Abstract:
A power tool system has a power tool, a replaceable rechargeable battery unit for the power tool, and at least one coupling unit for charging the battery unit while being replaceably connected to the power tool; also a replaceable rechargeable battery unit for a power tool, a charger for charging a replaceable rechargeable battery unit for a power tool, and a power tool with a replaceable rechargeable battery unit are provided.

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     This application is a Continuation Application of U.S. application Ser. No. 10/562,667 filed on Dec. 28, 2005 U.S. Pat. No. 7,456,609. This application therefore claims the benefit of priority of U.S. patent application Ser. No. 10/562,667 under 35 U.S.C. 119(e) and the subject matter of U.S. patent application Ser. No. 10/562,667 is explicitly incorporated herein by reference thereto. 
    
    
     The invention described and claimed hereinbelow is also described in German Patent Application DE 10 2004 040 922.6 filed on Aug. 24, 2004. This German Patent Application, whose subject matter is incorporated here by reference, provides the basis for a claim of priority of invention under 35 U.S.C. 119(a)-(d). 
     BACKGROUND OF THE INVENTION 
     The invention is based in particular on a replaceable rechargeable battery unit for a power tool which is provided for detachable connection to a power tool. For being charged, the replaceable rechargeable battery unit has a coupling unit, formed by charge contacts. The coupling unit is located on a part of the replaceable rechargeable battery unit that can be inserted into a receptacle region of a power tool. Once the replaceable rechargeable battery unit has been inserted into the receptacle region of the power tool, the coupling unit is covered by the housing of the power tool. For charging the replaceable rechargeable battery unit, this unit must be removed from the receptacle region of the power tool and inserted by the insertable part into a charger. 
     SUMMARY OF THE INVENTION 
     The invention is based in particular on a replaceable rechargeable battery unit for a power tool having a coupling unit for charging the battery unit. 
     It is proposed that the coupling unit is provided for charging the replaceable rechargeable battery unit in the mounted state on a power tool. The term “provided” should be understood in this connection to mean in particular designed and/or equipped. 
     With the embodiments according to the invention, the replaceable rechargeable battery unit can be conveniently charged between uses without having to be removed from the power tool. Nevertheless, in continuous operation of the power tool, it can easily be replaced with another, already-charged replaceable rechargeable battery unit. The embodiment according to the invention is fundamentally applicable to all replaceable rechargeable battery units that appear useful to one skilled in the art, but especially advantageously to replaceable rechargeable battery units whose charging capacity is at least essentially independent of whether the replaceable rechargeable battery unit before being charged was always completely emptied and thus has no so-called “memory effect”, as is the case for instance with replaceable rechargeable battery units based on lithium-ion technology, and so forth. 
     For this purpose, the coupling unit may either be located in a region which is directly accessible or contactable even when the replaceable rechargeable battery unit is in the mounted state on the power tool, and/or it may be located in a covered region and designed for contactless energy transmission. 
     A power tool with a receptacle region for a replaceable rechargeable battery unit is also proposed, which has a coupling unit that is provided for charging the replaceable rechargeable battery unit, and as a result, again as in the proposed replaceable rechargeable battery unit, convenient charging between uses can be attained. Once again, the coupling unit can be located in a region that despite the mounted state of the replaceable rechargeable battery unit is directly accessible or contactable, and/or it can be located in a covered region and designed for contactless energy transmission. 
