Patent Publication Number: US-2023134382-A1

Title: Bodywork dent repair tool with pdr method

Description:
This application is a nonprovisional application which claims a priority of Polish patent application no.: P.439363, filed on Oct. 29, 2021, the content of which is hereby incorporated by reference. 
     The subject of the invention is a tool for repairing dents in a car body using the PDR method (Paintless Dent Removal), applicable in the automotive industry, especially in bodyshops. 
     PDR is a popular method of repairing dents without painting. It consists in pushing out or pulling out small dents. Removing dents without painting is made with the use of a special, professional glue. By using this glue and the picks (hooks) the dents are “pulled out”. This way is used in the case of elements that are difficult to access, because it does not require the disassembly of individual car parts, including the removal of roof lining, when a dent was formed on the roof by hail. The second method on repairing dents without painting is pushing them out. This PDR technique works best when the dent cannot be reached from the inside, especially in the case of the tailgate (trunk lid), doors or fenders. The dent is pushed out with the use of specialized tools, which, due to the type of damage, may differ in the length, thickness and shape of tags. Their selection depends on both the shape of a dent and its location. 
     Some PDR tools have replaceable screw-in tags (steel or made of plastic) in the form of balls, cones or tips. Depending on the type, there are devices with different shapes of the fin and flag. Some models are equipped with a regulated, adjustable handle, which facilitates the implementation of repairs. When working on body parts without reinforcements, tools are used which work on the principle of a lever and require appropriate support in the form a suspended ring or chain. To remove dents in reinforcement places are used fin tools, inserted between the reinforcement and the outer sheathing of a vehicle. In this case, it is possible to repair parts that do not have technological holes allowing the insertion of a tool. Fins give the ability to go under the reinforcement directly at the dent and work on the principle of twisting. There are known PDR door tools which enable to remove dents in an outer door sheathing, front and rear fenders. They are inserted between the window reinforced with a plastic cover and the bodywork sheathing tilted with a wedge and also work by twisting. 
     Technologically, we also know PDR tools: with a replaceable or fixed tip, with a length from approx. 13 cm to 187 cm, with a cross-sectional diameter of approx. 0.3 cm to 4 cm, from no bends (folds) up to 3 bends, with an exchangeable or fixed handle, with a curved, conical or flat tip. 
     From current state of technology, we also know the dent removal tool according to the invention U.S. Pat. No. 9,868,143B2, which includes a removable end tip, conduit assembly and a handle. The conduit assembly includes many conduit segments of varying lengths that are detachable and replaceable. The length of the conduit assembly can be adjusted by joining one or more different lengths of conduit together. Depending on the type of dent to be repaired, one or more different types of tips may be attached to the conduit assembly. One type of head includes a T-bar with two ends, each end configured for attachment to one of a number of different types of tips. 
     The American patent description US2005252271A1 discloses a toolkit for the PDR process designed to remove a certain class of dents in panels of a car body that is modified to have removable handles (grips) with different positions relative to the working end of the tool. In this way, it is allowed for the modified toolkit to consist of a much smaller number of individual tools. 
     Tools for PDR processes with interchangeable handles and adjustable for tips with a diameter of more than 0.6 cm are also known in the state of technology. 
     The solutions known in the state of technology have an exchangeable and adjustable handle only for tips with a cross-sectional diameter from 0.8 cm upwards, which results from the used technology of metalworking processes for the production of thin PDR tool tips in the form of hooks and other shapes with a cross-sectional diameter of 0.3 cm to 0.7 cm, and also from the fact that any thermal interference in these small sections causes changes in the parameters of steel, and hence the deformation of the tool tips, what is a significant inconvenience during PDR repairs. In the state of technology, the tools with thinner sections have fixed handles that extend tips and bend in the form of a handle, often coated with various types of resins and plastics. 
     There are also metal handles used, and therefore they are slippery to the touch, which is an inconvenience in case of their use during PDR repairs. These handles are too short at the point of gripping what translates into the need for more force by an operator of the tool when using longer tips and balancing through it with the whole body. In addition, the tip fits very shallowly into the nipple of the handle, which often leads to the breaking of a nipple after using the tool for some time. 
     The invention overcomes the above-mentioned disadvantages. The purpose of the invention was to construct a universal tool for PDR repairs by developing such a handle and fixing the tips in the handle to—regardless of the tool tip diameter and shape used by an operator—operate it by one, universal and adjustable handle. Moreover, the specificity of the invention lies in the fact that, as a result of the use of those already known PDR tool manufacturing processes, the tool maintains PDR parameters desired by an operator such as malleability, resilience, flexibility and durability necessary for this type of repairs. What is more, the solution according to the invention makes it possible to maintain the properties spring steel used to make its tips and maintain the desired parameters for the tool during operation. The use of the invention also allows to limit the PDR toolkit by using one universal and adjustable handle. 
