Patent Publication Number: US-10787849-B1

Title: Sash balance for vertical slider window

Description:
TECHNICAL FIELD 
     This disclosure is directed to a window balance system and more particularly to a block and tackle balance and shoe assembly for a sliding sash window. 
     BACKGROUND 
     A sash window or hung sash window is made of one or more movable panels, or “sashes,” that form a frame to hold panes of glass, which are often separated from other panes (or “lights”) by glazing bars, also known as muntins. Although any window with this style of glazing is technically a sash, the term is used almost exclusively to refer to windows where the glazed panels are opened by sliding vertically. 
     Modern window assemblies in residential, commercial and industrial buildings may include one or more window sashes that are movable within a window jamb. Window sashes that move vertically to open and close often include two or more window balance assemblies. The balance assemblies urge the window sash upward (i.e., toward an open position for a lower sash or toward a closed position for an upper sash) to assist a user in moving the window sash and to retain the window sash at a position selected by the user. 
     SUMMARY 
     This section provides a general summary of the disclosure, and is not a comprehensive disclosure of its full scope or all its features. 
     The sash balance system disclosed herein is for a sash movable vertically between a pair of window jambs with vertically extending jamb channels disposed within each of the jambs. The system includes a U-shaped balance channel member with a first end and a second oppositely disposed end as well as a shoe for supporting a lower corner of a sash. The shoe is secured to the second end of the U-shaped balance channel and the shoe further includes an upper portion secured to the U-shaped channel and a lower portion extending perpendicular to the U-shaped balance channel. 
     The balance system includes a tension spring disposed within the U-shaped balance channel and the tension spring has a first end and a second end such that the first end is secured in position proximate the first end of the U-shaped channel. The sash balance system also includes a translatable pulley assembly with a carrier member disposed within the U-shaped balance channel, carrier member being secured to the second end of the tension spring. A fixed pulley assembly with a carrier member is also disposed within the U-shaped channel proximate the upper portion of the shoe and a roller is disposed within a channel in the upper portion of the shoe. 
     The sash balance system utilizes a pulley cord with a first end secured to the carrier member of the translatable pulley assembly opposite the connection to the tension spring and the cord also engages the translatable pulley system and the fixed pulley system forming a double tackle configuration and partially encircling the roller before exiting from the shoe. The cord terminates at and is secured to a hook member. 
     The sash balance also includes a jamb guide secured to the first end of the U-shaped channel that lifts the U-shaped channel a de minimis distance from the jamb channel to limit the drag of friction. The lower portion of the shoe also includes spaced apart first and second walls and an open space between the first and second walls. An activator bar with first and second longitudinally disposed ends is positioned within the open space between the first and second lower portion walls. In addition, the activator bar includes first and second longitudinally separated detent nubs that are disposed on a lower surface of the activator bar. The nubs serving as locations to apply manual pressure on the opposite ends of the activator bar to engage or disengage a locking feature comprising an upwardly facing hook. The activator bar further comprises a laterally extending slot proximate the second end of the activator bar and a longitudinally extending bore, the bore terminating at a back wall proximate the first end of the activator bar. 
     The sash balance further includes a compression spring with a first end and a second end disposed within the longitudinally extending bore, the first end of the compression spring is disposed against the bore back wall and a restraining pin extends outwardly from the first lower portion wall, through the activator bar slot thereby restraining the second end of the compression spring and finally into the second lower portion wall. The restraining pin maintains the compression spring in a compressed state in the longitudinally extending bore of the activator bar. 
     The activator bar utilizes a lever arm that extends upwardly and away from the first end of the activator bar terminating at a distal end where a cylinder is transversely mounted. In addition to the activator bar being located within the lower portion, a rocker arm is disposed within the open space between the first and second walls of the lower portion and extends partially into the upper portion of the shoe. The rocker arm is rotatably secured in position by a pin passing through the walls of the upper portion and through a bore hole in the rocker arm. The rocker arm also utilizes an overhanging cutout such that the transverse cylinder of the lever arm slidably engages with the overhanging cutout. 
     As originally detailed above, extending outwardly from the rocker arm is the locking feature, an upwardly facing hook, that is operable between a first and second position. The first position of the activator bar and rocker arm retracts the locking feature while the second position of the activator bar and rocker arm extends the locking feature. 
