Patent Publication Number: US-8978429-B2

Title: Flip key for an automotive vehicle with enhanced resistance to forces exerted onto an insert of such flip key

Description:
The invention relates to a key for access and/or ignition of automotive vehicles, in particular such key comprising an insert and a rotatable bearing supporting the insert so that the insert is rotatable in and out of a housing of the key between an open position and a closed position. 
     Such keys, known as flip keys are advantageous in terms as having a low volume when flipped into the closed position and in terms of being easy to handle manually when in the open position. Indeed, as the housing of such key is aimed at receiving both the insert, a rotating mechanism for the rotation of the insert, and also an electronic equipment for remote unlocking of the vehicle, the housing is usually large in size and hence constitutes a strong and comfortable area for prehension by the end-user. 
     A drawback appears with such keys due to their ability to be strongly handled. Indeed users which are faced with an urgent need for a tool in their every day life, for example for opening a can, spinning a screw, extracting a pin, scratching in any type of cavity, etc. . . . are often prone to using such a key in the role and in replacement of such a needed tool. 
     There results from such situation that flip keys are oftentimes inadvertently damaged, in particular at the level of the rotatable bearing of the insert, which gets no more able to be maintained firmly in its open position for use in a lock of the vehicle. 
     It is an aim of the invention to propose a flip key which is more robust to such undue use of the key as an improvised tool. It is more generally an aim of the invention to propose a key which is more robust to damages in current use and in particular is more robust against damages of the rotation mechanism of the key. 
     These aims are achieved by way of the invention as recited in appended claim  1 . 
    
    
     
       Other features, aims and advantages of the invention will appear throughout the detailed description which is made here-after, made in reference to the appended drawings, among which: 
         FIG. 1  is a partial underneath view of a flip key according to an embodiment of the invention; 
         FIG. 2  is a perspective view of a rotatable bearing for a insert of such same flip key; 
         FIG. 3  is a partial underneath view of a flip key according to the same embodiment, without the rotatable bearing of the insert 
         FIG. 4  is a view of a side view of a push button according to the same embodiment of the invention. 
     
    
    
