Abstract:
A motor-driven saber saw includes a housing ( 4 ), having a neck ( 8 ) which serves as a handle and has a tool opening ( 6 ), a guide device ( 22 ) for guiding the saber saw ( 2 ) on a workpiece and releasably connectable to the housing ( 4 ) in a region of the housing neck ( 8 ) and including a connection device ( 21 ) for connecting the guide device ( 22 ) to the housing ( 4 ), the housing ( 4 ) having connecting receptacles ( 18 ) for guiding the connection device ( 21 ), an adjusting device ( 30 ) mountable on the connection receptacles ( 18 ) for securing the connection device ( 21 ) to the housing, and a rectilinear spring member ( 36 ) for biasing the adjusting device ( 30 ) to a locking position and extending substantially in a longitudinal direction of the housing neck ( 8 ).

Description:
BACKGROUND OF THE INVENTION  
         [0001]    1. Field of the Invention  
           [0002]    The present invention relates to a motor driven saber saw including a housing having a neck that serves as a handle and has a tool opening, a guide for guiding the saber saw on a workpiece and releasably connectable to the housing in a region of the neck, the guide including a connection element for connecting the guide to the housing, with the housing having a connection receptacle for guiding the connection element, and an adjusting device mountable on the connection receptacle for securing the connection element to the housing and spring-biased to its locking position.  
           [0003]    2. Description of the Prior Art  
           [0004]    Known saber saws can usually be equipped with a guide such as a guide shoe or a tubular adapter in order to achieve a reliable and precise guidance of the saber saw on the workpiece. The guide permits to achieve a precise cut on the workpiece having at least regionwise a flat or round cross-section.  
           [0005]    U.S. Pat. No. 5,421,091 discloses a saber saw having a housing, a guide shoe for guiding the saber saw on a workpiece, and a pendulum-driven, with a motor, plunger. The guide shoe is pivotally supported at an end of a connection rail provided with an elongate recess, with the connection rail being guided in a substantially rectangular rail guide provided in the saw housing. For securing the connection rail on the saber saw, there is provided a locking member displaceable in a recess formed in the saw housing and extending transverse to the rail guide. The locking member is pressed against the guide rail with a helical spring arranged in the same recess as the locking member. The locking member engages, in its non-actuated condition, toothing provided on the connection rail. For adjusting the position of the guide shoe and releasing the guide shoe, the locking member is pressed against the helical spring, so that it becomes disengaged from the connection rail toothing.  
           [0006]    U.S. Pat. No. 6,317,988 discloses a saber saw having a guide shoe for guiding the saber saw on a workpiece, and in which the connection rail of the guide shoe is detached from the housing by a release of a clamping lever supported on the housing, and is brought into another position. Upon the connection rail being brought into another position, the clamping lever is again secured on the housing, with the clamping lever acting on a leaf spring that biases the connection rail, which now occupies a new position, against the housing, securing the connection rail to the housing.  
           [0007]    A drawback of both known solutions of securing the connection element of the guide shoe to the housing consist in that the securing means requires a relatively large mounting space. This is unacceptable because the adjusting device is located inside the housing neck that serves as a handle during the operation. A large cross-section of the housing neck often results in a very bad handle ergonomy.  
           [0008]    The conventional adjusting devices have a relatively expensive construction, or they can only be mounted in a housing that is expensive to produce. In both cases, the result is high manufacturing costs.  
           [0009]    Accordingly, an object of the present invention is to provide a saber saw with a guide in which the drawbacks of the conventional saber saw are eliminated.  
           [0010]    Another object of the present invention is to provide a saber saw with a guide in which the adjusting device occupies minimum space and which can be produced with relatively small manufacturing costs.  
         SUMMARY OF THE INVENTION  
         [0011]    These and other objects of the present invention, which will become apparent hereinafter, are achieved by providing a rectilinear spring member for biasing the locking member to its locking position and which extends substantially in a longitudinal direction of the housing neck.  
           [0012]    With such a spring member, a very flat mounting space is required for the adjusting device that flatly abuts the housing in the region of the housing neck. This permits to form the housing neck of the saber saw rather slim, which permits to provide a good handle ergonomy.  
           [0013]    Preferably, the rectilinear spring member is formed as a bar with elastic characteristics, which results in small costs of the material.  
           [0014]    Advantageously, all of the support regions of the adjusting device on the housing and the housing have a common release direction. This permits to form at least a section of the housing, on which the adjusting device is supported, rather simple so that it can be formed by a die casting process. This permits to dispense with expensive shoving or a second machining treatment, which noticeably reduces manufacturing costs. In addition, with a single release direction, the assembling of the saw is simplified.  
