Abstract:
A device system, including a remote control ( 13 ) having a device housing ( 31 ) and a first radio unit ( 38 ), a tool device with a second radio unit and a radio link which connects the first radio unit ( 38 ) of the remote control ( 13 ) to the second radio unit of the tool device. The first radio unit is ( 38 ) is arranged on a front side ( 57 ) of the device housing ( 31 ), wherein the front side ( 57 ) is lying opposite a rear side ( 56 ) of the device housing ( 31 ) facing the operator in a working position of the remote control ( 13 ).

Description:
[0001]    The present invention relates to a device system which includes a radio link. 
       BACKGROUND 
       [0002]    HUSQVARNA offers a device system including a remote control, which is connectable to the device system via a radio link wirelessly and without cables. The device system is designed as a wall sawing system and includes a guide rail, a tool device displaceably situated on the guide rail, an electronic assembly and the remote control. The tool device is designed as a wall saw and includes a saw head and a motor-driven feed unit. The saw head includes a cutting tool, which is designed as a saw blade, and is driven around a rotation axis by a drive motor. The motor-driven feed unit includes a guide carriage and a feed motor; the saw head is situated on the guide carriage and displaced on the guide rail by the feed motor along a feed direction. 
         [0003]    The remote control includes a device housing, an input device, a display device and a first control unit, which is situated in the interior of the device housing. The first control unit converts the inputs via the input device into control commands and data which are transmitted to the electronic assembly via a first communication link. The first communication link is designed as either a radio link or a first communication cable. The first communication cable is used if a wireless or cableless communication is not possible for safety reasons or due to sources of interference. The first communication cable is also used to clearly assign the remote control and the electronic assembly to each other. 
         [0004]    The radio link forms between a first radio unit on the remote control and a second radio unit on the electronic assembly. The first radio unit includes a radio module having a first radio antenna, and the second radio unit includes a radio module having a second radio antenna. The first radio unit is situated in the device housing of the remote control, between a lower side of the device housing and the horizontally arranged first control unit, and the second radio unit is situated in the device housing of the electronic assembly, which is manufactured primarily from metal. The arrangement of the first and second radio units may impair the radio link. 
       SUMMARY OF THE INVENTION 
       [0005]    It is an object of the present invention to increase the reliability of the radio link in a remote control which is connectable to a device system wirelessly and without cables via a radio link between a first radio unit and a second radio unit. The radio link is to have a sufficient reliability, in particular in device systems without a separate electronic assembly. 
         [0006]    According to the present invention, the first radio unit is situated on a front side of the device housing, the front side being opposite a back side of the device housing facing the operator in a working position of the remote control. 
         [0007]    The arrangement of the first radio unit on the front side of the device housing has the advantage that the front side represents the device side facing away from the operator. The front side of the device housing is also facing the tool device in the working position of the remote control. During cutting, the operator holds the remote control in the working position and directs his gaze to the cutting process. 
         [0008]    The first radio unit preferably includes a first radio module having a first radio antenna and a second radio module having a second radio antenna, the polarization directions of the first and second radio antennas being situated essentially perpendicularly to each other. Due to the use of multiple radio modules having perpendicular radio antennas, the quality of the radio link between the remote control and the tool device may be improved. 
         [0009]    The first and second radio module particularly preferably have an identical design. By using identical radio modules, the device costs for setting up of the radio link may be reduced. 
         [0010]    In one preferred refinement, the first radio unit includes a third radio module having a third radio antenna, the polarization direction of the third radio antenna being situated essentially perpendicularly to the polarization directions of the first and second radio antennas. Due to the use of a third radio module having a perpendicular radio antenna to the radio antennas, the quality of the radio link between the remote control and the tool device may be improved. The radio antennas situated perpendicularly to each other span a three-dimensional space. 
         [0011]    The distance between the first antenna base point of the first radio module and the second antenna base point of the second radio module particularly preferably essentially corresponds to an odd multiple of a quarter wavelength of a radio frequency. 
