Window balance assembly with improved mounting bracket and curl spring attachment
A window balance assembly includes: a housing with first and second interior spaces; a receiver rotatably supported in the first interior space; a curl spring disposed in the second interior space with a tail extending out of the housing; and a mounting bracket. The tail includes: a neck and a head. The mounting bracket includes first and second flanges. First and second guide members protrude from opposite sides of a rear surface of the first flange, and slidably support the tail proximate to the rear surface. First and second ramp members on the rear surface include an upper recess, and are spaced permitting passage of the neck therebetween. When the tail slides between the second guide members the ramp members force the head away from the rear surface, until the head passes beyond the ramp members. The curl spring biases the head into the recesses.
1 . A window balance assembly comprising:
a housing, said housing defining a first interior space and a second interior space;
a receiver, said receiver being rotatably supported in said first interior space and comprising: a cam;
a curl spring, said curl spring comprising: a first portion disposed within said second interior space and comprising a plurality of convolutions, and a second portion configured to extend outside of said second interior space; wherein said second portion comprises: a neck portion, and an elongated head portion, said elongated head portion being oriented transverse to said neck portion at a distal end of said neck portion;
a mounting bracket, said mounting bracket comprising:
a first flange;
a second flange;
a first guide member configured to protrude from a first side of a rear surface of said first flange;
a second guide member configured to protrude from a second side of said rear surface;
wherein each of said first guide member and said second guide member are configured to slidably receive said second portion of said curl spring and to maintain said second portion of said curl spring in proximity to said rear surface;
a first ramp member configured to protrude from said rear surface of said first flange;
a recess formed in a top of said first ramp member;
a second ramp member configured to protrude from said rear surface of said first flange;
a recess formed in a top of said second ramp member; and
wherein said first ramp member and said second ramp member are spaced apart to form a gap configured to permit passage of said neck portion in said gap; and
wherein said first ramp member and said second ramp member are configured to divert said head portion away from said rear surface, when said second portion of said curl spring slides between said first guide member and said second guide member, in proximity to said rear surface, until said head passes beyond said first ramp member and said second ramp member.
2 . The window balance assembly according to claim 1 , wherein when said head passes beyond said first ramp member and said second ramp member, said curl spring biases a first portion of said head into said first recess and a second portion of said head into said second recess, thereby nesting said neck in said gap.
3 . The window balance assembly according to claim 2 ,
wherein said housing comprises: a first elongated tab and a second elongated tab; and
wherein said cam is configured to outwardly deflect a distal end of each of said first elongated tab and said second elongated tab when said receiver is rotated from a first position to a second position.
4 . The window balance assembly according to claim 3 , wherein said neck of said curl spring comprises: a joggle, said joggle positioned at a distal end of said neck, and said joggle configured to offset said elongated head portion a distance away from said neck portion.
5 . The window balance assembly according to claim 4 , wherein said second portion of said curl spring is formed to be substantially flat.
6 . The window balance assembly according to claim 5 , wherein a length of said head is greater than a width of said neck.
7 . The window balance assembly according to claim 6 , wherein a width of said neck is about half of a width of said first portion of said curl spring.
8 . The window balance assembly according to claim 7 , wherein a distance between outer sides of each of said first ramp member and said second ramp member is greater than said length of said head portion.
9 . The window balance assembly according to claim 8 , wherein said second flange is at a ninety-degree angle to said first flange.
10 . The window balance assembly according to claim 9 , wherein said second flange comprises: a first aperture and a second aperture, each of said first aperture and said second aperture having an axis being at a non-ninety-degree angle to said second flange.
11 . The window balance assembly according to claim 10 ,
wherein said housing comprises: a first cantilever member and a second cantilever member; and
wherein when said receiver is rotated from a first position to a second position, said cam drives each of said first cantilever member and said second cantilever from a first portion to a second position to thereby protrude outwardly.
12 . A window balance assembly comprising:
a housing;
a receiver, said receiver being rotatably supported in said housing;
a curl spring; said curl spring comprising: a plurality of convolutions, with a first end of said curl spring disposed within said plurality of convolutions; and a second of said curl spring comprising: a neck portion, and an elongated head portion, said elongated head portion being oriented transverse to said neck portion;
a mounting bracket, said mounting bracket comprising:
a first flange;
a second flange;
a first guide member configured to protrude from a first side of a rear surface of said first flange;
a second guide member configured to protrude from a second side of said rear surface;
wherein each of said first guide member and said second guide member are configured to slidably guide a portion of said curl spring and to maintain said portion of said curl spring in proximity to said rear surface;
a first ramp member configured to protrude from said rear surface of said first flange;
a recess formed in a top of said first ramp member;
a second ramp member configured to protrude from said rear surface of said first flange;
a recess formed in a top of said second ramp member; and
wherein said first ramp member and said second ramp member are spaced apart to form a gap configured to permit passage of said neck portion in said gap; and
wherein said first ramp member and said second ramp member are configured to divert said head portion away from said rear surface, when said portion of said curl spring slides between said first guide member and said second guide member, in proximity to said rear surface, until said head passes beyond said first ramp member and said second ramp member.