Abstract:
Disclosed are apparatus for a block and tackle window balance including a terminal clip to be incorporated in single and double hung window assemblies. In one embodiment the terminal clip includes a first end portion defining an opening for passing a terminal end of a cord therethrough, a second end portion disposed remotely from the first end portion, and an intermediate portion including a hook and extending between the first and second end portions.

Description:
RELATED APPLICATION 
     This application incorporates by reference in its entirety and claims priority to U.S. Provisional Patent Application Serial No. 60/314,748 entitled Side Load Balance Cord Terminal Clip filed on Aug. 24, 2001. 
    
    
     TECHNICAL FIELD 
     This invention relates to terminal clips that transfer force from a cord of a block and tackle window balance to a window jamb to hold up a window sash, and, more particularly to a terminal clip that protects the cord from cutting and abrasion during operation of the block and tackle window balance. 
     BACKGROUND INFORMATION 
     Hung window assemblies generally include a window frame, a lower window sash, an upper window sash, a pair of window jambs, two sets of jamb pockets, and at least one window balance device for offsetting the weight of a window sash throughout a range of travel within the window frame. Block and tackle window balance devices use a combination of a spring and pulleys located within a channel to balance the weight of the window sash at any position within the jamb pockets. 
     When installed in a window frame, the block and tackle window balance device is secured to the window sash and is connected to the window jamb via the terminal clip. The terminal clip, which is attached to a cord connecting the pulleys of the block and tackle window balance, is hooked into an opening within the window jamb. In prior art terminal clips, the cord is attached to a bottom portion of the terminal clip (e.g., below a hooked portion of the terminal clip). 
     In some prior art window balance devices, the cord is attached via a knot to the bottom portion of the terminal clip and thus, is exposed as the highest projection point on the terminal clip. A disadvantage of this type of connection between the cord and the terminal clip is that the exposed cord may be cut or frayed by the block and tackle window balance device during normal operation of the block and tackle window balance. In other prior art window balance devices, the cord is crimped to the bottom portion of the terminal clip. A disadvantage of this type of connection between the cord and the terminal clip is that typically the cord pulls out from a crimped connection at a lower pull out force than for a knotted connection. 
     SUMMARY OF THE INVENTION 
     In general, in one aspect, the invention relates to a terminal clip for attaching a block and tackle window balance device to a window jamb. The terminal clip protects a cord of the block and tackle window balance device from cutting and abrasion during operation. In one embodiment, the terminal clip includes a first end portion defining an opening for passing a terminal end of a cord therethrough, a second end portion disposed remotely from the first end portion, and an intermediate portion extending between the first end portion and the second end portion. The intermediate portion includes a hook for attaching the terminal clip to a window frame. 
     In another embodiment, the terminal clip includes a second end portion that includes a bend and defines at least one second end opening for the cord to pass through. In another embodiment, the second end portion defines two second end openings for the cord to pass through. 
     In yet another embodiment, the terminal clip is made from stainless steel. In other embodiments, the terminal clip is formed of unitary construction. In another embodiment, the terminal end of the cord is knotted. In yet another embodiment, the knot is disposed in an aperture that receives the hooked end when the terminal clip is installed in the window. In one embodiment, when the terminal clip is installed in the window frame, the cord is shielded so as not to extend beyond an uppermost extent of the terminal clip. 
     In general, in another aspect, the invention relates to a terminal clip for a balance for a window. The terminal clip includes a first end defining at least two openings for a cord to pass through, and a hooked end disposed remotely from the first end and wherein the cord terminates proximate to the hooked end. In one embodiment, the first end of the terminal clip includes a bend between the at least two openings. In another embodiment, the terminal clip is formed of unitary construction. In yet another embodiment, when the terminal clip is installed in a window, the cord is shielded being disposed so as not to extend beyond an uppermost extent of the terminal clip. 
     In general, in one aspect, the invention relates to a terminal clip for a window. The terminal clip includes a first end and a hooked end disposed remotely therefrom. The hooked end defines an opening for passing a terminal end of a cord therethrough. 
     In one embodiment, the first end of the terminal clip defines at least one opening for the cord to pass through. In another embodiment, the terminal clip is formed of unitary construction. In yet another embodiment, the terminal end of the cord includes a knot. In still yet another embodiment, the knot is disposed in an aperture that receives the hooked end when the terminal clip is installed in the window. In one embodiment, when the terminal clip is installed in a window, the cord is shielded being disposed so as not to extend beyond an uppermost extent of the terminal clip. 