         [0012]    The radio link between the remote control and the tool device has a frequency band including multiple radio frequencies between a lower radio frequency and an upper radio frequency. The distance between the first antenna base point of the first radio module and the second antenna base point of the second radio module is matched to the center frequency of the frequency band. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0013]    Exemplary embodiments of the present invention are described below on the basis of the drawing. The latter is not necessarily intended to represent the exemplary embodiments true to scale but rather the drawing is presented in a schematic and/or slightly distorted form where useful for the purpose of explanation. With regard to additions to the teachings apparent from the drawing, reference is hereby made to the relevant prior art. It should be taken into account that a variety of modifications and changes relating to the form and detail of a specific embodiment may be undertaken without deviating from the general idea of the present invention. The features of the present invention disclosed in the description, the drawing and the claims may be essential to the refinement of the present invention both individually and in any combination. All combinations of at least two of the features disclosed in the description, the drawing, and/or the claims are also within the scope of the present invention. The general idea of the present invention is not limited to the exact form or the detail of the preferred specific embodiment illustrated and described below, nor is it limited to an object which would be limited in comparison to the object claimed in the claims. In given measurement ranges, values within the specified limits are also to be disclosed as limiting values and be able to be arbitrarily used and claimed. For the sake of simplicity, the same reference numerals are used below for identical or similar parts or for parts having identical or similar functions. 
           [0014]      FIG. 1  shows a device system according to the present invention, which is designed as a wall sawing system, including a remote control and a tool device, which are connectable to each other via a radio link; 
           [0015]      FIGS. 2A, 2B  show the use of the wall sawing system according to the present invention from  FIG. 1  during the cutting of a concrete wall in a vertical arrangement ( FIG. 2A ) and in a horizontal arrangement ( FIG. 2B ); 
           [0016]      FIGS. 3A, 3B  show the remote control from  FIG. 1  in a view of an upper side of the device housing ( FIG. 3A ) and in a view of a front side of the device housing ( FIG. 3B ). 
       
    
    
     DETAILED DESCRIPTION 
       [0017]      FIG. 1  shows a device system  10  according to the present invention, which is designed as a wall sawing system. Wall sawing system  10  includes a guide rail  11 , a tool device  12 , which is displaceably situated on guide rail  11 , and a remote control  13 . The tool device is designed as a wall saw  12  and includes a cutting unit  14  and a motor-driven feed unit  15 . The cutting unit is designed as a saw head  14  and includes a cutting tool  16  designed as a saw blade, which is fastened to a saw arm  17  and is driven around a rotation axis  19  by a drive motor  18 . 
         [0018]    To protect the operator, saw blade  16  may be surrounded by a saw blade guard, which is fastened on saw arm  17  with the aid of a blade guard holder. Saw arm  17  is designed to be pivotable around a pivot axis  22  with the aid of a swing motor  21 . The pivot angle of saw arm  17  determines, with the aid of a saw blade diameter of saw blade  16 , how deep saw blade  16  dips into a workpiece  23  to be cut. Drive motor  18  and swing motor  21  are situated in a device housing  24 . Motor-driven feed unit  15  includes a guide carriage  25  and a feed motor  26 , which is also situated in device housing  24 . Saw head  14  is fastened on guide carriage  25  and is designed to be displaceable by feed motor  26  along guide rail  11  in a feed direction  27 . In addition to motors  19 ,  21 ,  25 , a control unit  28  for controlling saw head  14  and motor-driven feed unit  15  is also situated in device housing  24 . At least one handle  29  is provided on device housing  24 . 
         [0019]    Remote control  13  includes a device housing  31 , an input device  32 , a display device  33  and a control unit  34 , which is situated in the interior of device housing  31 . Control unit  34  converts the inputs of input device  32  into control signals and data, which are transmitted to wall saw  12  via a communication link. In addition to input device  32 , remote control  13  also includes a control element  35  designed as an emergency off switch. 
         [0020]    The communication link is designed as a wireless and cableless communication link  36  or as a communication cable  37 . The wireless and cableless communication link is designed in the exemplary embodiment as a radio link  36 , which forms between a first radio unit  38  on remote control  13  and a second radio unit  39  on tool device  12 . Communication cable  37  is used, in particular, when a wireless and cableless communication is prohibited for safety reasons, for example in hospitals and airports, or when sources of interference hinder the wireless and cableless communication. 
         [0021]      FIGS. 2A, 2B  show the use of wall sawing system  10  according to the present invention from  FIG. 1  during the cutting of a concrete wall in a vertical arrangement of wall sawing system  10  ( FIG. 2A ) and in a horizontal arrangement of wall sawing system  10  ( FIG. 2B ). 
