Abstract:
A manual ink applicator for use in screen printing which uses a squeegee that is mounted on a pair of pivoting links. The links in turn are mounted on a pair of shuttle blocks. The pivoting links raise the squeegee from the screen surface when the shuttle blocks make contact with the top and bottom ends of the screen frame or adjustable stops mounted to the sides of the screen frame, and the operator continues in the same direction as the squeegee was moving just prior to the blocks making said contact. The operator then changes the direction of movement of the squeegee. There is a handle and a brace attached to the shaft. The user places his or her arm through the brace and grasps the handle. By applying the force to the squeegee through the handle, brace and shaft, the force to the squeegee is substantially greater than if just applied to the squeegee by the user&#39;s hands. This minimizes user fatigue and allows a greater and more uniform force to be applied to the squeegee than by previous manual devices.

Description:
BACKGROUND OF THE INVENTION 
     This invention relates to manual hand tools and more particularly to manual ink applicators commonly used in screen printing. 
     Clothing such as T-shirts, sweatshirts and the like commonly have images and printing placed on the article by a process called screen printing. Generally the process is done manually or automatically on screen printing machines. In either the manual or automatic process there is a screen firmly held slightly above the article of clothing. A flood bar is placed in contact with the screen and passed over the screen, spreading ink over the screen surface. Next a print squeegee is moved across the surface of the screen and a downward pressure is applied, which forces printing ink through the screen and onto the material that is to receive the image. 
     The manual screen printing process has some advantages over the automatic printers. They are relatively inexpensive to purchase and operate. They are also energy and space efficient. The manual process is particularly well suited for small runs and test runs prior to setting up the automatic machines. 
     However, there are several problems that arise when using manual printing machines that are not present when using an automatic machine. First, the manual printing machines operate slowly. One reason is that the squeegee requires a substantial amount of pressure applied to it to force the ink through the screen. The operator must flood the ink consistently and then apply adequate pressure to print an article. In order to get the density, opacity or finish desired, and depending on the pressure applied, it may require multiple passes of the squeegee. Further many plastisol ink colors have a high tack level and require considerable force to transfer the ink cleanly through the mesh of the screen. Second, when applying high-density inks, the same problems as stated above are present and a sufficiently high and constant pressure is required for clean printing. A substantial force is required to be applied to the squeegee throughout the printing stroke. Most operators cannot withstand this effort for making multiple prints as fatigue sets in. The results of manual screen printing using a conventional squeegee are inconsistency and diminishing productivity. Furthermore, job related injuries such as carpal tunnel syndrome often result. 
     SUMMARY OF THE INVENTION 
     Applicant&#39;s invention provides a manual tool that applies the required force necessary to print with today&#39;s inks. The tool transfers the force from the user&#39;s arm and body to the squeegee instead of applying the force from the user&#39;s wrists and fingers to the squeegee. Thus, greater force can be applied to the squeegee and fatigue to the user&#39;s wrists, hands and fingers is minimized. 
     Applicant&#39;s device has a pair of opposed shuttle blocks positioned on either side of the screen printing apparatus. Each shuttle block has a pivoting bracket mounted on it. A squeegee is mounted between and to the pivoting brackets. There is a shaft having one end connected to the squeegee holder. Near the other end of the shaft is a brace through which the user places his or her arm. The user grasps a handle on the shaft so that when the user grasps the handle and the brace encompasses the user&#39;s arm, the shaft and the user&#39;s arm are aligned. The user applies a force to the squeegee through the handle and shaft for spreading the ink and for printing. In a first position, the pivoting bracket and squeegee assume an orientation to spread or flood the ink on the screen and in a second position in which the brackets are pivoted, the squeegee assumes an orientation for printing. The apparatus allows the user to apply greater forces with ease to the screen for printing, which minimizes fatigue and improves printing. 
     OBJECTS AND ADVANTAGES 
     Thus it is an object of the invention to provide a manual ink applicator that allows the user to apply greater forces to the squeegee than have previously been applied using the user&#39;s hand and fingers. 
     Another object is to provide a manual ink applicator that places the squeegee in a first orientation to spread or flood the ink across the screen when moved in a first direction and places the squeegee in a second orientation to print when moved in the opposite direction. Related to this object is the object of mounting the squeegee on a pivoting bracket arrangement that allows the squeegee to move from the first orientation to the second orientation by means of the pivoting bracket. 
