Abstract: It is placed in a stationary manner in the top part of the machine and has a sharpening wheel (18) as well as a polishing device of the blade that eliminates the rough edges produced in sharpening.It has a frame (1) that incorporates a cover (3) that is subject to being collapsed in order to allow the unit to be cleaned. In the bottom the cover (3) incorporates a support fastened by means of a body (9) which is passed through by a central hole through which a shaft (12) passes whose top end incorporates a control (13) and in the bottom thereof the sharpening wheel (18) the shaft (12) being aided by a spring (14) whereby upon turning the control (13) the movement of the sharpening wheel (18) is produced until it makes contact with the cutting blade (2.) Upon releasing the control (13) the sharpening wheel returns to its original position, the cutting blade (2) remaining protected in the entire process.