           [0015]    According to a particular advantageous embodiment of the present invention, the adjusting device is secured on the housing with a single fastening element. This makes possible a particularly simple mounting of the adjusting device on the housing, which against reduces the manufacturing costs.  
           [0016]    Advantageously, the fastening element is formed as a screw which, together with a rib provided on the housing, form a clamping device for securing the sprig member which again insures a cost-effective and simple mounting of the adjusting device.  
           [0017]    Advantageously, the adjusting device includes a locking member which is provided on a housing side and which extends in the locking position of the adjusting device through a housing opening and engages the connection means, and a rocking member having an actuation element at one of its ends an adjusting element at another, opposite of its ends and that upon the actuation element being pressed in a direction toward the housing side, displaces the locking member in a direction away from the housing side. This also noticeably reduces mounting of the adjusting device as all of its parts can be manually secured on the corresponding side of the housing from outside. This also insures an easy handling of the adjusting device.  
           [0018]    Further, the rocking member, preferably, is located in a support receptacle limited by the housing and a hand-protecting member securable thereon. In this way, the securing of the hand-protecting member on the housing provides for a long-lasting pivotal support of the rocking member on the housing, without a need in further attachment means, which again simplifies mounting of the adjusting device.  
           [0019]    It is advantageous when the hand-protecting member has a flexible region that in a mounted condition of the hand-protecting member lies on the actuation element of the rocking member. Such a flexible region can be formed by reducing the thickness of material in this region in comparison with other regions of the hand-protecting member or by using a lighter material for forming this region. In this way, in addition to sealing the drive against soiling from outside, a simple and reliable actuation of the adjusting device is insured.  
           [0020]    Advantageously, the flexible region has a rippled surface. This permits the operator, by using a sense of touch, to select the position of the flexible region and that of the actuation element, which improves handling of the adjusting device.  
           [0021]    The novel features of the present invention, which are considered as characteristic for the invention, are set forth in the appended claims. The invention itself, however both as to its construction and its mode of operation, together with additional advantages and objects thereof, will be best understood from the following detailed description of preferred embodiments, when read with reference to the accompanying drawings. 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0022]    The drawings show:  
         [0023]    [0023]FIG. 1 an exploded view of a bottom of a front section of a saber saw according to the present invention, together with a guide device and a hand-protecting member;  
         [0024]    [0024]FIG. 2 a bottom view of the bottom of the front section shown in FIG. 2 with the hand-protecting member being removed; and  
         [0025]    [0025]FIG. 3 a cross-sectional view along line III-III in FIG. 2. 
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT  
       [0026]    A motor-driven saber saw  2  according to the present invention, a front section of which is shown in FIGS. 1-3, includes a housing  4  provided with a neck  8  extending to an opening  6  through which during an operation, a push rod (not shown), together with a saw blade secured thereto, reciprocates. The neck  8  is used as a handle during the operation of the saber saw  2 .  
         [0027]    With the neck  8  being used as a handle, during the assembly of the sable saw  2 , a hand-protecting member  10  is pushed over the neck  8 . The hand-protecting member  10  is adapted to a hand of a human to a most possible extent. To this end, the hand-protecting member  10  is provided on its surface with finger troughs  12  which predetermine, to a most possible extent, the position of a hand holding the neck  8  during the operation. In the frontmost finger through  12  in which the forefinger of an operator is received, there is provided a flexible region  14  with a rippled surface. The rippled surface is formed by a plurality of parallel groove-shaped recesses which insure that the hand-protecting member  10  has, in the rippled region  14 , more elastic characteristics than in the remaining portion of the hand-protecting member  10 .  
         [0028]    In addition to the tool opening  6 , the housing  4  has a connecting device  16  in the form of two receiving receptacles  18  formed in the housing  4 . The receiving receptacles  18  have a circular cross-section. Two rod-shaped connection members  20  of a connection device  21  of a guide  22  are received in the receiving receptacles  18 . A connection web  24  connects the two rod-shaped connection members  20  with a guide shoe  26  which is pivotally secured on the connection web  24 . The two rod-shaped connection members  20  have, at their ends remote from the connection web  24 , a plurality of locking constrictions  27 .  
         [0029]    At the bottom side  28  of the housing  4 , there is further provided an adjusting device  30 . The adjusting device  30  secures the connection device  21  in the connecting device  16 . To this end, on the bottom side  28 , there are provided openings  32  connected with respective receiving receptacles  18 . A locking member  34  of the adjusting device  30  is displaced transverse to the receiving receptacle  18  at the openings  32 . The locking member  30  is supported displaceable between two guide ribs  35  of the housing  4 .  
         [0030]    The locking member  34  is biased in the direction of the receiving receptacles  18  by a rectilinear, bar-shaped spring member  36 . In its unloaded condition, the adjusting device  30  occupies a locking condition at which locking elements  38  of the locking members  34  project through respective openings  32  into the receiving receptacles  18 .  
