Spring fastener with highly improved lever/angle pulling force

Abstract

A spring fastener engages the rib of a first part, such as a plastic panel for example, like a pillar for example, may be engaged, and they are also suitable to be engaged reversibly in a slot of second part, such as a metal sheet for example, like the frame of a car for example. The spring fastener comprises engagement springs having a peak, engagement regions and-side cuts in the vicinity of the peak, for example within the engagement regions. The side-cuts, of preferably triangular shape, increase the lever/angle pulling force (pulling force applied on the first part and away from the spring fastener, in order to separate the first part from a second part connected together with the spring fastener). According to one embodiment, the fastener comprises barbs with inwardly bent front ends, and the engagement regions further have hindrance portions.

1 . A fastener comprising: 
 a first side;    a second side opposite the first side, the first side connected to the second side thereby forming a U-shaped structure;    a bottom portion wherein the first side and the second side are connected;    a first engagement spring connected to the first side in the vicinity of the bottom portion; and    a second engagement spring connected to the second side in the vicinity of the bottom portion;    wherein at least one of: the first engagement spring and the second engagement spring comprises side-cuts being across each other.    
   
   
       2 . A spring fastener as defined in  claim 1 , wherein the engagement region further comprises one structure selected from at least one: depression ripple, side rib, upward solid bent extension parallel to the peak, knurled region, bent teeth, each having a depth, a bump, and a combination thereof.  
   
   
       3 . A spring fastener as defined in  claim 1 , wherein at least one of the side-cuts has a triangular shape.  
   
   
       4 . A spring fastener as defined in  claim 1 , wherein each side-cut further includes an upper edge and a lower edge partially bent outwardly.  
   
   
       5 . A spring fastener as defined in  claim 1 , further comprising first barbs and second barbs being cut portions of the respective first and second side.  
   
   
       6 . A spring fastener as defined in  claim 1 , wherein at least one of the side cuts are aligned with a peak on at least one of the engagement springs.  
   
   
       7 . A spring fastener as defined in  claim 1 , wherein at least one of the side cuts includes an upper edge and a lower edge connecting with a spring side of the corresponding engagement spring.  
   
   
       8 . A spring fastener as defined in  claim 1 , wherein the spring fastener further comprises an elastic body molded on the spring fastener.  
   
   
       9 . An assembly of a first part comprising a rib and a spring fastener, the spring fastener comprising 
 a first side; 
 a second side opposite the first side, the first side connected to the second side thereby forming a U-shaped structure;  
 a bottom portion wherein the first side and the second side are connected;  
 a first engagement spring connected to the first side in the vicinity of the bottom portion; and  
 a second engagement spring connected to the second side in the vicinity of the bottom portion;  
   wherein at least one of: the first engagement spring and the second engagement spring comprises side-cuts being across each other.    
   
   
       10 . A spring fastener as defined in  claim 9 , wherein the engagement region further comprises one structure selected from at least one: depression ripple, side rib, upward solid bent extension parallel to the peak, knurled region, bent teeth, each having a depth, a bump, and a combination thereof.  
   
   
       11 . A spring fastener as defined in  claim 9 , wherein at least one of the side-cuts has a triangular shape.  
   
   
       12 . A spring fastener as defined in  claim 9 , further comprising first barbs and second barbs being cut portions of the respective first and second side.  
   
   
       13 . A spring fastener as defined in  claim 9 , wherein at least one of the side cuts are aligned with a peak on at least one of the engagement springs.  
   
   
       14 . A spring fastener as defined in  claim 9 , wherein at least one of the side cuts includes an upper edge and a lower edge connecting with a spring side of the corresponding engagement spring.  
   
   
       15 . A spring fastener as defined in  claim 9 , wherein the spring fastener further comprises an elastic body molded on the spring fastener.  
   
   
       16 . A vehicle comprising parts connected with a spring fastener, the spring fastener comprising: 
 a first side; 
 a second side opposite the first side, the first side connected to the second side thereby forming a U-shaped structure;  
 a bottom portion wherein the first side and the second side are connected;  
 a first engagement spring connected to the first side in the vicinity of the bottom portion; and  
 a second engagement spring connected to the second side in the vicinity of the bottom portion;  
   wherein at least one of: the first engagement spring and the second engagement spring comprises side-cuts being across each other.    
   
   
       17 . A spring fastener as defined in  claim 16 , wherein the engagement region further comprises one structure selected from at least one: depression ripple, side rib, upward solid bent extension parallel to the peak, knurled region, bent teeth, each having a depth, a bump, and a combination thereof.  
   
   
       18 . A spring fastener as defined in  claim 16 , wherein at least one of the side-cuts has at a triangular shape.  
   
   
       19 . A spring fastener as defined in  claim 16 , wherein at least one of the side cuts are aligned with a peak on at least one of the engagement springs.  
   
   
       20 . A spring fastener as defined in  claim 16 , wherein at least one of the side cuts includes an upper edge and a lower edge connecting with a spring side of the corresponding engagement spring.