     Still another object is the object of providing a manual ink applicator for screen printing in which the force from the user is transferred to the squeegee through the applicator without the user grasping the squeegee by the user&#39;s hands to apply the printing force. A related object is the object of providing a manual ink applicator in which the applicator has a handle that is grasped by the user and a brace that encompasses the user&#39;s arm to align the applicator with the user&#39;s arm. An advantage of this apparatus is to efficiently transfer the force from the user to the squeegee. 
     Yet another object is to provide a squeegee that operates as a flood bar in one direction and a pressure applying squeegee in the other direction and in which the squeegee is raised above the screen when changing directions so that it is raised up and passes over the ink when changing directions. 
     These and other objects and advantages will be apparent from reading the Description of the Drawings and Description of the Preferred Embodiment. 
    
    
     DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a left side elevation view of the manual ink applicator. 
     FIG. 2 is a left side elevation view of the manual ink applicator mid way position between the first and second operating positions. 
     FIG. 3 is a front elevation view of the pivot bracket. 
     FIG. 4 is a top plan view of the ink applicator handle and shafts with the squeegee and pivot brackets removed. 
     FIG. 5 is left side elevation view of the applicator shown in FIG.  4 . 
     FIG. 6 is a top view of the ink applicator showing the user&#39;s arm inserted through the adjustable strap and the operator&#39;s hand grasping the handle. 
     FIG. 7 is a self side elevation view of the ink applicator in three positions, the first position being the ink spreading or flooding position, the second position being an intermediate position, and the third position being the printing position. 
     FIG. 8 is a side elevation view of the shuttle block. 
     FIG. 9 is a top plan view of the shuttle block of FIG.  8 . 
     FIG. 10 is an end view of the shuttle block of FIG.  8 . 
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENT 
     Turning to FIG. 1 there is illustrated a manual ink applicator  10  of the present invention. There is at least one shaft, illustrated as a first shaft  12 , and additionally preferred a second shaft  14 . The shafts  12  and  14  are parallel to each other and are joined by a handle  16 . The shafts and handle may be joined together by conventional means, such as conventional fasteners or adhesives, or can be integrally molded together of plastic. The shafts  12  and  14  have proximal ends  18  and distal ends  20 . 
     Mounted to the distal ends  20  is a support member  22  or support bracket  22  that is generally L-shaped to aid in securely mounting it to the distal end  20 . Screws or other conventional fasteners  24  are used to attach one arm of the L-shaped support member  22  to the distal end  20  of the shafts  12  and  14 . A squeegee  26  of conventional design is attached to the other arm of the support bracket  22  by means of fasteners  28 , which pass through a support plate  30 . The squeegee  26  is made of flexible rubber-like material and is used to flood the ink over the screen when moved in a first direction and to print the image when the squeegee is moved in a second direction opposite the first direction. 
     At the proximal end  18  of the shafts  12  and  14  is an arm brace  32 . As shown, the brace  32  is an adjustable flexible strap that has one end passing through a slot  34  in the proximal end of the first shaft  12 . The other end of the flexible strap passes through a second slot  36  in the proximal end  18  of the second shaft  14  (FIG.  6 ). Using conventional means, the length of the strap can be adjusted to snugly accommodate the user&#39;s arm in a loop formed in the adjustable strap. The brace  32  can be made of other materials, both flexible and rigid. However, it is designed to snugly receive the user&#39;s arm when the user&#39;s hand grasps the handle  16  as seen in FIG.  6 . In this manner, the user&#39;s arm becomes aligned with, and connected by means of the arm brace  32  to, the shafts  12  and  14  when grasping the handle  16 . Furthermore, by adjusting the length of the strap, the angle of the squeegee with respect to the screen is changed. This changes the printing characteristics, which depend on the skill of the operator to achieve the desired printing results. 