     In general, in another aspect, the invention relates to a block and tackle window balance device for use in single or double hung windows. The block and tackle window balance device includes a channel, a fixed pulley block unit, a translatable pulley block unit, a spring with a first end and a second end, a cord, and a terminal clip. The spring, the translatable pulley block unit, and the fixed pulley block unit are all located within the channel. The first end of the spring and the fixed pulley block unit are fixed at opposite ends of the channel. The cord has a first end and a second end and connects the translatable and fixed pulley block units. The first end of the cord is attached to the translatable pulley block and a second end is attached to the terminal clip. The terminal clip includes a first end and a hooked end disposed remotely from the first end. The hooked end of the terminal clip defines an opening for passing the second end of the cord therethrough. 
     The foregoing and other objects, aspects, features, and advantages of the invention will become more apparent from the following description and from the claims. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     In the drawings, like reference characters generally refer to the same parts throughout the different views. Also, the drawings are not necessarily to scale, emphasis instead generally being placed upon illustrating the principles of the invention. 
     FIG. 1 is a perspective view of a double hung window. 
     FIG. 2A is a perspective view of a block and tackle window balance including a prior art terminal clip. 
     FIG. 2B is another perspective view of the block and tackle window balance of FIG. 2A with one of two side walls of the U-shaped channel removed. 
     FIG. 3 is a perspective rear view of the block and tackle window balance of FIG.  2 A. 
     FIG. 4A is a perspective view of the block and tackle window balance of FIG. 2A within a window jamb. 
     FIG. 4B is a perspective view of a portion of the window jamb labeled A in FIG. 4A including the terminal clip of FIG.  2 A. 
     FIG. 5A is a perspective view of an embodiment of a terminal clip of the invention. 
     FIG. 5B is a perspective view of another embodiment of a terminal clip of the invention. 
     FIG. 5C is a perspective view of another embodiment of a terminal clip of the invention. 
     FIG. 5D is a perspective view of another embodiment of a terminal clip of the invention. 
     FIG. 6A is a perspective view of the terminal clip of FIG. 5A including a portion of a cord. 
     FIG. 6B is a perspective view of the terminal clip of FIG. 5B including a portion of a cord. 
     FIG. 6C is a perspective view of the terminal clip of FIG. 5C including a portion of a cord. 
     FIG. 6D is a perspective view of the terminal clip of FIG. 5D including a portion of a cord. 
     FIG. 7 is a perspective view of an embodiment of a block and tackle window balance including the terminal clip of FIG.  5 A. 
     FIG. 8 is a perspective view of an embodiment of a block and tackle window balance including the terminal clip of FIG.  5 D. 
     FIG. 9 is a perspective view of an embodiment of a block and tackle window balance of the invention mounted within a window jamb. 
     FIG. 10 is a perspective view of a portion of the window jamb labeled B in FIG. 9 including the terminal clip of FIG.  5 A. 
    
    
     DETAILED DESCRIPTION 
     Referring to FIG. 1, shown is a double hung window assembly  100  in which a block and tackle window balance including a terminal clip constructed in accordance with the teachings of the present invention can be used. The double hung window assembly  100  includes a window frame  102 , a lower window sash  104 , an upper window sash  106 , and a pair of window jambs  107 . Within each window jamb  107 , jamb pockets  108  are defined. The lower window sash  104  and upper window sash  106  slide vertically within the jamb pockets  108 . Generally, window balances are attached to the lower and upper window sashes  104 ,  106  to balance the weight of the window sashes at any vertical position within the jamb pockets  108 . 
     FIGS. 2A,  2 B, and  3  show perspective views of a block and tackle window balance  200  including a prior art terminal clip  245 . FIG. 2A shows the block and tackle window balance  200  in full, whereas FIG. 2B shows the block and tackle window balance  200  with one side wall of a rigid U-shaped channel  205  cut away so that components within the window balance  200  are more visible. FIG. 3 shows a rear view of the window balance  200 . 
     The block and tackle window balance  200  includes a spring  220 , a translatable pulley unit  230 , a fixed pulley unit  235 , a roller  239 , and a cord  240  all housed with the rigid U-shaped channel  205 . Attached to the two ends of the rigid U-shaped channel  205  with fasteners  212 ,  216  are a top guide  210  and a bottom guide  215  that are used to connect the window balance  200  to either the upper or lower window sashes  104 ,  106  and to help guide the vertical motion of the window balance  200  within the jamb pockets  108 . The bottom guide  215  includes a back portion  213 , best seen in FIG. 3, that encases a portion of the rigid U-shaped channel  205 . Within the back portion  213  of the bottom guide  215  is a channel  214  sized to receive a portion of a window sash. 