     The flip key represented on  FIG. 1  comprises an insert  10 , a rotatable bearing  20 , a push button  30  and an upper cover  40  of a housing of the key. 
     The rotatable bearing  20  is mounted with freedom to rotate inside the housing, by means of the push button  30  which here constitutes a rotation shaft for the rotatable bearing  20 . For this purpose, the rotatable bearing  20  comprises a through hole  31  in which the push button  30  extends so that the push button  30  emerges through the upper cover of the housing  40 . A lower cover of the housing which is not represented here comprises a finger which emerges from an internal face of the lower cover so as to emerge inside the push button  30  and hence maintain the push button  30  against any movement along a main plane of upper and lower covers. 
     The push button  30  comprises a cylindrical main body and a series of three radially extending legs  32 ,  33 ,  34  which are engaged in corresponding anchoring cavities having the shape of radial grooves in the rotatable bearing  20 . This way, the push button  30  and the rotatable bearing  20  are fixed each other in mutual rotation. 
     As represented on  FIG. 4 , two legs  32 ,  33 , are located at around half height of button, with a thickness of around one third of the height of the button. Last leg  34  is located at a lower level of the push-button  30 . The push button  30  comprises a free height h above legs  32  and  33 . Such height h corresponds to the thickness of the upper cover  40  of the housing added with a height of a portion of the push button desiredly emerging out of the upper cover  40  of the housing. 
     The rotatable bearing  20  comprises anchoring cavities, in the shape of radial grooves  22 ,  23  and  24  which respectively receive the legs  32 ,  33 ,  34  of the push-button. Theses anchoring grooves  22 ,  23 ,  24  present a thoroughness which is greater than the part of the legs  32 ,  33 ,  34  which is engaged in the rotatable bearing, so that legs  32 ,  33 , and  34  have a freedom to be displaced along the main direction of the push button inside the rotatable bearing  20  without exiting out of the rotatable bearing. 
     The push button  30  is pressed into an idle upper position by means of a helicoidal spring and in this idle position, legs  32  and  33  of the push-button have a part which emerges above an upper face of the rotatable bearing  20 . The upper cover  40  of the housing has an underneath face which comprises a series of radially oriented anchoring cavities having the shape of radial grooves  42   a ,  43   a ,  42   b ,  43   b  for receiving legs  32  and  33 . More specifically, radially oriented anchoring grooves  42   a  and  43   a  are positioned so as to receive the upper emerging part of legs  32 ,  33  when the rotatable bearing is in closed position of the key, while the radially oriented anchoring grooves  42   b  and  43   b  are located so as to receive the upper emerging part of legs  32 ,  33  when the rotatable bearing is in open position of the key. In each one of these positions, legs  32 ,  33  present a lower part which is engaged in a respective anchoring groove  22 ,  23  of the rotatable bearing so that the rotatable bearing is maintained against rotation by means of the legs  32 ,  33  engaged both into the upper cover  40  of the housing and into the rotatable bearing  20 . 
     When the user pushes the button  30 , then the upper emerging part of the legs  32 ,  33  exits from the anchoring grooves  42   a ,  43   a  or  42   b ,  43   b  thereby freeing the rotatable bearing  20  in rotation as the legs  32 ,  33  are then engaged solely in the rotatable bearing  20 . 
     During this process, lower leg  34  slides inside anchoring groove  24  of the rotatable bearing and comes in abutment with the lower cover of the housing, without any contact with the upper cover  40  of the housing. The lower leg  34  hence acts as a lower abutment of the button  30  in a lower slidable position of the button and constitutes a further maintaining element for solidarizing the push-button  30  and the rotatable bearing  20  in rotation and opposing rotation of the button while the other legs  32 ,  33  are engaged in the radially oriented anchoring grooves  42   a ,  43   a  or  42   b ,  43   b  of the upper cover  40  of the housing. 
     In the open situation represented on  FIG. 1 , when the user exerts a force onto the insert  10  which tends to flip the insert towards the closed position thereof, a torque appears onto the rotatable bearing  20 . Due to this torque, each one of legs  32  and  33  is subject to a double and opposite effort from the rotatable bearing  20  and from the upper cover  40  of the housing, resulting in a transversal shear or scissors efforts onto each leg  32 ,  33 . 
     Rotatable bearing  20  is located at a corner of the housing and fills a cavity  50  formed in the housing which is dedicated to rotation of the rotatable bearing. 
     As the rotatable  20  bearing has its center located close to the edges of the housing, the rotatable bearing  20  comprises a restricted edge  25   a  conformed to the corner of the housing. 
     More precisely, the rotatable bearing  20  presents two opposite and centrally symmetrical edges  25   a  and  25   b  which both have the same shape as the corner of the housing, these two opposite edges  25   a  and  25   b  rejoining each other at their extremities so as to form angular extremity corners  26   a  and  26   b . The rotatable bearing hence here resembles like a seashell having an elongated shape. 
     In a main rotating plane of the rotatable bearing, i.e. a plane which is perpendicular to the axis of rotation of the rotatable bearing embodied by the push button, different dimensions of the rotatable bearing can be determined and in particular a couple of directions can be determined comprising a direction a and a direction b in which the rotatable bearing is respectively longer and shorter in such main plane of rotation. In the present example, direction a is defined here as the direction where the rotatable bearing  20  is the longest possible. As a result this direction a corresponds to an axis which crosses opposite extremity angular corners  26   a  and  26   b  where the opposite and equal shapes  25   a  and  25   b  adjoin each other. 