     In operation the locking feature (hook member) is inserted into an upper most opening in the jamb channel and the cord is withdrawn to an extent sufficient for the locking feature to engage a second opening in the jamb channel thereby securing the balance system in place within each jamb providing a seat for the sash atop the two laterally disposed shoes. 
     An object of the disclosed sash balance is to substantially support the weight of the installed sash. 
     Another object of the disclosed sash balance is to minimize the complexity of the mechanical functioning of the sash balance and to reduce the cost of production of the sash balance. 
     Another object of the disclosed sash balance is to facilitate the ease of installation and removal of the sash from the sash balance system. 
     Another object of the disclosed sash balance is the capability to easily fabricate different sizes of the sash balance to accommodate varying window designs. 
     The contents of this summary section are provided only as a simplified introduction to the disclosure, and are not intended to be used to limit the scope of the appended claims. 
     Various objects, features, aspects and advantages of the disclosed subject matter will become more apparent from the following detailed description of preferred embodiments, along with the accompanying drawings in which like numerals represent like components. The contents of this summary section are provided only as a simplified introduction to the disclosure, and are not intended to be used to limit the scope of the appended claims. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  illustrates a perspective view of a window master frame; 
         FIG. 2A  illustrates a side elevation view of an embodiment of the sash balance disclosed herein; 
         FIG. 2B  illustrates a rear elevation view of an embodiment of the sash balance disclosed herein; 
         FIG. 3  illustrates a front elevation view of an embodiment of a pair of sash balances shown in phantom supporting a sash in a window frame; 
         FIG. 4  is a side elevation view of an embodiment of the sash balance disclosed herein; 
         FIG. 5  is a rear elevation view of an embodiment of the fixed pulley assembly of the sash balance as disclosed herein; 
         FIG. 6A  is a side elevation view of an embodiment of the shoe area of the sash balance disclosed herein with the locking feature fully extended; 
         FIG. 6B  is a side elevation view of an embodiment of the shoe area of the sash balance disclosed herein with the locking feature fully retracted; 
         FIG. 7  is an exploded assembly view of embodiments of the shoe housing, rocker arm, activator bar and compression spring as disclosed herein; 
         FIG. 8  is a perspective view of embodiments of the rocker arm and activator bar as disclosed herein; 
         FIG. 9  is a perspective view of the shoe with the activator bar and rocker arm in hidden lines to identify their orientation within the housing; 
         FIG. 10  is an elevation view of a rear portion of the sash balance illustrating an embodiment of the translatable pulley assembly; 
         FIG. 11  is an elevation view of a rear portion of the sash balance illustrating an embodiment of the fixed pulley assembly; 
         FIG. 12  is an elevation view of a rear portion of the sash balance illustrating an embodiment of the fixed pulley assembly and the pulley cord; 
         FIG. 13A  is a front view of a window frame with embodiments of the two sash balances in initial engagement with the window jamb; 
         FIG. 13B  is front view of a window frame with embodiments of the two sash balances ready for engagement of the locking features into the window jamb; and 
         FIG. 13C  is a front view of a window frame with embodiments of the two sash balances supporting a window sash. 
     
    
    
     DETAILED DESCRIPTION 
     The following description is of various exemplary embodiments only, and is not intended to limit the scope, applicability or configuration of the present disclosure in any way. Rather, the following description is intended to provide a convenient illustration for implementing various embodiments including the best mode. As will become apparent, various changes may be made in the function and arrangement of the elements described in these embodiments without departing from the scope of the appended claims. 
     As seen in  FIG. 1 , disclosed herein is a balance apparatus  10  for mounting in a window frame.  FIG. 1  reveals the standard features of a window including the frame  12  which is the framework that surrounds and supports the entire window system, the head  14  which is the main horizontal part forming the top of the window frame, the jambs  16  which are the main vertical parts forming the sides of a window frame, the sill  18  which is the main horizontal part forming the bottom of the frame of a window, the jambliner  20  which is a strip that is mounted to the sides of a window frame that provides a snug fit for the window sash, the balance  10  which is a mechanical device (generally spring loaded) used in single- and double-hung windows as a means of counterbalancing the weight of the sash during opening and closing the sash  22  which is the moveable part of a window made up of the vertical and horizontal frame that holds the glass, the checkrail  24  which is found on a double-hung window, the part where the bottom part of the upper sash and the upper part of the lower sash come into contact, also known as the middle of the window, and the rail  26  the horizontal piece of a window sash—comprised of the lower  28  and upper  30  rail. 
