Abstract:
A locking mechanism disposed on one of the panels of foldable doors utilized in railway cars for transporting vehicles for automatically connecting the panels together when in a collapsed position.

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The field of invention relates to folding door assemblies utilized in transportation vehicles, particularly to locking mechanisms for keeping the collapsed door panels together. 
     2. Description of Prior Art 
     U.S. Pat. No. 786,569 discloses a locking mechanism for folding doors having a combination of a jamb-locking lever and a door-coupling lever mounted upon one door of a pair of folding doors coacting with the studs mounted on a jamb and two doors. 
     U.S. Pat. Nos. 1,849,801 and 3,107,722 disclose a swinging hook engaging with a stud or a structural member of a hatch cover. A latching mechanism for holding the multi-leaf doors open having an H-shaped latching bar with one of the legs pivotally housed in a clamp and another leg being received in a T-shaped slot in a bracket was shown in U.S. Pat. No. 3,416,836. 
     U.S. Pat. No. 3,996,860 discloses a gravity hook engaged with a keeper welded on the crank to prevent folded door panels from swinging. 
     Also, gravity hooks engaging with a keeper plate or spring-loaded plunger catch for holding bi-fold doors in collapsed position were patented in U.S. Pat. No. 4,164,189. 
     The prior art fails to disclose a novel locking mechanism described in the subject invention. 
     SUMMARY OF THE INVENTION 
     The present invention of an improved locking device comprises a housing attached to the inside face of a first panel of a bi-fold door assembly and a spring-loaded lever disposed in the housing for disengaging the lock between collapsed panels. As soon as the outside face of the first panel contacts the same of the second panel the locking mechanism automatically couples both panels. A keeper end portion of the lever engaging with the keeper member on the outer panel may be manually disengaged by pivotal movement of the lever, the outer portion whereof is easily accessible when the panels are folded. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a rear elevational view showing the end of a railway car with doors in unfolded position; 
     FIG. 2 is a cross-sectional view taken substantially along the lines 2--2 of FIG. 1 showing the partial opening of the folding door arrangement; 
     FIG. 3 is a side elevational view of a locking mechanism; 
     FIG. 4 is a cross-sectional view taken substantially along the lines 4--4 of FIG. 3; 
     FIG. 5 is an exploded perspective view of a locking mechanism. 
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENT 
     A locking device for automatic coupling of the panels of bi-fold or foldable door assemblies utilized in transportation vehicles which comprises a hat-shaped housing 1 having an intermediate flange 2 and two oppositely extending flanges 3. The housing 1 is mechanically attached to the inside surface of a first panel 4. A central portion of the intermediate flange 2 has a center opening 5. An angle-shaped lever 6 has a vertical outer portion 7 and a horizontal portion 8 extending inwardly therefrom through said opening 5 inside the housing 1. The horizontal portion 8 has a keeper engaging end portion 9. A compression spring 10 is disposed in the housing 1. The spring 10 urges the end portion 9 to a locked position with a keeper member 11 disposed on the outer panel 12. The outer panel 12 has an opening 13 in registry with the latch engaging end portion 9 of the lever 6 to provide an access of the lever 6 to the keeper member 11 on the outer panel 12 when both panels, first and second, are folded together. The first panel 4 has an opening 14 in registry with the housing opening 5 and outer panel opening 13 to facilitate engagement of the keeper engaging end portion 9 with the keeper member 11 on the second panel 12. A cotter pin 15 projecting through the housing 1 is engageable with a bushing 16 attached to the horizontal portion 8 of the lever 6 to provide rotation of said lever horizontal portion 8 about its vertical axis on said housing 1. A locking device as described above facilitates automatic coupling of the panels of the doors utilized in transportation vehicles and allows easy disengagement by a slight pivotal movement of the lever which is located outside of the main area of activities at the end of the vehicle and is hidden inside the care when the folding panels of the door assembly are in the closed position. When the doors are collapsed and kept in the stored position the lever is located on the side parallel to the side walls of the vehicle free of any interference with the loading and unloading process at the end of the vehicle.