     However, it will be understood in the course of the following description that other such directions which are longer than a complementary transversal direction may be defined on such an elongated shape of the rotatable bearing and that constitute the longer direction of a couple of directions made of a longer and a shorter direction. 
     For example, instead of defining the longer direction a as being the one which crosses the extremity angles  26   a ,  26   b  of the rotatable bearing  20 , the longer direction a may be a direction which is the direction perpendicular to a main longitudinal axis of the housing when the rotatable bearing  20  is in a position corresponding to either the open or the closed position of the key. A longer position a chosen this way is a position in which the longer leg  33  hence becomes perpendicular to the main longitudinal direction of the key when the key is in the open or in the closed position. 
     The present shorter direction b is chosen here so as to be close to perpendicular relative to the longer direction a, more precisely here a bit more spaced than perpendicular relative to direction a as will be described again below. 
     The above described directions a and b are chosen here as the directions in which legs  33  and  32  respectively extend. Leg  32  is extending in a shortest direction of the rotatable bearing and presents a radial length which is quite equivalent to half radius of the cylindrical main body of the push-button  30 . 
     On the contrary, leg  33  extends in a longer direction a of the rotatable bearing and leg  33  is dimensioned here with a longer radial length than the length of leg  32 . This longer length of leg  32  is made possible in the case of leg  33  by the fact that a large amount of constitutive material of the rotatable bearing  20  is present in the area which neighbours the extremity of leg  33  in the rotatable bearing  20 . In the present case, length of leg  33  is high enough so that leg  33  would have is longer than a radial dimension of the rotatable bearing  20  in the shortest direction, so that leg  33  would have emerged laterally from the rotatable bearing  20  if it had been oriented in the direction of the shortest dimension. 
     The anchoring groove  23  which receives the elongated leg  33  in the rotatable bearing  20  presents a length equal to the length of leg  33 . Similarly, the radial anchoring grooves  43   a  and  43   b  which are aimed at receiving the longer leg  33  have the same radial length as the length of leg  33 . 
     The longer leg  33  thus engages both the rotatable bearing  20  and the upper cover  40  of the housing throughout the whole length of longer leg  33 . A particularly strong force of interaction opposing rotation of the rotatable bearing  20  appears due to the fact that the leg  33  interlocks the upper cover  40  and the rotatable bearing  20  on a particularly large area. 
     As depicted on  FIG. 1 , a force F exerted onto the insert  10  is transformed into a force F′ appearing between anchoring groove  23  of the rotatable bearing and leg  33  as well as between leg  33  and anchoring groove  43   b  of the cover  40 . Force F onto the inset also transforms into a force F″ appearing between anchoring groove  22  of the rotatable bearing and leg  32  as well as between leg  32  and radial anchoring groove  42  of the cover  40 . Forces F′ and F″ are repatriated on the whole lengths respectively of leg  33  and leg  32  so as to oppose force F onto the insert  10  and maintain the rotatable bearing against undue rotation. 
     As the length of leg  33  is particularly high, force F′ can reach a particularly high amount before a damage appears at the contact area between leg  33  and rotatable bearing  20  as well as between leg  33  and upper cover  40 . 
     Hence force F can reach a particularly high value before the rotatable bearing  20  begins a rotation in the housing through any damage between housing, button and rotatable bearing. 
     In the present example, the main body of the button is close to 8 mm in diameter, and the longer leg  33  is 3.5 mm in diameter while the shorter leg  32  is 2 mm in diameter. 
     While it is preferred in terms of volume and robustness to adopt a longer leg which is longer around 1.5 mm more than the shorter leg, the longer leg is preferably higher than the length of the shorter leg in a range of 1 mm to 2 mm of length increase between both lengths. With such dimensions, a force F of 150N can be applied onto the insert  10  without any damage on the key components. 
     Of course, one advantage of such a longer leg oriented in a longer direction of the shape of the rotatable bearing  20  and a shorter leg in a transversal direction has been described here in connection to a push button  30  engaging into the upper cover of the housing. However, any other assembly using such a couple of legs comprising a longer leg can be imagined without departing from the invention. 
     In particular, longer leg  33  can be engaged into the lower cover of the housing, the leg  33  and possibly also leg  32  being permanently engaged in a respective anchoring groove of the lower cover while being able to exit underneath of a corresponding anchoring groove of the rotatable bearing when the push button is pressed by the user. In such case, the push button may be a rotationally fixed push button relative to the housing of the key. 
     Longer leg  33  and/or shorter leg  32  may also be permanently engaged in the upper cover  40  of the housing, while another leg is selectively engaged in the push button, able to exit a corresponding anchoring groove of the push button through an underneath area of such push button. Such other leg may also be a longer leg extending in a longer direction of the rotatable bearing as compared to a direction in which extends a shorter leg of such push button