         [0031]    For securing the rectilinear spring member  36 , on the bottom side  28  of the housing  4 , there is provided, adjacent to a housing rib  42 , a threaded receptacle  40 . The housing rib  42  forms, with a screw  44  screwed into the receptacle  40 , a clamping device  46 . During the assembly of the saber saw  2 , the spring member  36  is placed with its end on the housing rib  42 , and the screw  44  is screwed into he threaded receptacle  40 . In this way, the end of the spring member  36  is clamped between the housing  4 , the housing rib  42 , the screw head  48 , and the screw stem  50 . The spring member  36  occupies, in its clamping position, a position in which it extends parallel to the housing neck  8 , as can be seen in FIG. 2.  
         [0032]    Alternatively, to screwing the of the screw  44  in the threaded receptacle  40 , it is possible to screw a self-cutting screw directly into the housing  4 . The end of the spring member  36 , remote from the clamping device  46 , is received in an engagement tough  54  provided in the upper side  52  of the locking member  34 . An adjusting element  58  of a rocking member  60  engages a bearing surface  56  located opposite the engagement trough  54 . The adjusting element  58  is provided at an end of the rocking member  60  remote from the tool. The end of the rocking member  60  adjacent to the tool forms an actuation element  62  that is formed as a button. Between the adjusting element  58  and the actuation element  62 , the rocking member  60  has an approximate sleeve-shaped pivotal element  64 .  
         [0033]    During mounting of the adjusting device  30 , first, the pivotal element  64  of the rocking member  60  is placed in a correspondingly formed support receptacle  66  which is provided on the bottom side  28  of the housing  4 . Then, the locking member  34  is set between the two guide ribs  35 , with the bearing surface  56  of the locking member  34  abutting the adjusting element  58  of the rocking member  60 . Thereafter, the end of the spring member  36  is placed in the engagement trough  54  of the locking member  34 , with the opposite end of the sprig member  36  being placed against the housing rib  42 . Finally, the spring member  36  is clamped with the screw  44 , as it has been discussed above. As soon as the spring member  36  is clamped by the clamping device  46 , the entire adjusting device  30  becomes secured on the housing  4 . The screw  44  forms, thus, a single fastening element with which the adjusting device  30  is secured on the housing  4 .  
         [0034]    The support of the adjusting device  30  on the housing  4  is so effected that the threaded receptacle  40 , the guide ribs  35 , and the support receptacles  66  and, thereby, all of the support regions of the adjusting device  30  are oriented in a direction corresponding to a main removal direction of the adjusting device  30  from the housing  4 .  
         [0035]    After the adjusting device  30  has been mounted, the hand-protecting member  10  is pushed over the housing neck  8  and the adjusting device  30 , with the flexible region  14  being placed directly above the actuation element  62  of the rocking member  60 . In addition, the hand-protecting member  10  forms, together with the support receptacles  66 , a support for rotatably supporting the pivotal element  64  of the rocking member  60  on the housing  4 .  
         [0036]    In order to secure the guide device  22  on the saber saw  2 , an operator presses, with the forefinger, the flexible region  14  of the hand-protecting member  10 . Thereby, the actuation element  62  of the rocking member  60  is pressed against the bottom side  28  of the housing  4 , and the adjusting element  58  simultaneously moves away from the bottom side  28  and applies pressure against the bearing surface  56  of the locking member  3 , displacing the locking member  34  against the biasing force of the spring member  36 . Thereby, the locking member  34  is displaced form the receiving receptacles  18 , and the locking elements  38  move out of the receiving receptacles  18 . The adjusting device  30 , as a result, now occupies a release position in which the connection members  20  can be inserted into the connecting device  16 .  
         [0037]    As soon as a predetermined distance of the guide shoe  26  from the housing  4  is reached, the operator releases the pressure on the flexible region  14  of the hand-protecting member  10  and, thereby, on the actuation element  62  of the locking member  34 . As a result, a biasing force of the spring member  36  displaces the locking member  34  and its locking elements  38  through the openings  32  and into the receiving receptacle  18 . The locking elements  38  engage a respective locking construction  27 . This provides for securing the connection device  21  and, as a result, the entire guide device to the housing  4  in a desired position.  
         [0038]    Though the present invention was shown and described with references to the preferred embodiment, such is merely illustrative of the present invention and are not to be construed as a limitation thereof and various modifications of the present invention will be apparent to those skilled in the art. It is, therefore, not intended that the present invention be limited to the disclosed embodiment or details thereof, and the present invention includes all variations and/or alternative embodiments within the spirit and scope of the present invention as defined by the appended claims.