     The rigid U-shaped channel  205  has a back wall  206  and two side walls  207 ,  208  that in combination form the U-shape. The rigid U-shaped channel  205  serves as an external frame to which the components of the window balance  200  can be secured. The rigid U-shaped channel  205  also keeps components located within the rigid U-shaped channel  205  free of debris and particulate matter. The spring  220 , the translatable pulley unit  230 , the fixed pulley unit  235 , and the roller  239  are located inside the rigid U-shaped channel  205 . Both of the translatable pulley unit  230  and the fixed pulley unit  235  include one or more pulleys rotatable around respective axles. 
     Components within the rigid U-shaped channel  205  work in combination to create a force to counterbalance the weight of the attached sash at any vertical position within the window frame  102 . These components are attached to each other such that a first end  219  of the spring  220  is connected to the translatable pulley unit  230 , and the translatable pulley unit  230  is connected to the fixed pulley unit  235  and the roller  239  via the cord  240 . A pulley in the fixed pulley unit  235  and the roller  239  may be contained in a frame  236 . To secure the components within the rigid U-shaped channel  205 , the second end  221  of the spring  220  and the frame  236  are fixed to opposite ends of the rigid U-shaped channel  205  via respective fasteners  218 ,  243 . The frame  236  is also used to secure a pulley axle  237  and a roller axle  238 , around which the pulley in the fixed pulley unit  235  and the roller  239  respectively rotate. The spring  220  and the translatable pulley unit  230  are connected together by hooking the first end  219  of the spring  220  through an upper slot opening  229  in a frame  225 . The frame  225  houses the translatable pulley unit  230  and a pulley axle  232  around which a pulley in the translatable pulley unit  230  rotates. The cord  240 , which can be a rope, string, or cable, has a first end  241  and a second end  242 . The first end  241  of the cord  240  is secured to the frame  225  and the second end  242 , which is a free cord end, is threaded through the translatable pulley unit  230 , the fixed pulley unit  235 , and the roller  239 , thereby connecting all three components together. After the cord  240  connects the three components together, the prior art terminal clip  245  is secured to the second end (terminal end)  242  of the cord  240 . When the block and tackle window balance  200  is located in the jamb pocket  108 , the prior art terminal clip  245  engages an aperture  430  (FIG. 4A) and the second end  242  sits within aperture  435  of one of the jamb pockets  108 . 
     Once installed within the window assembly, the block and tackle window balance  200  is connected to both the window jamb  107  and to either the lower window sash  104  or the upper window sash  106 . Referring to FIG. 4A, the block and tackle window balance  200  is attached to the window jamb  107  via the prior art terminal clip  245 . The prior art terminal clip  245  is secured within aperture  430  within the jamb pocket  108 , as shown in FIG.  4 B. The second end  242  of the cord  240  which is knotted fits within aperture  435  such that the prior art terminal clip  245  is substantially flush with the window jamb  107 . One example of the prior art terminal clip  245  including cord  240  has a thickness of about 0.120 inches to about 0.140 inches in a direction labeled W,  500  from the window jamb  107 . The block and tackle window balance  200  is then connected to a window sash by inserting a portion of the window sash into the channel  314  of the bottom guide  315  and connecting the top of the window sash to the top guide  310 . 
     FIGS. 5A-5D and  6 A- 6 D show embodiments of terminal clips  345 ,  445  in accordance with the teachings of the present invention. Terminal clips  345 ,  445  transfer force from a cord of a block and tackle window balance to a window jamb to hold up a window sash, while protecting the cord from cutting and abrasion during operation of the block and tackle window balance. Referring to FIG. 5A the terminal clip  345  includes a first end portion  350 , a second end portion  360 , and an intermediate portion  365 . The first end portion  350  defines an opening  352  for passing a second (terminal) end  342  of a cord  340  through, as shown in FIG.  6 A. To secure the cord  340  to the terminal clip  345 , the second end  342  is knotted proximate to opening  352  above intermediate portion  365 . The terminal clip  345  may be made of unitary construction, for example, cut and formed from a single piece of material. In some embodiments, the terminal clip  345  is formed from stainless steel. 
     The cord  340  may be further secured to the terminal clip  345  by including additional openings in the second end portion  360 . For example, as shown in FIGS. 5B and 6B, the second end portion  360  includes an opening  370  for the cord  340  to pass through prior to being knotted proximate to opening  352  above the intermediate portion  365 . As depicted in FIG. 6B, the cord  340  extends longitudinally from the first end portion  350  to and beyond the second end portion  360 . In another embodiment of the terminal clip  345 , shown in FIGS. 5C and 6C, the second end portion  360  includes two openings  370 ,  374  for the cord to pass through and a bend  372  that protects the cord from being cut or frayed by components of the block and tackle window balance  300 , such as, for example the spring  320 . When the cord  340  passes through opening  370 ,  374  and  352 , the cord extends longitudinally from the first end portion  350  to and beyond the second end portion  360 . 
