Abstract:
The invention relates to a deburring tool with a quick change knife, which is formed by at least two parts, namely a guide sleeve having a larger diameter and a center bore, and a base body that can be inserted in the center bore in an axial direction. The base body can be secured in the center bore. A knife groove is arranged on the base body that can receive the knife to be secured, forming a pivot support in the base body. Due to this special support, the knife can be easily exchanged even when the deburring diameters are small, for example, less than 4 mm, while still being able to absorb large deburring forces.

Description:
BACKGROUND OF THE INVENTION  
       [0001]     The invention is directed to a deburring tool with a quick change knife, made off at least two releasably connectable parts.  
         [0002]     The company Cogsdill supplies conventional tools that have an approximately cylindrical guide sleeve with a transverse slit extending over the entire length of the guide sleeve, with a fastening screw extending through the transverse slit at a predetermined location.  
         [0003]     The deburring knife to be inserted into the transverse slit has a forward cutter portion, followed by a neck with a reduced diameter, which transitions into a guide member with a greater diameter.  
         [0004]     This conventional knife is held in the guide sleeve by an approximately keyhole-shaped opening disposed in the guide member with the greater diameter, and a rotatable, key-shaped pin that can be inserted in the opening.  
         [0005]     In the open position, the knife is therefore inserted with the wider guide member into the longitudinal slit in the guide sleeve, wherein the fastening pin is rotated so that it can extend through the slit in the guide member of the knife which is open on one end. When the fastening pin is rotated, its greater cross-section engages with the keyhole-shaped opening in the knife, thereby holding the knife firmly in the knife holder.  
         [0006]     However, the knife can still cant in the knife holder, and in order to prevent canting, a projection, which cooperates with a corresponding adjustment screw, is formed on the rear free end of the conventional knife, which prevents canting of the knife in the guide sleeve.  
         [0007]     A deburring tool of this type with a quick change knife has proven useful, although the manufacture of the knife is relatively complex. The knife must also have a well-defined keyhole-shaped opening in the larger diameter guide portion, which is also difficult to produce.  
         [0008]     Such type of knife holder has proven to be impossible to manufacture, in particular for small deburring tools, which are used, for example, to debur hole with diameters smaller than 4 mm. Accordingly, for this application the conventional knife must be rigidly attached directly in the guide sleeve, for example by soldering or gluing. The knife could then no longer be exchanged.  
         [0009]     It is therefore an object of the invention to modify a deburring tool with a quick change knife, so that the knife can be exchanged easily and reliably even with small deburring diameters.  
       BRIEF SUMMARY OF THE INVENTION  
       [0010]     The present invention related to a deburring tool with quick change knife, made of at least two releasably connectable parts, wherein the deburring tool has a guide sleeve with at least one receiving opening, into which a base body with a knife groove and a knife is disposed, can be inserted, and wherein the guide sleeve, the base body and the knife can be directly or indirectly connected with each other for repeated release in such a way that in the operating position of the knife at least one cutting portion of the knife protrudes from the guide sleeve.  
         [0011]     More particularly, the deburring tool of the invention has at least two parts, made of a larger diameter guide sleeve with a center bore, wherein a base body can be inserted in the center bore in an axial direction, and wherein the base body can be secured in the center bore. In addition, a knife groove is arranged on the base body which receives the knife to be secured and forms a pivoting support in the base body.  
         [0012]     According to the aforedescribed technical teachings, a pivoting support that holds the knife is advantageously disposed between the knife and the base body, which facilitates an exchange of the knife. The knife can only be exchanged when the base body is pulled out of the center bore of the guide sleeve. However, as soon as the base body is inserted into the center bore of the guide sleeve, the knife that is inserted in the base body automatically centers of the corresponding stop faces of the center bore, so that it is securely attached to prevent displacement and rotation.  
         [0013]     According to the technical teachings, advantageously very small deburring tools suitable to debur holes with diameters of less than 4 mm can now also be easily exchanged, because such deburring tools can be easily manufactured in miniaturized form. The knifes can be easily held in the base body and the guide sleeve using the aforedescribed pivoting attachment. The knife is thereby particularly securely attached and is able to transfer large loads, because the pivoting support of the knife on the base body that is initially provided for assembling the knife becomes ineffective, when the base body is inserted and secured in the guide sleeve. The knife is then firmly secured in the center bore of the guide sleeve and can no longer be easily pulled out.  
         [0014]     Although the guide sleeve can be made of any suitable material, a preferred material is high-tensile steel. However, other materials, such as plastic, aluminum or a composite material can also be used. It is only significant to provide an accurately sized center bore in the guide sleeve in which the base body, which will be described below in more detail, can be inserted with as little play as possible.  