     The essence of the invention is a tool for repairing dents in the car body using the PDR method, containing at least an exchangeable working oval, conical or flat tip, octagonal nipple and handle, characterized by the fact that it is made of an interchangeable handle, especially for tips with a diameter of 0.3 cm to 0.7 cm, and a replaceable working tip, permanently joined with the sleeve (tube) and nipple, whereas the tip being knurled at the base of the tip at the length of 1 cm, and at the end of the tip base there is a sleeve (tube) with a hole drilled inside out with a diameter corresponding to the diameter of the tip, clamped with a punch on the base of the tip, at the same time, the tip with the sleeve clamped on it is pressed into the octagonal nipple for a length of 1 cm and welded with a thin weld, and the handle is equipped with an octagonal slot in which a nipple latch is mounted detachably by means of a spring ball. 
     Preferably, the tip is made of a non-weldable alloy. 
     Preferably, the sleeve (tube) is made of a soft weldable alloy. 
     Preferably, the spring ball is made of a steel spring increased by force D=M06, L=14. 
     Preferably, the tip with a cross-sectional diameter of 0.3 cm and 0.4 cm is knurled by rollers with a stroke of 1.2 mm. 
     Preferably, the tip with a cross-sectional diameter of 0.5 cm, 0.6 cm and 0.7 cm is knurled by rollers with a stroke of 1.6 mm. 
     Preferably, the tip, sleeve and nipple are tempered martensitically and then oxidised in a chemical bath or technically chrome-plated. 
     Preferably, the longitudinal handle is connected separately to the nipple by means of a spring ball screwed in the slot perpendicularly to the guiding of a working tip. 
     Preferably, the transverse handle is connected separately to the nipple by means of a spring ball screwed in the slot mounted transversely to the surface of the tool grip, however, a bolt made of small diameter wire is placed in the spring ball parallel to the axis of the handle. 
     Preferably, the handle is equipped with an octagonal slot mounted at the end the handle at right angles to the tool surface grip and transversely to the length of the handle. 
     Preferably, the handle is provided with an octagonal slot which is mounted at bored and milled head screwed in the handle from the face transversely to the length of the handle, using a threaded screw with a drilled and threaded hole under the snap-on locking spring ball. 
     In an example of the invention, a car body dent repair tool with the PDR method includes an exchangeable working tip ( 1 ), round, conical or flat, octagonal nipple ( 2 ) and handle ( 3 ), as well as replaceable handle ( 3 ), especially for the tips ( 3 ) with a cross-sectional diameter of 0.3 cm to 0.7 cm. The replaceable working tip ( 1 ) is permanently connected with the sleeve (tube) ( 4 ) and the nipple ( 2 ), whereas the tip ( 1 ) is knurled from the base of the tip ( 6 ) at a length of 1 cm, and at the end of the base of the tip ( 6 ) there is a sleeve ( 4 ) with a hole drilled inside out with a diameter corresponding to that of the tip ( 1 ), which is clamped with a punch ( 7 ) at the base of the tip ( 6 ). At the same time, the tip ( 1 ) with a sleeve clamped on it ( 4 ) is pressed into the octagonal nipple ( 2 ) by a length of 1 cm and welded to it with a thin welding ( 14 ). Moreover, the handle ( 3 ) is equipped with an octagonal slot ( 8 ) in which a snap nipple ( 2 ) is detachably fastened with a spring ball ( 9 ). 
     The tip ( 1 ) is made of a non-weldable alloy. The sleeve ( 4 ) is made of soft weldable alloy. The spring ball ( 9 ) is made of steel increased spring with the force D=M06, L=14. 
     Moreover, the tip ( 1 ) with a diameter of 0.3 cm and 0.4 cm is knurled by steel rollers with a stroke of 1.2 mm, and the tip ( 1 ) with a cross-sectional diameter of 0.5 cm, 0.6 cm and 0.7 cm knurled with rollers with a stroke of 1.6 mm. 
     In this example, the tip ( 1 ), sleeve ( 4 ) and nipple ( 2 ) are hardened martensitically and then oxidized in a chemical bath or technically chrome-plated. 
     Moreover, in this example, a combined handle ( 3 ) longitudinal ( 15 ) is used, separately connected with a nipple ( 3 ) by means of a spring ball ( 9 ) screwed in the slot ( 8 ) perpendicular to the guiding of a working tip. 
     In other cases of the invention creation, other types of handle have been used ( 3 ). 
     The transverse handle ( 3 ) ( 16 ) is separately connected to the nipple ( 2 ) by means of a spring ball ( 9 ) screwed in the slot ( 8 ) mounted transversely to the surface of the tool grip, whereas a bolt made of small diameter wire is placed in the spring ball parallel to the axis of the handle. 
     Another example depicts a handle ( 3 ), “large” ( 17 ) provided with octagonal slot ( 8 ) mounted at the end of the handle ( 3 ) at right angles to the surface of the tool grip and transversely to the length of the handle ( 3 ). 
     In another example, the “handle ( 3 ), small” ( 18 ) is equipped with an octagonal slot ( 8 ), which is mounted in a turned and milled head ( 11 ) screwed into the handle ( 3 ) from the front side transversely to the length of the handle ( 3 ), using a threaded screw ( 12 ) with a drilled and threaded hole ( 13 ) for a locking snap-on spring ball ( 9 ). 
     Depending on the application, the examples of the invention may vary as for the shape, length and diameter of the section of the tip ( 1 ), shape and size of the handle ( 3 ). 
    