         [0022]      FIG. 2A  shows wall sawing system  10 , including guide rail  11  of wall saw  12  and remote control  13 , during the cutting of a first concrete wall  41 . Guide rail  11  is fastened on first concrete wall  41  in a vertical direction  42 . The operator holds remote control  13  in his hands in a working position and directs his gaze onto the cutting work on wall  41 . 
         [0023]      FIG. 2B  shows wall sawing system  10 , including guide rail  11 , wall saw  12  and remote control  13 , during the cutting of a second concrete wall  43 . Guide rail  11  is fastened on second concrete wall  43  in a horizontal direction  44 . The operator holds remote control  13  in his hands in a working position and directs his gaze onto the cutting work on wall  43 . 
         [0024]    Radio link  36  between remote control  13  and wall saw  12  is impaired by various factors. During cutting, a cooling and rinsing fluid is used, which makes the surface to be cut and adjacent areas wet. The blade guard and saw blade  16 , both of which are manufactured from metal, also impair radio link  37 . 
         [0025]      FIGS. 3A, 3B  show remote control  13  in an oblique view of an upper side ( FIG. 3A ) of remote control  13  and in a view of a front side thereof ( FIG. 3B ). Remote control  13  is part of device system  10  according to the present invention from  FIG. 1 . 
         [0026]    Remote control  13  includes device housing  31 , input device  32 , display device  33  and control unit  34 , which is situated in the interior of device housing  31 . Input device  32  includes multiple input elements, which are designed as joystick  51 , as knob  52  and as pushbuttons  53 . Depending on device system  10  and the complexity of the cutting method, the operator must set different cutting and device parameters. Input device  32  may therefore include additional input elements besides the input elements shown in  FIG. 2A . 
         [0027]    Device housing  31  includes an upper side  54 , a lower side  55 , which is opposite upper side  54 , a back side  56 , a front side  57 , which is opposite back side  56 , a left side surface  58  and a right side surface  59 . Input device  32  and display device  33  are situated on upper side  54 . 
         [0028]    To ensure a secure grip during the remote control operation, device housing  31  includes two side holding elements  61 ,  62 , which are mounted on left side surface  58  and right side surface  59 . The side holding element mounted on left side surface  58  is also referred to as left holding element  61 , and the side holding element mounted on right side surface  59  is also referred to as right holding element  62 . The remote control of wall sawing system  10  takes place with the aid of remote control  13 , which the operator holds in the working position illustrated in  FIGS. 2A, 2B  during the operation of wall sawing system  10 . In the working position, the operator grips the side holding elements with the inner surfaces of his hands and operates the two input elements  51 ,  52  with his thumbs. Joystick  51  is operated with the thumb of the left hand, and knob  52  is operated with the thumb of the right hand. 
         [0029]    Control unit  34  converts the inputs of input device  32  into control commands and data, which are transmitted to wall saw  12  via the first communication link. The first communication link is designed as radio link  36  between first and second radio units  38 ,  39  or as communication cable  37 . First radio unit  38  is provided in device housing  31  of remote control  13 . In the exemplary embodiment in  FIG. 3B , first radio unit  38  includes a first radio module  63  having a first radio antenna  64  and a second radio module  65  having a second radio antenna  66 , the polarization directions of first and second radio antennas  64 ,  66  being situated essentially perpendicularly to each other. In the exemplary embodiment in  FIG. 3B , first and second radio modules  63 ,  65  have an identical design. To situate the polarization directions of the two radio antennas  64 ,  66  perpendicularly to each other, second radio module  65  is shifted with respect to first radio module  63  in device housing  31  and situated in a rotated manner. 
         [0030]    To set up radio link  36 , a frequency band having multiple radio frequencies is used between a lower radio frequency f min  and an upper radio frequency f max . If 15 equidistant radio frequencies are used between a lower radio frequency f min  of 2.405 GHz and an upper radio frequency f max  of 2.475 GHz, this results in a center frequency of 2.440 GHz. 
         [0031]    The distance between the base point of the first radio antenna and the base point of the second radio antenna corresponds to an odd multiple of a quarter wavelength of a radio frequency of 2.440 GHz.