Deadman brake assembly for cargo vehicles

• US 5,350,036 A
• Filed: 06/08/1992
• Issued: 09/27/1994
• Est. Priority Date: 06/12/1991
• Status: Expired due to Fees

• Current Assignee: Kabushiki Kaisha Toyoda Jidoshokki Seisakusho
• Original Assignee: Kabushiki Kaisha Toyoda Jidoshokki Seisakusho
• Inventors: Shima, Hideaki
• Primary Examiner(s): Focarino, Margaret A.
• Assistant Examiner(s): DICKSON, PAUL N
• Application Number:
  US07/895,100
• Time in Patent Office: 841 Days
• Field of Search: 180/273, 180/275, 188/109, 267/171, 303/19
• US Class Current: 180/273
• CPC Class Codes: B60N 2/38 specially constructed for use on tractors or like off-road vehicles
• CPC Class Codes: B60T 1/062 acting on transmission parts
• CPC Class Codes: B60T 7/12 for automatic initiation; for initiation not subject to will of driver or passenger limiting speed of vehicles other than rail vehicles B60K31/00

Abstract

A deadman brake assembly incorporating a turnover spring in a link mechanism thereof to exert a spring force in a direction in which a seat supporting plate is kept in a state it enters when a driver sits on the driver'"'"'s seat and to exert the spring force in another direction in which the seat supporting plate is lifted when the driver leaves the driver'"'"'s seat, suppressing as much as possible the lifting force acting on the driver'"'"'s seat when the driver sits thereon.

Claims

1. A deadman brake assembly for a cargo vehicle having a vehicle frame and a driver'"'"'s seat, comprising a brake device for selectively applying a braking force to said cargo vehicle, moving means provided for moving said brake device between a brake release position in response to a driver sitting on said driver'"'"'s seat and a normal brake application position when a driver is not on said seat;

a link mechanism interconnecting said moving means and said brake device for effecting movement of said brake device between said brake release and brake application positions in response to movement of said moving means;

first urging means connected to said link mechanism normally urging said moving means toward said brake application position;

second urging means connected to said link mechanism for urging said moving means toward said brake release position when a driver sits on said driver'"'"'s seat; and

third urging means connected to said link mechanism urging said moving means toward said brake application position independently of said first urging means;

said link mechanism comprising a bell crank having a long arm and a short arm swingably mounted on said vehicle frame by a first mounting means;

said first, second and third urging means being mounted on the end of said long arm by a second mounting means;

one end of said link mechanism being connected in the middle of said long arm;

a brake lever of said brake device being connected to the end of said short arm;

said first urging means comprising a coil spring connected to said vehicle frame on one end thereof and connected to the end of said long arm on the outer end thereof;

said second and third urging means including a turnover spring mounted on said vehicle frame by a third mounting means on one end thereof and connected to the end of said long arm on the other end thereof; and

said third mounting means of said turnover spring being within the swinging range of said bell crank which swings from a first position to a second position as said moving means moves from said brake application position to said brake release position.

2. A deadman brake assembly according to claim 1, wherein said turnover spring is a compression coil spring.

3. A deadman brake assembly according to claim 2, wherein the center of said third mounting means is in a position which is on a line connecting a point substantially in the middle of a locus of points that the center of said second mounting means of said bell crank describes when said bell crank swings from said first position to said second position and the center of said first mounting means of said bell crank, and such that said compression coil spring is maximally compressed when said second mounting means is one said middle point.

4. A deadman brake assembly according to claim 3, wherein component forces, in directions tangential to said locus of points, of an urging force exerted by said turnover spring on said second mounting means act in a direction in which said bell crank is urged toward said first position when the center of said second mounting means is between said middle point and a point corresponding to said first position of said bell crank, and act in a direction in which said bell crank is urged toward said second position when the center of said second mounting means is between said middle point and a point corresponding to said second position of said bell crank.

5. A deadman brake assembly for a cargo vehicle having a frame and a driver'"'"'s seat, comprising a brake device for selectively applying a brake force to said cargo vehicle, said brake device being movable between a brake application position and a brake release position;

a seat supporting plate for supporting said driver'"'"'s seat, said plate being tiltably mounted for movement between an upper position thereof when said seat is unoccupied and a lower position thereof in response to a driver sitting in said seat, said upper position corresponding to said brake application position of said brake device and said lower position corresponding to said brake release position of said brake device; and

a link mechanism interconnecting said seat supporting plate and said brake device and comprising a bell crank, a shaft on said frame mounting said bell crank for pivotal movement, said bell crank having a first arm and a second arm movable together during said pivotal movement of said bell crank, a tension spring connected between said bell crank first arm and said frame and urging said bell crank to a first position, said bell crank second arm being connected to said brake device whereby said brake device is in said brake application position when said bell crank is in said first position, link rod means between said driver'"'"'s seat supporting plate and said bell crank whereby said seat is in said upper position when said bell crank is in said first position responsive to said urging of said tension spring and said bell crank is pivoted to a second position responsive to said seat being moved to said lower position, said brake device being in said brake release position when said bell crank is in said second position, and a compression turnover spring having a first end pivotally connected to said frame and a second end connected to said bell crank to exert urging force reinforcing said urging of said tension spring when said bell crank is in said first position and to exert urging force which partially counteracts said urging of said tension spring when said bell crank is pivoted to said second position.

6. A deadman brake assembly according to claim 5, wherein said turnover spring first end is pivotally connected to said frame at a location on an imaginary line extending between said bell crank shaft and a point located at a middle location on an imaginary arc of said pivotal movement of said bell crank between said first and second positions of said first arm.