A chain saw unit has a sub-frame defining a plurality of mount locations and a plurality of operating components amongst which are at least: a) a battery operated motor; and b) a battery for operating the motor. The plurality of operating components is each operatively placed and maintained at one of the mount locations such that the sub-frame assembly and operatively placed operating components together make up at least part of a main operating unit to which a chain bar and cutting chain can be operatively assembled. The main operating unit has an exposed surface area. An outer housing assembly overlies the exposed surface area and defines an outermost exposed surface. The plurality of operating components are operatively maintained on the sub-frame assembly independently of the outer housing assembly.

A chain saw kit having a sub-frame assembly and a plurality of operating components, among which are at least a battery operated motor and battery. The sub-frame assembly is configured to define mount locations for the operating components so that the sub-frame assembly and operatively placed operating components make up at least a part of a main operating unit to which a chain bar and cutting chain can be assembled. A first outer housing assembly has at least a first outer housing part with a second outer housing assembly having at least a second outer housing part. The parts of the outer housing assemblies are interchangeably usable to allow selection of different overall size, shape, and/or appearance of chain saws based upon a common sub-frame assembly.

A chain saw kit having a sub-frame assembly and a plurality of operating components, among which are at least a battery operated motor and battery. The sub-frame assembly is configured to define mount locations for the operating components so that the sub-frame assembly and operatively placed operating components make up at least a part of a main operating unit to which a chain bar and cutting chain can be assembled. A first outer housing assembly has at least a first outer housing part with a second outer housing assembly having at least a second outer housing part. The parts of the outer housing assemblies are interchangeably usable to allow selection of different overall size, shape, and/or appearance of chain saws based upon a common sub-frame assembly.

A power tool has a sprocket wheel cover mounted on a housing and a guide bar secured between housing and sprocket wheel cover and having a guide groove for a saw chain. The guide bar has a guide slot extending in a longitudinal direction of the guide bar and guiding the guide bar on a guide element for longitudinal movement relative to the housing. The guide bar has a first exterior side extending in a first plane and facing the housing and a second exterior side extending in a second plane and facing the sprocket wheel cover. The guide bar has an oil supply opening extending from the second exterior side into the guide groove and connected by an oil supply channel with an oil supply device. The oil supply channel has a channel section separate from the guide bar and extending from the first to the second plane.

A power tool has a sprocket wheel cover mounted on a housing and a guide bar secured between housing and sprocket wheel cover and having a guide groove for a saw chain. The guide bar has a guide slot extending in a longitudinal direction of the guide bar and guiding the guide bar on a guide element for longitudinal movement relative to the housing. The guide bar has a first exterior side extending in a first plane and facing the housing and a second exterior side extending in a second plane and facing the sprocket wheel cover. The guide bar has an oil supply opening extending from the second exterior side into the guide groove and connected by an oil supply channel with an oil supply device. The oil supply channel has a channel section separate from the guide bar and extending from the first to the second plane.

A chain saw unit has a sub-frame defining a plurality of mount locations and a plurality of operating components including at least: a) a battery operated motor; and b) a battery for operating the motor. The plurality of operating components is each operatively placed and maintained at one of the mount locations such that the sub-frame assembly and operatively placed operating components together make up at least part of a main operating unit to which a chain bar and cutting chain can be operatively assembled. The main operating unit has an exposed surface area. An outer housing assembly overlies the exposed surface area and defines an outermost exposed surface. The plurality of operating, components are operatively maintained on the sub-frame assembly independently of the outer housing assembly.

A chain saw unit has a sub-frame defining a plurality of mount locations and a plurality of operating components including at least: a) a battery operated motor; and b) a battery for operating the motor. The plurality of operating components is each operatively placed and maintained at one of the mount locations such that the sub-frame assembly and operatively placed operating components together make up at least part of a main operating unit to which a chain bar and cutting chain can be operatively assembled. The main operating unit has an exposed surface area. An outer housing assembly overlies the exposed surface area and defines an outermost exposed surface. The plurality of operating, components are operatively maintained on the sub-frame assembly independently of the outer housing assembly.

A chain saw kit having a sub-frame assembly and a plurality of operating components, including at least a battery operated motor and battery. The sub-frame assembly is configured to define mount locations for the operating components so that the sub-frame assembly and operatively placed operating components make up at least a part of a main operating unit to which a chain bar and cutting chain can be assembled. A first outer housing assembly has at least a first outer housing part with a second outer housing assembly having at least a second outer housing part. The parts of the outer housing assemblies are interchangeably usable to allow selection of different overall size, shape, and/or appearance of chain saws based upon a common sub-frame assembly.

A chain saw kit having a sub-frame assembly and a plurality of operating components, including at least a battery operated motor and battery. The sub-frame assembly is configured to define mount locations for the operating components so that the sub-frame assembly and operatively placed operating components make up at least a part of a main operating unit to which a chain bar and cutting chain can be assembled. A first outer housing assembly has at least a first outer housing part with a second outer housing assembly having at least a second outer housing part. The parts of the outer housing assemblies are interchangeably usable to allow selection of different overall size, shape, and/or appearance of chain saws based upon a common sub-frame assembly.

A working machine has an oil groove communicating a pump chamber with a gear chamber, and a small amount of oil is delivered to the gear chamber when oil is discharged from the pump chamber. Thus, the oil adheres to the outer peripheral surface of a rotating pump shaft and is kept remaining between a pump case and the pump shaft. Therefore, the viscosity is increased and a pressure loss between the pump chamber and the gear chamber is increased. Accordingly, the airtightness can be maintained, and the stable and inexpensive oil pump mechanism requiring less man-hour can be realized without depending on the accuracy of a gap between the pump case and the pump shaft. Since oil is kept remaining on the outer peripheral surface of the pump shaft, it is possible to prevent the pump case from being worn out and to improve the durability of components.