     The coupling unit may be located in various regions that appear useful to one skilled in the art, for instance a rear region facing away from the tool receptacle region, or advantageously in some other region facing toward the tool receptacle region. The term “facing toward” should be understood to mean that the coupling unit is at least closer to the tool receptacle region than to an end of the power tool facing away from the receptacle region. By means of a suitable location, especially convenient coupling of the power tool to a charger, particularly in the machining direction, can be attained. 
     In a further feature, it is proposed that the replaceable rechargeable battery unit and/or the power tool, which will hereinafter be referred by the combined term power tool unit, has a covering means, which is provided for covering the coupling unit. As a result, the coupling unit can advantageously be protected against becoming soiled and damaged. 
     If the coupling unit is provided for contactless energy transmission, the covering means can be embodied immovably and can advantageously be embodied integrally with some other functional means, such as a housing part. However, if the coupling unit is provided for energy transmission via a mechanical contact, then especially convenient actuation of the covering means can be attained if the covering means is supported movably, for instance pivotably and/or displaceably. As an alternative to being supported movably, however, it would also be conceivable for the covering means to be detachably joined to the power tool unit. 
     If the covering means is kept captive on the power tool unit in both its covering position and its release position, then loss of the covering means, especially in a charging operation, can be reliably avoided. 
     If the covering means is provided for automatic movement into its release position upon a coupling operation to a charger, then additional manipulations by a user can be avoided, and the convenience can be further enhanced. 
     A charger with a coupling unit is also proposed, which is provided for correspondence with at least one coupling unit of a power tool unit of the invention, and which is embodied in particular as a stand for the power tool. The term “stand” is meant in particular to express the fact that the power tool can be positioned for charging in the charger while being held by its handle, and when it is positioned in the charger it can be removed again via its handle, which is at least essentially freely accessible. 
     If the charger has a receptacle region into which the power tool can be positioned at least essentially in the machining direction thereof, and in particular is inserted into it, then once again the convenience can be enhanced, especially because in its shape, the power tool is fundamentally designed for movement in its machining direction. However, it is also conceivable for the power tool to be provided, or in other words designed and/or equipped, to be inserted into the charger in the direction other than the machining direction. 
     It is furthermore proposed that the charger, besides a receptacle region for a power tool of the invention, has at least one receptacle region for a replaceable rechargeable battery unit, as a result of which one replaceable rechargeable battery unit can always be charged during operation of the power tool in parallel with another replaceable rechargeable battery unit, so that particularly in continuous actuation, energy transmission is always assured. 
     A power tool system with a replaceable rechargeable battery unit for a power tool of the invention and a power tool of the invention is also proposed, as a result of which the components can advantageously be adapted to one another. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Further advantages will become apparent from the ensuing drawing description. In the drawing, one exemplary embodiment of the invention is shown. The drawing, description and claims include numerous characteristics in combination. One skilled in the art will expediently consider the characteristics individually as well and put them together to make useful further combinations. 
       Shown are: 
         FIG. 1 , a first section through a charger in the region of a inserted power tool; 
         FIG. 2 , a second section through the charger in the region of an inserted replaceable rechargeable battery unit for a power tool; and 
         FIG. 3 , the charger from above, without the power tool and without the replaceable rechargeable battery unit. 
     