     A sash balance presently popular is a block and tackle window balance system that include a combination of two or more pulleys, a cord and a spring. The pulleys are grouped as the “block” to reduce the load the homeowner feels when opening and closing a window. In addition, as the cord (or “tackle”) is pulled by the movement of the sash it stretches or reduces the tension on the springs, which are weighted to match the sash weight. The pulleys and springs assist with opening and closing the window thereby reducing the effort required by the person opening or closing the window. 
     The balance apparatus  10  disclosed herein is for a sash  22  movable vertically between a pair of window jambs with vertically extending jamb channels  34  disposed within each of the jambs  16 , the specific operation of the balance apparatus  10  will be detailed later in the operational section of this specification. As seen in  FIGS. 2A and 2B , the balance apparatus  10  includes a U-shaped balance channel member  36  and has a first end  38  and an oppositely disposed second end  40 . The U-shaped channel  36  is preferably fabricated from metal, such as aluminum; however, engineered plastic or even ceramic materials may also be employed. The channel is comprised of two side walls  41 ,  42  and a bottom  44  and preferably of a consistent thickness. The side walls  41 ,  42  are of a sufficient height to provide adequate depth to the channel  36  to allow placement of the hardware  46  that will be described in greater detail below without the hardware extending beyond the upper edges  48 ,  50  of the walls  41 ,  42 . 
     As seen in  FIG. 3 , the balance apparatus  10  includes a shoe  54  for supporting a lower corner  56 ,  58  of a sash  22 . The shoe  54  is secured to the second end  40  of the U-shaped balance channel  36 . The shoe  54  is preferably fabricated from an engineered plastic; however, alternative material options such as metals and ceramics may also be employed. The shoe is also preferably secured to the U-shaped channel with one or more fasteners such as a rivet  55 ; however, alternative means such as adhesives or sonic welding may also be utilized. 
     The balance shoe  54 , as seen in  FIG. 4  includes an upper portion  60  which is secured to the second end  40  of the U-shaped channel  36  and a lower portion  62  that is preferably monolithically molded with the upper portion  60 . The lower portion  62  extends perpendicular to the U-shaped balance channel  36  and employs a platform  64  that extends toward the center of the sash  22  once the sash balance apparatus  10  is installed onto the jamb channels  34 . The upper portion  60  of the shoe  54  is inserted into the second end  40  of the U-shaped balance channel  36  and as seen in  FIG. 5  includes a cutout portion  66  for insertion of additional hardware  68  components as is discussed below in greater detail. 
     The balance shoe  54 , as seen in  FIG. 6A  includes a locking feature  70  in the form of an upwardly facing hook  72  that is selectively operable between: (1) extending laterally outwardly from a rear face  74  of the shoe  54  for engagement with an opening  76  in the jamb channel, and (2) recessed within the shoe  54  as seen in  FIG. 6B . The locking feature  70  is configured for securing the shoe  54  against upward movement when installed within the jamb channel  34 . The locking feature  70  when extended, as shown in  FIG. 6A  includes a gap  80  between the backside  82  of the upward facing hook  72  and the rear face  74  of the shoe  54 . 
     As seen in  FIG. 7 , the shoe  54  in functional form is comprised of four principle separate and interacting components a shoe housing  86 , an activator bar  88 , a compression spring  90 , and a rocker arm  92 . These four principle components and additional restraining features that are discussed below in greater detail, are disposed primarily in the lower portion  62  of the shoe  54  and to a lesser extent in the upper portion  60  of the shoe between spaced apart first and second walls  94 ,  96  in the open space  98  between the first and second walls. The activator bar  88  is disposed within the open space  98  between the first and second lower portion walls  94 ,  96 . The activator bar  88  has first and second longitudinally disposed ends  100 ,  102  and nubs  104 ,  106  that extend downwardly from the oppositely disposed ends of lower surface  108  of the activator bar  88 . The nubs  104 ,  106  serve as manually activated pressure points for deployment and retraction of the hook  72  of the locking feature  70 . The activator bar  88  also includes a slot  110  extending laterally across the activator bar proximate the second end  102  of the activator bar  88 . 
