Patent Abstract:
An operating shift apparatus for a transmission may improve shift feeling using variable rotational inertia according to rotation. The operating shift apparatus for a transmission may include a control shaft is disposed on a transmission case, a select lever which is connected to the control shaft and selects a shift gear, a shift lever which is connected to the control shaft and engages the selected shift gear and a weight disposed to the shift lever for enhancing rotational inertia of the shift lever, wherein the shift lever and the weight are independently formed.

Full Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     The present application claims the priority of Korean Patent Application Number 10-2011-0080323 filed Aug. 11, 2011, the entire contents of which application is incorporated herein for all purposes by this reference. 
     BACKGROUND OF INVENTION 
     1. Field of Invention 
     The present invention relates to an operating shift apparatus for a transmission. More particularly, the present invention relates to an operating shift apparatus for a transmission which may improve shift feeling using variable rotational inertia according to rotation. 
     2. Description of Related Art 
     Generally a transmission is disposed between a clutch of a vehicle and a drive shaft for receiving rotational speed of an engine and shifting the rotational speed. Particularly, an operating shift apparatus is mounted to a manual transmission for a driver to manipulate the transmission according to running state of a vehicle. 
     The operating shift apparatus is connected to a shift lever through a control cable and allows manipulating operation of a transmission. The operating shift apparatus includes a select lever selecting shift gears and a shift lever engaging the selected shift gear a control shaft operated by the select lever and the shift lever. 
     A weight is integrally formed to the shift lever. And thus, mass of the weight may increase rotational inertia when the shift lever rotates, so that shift feeling may be improved. 
     However, the shift lever and the weight are integrally formed, and thus constant rotational inertia may be realized relationless shift stages. That is, when weight and position of the weight is determined, constant rotational inertia is determined. And thus, shift characteristic, according to shift stages or kind of a vehicle, may not be reflected according. Also, alteration of position of the weight may be limited and thus rotational inertia is proportional to weight of the weight. 
     The information disclosed in this Background section is only for enhancement of understanding of the general background of the invention and should not be taken as an acknowledgement or any form of suggestion that this information forms the prior art already known to a person skilled in the art. 
     SUMMARY OF INVENTION 
     Various aspects of the present invention provide for an operating shift apparatus which may vary rotational inertia of a shift lever. 
     Also, the present invention has been made in an effort to provide an operating shift apparatus which may reduce total weight of the apparatus. 
     An operating shift apparatus for a transmission of which a control shaft is disposed to a transmission case, the operating shaft apparatus according to various aspects of the present invention may include a select lever which is connected to the control shaft and selects a shift gear, a shift lever which is connected to the control shaft and engages the selected shift gear and a weight disposed to the shift lever for enhancing rotational inertia of the shift lever, wherein the shift lever and the weight are independently formed. 
     The shift lever may rotate on the control shaft integral with the control shaft. 
     The weight may rotate dependently according to rotation of the shift lever. 
     The weight and the shift lever may rotate on different rotation axis and each may have different angle of rotation. 
     The rotation axis of the weight may be formed to a predetermined position of the transmission case. 
     Ratio of the angles of rotation of the shift lever and the weight may be variable according to the rotation axis of the weight. 
     The operating shaft apparatus may further include an extended portion protruded from the shift lever and a guide hole formed to the extended portion. 
     A connecting protrusion, inserted into the guide hole, may be formed to the weight. 
     The connecting protrusion may be slidably movable within the guide hole for the weight easily to rotate dependently according to rotation of the shift lever. 
     Ratio of the angles of rotation of the shift lever and the weight may be variable according to shape of the extended portion and position of the guide hole. 
     The operating shaft apparatus may further include an extended portion protruded from the shift lever and a connecting protrusion formed to the extended portion. 
     A guide hole may be formed to the weight for the connecting protrusion to be inserted therein. 
     The connecting protrusion may be slidably movable within the guide hole for the weight easily to rotate dependently according to rotation of the shift lever. 
     Ratio of the angles of rotation of the shift lever and the weight may be variable according to shape of the extended portion and position of the connecting protrusion. 
     Relative rotation angle of the weight may be gradually reduced during the shift lever rotates for realizing shift. 
     The rotational inertia of the shift lever may be gradually reduced during the relative rotation angle of the weight is gradually reduced. 
     According to various aspects of the present invention, in rotation of a shift lever, relatively small weight may realize relatively large rotational inertia using lever ration of the shift lever and weight. And thus, total weight of the apparatus may be reduced. 
