Device for driving nails and similar fastening elements

DETAILED DESCRIPTION OF THE INVENTION In FIG.
1 a device for driving fastening elements is illustrated including a housing 1, a motor, however, only the drive shaft 2 from the motor is shown for reasons of simplicity, and a rotatable gear unit 3, for converting rotational movement into generally rectilinear driving motion for a driver rod 4.
The driver rod 4 is made up of a head 5 located in the upper portion of the housing shown in FIG.
1 and a shaft or ram 6 extending downwardly from the head for driving nails 7 fed in a magazine to an outlet 27.
The nails 7 are driven individually by the device into a workpiece, not shown.
During the driving operation, driver rod 4 is driven forwardly, or downwardly as viewed in FIG.
1, against a nail 7 axially aligned with the shaft 6.
The rectilinear driving or stroke motion of the driver rod 4 is provided by a carrier 8 in the form of a crank pin.
Carrier 8 is located on the front side, note FIG.
1, of a planet pinion 9 of the gear unit 3, the front side faces the driver rod 4.
Planet pinion 9 is rotatably supported on a substantially disk-shaped driving element 11 and is in meshed engagement with a hollow gear wheel 12.
The gear wheel 12 is secured in the housing 1 so that it does not rotate.
Further, a support gear 13 is also rotatably mounted on the driving element 11 diametrically opposite the planet pinion 9.
The support gear 13 is also in meshed engagement with the inside surface of the hollow gear wheel 12.
Planet pinion 9 and the support gear 13 is each supported on a pin 14, 15 positioned on the driving element 11 and each is provided with a wheel rim 16, 17 movable along a smooth circular path 18 on the hollow gear wheel 12.
Driving element 11 is supported in the housing 1 so that it rotates about its central axis.
Its central axis is defined by a shaft stub 19 and a pinion 21 is fixed to the shaft stub.
Another pinion 22 on the drive shaft 2 of the motor is in meshed engagement with the pinion 21 on the stub.
The pitch diameter of the planet pinion 9 corresponds to half of the pitch diameter of the hollow gear wheel 12