KISSsys 03/2015 Instruction 010 Positioning 07/04/2015 KISSsoft AG Rosengartenstrasse 4 8608 Bubikon Switzerland Tel: +41 55 254 20 50 Fax: +41 55 254 20 51 info@kisssoft.ag www.kisssoft.ag
Contents 1. Introduction... 3 2. Summary... 3 3. Position and Unit Vectors... 3 4. Positioning of Force Elements... 4 4.1 Manual Positioning... 4 4.2 Positioning using the Shaft Editor... 5 4.3 Relative Positioning... 5 5. Positioning of the other Elements... 7 5.1 Simple Positioning... 7 5.2 Positioning of single Shafts... 7 5.2.1 Own Input... 7 5.2.2 Parallel to Shaft/Group... 7 5.2.3 According to Bevel Gears... 9 5.2.4 According to Face Gears... 10 5.2.5 According to Worm Gears... 11 5.2.6 Parallel to Two Shafts... 12 5.2.7 According to Gear Pair... 12 5.3 Positioning of coaxial Shafts... 12 26.04.2016 2 / 12
1. Introduction Machine elements have to be positioned in space correctly to assure a proper positioning of the forces and the correct layout in 3D representation. This instruction will explain how to position the most important elements. There are several ways to set, create or evaluate the positions in KISSsys model. There is no right and wrong way to do it. The approach depends on the model itself, but also on the user. 2. Summary There are mainly two kinds of positioning procedures: The positioning of the shafts in the layout and the positioning of the machine elements on the shafts. Every KISSsys main element (shaft, group and casing) can be positioned manually in the space element. This method is not very user friendly and should be avoided. Although at the moment it is the only possibility to position a casing in a model. It is either possible to define a parallel orientation of two shafts or to define the position with the tooth meshing e.g. according to worm or bevel gears. The elements can be moved on the parent shaft either by drag and drop in the shaft editor or by using the variable position in KISSsys. 3. Position and Unit Vectors Every KISSsys element (e.g. a shaft) can be positioned in the space related to the parent object (e.g. a group). The position is shown in the properties dialog of the element. The position and orientation can be also changed here if no other positioning for the element is given (this will be explained later). A right-click on the element and the choice of Properties shows the following dialog: Figure 3.1 Positioning using the properties 26.04.2016 3 / 12
The cartesian coordinates of the selected element are shown in Position -fields of the Properties. The reference is hereby on the coordinate system of the parent element (e.g. the group one level up in the tree). The orientation of the coordinate system is given in normal vectors; they show the directions of the x- and y- axis, defining the direction of the plane (x-y-plane). In the example Gear1 is positioned 55 mm displaced on the positive y-axis of the parent element (shaft). The directions of the x- and y-axis are identical to the directions of the coordinate system of the parent (x-axis = [1,0,0], y-axis = [0,1,0]). In case of ksysforceelements these positions and orientation vectors will be automatically redefined based on the parent shaft and therefore even if it is possible to change the values locally here, the next refresh will set the original values back. In case of shafts, groups or a casing element user may be able to change these values to set the position and orientation of the particular element in the space correctly. 4. Positioning of Force Elements The methods of positioning the elements (ksysforceelement) in KISSsys can be divided in three parts. Every element contains the variable position, which defines the position of the elements on the shaft along the positive y-axis (orientation of the element = orientation of the element on the shaft). 4.1 Manual Positioning Every force element has a variable position, which defined the position of the element from the starting point of the parent shaft. This value can be manually given under the Properties window. When the value is set, the next refresh will move the element in the given position in e.g. to be seen in the ksys3dview. Figure 4.1 Variable position for the ksysforceelement 26.04.2016 4 / 12
If the flags between KISSsoft and KISSsys are set, the given value can be updated from KISSsoft shaft calculation to the model or vice versa. 4.2 Positioning using the Shaft Editor If the model includes a shaft calculation module, the connected shaft with its elements can be defined and positioned using the graphical KISSsoft shaft editor. In most cases this is the easiest way to set the positions of the elements correctly on each shaft. Figure 4.2 Position of the gear defined in the shaft editor Now if the flag KISSsoft-> KISSsys is set for the variable position on the gear element, the given position is automatically transferred and updated in the KISSsys model. Note: The flags are set on default so that the values are transferred correctly. 4.3 Relative Positioning In some cases it may be necessary to set the position of the element relative to the position of any other element in the model. This maybe case e.g. when gear should always remain in mesh independent to the position of the mating pinion. In other words user can modify the position of the pinion gear in the system and the position of the gear should always be recalculated so that the positions of the shafts do not change. There is a class function called l_p(reference element, point on parent element), which can be used in this case. 26.04.2016 5 / 12
Figure 4.3 Relative position of the gear2 (red) between the gear1 (green) and starting point of the shaft2 In the example, the positions of the shafts are fixed (no axial movement allowed), the position of the pinion can be defined in the shaft editor (see picture above) and based on this the position of the gear shall be automatically set on the second shaft. Figure 4.4 Position of gear1 (z1) in relation to the position of gear2 (z2) Now the expression will be always evaluated and therefore the shaft editor for the second shaft cannot be used anymore to define the position of the second gear. Removing the expression will set the original position again. 26.04.2016 6 / 12