    
     
       The subject of the invention in its exemplary embodiments is shown in the drawing, whereas: 
         FIG.  1    shows a front rectangular view of the tool; 
         FIG.  2    shows a front view of the tool without handle with the tip separated ( 1 ), sleeve ( 4 ) and nipple ( 2 ); 
         FIG.  3    shows the cross-sections and  45 -degree views of the sleeve ( 4 ) of different diameters from 0.4 cm to 0.7 cm; 
         FIG.  4    shows a cross-section of the nipple ( 2 ); 
         FIG.  5    shows a view of the handle ( 3 ) at an angle of 45 degrees; 
         FIG.  6    shows a front perpendicular view of the longitudinal handle ( 3 ); 
         FIG.  7    shows a front view of the transverse handle ( 3 ); 
         FIG.  8    shows a front view of the “big” handle ( 3 ) ( 17 ); 
         FIG.  9    shows a side view of the “small” handle ( 3 ); 
         FIG.  10    shows a front view of a turned and milled head ( 11 ) metal to the “small” handle ( 3 ) ( 18 ), with a threaded welded screw ( 12 ) in order to screw in the head into the handle body; with drilled and threaded hole ( 13 ) under the snap-on locking ball ( 9 ). 
     
    
    
     The invention will find its industrial application in the automotive industry, especially in bodyshops.