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       FIG. 1  shows a power tool  14 , formed by a pistol-like battery-powered drill. On an underside of the handle, a replaceable rechargeable battery unit  10   a  for a power tool is mounted on the power tool  14  in a corresponding receptacle region  44 . 
     In a front region, facing toward the tool receptacle region  18 , the power tool  14  has a coupling unit  16 , formed by charge contacts, which is provided for charging the replaceable rechargeable battery unit  10   a . For charging the replaceable rechargeable battery unit  10   a , the power tool  14  can be inserted, being held by its handle, in its machining direction  32  into a receptacle region  30  of a charger  24  embodied as a stand. The receptacle region  30  includes a receptacle region  38  for a tool  40  of the power tool  14 , so that the power tool together with the tool  40  can be inserted into the receptacle region  30  without having to remove the tool  40 . 
     While the power tool  14  is in operation, the coupling unit  16  is covered by a movably supported covering means  22 , formed by a slide, which upon insertion of the power tool  14  into the receptacle region  30  of the charger  24  comes to rest on a stop, not identified by reference numeral, of the charger and which by the insertion motion of the power tool  14  is automatically displaced to the rear into its release position, counter to the machining direction  32 , against a spring element  36 , so that the coupling unit  16  can come into contact with a corresponding coupling unit  28  of the charger  24 . In the state inserted into the charger  24 , the handle of the power tool  14  is freely accessible, so that being held by the handle it can conveniently pulled back out of the charger  24  again. On being pulled out, the covering means  22  is displaced by the spring element  36  back forward in the machining direction  32  into its covering position. The covering means  22  is kept captive on the power tool  14  in both its covering position and its release position. In addition or as an alternative to the coupling unit  16 , the power tool  14  may also have a permanently covered coupling unit  48 , located for instance under the housing of the power tool  14 , which is provided for contactless energy transmission and is only suggested by dashed lines in  FIG. 1 . 
     The replaceable rechargeable battery unit  10   a  further has a coupling unit  12   a , which is provided for charging the replaceable rechargeable battery unit  10   a  while the replaceable rechargeable battery unit is mounted on the power tool  14 . The coupling unit  12   a  is located at the bottom in a front region pointing in the machining direction  32 , of the replaceable rechargeable battery unit  10   a.    
     For charging in the mounted state on the power tool  14 , the replaceable rechargeable battery unit  10   a  can be inserted essentially perpendicular to the machining direction  32  of the power tool  14 , essentially in the axial direction of the handle of the power tool  14 , with its bottom region leading into a receptacle region  34  of the charger  24  ( FIGS. 1 through 3 ). However, the replaceable rechargeable battery unit  10   a  may also be inserted in the unmounted state, without the power tool  14 , into the receptacle region  34  for charging. In  FIG. 2 , a replaceable rechargeable battery unit  10   b  that is structurally identical to the replaceable rechargeable battery unit  10   a  is shown that is inserted into the receptacle region  34  without the power tool  14 . To illustrate the fact that the replaceable rechargeable battery unit  10   b  could also be charged in the mounted state on the power tool  14  directly via the coupling unit  12   b , the power tool  14  is shown only schematically in  FIG. 2 . For both replaceable rechargeable battery units  10   a ,  10   b , the same reference numerals have been used, but followed by the letters “a” and “b” to distinguish them. 
     During the operation of the power tool  14 , the coupling unit  12   a  is covered by a movably supported covering means  20   b , formed by a slide, which upon insertion of the replaceable rechargeable battery unit  10   b  into the receptacle region  34  of the charger  24  comes to rest on a stop, not identified by reference numeral, of the charger  24 , and is displaced by the insertion motion of the replaceable rechargeable battery unit  10   b  automatically into its release position in the direction of the power tool  14 , counter to a spring element  46   b , so that the coupling unit  12   b  can come into contact with a corresponding coupling unit  26  of the charger  24 . Once the replaceable rechargeable battery unit  10   b  has been inserted jointly with the power tool  14  into the receptacle region  34 , the handle of the power tool  14  is freely accessible, and so the replaceable rechargeable battery unit  10   b  can be conveniently pulled out of the charger  24  again, in that the power tool  14 , being held by its handle, is pulled essentially in the axial direction of its handle out of the receptacle region  34  together with the replaceable rechargeable battery unit  10   b . If the replaceable rechargeable battery unit  10   b  is inserted into the receptacle region  34  without the power tool  14 , then it can either be grasped by its housing that protrudes past the charger  24  or advantageously by a contact plug  42   b  that protrudes past the housing and pulled out of the receptacle region  34 . 
     On being pulled out, the covering means  20   b  is displaced by the spring element  46   b  back into its covering position, downward in the direction of the bottom region of the replaceable rechargeable battery unit  10   b . Both in its covering position and in its release position, the covering means  20   b  is kept captive on the replaceable rechargeable battery unit  10   b.    
     In addition or as an alternative to the coupling units  12   a ,  12   b , the replaceable rechargeable battery units  10   a ,  10   b  may also each have a respective permanently covered coupling unit  50   a ,  50   b , located for instance under the housing of the replaceable rechargeable battery units  10   a ,  10   b , these coupling units being provided for contactless energy transmission and being suggested only by dashed lines in  FIGS. 1 and 2 . 
     LIST OF REFERENCE NUMERALS 
     
         
         
           
               10  Replaceable rechargeable battery unit for a power tool 
               12  Coupling unit 
               14  Power tool 
               16  Coupling unit 
               18  Tool receptacle region 
               20  Covering means 
               22  Covering means 
               24  Charger 
               26  Coupling unit 
               28  Coupling unit 
               30  Receptacle region 
               32  Machining direction 
               34  Receptacle region 
               36  Spring element 
               38  Receptacle region 
               40  Tool 
               42  Contact plug 
               44  Receptacle region 
               46  Spring element 
               48  Coupling unit 
               50  Coupling unit