An improved injection apparatus is disclosed comprised of a first motor and a second motor, each motor having a shaft. First and second needles are located substantially perpendicular to the first and second shafts, respectively. When the first and second shafts rotate, the first and second needles, respectively, move up and down. The first and second shaft rotate in opposite directions. The first needle and second needles can be surrounded by first and second needle tubes, respectively. The first and second needle tubes can be mounted to a device housing. The first and second needles each preferably has a portion that lies inside its needle tube and a portion that lies outside its needle tube. First and second sources of liquid and first and second conveying tubes are provided. The first and second conveying tubes are connected to the first and second needles, preferably at a side arm inside the respective needle tubes. The first and second needles are preferably hollow. Preferably liquid flows from the first source of liquid to the first conveying tube then into the hollow first needle. Similar liquid flow occurs for the second needle. The first and second conveying tubes are connected to first and second meters which measure how much liquid is being fed into the first and second needles from the first and second liquid sources.

A handheld tattoo machine with a low vibration drive unit and an offset, removable driven grip tube. The drive unit includes a rotatable drive shaft; a cam attached to the distal end of the shaft, the cam having a cam face at an angle to the longitudinal axis of the drive shaft; and a drive housing enclosing the drive shaft and cam. The drive housing includes a driven grip tube receiving bore having a longitudinal axis parallel to and offset from the longitudinal axis of the drive housing to facilitate ease of use by the operator. The removable driven grip tube includes a reciprocal needle bar having a cam follower at a proximal end and a needle attachment surface at a distal end.

The composite battery-integrated tattooing machine totally avoids a clip cord and the drag associated with it. The new machine comprises a base frame for removably holding a needle bar housing assembly, a tattoo needle assembly removably mounted to reciprocate within the needle bar housing, a reciprocating motion generator having at least one electromagnet and a make and break mechanism for effecting reciprocating motion of the tattoo needle assembly, a battery, a rheostat, and a switch for actuation of the reciprocating motion of the tattoo needle assembly. An important switch arrangement is radio operated; other switches are hand operated. Special subassemblies are provided for conversion of known professional tattooing machines into the new type having battery power integrated with the tattooing machine. Experts can now tattoo without the annoying drag of a clip cord.

The object of the invention is to ease of operation of the power impact tool. Such object is achieved by a representative power impact tool according to the invention including a motor, a tool bit, a trigger and a mode changing member. The trigger is manually operated by a user to control energization and non-energization of current to drive the motor. The motor is energized when the user operates the trigger to turn on and the energized state of the motor is maintained until the trigger is again operated in a same manner with the turning-on operation. According to the invention, once the trigger is depressed from the initial position to the operating position, a hammering operation can be performed by the striking movement of the tool bit without the need to lock the trigger in the operating position. Therefore, ease of operation of the hammer drill is enhanced.

A rechargeable fillet knife comprises a tubular handle defining an interior cavity having front and rear portions. A reciprocating motor is disposed in the front portion of the interior cavity with a pair of blades coupled to the motor. A rechargeable battery is disposed within the rear portion of the interior cavity and is selectably removable therefrom. The battery and motor are electrically coupled to a trigger such that the motor is energized upon a user depression of the trigger. A male connector is electrically coupled to the battery and is configured to selectively mate with a socket. The socket is electrically connected to a connector assembly configured for insertion into a vehicle power receptacle or to a connector assembly configured for insertion into a wall outlet so as to provide electrical power to the battery. The battery may also be removed and inserted into a recharging unit.