         [0015]     Preferably, the center bore is formed so as to extend throughout the guide sleeve, i.e., the center bore, penetrates the entire guide sleeve.  
         [0016]     In another embodiment of the invention, the center bore can also be formed as a blind hole which does not extend through the rear end face of the guide sleeve.  
         [0017]     Nevertheless, a center bore is arranged in the guide sleeve, with the base body that can be inserted into the center bore also formed as a cylinder, so that the two round elements formfittingly engage in the radial direction with as little play as possible.  
         [0018]     However, the invention is not limited to this embodiment, and an elliptical bore or a bore with a different profile can be provided instead of the round center bore. In this case, the portion of the guide member to be inserted into the bore can be adapted to the profile of the bore in the guide sleeve, so that both parts can again be pushed into each other with the proper orientation, with a form fit in the radial direction, and with as little play as possible.  
         [0019]     Providing the two parts with a particular profile has the advantage that the two parts can only be inserted into each other with a particular rotation position.  
         [0020]     The center bore also need not be arranged in the center of the guide sleeve, but can be offset from the center relative to the longitudinal axis of the guide sleeve. This eccentric arrangement of the receiving bore has the advantage that different base bodies can be interchangeably inserted into the receiving bore, i.e., different base bodies with different knifes can be interchangeably inserted into the guide sleeve. 
     
    
     BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS  
       [0021]     The invention will be described hereinafter in more detail with reference to the drawings that depict several different embodiments. Additional features, applications and advantages of the invention are illustrated in the drawings and in the description of the drawings.  
         [0022]     It is shown in:  
         [0023]      FIG. 1 a  cross-section of a first embodiment of the deburring tool in an assembled state;  
         [0024]      FIG. 2 a  cross-section through the embodiment of  FIG. 1  with the knife holder and the knife pulled out;  
         [0025]      FIG. 3 a  perspective view of the deburring tool of  FIG. 1 ;  
         [0026]      FIG. 4 a  perspective view of the deburring tool of  FIG. 2 ; and  
         [0027]      FIG. 5 a  second embodiment which is modified compared to the first embodiment of  FIGS. 1-4 . 
     
    
     DETAILED DESCRIPTION OF THE INVENTION  
       [0028]     In the first embodiment according to FIGS.  1  to  4 , a cylindrical guide sleeve  1  is provided which has a center through bore  5 . The center bore  5  is located at the rear end and penetrated by a cross hole  2 , in which a pin  6  is inserted. In addition, the front region includes a threaded cross bore  3 , in which a flat head screw  4  is inserted.  
         [0029]     The front end of the guide sleeve  1  is formed by an inclined, stepped shoulder  8  which is formed in one piece and of the same material as the guide sleeve  1 . The stepped shoulder has a cross-section with a smaller diameter.  
         [0030]     A base body  7  that can be displaced and secured in the axial direction is positioned in the center bore  5 . The base body  7  is essentially made of a guide member  9  with a greater diameter, with an axial knife groove  12  extending lengthwise through the guide member  9 . A knife holder  10 , formed as one piece with the guide member  9  and made of the same material as the guide member  9 , is located following the guide member  9 , whereby the knife groove  12  also extends through the knife holder  10 . In other words, the knife groove  12  extends through the guide member  9  and the knife holder  10  and terminates before a holder tip  21  which stabilizes the entire knife holder  10  and prevents the knife groove  12  from being spread apart by the forces exerted on the knife holder  10 .  
         [0031]     It is important that a knife  14  is pivotally supported in the knife groove  12 , with a pivoting bearing formed by an associated transverse pin  19 .  
         [0032]     The transverse pin  19  extends through a corresponding bore  20  in the guide member  9 , where it is anchored. The transverse pin  19  also extends through an approximately V-shaped groove  16  in the knife  14 , with the groove width expanding toward the outside.  
         [0033]     The knife  14  consists essentially of a wider guide portion  15 , followed by a knife neck  17  which is made in one piece and of the same material as the guide portion  15 , with the cutter portion  18  with the cutting edges arranged on the front free end of the knife neck  17 .  
         [0034]     The knife neck  17  is springy, so that the spring action of the knife neck  17  causes the cutter portion  18  to contact a bore (not shown in detail), with the cutter portion  18  deburring the edge of the bore by a rotary motion.  