       FIG. 7  further reveals that the activator bar  88  also includes a longitudinally extending bore  112  that originates at the second end  102  and terminates at a back wall  114  proximate, but not actually penetrating through to the first end  100  of the activator bar. The longitudinally extending bore  112  may be formed via a drilling operation or the activator bar  88  may be molded with each half of the molded activator bar incorporating a semi-circular trough such then when the segments are brought together the two troughs form the bore  112 . 
     Also seen in  FIG. 7  is the compression spring  90  with a first end  120  and a second end  122  inserted into the longitudinally extending bore. The first end of the compression spring  120  is disposed against the bore back wall  114 . The second end  122  of the compression spring is restrained in position within the bore  112  by a restraining pin  124  that passes through the slot  110 . When the activator bar  88  is in position within the lower portion  62  of the housing  86  of the shoe  54  the first and second ends  128 ,  130  of the restraining pin  124  are secured to the spaced apart walls  94 ,  96  and spans the open space  98 . The spring  90  provides the force needed to securely position the locking feature  70 , to include the upward facing hook  72 , into either the extended or the retracted positions ( FIGS. 6A and 6B ) depending upon which nub  104 ,  106  is depressed. 
       FIG. 8  reveals that the activator bar  88  also utilizes a lever arm  134  that extends upwardly and away from the first end  100  of the activator bar terminating at a distal end  136 . A cylinder  138  is transversely mounted to the distal end  136  of the lever arm  134 . As previously discussed, the activator bar  88  is disposed within the lower portion  62  of the housing  86  of the shoe  54  and the rocker arm  92  is disposed adjacent the activator bar  88  within the open space  98  between the first and second walls  94 ,  96  of the lower portion  62  and extends partially into the upper portion  60  of the shoe  54 . 
     As seen in  FIG. 9 , the rocker arm  92  is rotatably secured in position by a pin  142  passing through the walls  144 ,  146  of the upper portion  60  and through a bore hole  150  in the rocker arm  92 . The rocker arm has an overhanging cutout  152  that includes saddles  154 ,  156  at the bottom of the cutout  152  and downwardly extending fingers  158 ,  160 . 
     The transversely mounted cylinder  138  atop the lever arm  134  slidably engages with the overhanging cutout  152 . The range of motion of the transversely mounted cylinder is limited to the span of the cutout  152 . The range of motion of the cylinder  138  and lever arm  134  is limited to the span between the seats  164 ,  166  at the top of the cutout  152  and saddles  154 ,  156  at the bottom of the cutout. Moreover, the pin  142  securing the rocker arm  92  in position and the pin  124  securing the activator bar  88  in position prevent the dislocation of the rocker arm  92  and the activator bar  88  from their places of residence within the shoe housing  86 . 
     The compression spring  90  provides the force to drive the lever arm  134  and cylinder  138  into the seats  164 ,  166  at the top of the cutout  152 . When the user manually presses upwardly on the outlying nub  106  this causes the activator bar  88 , lever arm  134  and cylinder  138  to rotate downward with the cylinder  138  resting within the saddles  154 ,  156  at the bottom of the cutout  152 . As the cylinder  138  rotates downward within the cutout  152 , this causes the rocker arm  92  to rotate about the pin  142  that secures the rocker arm  92  in position. The upwardly facing hook  72  is rotated outwardly from the lower portion  62  of the shoe  54  and is in a position ready for engagement with an opening in the jamb channel and to counter the force applied by the spring and pulley system of the balance system. 
     When the operator seeks to withdraw the upwardly facing hook  72  into the shoe  54 , the downwardly facing nub  104  is manually pressed, in an upward direction, which overcomes the resistance exerted by the compression spring  90  and drives the lever arm  134  and cylinder  138  of the activator bar  82  upward within the cutout  152  and into the seats  164 ,  166  at the top of the cutout. This upward movement of the lever arm  134  and cylinder  138  causes a rotation of the rocker arm  92  that retracts the hook  72  back into the shoe housing  86  facilitating vertical movement of the balance system  10  with the installed sash. 
