Abstract:
A tattoo gun improvement comprised of an adjustment means for the main spring of the tattoo gun that permits adjustment of the angle of the spring relative to the frame and therefore the spring tension against the needle depth adjuster. The means of adjustment facilitates quick and accurate tension setting on the spring while avoiding the need to bend the spring or alter the needle penetration setting adjustment. By avoiding bending the spring the spring life is extended as well as the precision that the spring tension may be adjusted. A precisely and properly adjusted spring can allow the tattoo gun to be used with less power that further can result in less unnecessary trauma to the skin.

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to tattoo guns, and more particularly, to tattoo gun spring tensioning. 
     2. Description of the Related Art 
     Several designs for tattoo guns have been designed in the past. None of them, however, includes a means to selectively tune the tension on the spring without bending the spring itself and without affecting the depth of the needle stroke. 
     Applicant believes that the closest reference corresponds to U.S. Pat. No. 4,159,659 issued to Nightingale on Jul. 3, 1979. However, it differs from the present invention because the present invention allows a user to adjust the tension on the spring without bending the spring or affecting the depth of the needle stroke. Nightingale does have some adjustability but only on the rear spring and not on the front spring as is critical in the present invention. 
     The Nightingale device, as in all known prior art, requires adjusting the bend in the spring to adjust tension which leads to imprecise results and metal fatigue which results in the spring losing its tune and ultimately spring failure. The Nightingale device also does not permit precise, consistent and long lasting tuning to the spring whereas the present invention allows a user of the device to easily and consistently properly tune the tension on the spring. 
     Other patents describing the closest subject matter provide for a number of more or less complicated features that fail to solve the problem in an efficient and economical way. None of these patents suggest the novel features of the present invention. 
     SUMMARY OF THE INVENTION 
     It is one of the main objects of the present invention to provide a tattoo gun that is easy to consistently tune the spring to a desired tension. 
     It is another important object of the present invention to provide a means to adjust the tattoo gun spring independently from the depth stop adjustment while also avoiding the need to bend the spring for adjustments. 
     It is another object of this invention to provide a device that retains the spring tension setting and improve the life span of the spring by avoiding metal fatigue failures by avoiding the necessity to bend the spring. 
     It is still another object of the present invention to provide a tattoo gun that can be operated on less power when the spring is properly tuned and not over-tuned thereby saving energy and increasing the safety of the device for the artist and the one receiving the tattoo. 
     It is an additional object of the device to allow a low tension tuning of the spring to be consistently achievable thereby allowing softer needle strokes which in turn reduce damage to the skin being tattooed and decreases healing time and less blood loss. 
     It is another object of the present invention to allow the tension on the spring to be adjusted without bending the spring to facilitate the device handling both shading needles and lining needles. 
     It is yet another object of this invention to provide such a device that is inexpensive to manufacture and maintain while retaining its effectiveness. 
     Further objects of the invention will be brought out in the following part of the specification, wherein detailed description is for the purpose of fully disclosing the invention without placing limitations thereon. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       With the above and other related objects in view, the invention consists in the details of construction and combination of parts as will be more fully understood from the following description, when read in conjunction with the accompanying drawings in which: 
         FIG. 1  represents an elevation view of the present invention. 
         FIG. 2  shows a perspective view of the prior art. 
         FIG. 3  illustrates an exploded perspective view of the present invention. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     Tattooing skin has been practiced through millennia. Generally, a colorant or ink is placed onto the skin and a needle is used to pierce the epidermis and dermis allowing the colorant to penetrate the skin where it remains. A completed tattoo is formed from thousands of dots each from an individual pierce of the needle. Since the electrical age tattoo guns have been available that rapidly reciprocate a needle to aid in producing a tattoo. 
     In most tattoo guns used today a needle is affixed to a flat springy piece of metal known as a spring. An electromagnet draws the spring down and then releases it in rapid succession to create a reciprocating action of the needle. The needle is pressed against the skin to create shallow perforations allowing the colorant to penetrate the skin thereby permanently coloring the skin. 
     Careful control of the reciprocating action of the needle is preferred for the best control of the results obtained by the tattoo gun. How firmly the spring presses against the depth adjuster affects the performance of the device by changing the tension on the spring therefore affecting how much action and play there is in the spring and the connected needle. For tattooing operations such as drawing outlines, the preferred tension on the spring relative to the depth adjuster is different than when shading or filling procedures are performed. 