     The lever ratio may be variable according to rotation of the shift lever and weight. And thus the rotational inertia of the shift lever may be changed during shift stage. And thus, driver&#39; shift feeling may be improved. 
     The methods and apparatuses of the present invention have other features and advantages which will be apparent from or are set forth in more detail in the accompanying drawings, which are incorporated herein, and the following Detailed Description, which together serve to explain certain principles of the present invention. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a perspective view of an operating shift apparatus for an exemplary transmission according to the present invention. 
         FIG. 2  is a top plan view of an operating shift apparatus for an exemplary transmission according to the present invention. 
         FIG. 3  is a drawing showing each stage of rotation operation of an operating shift apparatus for an exemplary transmission according to the present invention. 
     
    
    
     DETAILED DESCRIPTION 
     Reference will now be made in detail to various embodiments of the present invention(s), examples of which are illustrated in the accompanying drawings and described below. While the invention(s) will be described in conjunction with exemplary embodiments, it will be understood that present description is not intended to limit the invention(s) to those exemplary embodiments. On the contrary, the invention(s) is/are intended to cover not only the exemplary embodiments, but also various alternatives, modifications, equivalents and other embodiments, which may be included within the spirit and scope of the invention as defined by the appended claims. 
       FIG. 1  is a perspective view of an operating shift apparatus for a transmission according to various embodiments of the present invention. 
     As shown in  FIG. 1 , an operating shift apparatus  10  for a transmission according to various embodiments of the present invention includes a control shaft  50 , a transmission case  60 , a select lever  40 , a shift lever  20  and a weight  30 . 
     The control shaft  50  is mounted to the transmission case  60  and connected with the select lever  40  and the shift lever  20 . That is, the control shaft  50  is connected with the select lever  40  and the shift lever  20  within the transmission case  60  and realizes selecting shift gears and engages the shift gears. 
     The select lever  40  is connected with the control shaft  50  and selects shift gears and the shift lever  20  is connected with the control shaft  50  and engages the shift gears. The select lever  40  and the shift lever  20  are connected with a manual lever, of which a driver manipulates, through a control cable. 
     A select lever rotating shaft  42  may be vertical to the control shaft  50 . And thus, when the select lever  40  rotates, the control shaft  50  or parts of the control shaft  50  moves along length direction of the control shaft  50 . A shift lever rotating shaft  22  may rotate on the control shaft  50 . And thus, the shift lever  20  may rotate integrally with the control shaft  50  around the control shaft  50 . Relationship and construction of the select lever  40 , the shift lever  20  and the control shaft  50  are obvious to a person skilled in the art, and thus detailed description will be omitted. 
     The shift lever  20  includes the shift lever rotating shaft  22 , a cable protrusion  23 , an extended portion  24  and a guide hole  26 . 
     The shift lever rotating shaft  22  is connected to the control shaft  50 . That is, the shift lever rotating shaft  22  is coincide with shaft center of the control shaft  50  or connected with the control shaft  50  to rotate the control shaft  50 . 
     The cable protrusion  23  is formed to a predetermined position of the shift lever  20  for connecting the shift lever  20  with a manual lever, of which a driver manipulate, through a control cable. The cable protrusion  23  is protruded from the shift lever  20  for connecting the cable. 
     The extended portion  24  may be integral to, and or monolitically formed with the shift lever  20  or may be formed for rotating with the shift lever  20  integrally. The extended portion  24  may be protruded parallel to rotating direction of the shift lever  20 . In  FIG. 1 , the extended portion  24  is formed as a plate, but it&#39;s shape is not limited as shown. 
     The guide hole  26  is formed to the extended portion  24  for connecting the shift lever  20  with the weight  30 . 
     The weight  30  includes a weight rotating shaft  32  and a connecting protrusion  36 . 
     The weight rotating shaft  32  is formed to the weight  30  and connected to a predetermined position of the transmission case  60  or the weight rotating shaft  32  is formed to a predetermined position of the transmission case  60  and is connected to the weight  30 . That is, rotation center of the weight  30  is different of that of the shift lever  20 . 
     The connecting protrusion  36  is formed to the weight  30  and is inserted into the guide hole  26 . That is, the shift lever  20  the weight  30  are connected by the connecting protrusion  36  and the guide hole  26 . The weight  30  rotates dependently to rotation of the shift lever  20 . The connecting protrusion  36  is slidably movable within the guide hole  26  for the weight  30  easily to rotate dependently according to rotation of the shift lever  20 . That is, the guide hole  26  is formed to allow the connecting protrusion  36  moving within the guide hole  26  in predetermined distance. 