5. Positioning of the other Elements This section describes the positioning for the shafts, groups and the casing/housing. 5.1 Simple Positioning The main elements in KISSsys ( ksysshaft, ksysgroup and ksyscasing ) can be positioned using the manual positioning via the properties. These KISSsys elements can be positioned in space related to the parent object (e.g. a group). The position is shown in the properties dialog of the element. The position and orientation can be also changed here (see chapter 3). This will not apply for the coaxial shaft elements, because the position of this type shaft is defined automatically parallel to the parent group. 5.2 Positioning of single Shafts The positions of gear box elements are, in majority, defined by the placement of the shafts. Due to that reason pre-programmed functions make the positioning of these shafts easier. A right-click on the shaft and the choice of Dialog shows you the positioning window, which contains 7 positioning functions. Once the positioning function for the shaft is selected, the reselection of the function Dialog will open the dialog showing the definition. If the positioning method should be fully changed, please use function ResetPosition to fully redefine the positioning method. Figure 5.1 Positioning of a shaft Note: As soon as a positioning function apart from own input is active, it is not possible anymore to position the elements using their properties. 5.2.1 Own Input Own Input is the command which activates the manual positioning described in the chapter 3 and 5.1. 5.2.2 Parallel to Shaft/Group This command allows the positioning of a one shaft parallel to another shaft or group. With the choice of this command and the click on OK will open the following dialog for the positioning: Figure 5.2 Parallel to shaft/group dialog 26.04.2016 7 / 12
Input Element Coordinates x/r y/phi z/y Function Selection of the reference element for the positioning. (parallel element) Indication if the positioning is made in Cartesian or Polar coordinates. Cartesian x / Polar r (Radius) Cartesian y / Polar Phi (Position angle measured from x-axis) Cartesian z / Polar y It is also possible to take a group as a reference. The y-axis of the shaft or the group, which has to be positioned, is then set parallel to the y-axis of the reference shaft or group in the same direction. Figure 5.3 Cartesian and polar coordinate definition Shaft positioning always defines the position of the shaft in x and z coordinate direction referenced to the position of the reference element. Additionally the distance between the shaft starting positions in y- direction (axial direction) is to be defined. Figure 5.4 Axial position There is also the possibility to invert the shaft direction referenced to another shaft. Variable direction type real or list is needed in this case on the shaft element having two different options. Value 0 or index 0 = parallel and value 1 or index 1 = opposite direction. If this variable exists, then the shaft direction can be inverted automatically 26.04.2016 8 / 12
5.2.3 According to Bevel Gears This is the command for the orientation of the shaft according to the tooth contact between bevel gears. The necessary data is entered in the following dialog: Figure 5.5 Positioning according bevel gears Input Gear on shaft In contact with Angle of contact Function The gear on shaft, which has to be oriented The fixed gear Defines the angle between the y-axis of the bevel gear and the positive x axis of the contact gear. z x angle of axes Angle between the two y-axis Centre distance Possible displacement for hypoid gears 26.04.2016 9 / 12
Note: Always differ between drive and coast side for spiral bevel gears. Drive side running means that the helix angle and the rotation direction of the pinion match (view: from the tip of the cone). 5.2.4 According to Face Gears This is the command for the orientation of the shaft according the tooth contact between helical gear and face gear. The necessary data is entered in the following dialog: Figure 5.6 Positioning according to face gears Input Bevel Gear In contact with Angle of contact Function The gear on shaft, which has to be oriented The fixed gear Defines the angle between the y-axis of the bevel gear and the positive x axis of the contact gear. Position of contact Defines if the contact is in front of or back side the gear offset Possible displacement Note: You may do the positioning according to pinion or gear element. The shaft angle in the face gear orientation is always 90 degrees. 26.04.2016 10 / 12
5.2.5 According to Worm Gears This is the command for the positioning of a worm and its gear. The parameters for the positioning are entered as follows: Figure 5.7 Positioning according to worm gears Input Worm/WormGear in contact with center distance angle of contact Function The gear which has to be oriented The fixed element center distance Z1 angle of axes Position on the circumference of the reference diameter of the Worm/Worm Gear. Angle between the two shaft axes to each other (for crossed helical gears). Y1 Y2 26.04.2016 11 / 12
5.2.6 Parallel to Two Shafts This command calculates the positioning of an intermediate shaft between two other shafts. Figure 5.8 Positioning parallel to two shafts Input Function Shaft 1 First reference shaft Shaft 2 Second reference shaft a1 Centre distance between intermediate shaft and shaft 1 a2 Centre distance between intermediate shaft and shaft 2 y Position of the coordinate system of the intermediate shaft, with shaft 1 as reference Direction Which one of the two cutting points between the two centre distances should be taken? Note: As soon as a positioning function is active, it is not possible anymore to position the elements using their properties. 5.2.7 According to Gear Pair One of the most common ways to define the shaft position in the space is to use gear pair meshing as a definition. The function according to gear pair allows users to select any existing gear mesh on the shaft to be used as the basis for the definition. Users need to first select what is the existing gear mesh to be considered and after that either fixed values for the centre distance and axial position can be calculated for the gears or formulas based on the gear pair centre distance, angular position and gear axial positions can be selected. After this selection the same dialog as for the function Parallel to Shaft/Group will be used. Last but not least the initial definition of the values can be freely modified by the user in the appearing dialog. 5.3 Positioning of coaxial Shafts The positioning of the coaxial shafts is automatically made inside the parent group they belong to. This means the ksysgroup defined one level higher in the model tree hierarchy. The positioning is based on the variable position defined in the coaxial shaft element. This is the same axial positioning available in the KISSsoft shaft editor. The position zero (0) means that the shaft is starting at the same global position where the group is defined. If the flag KISSsoft-KISSsys is activated, the defined position in the shaft editor is returned to the model and the shaft will be automatically positioned axially in the correct place. Note: For the coaxial shafts the shaft positioning functions described in above chapters are not working. Instead the whole coaxial shaft group is to be positioned according one of these functions to define the layout correctly. 26.04.2016 12 / 12