     Until now the means to adjust the tension of the spring onto the depth stop adjuster has been to bend the spring to varying degrees. Bending the spring is imprecise at best and time consuming. Bending the metal spring also imparts metal fatigue on the spring which can cause it to fail or change springy-ness after prolonged use. 
     The present device includes an additional adjustment means to precisely and predictably adjust the tension on the spring against the depth stop adjuster without repeatedly bending the spring. This results in a finely tuned spring that is more controlled, uses less energy, produces less skin damage and lasts longer than any other tattoo gun known or available today. 
     Referring now to the drawings, where the present invention is generally referred to in  FIG. 1  with numeral  10 , it can be observed that it basically includes, inter alia, a frame  12 , a bar  14 , a point  16 , a spring  18 , an adjuster  20 , an arm  22 , a fastener  24 , a fastener  26 , spacers  28 , electromagnets  30 , a contact  32 , fastener  34 , guide  36 , fastener  38 , heel  40  and contacts  48 . 
     When the device is in use a needle (not shown) is fixed onto the point  16  and fed through the guide  36 . A needle tube (not shown) is often fit into guide  36  and held by fastener  34  to more accurately guide the needle and provide a means to hold the device. To reciprocate the needle an external power supply (not shown) rapidly cycles power on and off so that the electromagnets  30  turn on and off. When the electromagnets  30  are supplied power they attract bar  14  and pull against the spring  18  toward the contacts  48 . The power is then momentarily interrupted and the spring  18  returns to its position up against the adjuster  20  taking point  16  and necessarily the needle with it. The electromagnet  30  on/off cycle is repeated hundreds of times per minute causing the needle to reciprocate up and down through the guide  36 . 
     The frame  12  is generally provides the structure onto which the other elements of a tattoo gun are affixed. Integral to the frame  12  is the arm  22  that in the preferred embodiment of the device is immovable relative to the frame. The arm  22  supports the adjuster  20  that functions generally to adjust the stroke length that a tattoo needle (not depicted) has by limiting how far the bar  14  can move away from the electromagnets  30 . 
     The primary moving parts of the invention are the spring  18  and bar  14 . The spring  18  is affixed to the bar  14  by means of a fastener  24 . Said spring  18  is connected to the heel  40  by means of fastener  26 . Said fastener  24  or fastener  26  could be, for example, a screw, bolt or any other such means commonly available in the art to affix an object to another. 
     The heel  40  is adjustably connected to the frame  12  and secured relative to the frame  12  by means of fastener  38 . Fastener  38  is preferably able to be tightened and loosened by hand such as by means of a wing nut. Because the spring  18  is connected to the heel  40  the spring  18  may be adjusted relative to the position of the frame  12  by loosening fastener  38  and rotating the heel  40  relative to the frame  12 . Fastener  38  is then tightened to secure the angle of the spring  18  relative to the frame  12 . 
     When no current is supplied to the device through contact  32  the spring  18  is biased away from the contacts  48  on the electromagnets  30  and the spring  18  is limited by the position of the adjuster  20 . The circuit is completed by attaching a ground to anywhere on the frame other than the contact  32 . 
     Spacers  28  electrically insulate the electromagnets  30  from the frame  12 . Spacers  28  may optionally also provide a vibration dampening means if made of a pliable material such as a rubber so that when the bar  14  strikes the contacts  48  of the electromagnets  30  the impact force is absorbed by the spacers  28  and not transferred into the frame  12 . 
     It is key to the performance of the device how much force is applied onto the adjuster  20  by the spring  18  when no current is supplied to the device. When the device is being prepared for use typically fastener  38  is loosened and the spring  18  is held against the adjuster  20  with appropriate force and then fastener  38  is re-tightened. Prior art designs such as that depicted in  FIG. 2  require that spring  54  be bent against adjuster  64 . 
       FIG. 2  is an example of common tattoo guns in the prior art and is shown for comparative purposes to include, inter alia, a frame  50 , an arm  52  a spring  54 , a bar  56 , electromagnets  58 , fastener  60 , fastener  62  and an adjuster  64 . 
     The device in  FIG. 2  operates in some ways similar to the present invention as generally shown in  FIG. 1  in that said spring  54  is biased toward said adjuster  64  and when the electromagnets  58  are energized they attract bar  56 . When the electromagnets  58  are not energized the spring  54  pulls the bar  56  away from the electromagnets  58 . The cycle is repeated many times per minute and the needle reciprocates rapidly allowing the user to make many skin perforations in a shorter amount of time than otherwise possible. 