     While the guide hole  26  is formed to the extended portion  24  and the connecting protrusion  36  is formed to the weight  30  in  FIG. 1 , however the connecting protrusion  36  may be formed to the extended portion  24  and the guide hole  26  may be formed to the weight  30 . 
       FIG. 2  is a top plan view of an operating shift apparatus for a transmission according to various embodiments of the present invention. 
     As shown in  FIG. 2 , the shift lever  20  and the weight  30  rotate simultaneously with each different rotation angle. 
     The cable protrusion  23  rotates on the shift lever rotating shaft  22  and the connecting protrusion  36  rotates on the weight rotating shaft  32 . The cable protrusion  23  and the connecting protrusion  36  are separated each other in predetermined distance. 
     Rotation centers of the shift lever  20  and the weight  30  are not equal, and the cable protrusion  23  and the connecting protrusion  36  are separated, and thus ratio of the angles of rotation of the shift lever  20  and the weight  30  are variable. The ratio of the angles of rotation of the shift lever  20  and the weight  30  may be lever ratio of the shift lever  20  and the weight  30  and the rotational inertia of the shift lever  20  may be variable according to the lever ratio. 
     The lever ratio may be variable according to distance between the cable protrusion  23  and the connecting protrusion  36  and distance between the shift lever rotating shaft  22  and the weight rotating shaft  32 . That is, the lever ratio may be changed according to shape of the extended portion  24  and position of the guide hole  26 , and position of the weight rotating shaft  32 . 
     In  FIG. 2 , L 1  and L 1 ′ denote lines connecting the shift lever rotating shaft  22  and the connecting protrusion  36  before and after moving and A 1  denotes angle between the L 1  and L 1 ′. That is, the A 1  denotes rotation angle of the shift lever  20 . L 2  and L 2 ′ denote lines connecting the weight rotating shaft  32  and the connecting protrusion  36  before and after moving and A 2  denotes angle between the L 2  and L 2 ′. That is, the A 2  denotes rotation angle of the weight  30 . In this case, the lever ratio between the shift lever  20  and the weight  30  is shift lever rotation angle A 1 : weight rotation angle A 2 . 
     In  FIG. 2 , for easy comprehension of the lever ratio of “shift lever rotation angle A 1 : weight rotation angle A”, L 1 ′ and L 2 ′ are identically drawn when the shift lever rotating shaft  22 , the weight rotating shaft  32  and the connecting protrusion  36  are on the same line. 
       FIG. 3  is a drawing showing each stage of rotation operation of an operating shift apparatus for a transmission according to various embodiments of the present invention. 
     As shown in  FIG. 3 , the connecting protrusion  36  may be movable within the guide hole  26  according to rotation of the shift lever  20  and the guide hole  26  is formed for allowing weight  30  to dependently rotate according to rotation of the shift lever  20 . 
     In  FIG. 3 , while exact rotation angle and the rotation ratio are not expressed, however the lever ratio between operation of the operating shift apparatus  10  from (a) to (b) of  FIG. 3  and from (b) to (c) of  FIG. 3  may be different. In detail, when the shift lever  20  rotates anticlockwise direction of the drawing, the lever ratio gradually reduced. That is, the lever ratio is gradually reduced at last phase of the shift operation. The rotational inertia at last stage of the shift operation is reduced comparing the early of the of the shift operation. In the  FIG. 3 , while operation of the operating shift apparatus  10  are expressed as 3 stages for easy comprehension, it is not limited thereto. 
     As described above, according to various embodiments of the present invention, in rotation of a shift lever, relatively small weight may realize relatively large rotational inertia using lever ration of the shift lever and weight. And thus, total weight of the apparatus may be reduced. The lever ratio may be variable according to rotation of the shift lever  20 . The rotational inertia at last stage of the shift operation is reduced comparing the early of the of the shift operation. And thus, impact and noise at last stage of the shift operation may be reduced by gradually reducing rotational inertia. 
     The foregoing descriptions of specific exemplary embodiments of the present invention have been presented for purposes of illustration and description. They are not intended to be exhaustive or to limit the invention to the precise forms disclosed, and obviously many modifications and variations are possible in light of the above teachings. The exemplary embodiments were chosen and described in order to explain certain principles of the invention and their practical application, to thereby enable others skilled in the art to make and utilize various exemplary embodiments of the present invention, as well as various alternatives and modifications thereof. It is intended that the scope of the invention be defined by the Claims appended hereto and their equivalents.

Technology Classification (CPC): 5