     A screen is placed above the material or object on which the image is to be applied. As seen in FIG. 6, the screen has a screen frame  35  that borders the area in which the screen printing takes place. The frame  35  is securely held in place during the printing process. Generally the image area has a layer of ink applied over the area, which is called flooding. The squeegee  26  spreads the ink evenly over the image area by moving in a first direction over the image area and applying a light pressure to the screen, which is not sufficient to cause the screen to contact the material on which the image is to be applied. Then the squeegee is moved in a second direction, opposite the first direction and with a greater pressure, pushes the screen in contact with the material, and forces the ink through the screen onto the material where the image is printed. The printing cycle comprises both a flooding and printing stroke. In the preferred embodiment as seen in FIG. 6, the flooding takes place when the squeegee  26  is pulled toward the user which is in the direction of arrow A. The printing takes place when the squeegee is pushed away from the user in the direction of arrow B. However, the reverse directions can also be used for flooding and printing. The important point is that the printing takes place when the squeegee  26  applies sufficient pressure to the ink to force it through the screen and onto the image receiving surface. 
     As seen in FIG. 6, the ink applicator  10  has a first shuttle block or ski  38  positioned next to the frame  35 . Opposite the first shuttle block  38  is a second shuttle block or ski  40 . The construction of the shuttle blocks  38  and  40  is illustrated in FIGS. 8-10. The shuttle blocks  38  and  40  are preferably made of nylon or plastic and have a smooth bottom surface  42  that easily slides over the screen. There is an axial passageway  44  that extends through the shuttle block from one side to the other. There also is a longitudinal groove  46  that is cut from the top of the shuttle block  38  to below the axial passageway  44 . The longitudinal groove  46  extends from a forward end  47  to a trailing end  48  of the shuttle block  38 . The longitudinal groove  46  has a width “w” as seen in FIGS. 9 and 10. 
     A pivot bracket  50  is attached to each of the shuttle blocks  38 ,  40 . The construction of the pivot bracket is best illustrated in FIG.  3 . The pivot bracket  50  has a bottom end  52  and a top end  54 . There is a pivot shaft opening  56  passing through the bottom end  52  and a threaded rod opening  58  passing through the top end  54 . A fastener  60  such as a nut and bolt connects the bottom end  52  of the pivot bracket  50  to the shuttle blocks  38  and  40 . The fastener  60  passes through the axial passageway  44  and the pivot shaft opening  56 , thus connecting the pivot bracket  50  to its respective shuttle block  38  or  40 . The fastener  60  freely passes through the pivot shaft opening  56  so that the pivot bracket  50  easily pivots about the fastener  60 . The thickness of the pivot bracket  50  is slightly less than the width “w” of the longitudinal groove  46  so that the pivot bracket  50  can easily pivot about the fastener  60  and within the longitudinal groove  46 . 
     As most clearly seen in FIGS. 1 and 6, the support member  22  is connected to and between the opposed pivot brackets  50 . There is a tube or sleeve  61  that is welded or otherwise affixed to one of the arms of the support holder  22 . A threaded shaft or rod  62  passes through the tube  61  and has its opposed threaded rod ends passing through the threaded rod openings  58  in each of the pivot brackets  50 . The ends of the threaded rod  62  are attached to the pivot brackets  50  by an interior nut  64 , an end nut  66 , and optionally a washer  68 . The nuts  64  and  66  are tightened against the pivot bracket  50  sufficiently to keep the brackets  50  securely attached to the threaded rod  62 . In this manner as the brackets  50  rotate about fastener  60 , the threaded shaft  62  rotates within the tube  61  causing the support member  22  to move between the flooding and printing positions as will be more fully described below. In an alternate embodiment the threaded shaft  62  can be firmly connected to the arm of the support member  22  and the ends of the threaded shaft are connected to the brackets  50  in a manner that allows the ends to freely rotate within the threaded rod openings  58 . The nuts  64  and  66  are loosely secured on either side of the brackets  50  to insure free sliding of the bracket  50  between the nuts  64  and  66 . 
     In either embodiment the top end  54  of the pivot bracket  50  freely pivots about the threaded shaft  62 . The distance between the shuttle blocks  38  and  40  can be adjusted by means of the nuts  64  and  66  moving on the threaded shaft  62 . In this manner, the shuttle blocks  38  and  40  can be positioned and maintained adjacent to the sides of the frame  35 . The threaded rod  62  is secured to same arm of the support member  22  that the distal ends  20  of the first and second shafts  12 ,  14  are connected to. The threaded rod  62  can be attached in any of numerous conventional manners such as using fasteners or welding. The particular method of attachment is not critical, only that the relative mounting of the shaft  62  to the arm of the support holder  22  remains connected so that when the threaded shaft  62  moves, it moves in unison with the pivot bracket  50 . 
