

2. Description of the Related Art

FIGS. 1 to 3illustrate a conventional wood planing machine that includes a base11, posts12standing upright from the base11, a cutter carriage13mounted movably on the posts12, and a rotary cutter14mounted rotatably on the cutter carriage13. The rotary cutter14includes a shaft15that is formed with a plurality of recesses153, and a plurality of blades16, each of which is mounted securely on the shaft15and each of which is disposed in a respective one of the recesses153. A pair of urging members154are disposed in each of the recesses153for adjustment of the depth of the blade16in the respective recess153. A pressing plate17and screw means19are used for pressing the blade16against a mounting wall155of the shaft15upon adjustment of the screw means19to abut against an opposite wall156of the shaft15opposite to the mounting wall155.

Since the recesses153are very narrow, tightening and loosening of the screw means19are relatively inconvenient during replacement of the blades16.

SUMMARY OF THE INVENTION

Therefore, the object of this invention is to provide a rotary cutter for a wood planing machine that is capable of overcoming the aforesaid drawback of the prior art.

According to the present invention, a rotary cutter for a wood planing machine includes: an elongated polygonal shaft that defines a rotation axis, that has axially extending blade-mounting surfaces parallel to and surrounding the rotation axis, and that is formed with threaded holes indented inwardly from each of the blade-mounting surfaces and aligned in an axial direction relative to the rotation axis, and blade-aligning studs projecting outwardly from each of the blade-mounting surfaces for aligning a blade during mounting of the blade on a respective one of the blade-mounting surfaces of the shaft, the blade-mounting surfaces being equidistant from the rotation axis, two adjacent ones of the blade-mounting surfaces defining an angle therebetween, the angles defined by the blade-mounting surfaces being equal; a plurality of elongated blade-fastening plates, each of which is attached to a respective one of the blade-mounting surfaces of the shaft, each of which is formed with a plurality of through-holes that are registered with the threaded holes at the respective one of the blade-mounting surfaces, and each of which cooperates with the respective one of the blade-mounting surfaces to define a blade-receiving gap therebetween for receiving the blade therein; and a plurality of fastening screws, each of which extends through a respective one of the through-holes in a respective one of the blade-fastening plates and the blade-receiving gap and engages threadedly a respective one of the threaded holes in the shaft so as to fasten the blade to the respective one of the blade-mounting surfaces of the shaft upon tightening of the fastening screws.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

FIGS. 4 and 5illustrate the preferred embodiment of a rotary cutter for a wood planing machine according to this invention.

The rotary cutter includes: an elongated polygonal shaft3that defines a rotation axis, that has axially extending blade-mounting surfaces31parallel to and surrounding the rotation axis, and that is formed with threaded holes33indented inwardly from each of the blade-mounting surfaces31and aligned in an axial direction relative to the rotation axis, and blade-aligning studs32projecting outwardly from each of the blade-mounting surfaces31for aligning a blade2during mounting of the blade2on a respective one of the blade-mounting surfaces31of the shaft3, the blade-mounting surfaces31being equidistant from the rotation axis, two adjacent ones of the blade-mounting surfaces31defining an angle θ therebetween, the angles θ defined by the blade-mounting surfaces31being equal; a plurality of elongated blade-fastening plates4, each of which is attached to a respective one of the blade-mounting surfaces31of the shaft3, each of which is formed with a plurality of through-holes41that are registered with the threaded holes33at the respective one of the blade-mounting surfaces31, and each of which has a blade-contacting portion42that cooperates with the respective one of the blade-mounting surfaces31to define a blade-receiving gap6therebetween for receiving the blade2therein; and a plurality of fastening screws5, each of which extends through a respective one of the through-holes41in a respective one of the blade-fastening plates4, a respective through-hole22in the blade2, and the blade-receiving gap6, and engages threadedly a respective one of the threaded holes33in the shaft3so as to fasten the blade2to the respective one of the blade-mounting surfaces31of the shaft3upon tightening of the fastening screws5.

In this embodiment, each of the blade-fastening plates4further has a shaft-contacting portion43that extends from the blade-contacting portion42and that abuts against the respective one of the blade-mounting surfaces31of the shaft3.

The blade2is formed with holes23respectively for extension of the blade-aligning studs32of the shaft3therethrough so as to facilitate alignment of the blade2on the respective one of the blade-mounting surfaces31of the shaft3.

Referring toFIG. 6, the blade2can be easily replaced by loosening the fastening screws5thereon, and removed subsequently from the blade-mounting surface31of the shaft3using a magnet7.

Since heads of the fastening screws5can be easily accessed, the blades2on the blade-mounting surfaces31of the shaft3can be easily replaced, thereby eliminating the drawback associated with the prior art.