     FIGS. 5D and 6D show another embodiment of a terminal clip  445  in accordance with the teachings of the present invention. Terminal clip  445  includes a first end  460  and a hooked end  465 . The hooked end defines an opening  467  for the cord  340  to pass through. The second end  342  of the cord is knotted after passing through opening  467  to secure the cord  340  to the terminal clip  445 . The first end  460  of the terminal clip  445  can include one or more openings  470  for the cord to pass through prior to being knotted above opening  467 . In addition, the first end  460  may include a bend (not shown) similar to bend  372  of terminal clip  345  shown in FIGS. 5C and 6C. 
     As shown in FIGS. 7 and 8, a block and tackle window balance  300  in accordance with the teachings of the present invention includes a rigid U-shaped channel  305 , a top guide  310 , a bottom guide  315 , a spring  320 , a translatable pulley unit  330 , a fixed pulley unit  335 , a roller  339 , the cord  340 , and one terminal clip  345 ,  445 . (FIG. 7 includes terminal clip  345 , whereas FIG. 8 includes terminal clip  445 ). The top guide  310  and the bottom guide  315  are fixed to the rigid U-shaped channel  305  by fasteners  312 ,  316 . The top guide  310  is used to help connect the block and tackle window balance  300  to the window sash  104 ,  106  and to help guide the movement of the block and tackle window balance  300  within the jamb pocket  108 . The bottom guide  315  is also used for connection and guidance purposes. A back portion  313  of the bottom guide  315  may include a channel  314  for receiving a portion of the window sash, as depicted in FIG.  9 . 
     To install the block and tackle window balance  300  within a window frame  102 , the terminal clip  345 ,  445  is attached to the window jamb  107 . The intermediate portion  365  or the hooked portion  465  is inserted and secured within aperture  430  of the window jamb  107 , as depicted in FIGS. 9 and 10. Because the second end  342  of the cord  340  forms a knot above the intermediate portion  365  (or the hooked portion  465 ) the second end  342  of the cord  340  is also inserted into aperture  430 . Accordingly, there is no need for a second separate opening to be formed within window jamb  107 . Thus, one of the advantages of terminal clips  345 ,  445  of the present invention over prior art terminal clips  245  is that the window frame  102  requires less processing because both the intermediate portion  365  (or hooked portion  465 ) and the knotted second end  342  fit within aperture  430 . As such, a manufacturer of the window frame  102  needs to cut only one aperture  430  in the windowjamb  107  instead of two apertures  430 ,  435  as required by the prior art terminal clip  245  shown in FIG.  4 B. The additional aperture  435  may cause additional air infiltration and may lead to weakening the window frame  102 . Thus, it is advantageous to have fewer apertures cut within the window jamb  107 . 
     Another advantage of the terminal clips  345 ,  445  is cord  340  protection during operation of the block and tackle window balance  300 . If a cord and/or a terminal clip of a block and tackle window balance extends too great a distance (e.g., beyond about 0.120 inches) in the direction labeled W,  500  shown in FIG. 9 from the window jamb  107 , the cord may be cut or damaged by the components within the block and tackle window balance. Additionally, a terminal clip that extends out further than about 0.120 inches, for example, in the W direction,  500  may interfere with the vertical motion of the block and tackle window balance within jamb pockets  108 . Typically, prior art terminal clips  245  have a thickness of about 0.120 inches to about 0.140 inches in the W direction,  500 . Also, due to the connection between the prior art terminal clips  245  and the cord  240 , the highest projection point in the W-direction,  500  is the cord  240 , as shown in FIG.  4 B. Thus, prior art terminal clips  245  expose the cord  240  to possible damage by the block and tackle window balance  200 . 
     Alternatively, terminal clips  345 ,  445  constructed in accordance to the teachings of the present invention are designed such that the maximum thickness in the W-direction,  500  is about 0.100 inches, thereby preventing both the cord  340  and the terminal clip  345 ,  445  from interfering during operation of the block and tackle window balance  300 . To provide additional cord  340  protection, the terminal clips  345 ,  445  may include a bend  372 , as shown in FIG. 10, that projects out a greater distance in the W-direction  500  than the cord  340 . As such, the bend  372  defines an uppermost extent of the terminal clip  345  and shields the cord  340  from being cut or frayed during operation of the block and tackle window balance  300 . 
     Variations, modifications, and other implementations of what is described herein will occur to those of ordinary skill in the art without departing from the spirit and the scope of the invention as claimed. Accordingly, the invention is to be defined not by the preceding illustrative description but instead by the spirit and scope of the following claims.