One of the “must have” tools nowadays in your car and at your home is the cordless impact wrench. It is unlike the usual impact wrench that has cord and is powered either by hydraulic or compressed air. This wrench runs on electricity and rechargeable battery. This makes this tool easy and handy to stash in your car glove compartment for ready use when needed. Moreover, it makes any work of assembling and disassembling easy and effortless.
The cordless impact wrench utilizes the same mechanism as those of the common impact tools. Yet, let me give you a little overview of how it and the common impact wrench work.
It is of the most useful tools in industries such as automotive repair, product assembly projects, heavy equipment maintenance, and many other operations. The impact wrench has become so vital in the said industries that it was given many nicknames such as—impactor, air gun, air wrench, rattle gun, windy gun, and torque gun. Impact wrench is definitely a power tool, designed to convey a very high output of torque, which an ordinary human hand cannot readily deliver. This ability to convey the required torque is done by storing energy in the form of a rotating mass; then suddenly unleashing this stored energy to the carefully designed output shaft.
The recent innovation of the impact wrench is the cordless option. It is designed for comfort and flexibility; without the cord, the user is readily afforded more agility and flexibility. For this reason, the cordless impact wrench, which can be readily charged, always comes in handy for small kind of assembling and disassembling works.
Power Source of common impact Wrenches
The power source of an impact wrench usually comes from compressed air. In some cases, electric and hydraulic powers are also used to create the necessary torque. Recently, however, the cordless electric devices are fast becoming popular among users.
In product assembly lines, the commonly used tool is the pulse tool considering the fact that it gives a mitigated torque and produces minimal noise levels. Likewise, these pulse tools utilize an oil medium to convey kinetic energy coming from the hammer to the anvil. This oil medium reduces the impulse force, giving it a smoother impulse with less torque in relation to weight ratio. Moreover, it makes possible the design of a shut off mechanism, which could readily shut off the tool after achieving the exact torque. However, these tools—with built-in shut off mechanism—are fast losing popularity, nowadays, because of the usual high mean shift it produces. Additionally, these impact wrenches come in different standard wrench drive sizes. These sizes range from 1/4″ drive tools to 3.5″ (designed for larger construction). The 3.4” comes only in pistol grip design.
Controlling the amount of torque
In technical parlance, the impact force of an impact wrench is very short when hammering. For this reason, it is difficult to readily measure the actual effective force at hand. There is also difficulty in figuring out the output of an impact force if the output is quite springy. This is because in springy output, the impulse will naturally be absorbed, and no substantial torque will be felt and applied. Thus, even a very experienced operator usually finds it hard to figure out the right amount of impulse force to apply. The good thing is that some have built-in control system for regulating torque. This built-in control system readily shuts down the tool when the amount of torque applied has reached the necessary amount of impulse force. Impact wrenches like these are usually used in product assembly lines. However, when very precise torque is required, it is often only used to fit the fastener; a torque wrench would then be used for the actual tightening.
The Hammer Mechanism of an Impact Wrench
The usual design of a cordless impact wrench mimics the movement and impact of the common hammer. The hammer inside has to spin freely to impact the anvil. Likewise, it has to release it immediately and make it spin freely once again. This mechanism is commonly referred to as the hammer mechanism. Many designs have tried to mimic and achieve this task with many drawbacks. If you take a look inside the cordless wrench, you will see how this hammer mechanism works and how the hammer is allowed to slide and then rotate easily on a shaft, while a spring holds the hammer downward. The channeling of energy creates the torque.
There are many designs for the hammer mechanism and most of these designs have the usual goal of letting the hammer free itself from the anvil. However, it depends on how you are going to use the impact wrench that makes it relatively effective.
Choosing the right Cordless Impact Wrench
Cordless impact wrenches, as mentioned earlier, are the latest innovations in the development of it. It allows more flexibility without the usual hassle of having to tag along with you a long cord while doing your work. Most of these wrenches are not really necessary to our daily works at home. Yet, you may ask: “Why do we need to avail ourselves of one if it is not really necessary?” The reason is—the cordless impact wrench facilitates our work at home and even outside of our house. It makes work easy and that spells the difference between using your raw strength and using the augmented strength of a one.
Moreover, in choosing the right cordless wrench, you have to look into the capacity of the wrench you are about to buy. You also have to know how many times the hammer hits the anvil per minute. Likewise, you must also know how hard the hammer hits. Additionally, you have to look into the kind of battery being used for the unit to make it sure that it will always have optimum performance. There are a number of battery choices: some of which are made of nickel-cadmium; while others are made of more expensive stuffs such as the expensive lithium-ion. All these technical factors are usually specified by the manufacturer of the cordless impact wrench.
Lastly, before buying one, make a comparative study of the technical aspects of the different brands. Some of the leading brands of cordless impact wrench are Snap-on, Craftsman, Kobalt, and Harbor Freight.