A power operated rotary knife including an annular rotary knife blade supported for rotation in a blade housing. The rotary knife blade including a body and a blade section extending from the body. The body includes an outer wall including an arcuate surface having an upper region extending from a first upper end portion to a second intermediate portion and a lower region extending from the second intermediate portion to a third lower end portion. A plurality of gear teeth extend downwardly from the upper end of the body, each of the plurality of gear teeth including an outer peripheral face forming a portion of the upper region of the arcuate surface of the outer wall. The body outer wall includes a bearing surface having a lower bearing face in the lower region of the arcuate surface and an upper bearing face in the upper region of the arcuate surface.

A controller 50 is disposed to the front relative to a rotation shaft 11d of an electric motor 11 above a base 2, so as to be tilted in the up-to-down direction as it extends frontward.

A blade housing assembly for a power operated rotary knife including a split blade housing and a cam mechanism for changing a blade housing diameter between blade supporting and blade changing positions. The split blade housing includes an annular blade support section, a mounting section and a split extending through the mounting section and an inner wall of the blade support section and defining a split distance between first and second circumferential ends of the inner wall. The split includes a radial split section and an angled split section adjacent the inner wall. The mounting section includes first and second body portions on opposite sides of the split. The cam mechanism includes a cam plate bridging the first and second body portions and a cam member rotatably supported by the cam plate. The cam member is rotatable between closed and open positions to change the blade housing diameter.

The invention relates to a rotary cutter (10) with an exchangeable blade (33), which enables the blade (33) to be replaced easily with little risk of injury and can be used in a variety of ways. The rotary cutter (10) comprises a handle (20) and a blade holder (30) which is detachably connected to the handle (20). A solid casing of the blade holder (30) takes at least half of the blade (33) within it (FIG. 1).

A power operated rotary knife including an annular rotary knife blade supported for rotation in a blade housing. The rotary knife blade including a body and a blade section extending from the body. The body includes an outer wall including an arcuate surface having an upper region extending from a first upper end portion to a second intermediate portion and a lower region extending from the second intermediate portion to a third lower end portion. A plurality of gear teeth extend downwardly from the upper end of the body, each of the plurality of gear teeth including an outer peripheral face forming a portion of the upper region of the arcuate surface of the outer wall. The body outer wall includes a bearing surface having a lower bearing face in the lower region of the arcuate surface and an upper bearing face in the upper region of the arcuate surface.

A safety blade for use with a knife assembly comprises a blade body, a bade attachment having a cutting edge and a top edge opposite the cutting edge, a blade attachment having a first half and a second half connected together via a hinge and extending beyond the top edge of the blade body to define a clamshell for receiving the blade body, and a handle adaptor having a handle engagement portion for removably securing the blade attachment to a handle.

A rotary knife includes a rotatable annular blade. The blade includes a blade wall presenting an annular inner surface terminating at a cutting edge. The annular inner surface includes a first section and a second section, with the first section extending from the cutting edge and the second section being located further from the cutting edge than the first section. The first and second sections define first and second angles, respectively, relative to an imaginary plane transverse to the axis about which blade rotates. The second angle is greater than the first angle.

A blade housing assembly for a power operated rotary knife including a split blade housing and a cam mechanism for changing a blade housing diameter between blade supporting and blade changing positions. The split blade housing includes an annular blade support section, a mounting section and a split extending through the mounting section and an inner wall of the blade support section and defining a split distance between first and second circumferential ends of the inner wall. The split includes a radial split section and an angled split section adjacent the inner wall. The mounting section includes first and second body portions on opposite sides of the split. The cam mechanism includes a cam plate bridging the first and second body portions and a cam member rotatably supported by the cam plate. The cam member is rotatable between closed and open positions to change the blade housing diameter.

An electric circular saw includes a saw blade, a motor, a housing, a bottom plate, a worm gear assembly and a power supply device. The saw blade is configured to rotate about a first axis. The motor has a motor shaft for driving the saw blade to rotate. The housing has an accommodating portion for accommodating the motor. The worm gear assembly realizes power transmission between the motor and the saw blade. The power supply device includes at least one battery pack to power the motor. The ratio of the nominal voltage of one battery pack to the weight of the electric circular saw is greater than or equal to 6 V/Kg and less than or equal to 12 V/Kg.

A rotary cutter insert can include a body configured to cover a first portion of a surface of a rotary blade. Further, the body of the rotary cutter insert can have an angled cutout configured to expose a second portion of the surface of the rotary blade so a rotary cutter can be used while the rotary cutter insert is in place. The rotary cutter insert reduces the area of exposed rotary blade that could potentially injure a user, thus making the rotary cutter significantly safer.