     In order to use the manual ink applicator  10 , the material to which the image is to be applied is securely held in place in the screen printing apparatus. The screen frame  35  is also secured above the material. The applicator  10  is set over the screen and the shuttle blocks  38  and  40  are positioned adjacent to the sides of the frame  35 . The user places his or her arm through the arm brace  32  and grasps the handle  16  with his or her hand. The user adjusts the arm brace  32  so that the desired angle of the squeegee is achieved and the user&#39;s arm is aligned with the shaft. The applicator  10  and the shuttle blocks  38  and  40  are pushed forward away from the user until they strike the forward edge of the frame  35 . The user verifies that the brackets  50  and the squeegee  26  are in a forward position, illustrated as Position  1  in FIG.  7 . In Position  1  the bracket  50  is pivoted forward about the fastener  60 . A bottom edge  70  of the squeegee  26  is disposed just above or slightly contacting the screen. Ink is applied to the screen in the conventional manner. The user pulls the handle  16  towards the user and applies slight pressure to the handle so that the bottom edge  70  of the squeegee remains above or in light contact with the screen. The ink is thus spread over the screen. 
     Once the squeegee  26  is drawn back as far as it can go, which is determined by the shuttle blocks  38  and  40  engaging the bottom edge of the frame  35  or stops (not illustrated) on the frames sides, the user pulls up on the handle  16  and pivots the pivot bracket about the fastener  60 . The ink applicator  10  moves into an intermediary position as illustrated in Position  2  in FIG.  7 . The bracket  50  is substantially upright and the top end  54  is pivoting about the threaded shaft  62 . The user continues moving the handle  16  and the shafts  14  and  16  toward the user to the position shown as Position  3 . The bottom edge  70  of the squeegee  26  is now resting upon the surface of the screen. 
     The user&#39;s wrist and forearm are now oriented in-line with the handle  16  and the first and second shafts  12  and  14 . The user applies a printing force from the upper body to the arm, forearm and wrist. The applied force is transferred through the brace  32  and the handle  16  to the first and second shafts  12  and  14 , to support member  22  and then to the squeegee  26 . At the same time the user pushes against the handle  16  in a forward direction away from the user, to move the ink applicator  10 . The printing force is easily and consistently applied from edge to edge across the squeegee  26 . The force is much greater than the force that the user can apply by just using his or her wrist and fingers against the squeegee  26 . The ink is forced through the screen onto the image receiving material. When the shuttle blocks  38  and  40  reach the forward or top of the frame  35 , or stops on the side of the frame, continued forward movement on the squeegee  26  and the handle  16  raises the handle  16  and causes it to pivot the pivot brackets  50  and the squeegee  26  from Position  3 , through Position  2 , and into Position  1 . The cycle is ready to be repeated as necessary to complete the printing process until the final image is printed onto the receiving medium. 
     When the squeegee  26  changes direction at the top end bottom of the frame  35 , the squeegee  26  is lifted up and out of contact with the screen. The squeegee is removed from contact with the ink on the screen surface and “jumps over” the ink so that the ink remains ahead of the squeegee regardless if the squeegee is in the flooding or printing stroke. 
     Utilizing the manual ink applicator  10  of the present invention allows the user to apply increased printing pressures over those manual systems in the past. The pressure is applied evenly and consistently across the squeegee  26 . User fatigue in the hands, wrist and arm is minimized or eliminated. All types of inks, even those which were difficult to apply with manual printing processes, can be applied with the applicator  10 . The materials used to manufacture the applicator  10  are inexpensive and long lasting. The applicator  10  is relatively simple to manufacture due to the relatively few number of moving parts. 
     Thus there has been provided a manual ink applicator for printing that fully satisfies the objects set forth above. While the invention has been described in conjunction with a specific embodiment, it is evident that many alternatives, modification and variations will be apparent to those skilled in the art in light of the foregoing description. Accordingly, it is intended to embrace all such alternatives, modification and variations as fall within the spirit and scope of the appended claims.