     A limitation with the prior art as shown in  FIG. 2  results from the fixed geometry of the frame  50 . The angle of the spring  54  relative to the frame  50  is permanently set when the frame  50  is forged. When the spring  54  is affixed to the frame  50  by means of fastener  62  the only way to change the relative angle is to bend the spring  54  which has inaccurate and inconsistent results which in turn reduces the accuracy of the device. The novel features of the present invention solves this inherent limitation in the prior state of the art. 
     Now referring to  FIG. 3  where the present invention is demonstrated in an exploded perspective view to provide more detail and further includes, inter alia, a yoke  42 , an eye  44 , a joint  46  and a joint  66 . When the device is in use fastener  38  (shown in  FIG. 1 ) passes through yoke  42  on the frame  12  and eye  44  on the heel  40 . When the fastener  38  is tightened down the joint  46  compresses and the yoke  42  pinches the eye  44  thereby preventing any unwanted movement of the heel  40  relative to the frame  12 . 
     To prepare the tattoo gun for use the user would typically loosen fastener  38  and rotate the spring  18  about the eye  44  and yoke  42  joint so that the spring  18  contacts adjuster  20 . The tension on the spring  18  is set by holding the spring  18  against the adjuster  20  to the desired tension and then tightening the fastener  38 . This is a much more precise and simple method than bending the spring  54  as would be required by the prior art shown in  FIG. 2 . 
     A similar joint  66  is also provided on the opposite end of the frame  12  that compresses under force applied by fastener  34  to hold a needle tube (not shown). The needle tube guides the needle and provides a safe and comfortable place to hold the tattoo gun while in use. 
     Arm  22  is shown more clearly in  FIG. 3  where it can be seen to be integral to the frame  12 . Arm  22 , in the preferred embodiment, should not interfere with the movement of the heel  40  and spring  18  when adjusting the device. Arm  22  is contemplated to be further include a decorative design that does not contribute to the inventive functionality of the device. For example, an alternative to the goose neck design shown in  FIG. 3  a lightning bolt or other non-functional design element could be included in the final design. 
     In a preferred embodiment of the invention is a tattoo gun comprising a frame having one or two electromagnets affixed thereto; a heel adjustably affixed to said frame; a spring affixed to said heel so that said spring is adjustable relative to said frame; said spring biased away from said electromagnets; said spring biased toward a depth adjuster; said spring disposed between said electromagnets and said depth adjuster. It can be further characterized in that a vibration dampening spacer is disposed between the electromagnetic coils and the frame. It can be further characterized in that said tattoo gun is battery powered. 
     Another embodiment of the invention is described as tattoo gun comprising a frame, a heel, a spring, an arm and a depth adjuster; said arm formed integral to said frame; said heel adjustably affixed to said frame; said spring affixed to said heel; said depth adjuster adjustably affixed to said arm; said spring biased toward said depth adjuster; where the strength of bias of said spring is adjustable by rotating said heel relative to said frame and where said heel is fixable relative to said frame; said spring being disposed between said depth adjuster and one or two electromagnetic means. It can be further characterized in that a vibration dampening spacer is disposed between the electromagnetic coils and the frame. It can be further characterized in that said tattoo gun is battery powered. 
     Another primary embodiment of the invention can be described as a direct current tattoo gun comprising one or two electromagnetic coils affixed to a frame; said frame having an arm terminating in an adjuster; a flat spring adjustably affixed on a first end to said frame; said flat spring being disposed between said electromagnetic coils and said adjuster; a magnetically attractable bar having a first end affixed to said spring and at a second end to a point suited for attachment to a tattoo needle; said spring biasing said bar away from said electromagnetic coils; said electromagnetic coils positioned to attract said bar; said spring being adjustable to impart more or less force onto said adjuster. It can be further characterized in that a vibration dampening spacer is disposed between the electromagnetic coils and the frame. It can be further characterized in that said tattoo gun is battery powered. 
     The foregoing description conveys the best understanding of the objectives and advantages of the present invention. Different embodiments may be made of the inventive concept of this invention. It is to be understood that all matter disclosed herein is to be interpreted merely as illustrative, and not in a limiting sense.