         [0035]     The knife  14  can be exchanged by at least partially pulling the base body  7  out of the guide sleeve  1 , as shown in  FIGS. 2 and 4 . Before the knife  14  can be removed, the flat head screw  4  is loosened, which then no longer engages in the circumferential annular groove  11  disposed in the guide member  9  of the base body  7 . The entire base body  7  can then be pulled out at least partially towards the front, as shown in  FIGS. 2 and 4 .  
         [0036]     The guide member  9  can be held in the center bore  5  of the guide sleeve  1  by inserting the base body  7  partially in the center bore  5 , as shown in  FIG. 1 , so that the front portion of the knife holder  10  with the smaller diameter protrudes axially from the center bore  5 , resulting in the installation position depicted in  FIGS. 1 and 3 .  
         [0037]     It is important that the width of the guide portion  15  of the knife  14  corresponds exactly to the interior width of the center bore  5 , so that the stop faces  22  formed on the guide portion  15  of the knife  14  formfiftingly contact the inside wall of the center bore  5  in the guide sleeve  1 . This simple holding mechanism fully prevents canting and displacement of the knife  14 .  
         [0038]     This represents an essential advantage over the state of the art, since conventional knifes required an additional stop and a fastening screw to eliminate canting of the knife.  
         [0039]     With the solution according to the invention, it is sufficient to insert the knife  14  in the center bore  5  of the guide sleeve, wherein the knife  14  is pivotally supported in the knife holder  10 . The pivoting support is deactivated in the installation position depicted in FIGS.  1  in  3 , and is only effective when the knife is to be exchanged, as depicted in  FIGS. 2 and 4 .  
         [0040]     The diagram in  FIGS. 2 and 4  shows that the knife  14  can be easily exchanged because the knife  14  can easily drop out when the base body  7  is pulled out of the guide sleeve  1 , assisted by the conically widening groove  16 .  
         [0041]     The dimensions of the unobstructed width at the bottom of the groove  16  are selected so that the transverse pin  19  has a form fit without play. The knife  14  can then no longer move in the axial direction in the region of the groove  16 .  
         [0042]     When the base body  7  is installed in the guide sleeve  1 , the threaded portion of the flat head screw  4  engages formfittingly in the circumferential annular groove  11 , thereby securely fastening the base body  7  in the guide sleeve  1 .  
         [0043]     Because the annular groove  11  extends circumferentially, it is not necessary to maintain an accurate rotation position between the base body  7  and the guide sleeve  1 .  
         [0044]     However, the rotation position between the base body  7  and the guide sleeve  1  should be well defined for certain applications. To accomplish this, as indicated in  FIG. 2 , the rear end of the guide member  9  in the base body  7  can have a transverse groove  23 , with the transverse groove at least partially enveloping the pin  6 , thereby uniquely defining the rotation position (rotation lock).  
         [0045]     In addition, the engagement between the pin  6  and the transverse groove  23  can also accurately define the insertion depth. When the base body  7  protrudes from the guide sleeve  1 , the user can readily recognize when the transverse groove  23  does not envelop the pin  6 , which would indicate a wrong position lock. The flat head screw  4  can then also not be screwed into the annular groove  11 .  
         [0046]      FIG. 5  shows another embodiment of a rotation lock between the base body  7  and the guide sleeve  1 . In this embodiment, a longitudinal groove  13  extends along the guide sleeve  1 , in which a headless screw or a pan head screw  4   a  can engage. By inserting the headless screw or a pan head screw  4   a  in the longitudinal groove  13 , the base body  7  is securely locked in the guide sleeve  1  against rotation and displacement in the axial direction. As soon as the headless screw  4   a  is loosened, its threaded side disengages from the longitudinal groove  13 , and the base body  7  can now be pulled out of the guide sleeve  1  in the direction of arrow  24 .  
         [0047]     In the operating position, the cutter portion  18  can be springily pivoted in the directions of arrow  25  against the spring force of the knife neck  17 . The cutting edges on the cutter portion  18  then contact the edge of the hole that is to be deburred and debur the hole with a rotary motion.  
         [0048]     In other words, the cutter portion  17  can be springily pivoted in the directions of the arrow  25 .  
         [0049]     The aforementioned pivoting support of the knife  14  with a simple groove  16  and a transverse pin  19  results in a particularly simple construction of the knife  14 . No additional projections, shoulders or supports and the like are required to prevent the knife  14  from canting. Canting is prevented by pulling the base body  17  into the center bore  5  of the guide sleeve  1 .  
         [0050]     Since the knife groove  12  is formed continuously, the knife  14  can advantageously be inserted into the knife groove  12  for support either from below, or—in an orientation rotated by 180°—from above, where it is then securely held.