     As seen in  FIG. 10 , the sash balance apparatus also utilizes a tension spring  170  disposed within the U-shaped balance channel  36 . The tension spring  170  includes a first end  172  and a second end  174  wherein the first end  172  is secured in position proximate to the first end of the U-shaped channel  36  with a hook  178 , in a preferred embodiment, secured to a cross bar  180  that spans from the first wall  41  to the second wall  42  of the U-shaped balance channel  36 . The free length, body length, wire diameter, loop length and outside diameter of the tension spring  170  are dictated by the specific load characteristics of the sash to be balanced and the travel of the sash between a closed and fully open position. 
       FIG. 11  reveals an embodiment of a translatable pulley assembly  184  with a carrier member  186  disposed within the U-shaped balance channel  36 . The translatable pulley assembly  184  consists of a pair of pulleys  188 ,  190  separated by the carrier member  186 . An axle  192  passes through the carrier member  186  and the two pulleys  188 ,  190  are mounted to the axle  192 , one on each side of the carrier member  186 . The carrier member  186  is preferably a thin metal plate that includes an opening  194  at a first end  196  through which the second end  174  of the tension spring  170  is secured by a second spring hook  200 . A translatable pulley guide  202  is also optionally utilized to maintain the pair of pulleys  188 ,  190  centered within the U-shaped balance channel  36  during translation within the channel. 
     As seen in  FIGS. 11 and 12 , the counterbalance to the tension spring  170  secured through the opening  194  at the first end  196  of the carrier member  186  is a load  204  applied at the second end  206  of the carrier member  186 . The load  204  is maintained with the use of a first end  208  of a pulley cord  210 . The pulley cord  210  extends within the U-shaped channel  36 , as seen in  FIG. 12 , to a fixed pulley assembly  212  that is disposed superjacent to the cutout portion  66  of the shoe  54 . The fixed pulley assembly  212  is comprised of two pulleys  214 ,  216 , preferably similar in dimension in all respects to the two pulleys  188 ,  190  of the translatable pulley assembly  184 . The two pulleys are separated by a fixed pulley assembly carrier member  220 . This carrier member  220  also includes an axle  222  passing through an opening  224  near the first end  226  of the carrier  220   
     Mounted to the axle  222  on each side of the carrier member  220  are the two pulleys  214 ,  216 . Secured roughly mid-way between the first end  226  and the second end  228  of the carrier member  220  is a single roller  230  riding on an axle  232  that passes through an opening  234  in the carrier member  220 . The second end  228  of fixed pulley assembly carrier member  220  is secured to the shoe housing  86 . The mechanism of attachment of the carrier member  220  to the shoe housing  86  is preferably a pin  236  passing through an opening  238  in both sides  240 ,  242  of the shoe housing as well as an opening  244  proximate the second end  228  of the fixed pulley assembly carrier member  220 . The rigid nature of the material of the first and second sidewalls  41 ,  42  of the U-shaped channel  36  prevents movement of the pin  236  and restrains the carrier member  220  in position. 
     As previously detailed, the first end  208  of the pulley cord  210  is secured to the second end  206  of the carrier member  186 . The pulley cord  210  then traverses to the fixed pulley assembly  212  and reverses direction after passing around the second pulley  216 . The cord then traverses back to the second pulley  190  of the translatable pulley assembly  184 . After passing around the second pulley  190 , the cord traverses to the first pulley  214  of the fixed pulley assembly  212 . After wrapping one-half of the circumference of the first pulley  214 , the cord reverses direction again and traverses within the U-shaped channel member  36  returning to the translatable pulley assembly  184  and wraps around one-half of the circumference of the first pulley  188 . 
     After partially wrapping the first pulley  188  the cord traverses again within the U-shaped channel member  36  in the direction of the fixed pulley assembly  212 . The pulley cord  210  traverses beneath the roller  230  and exits at the rear face  74  (See  FIG. 6A ) of the shoe  54 . The second end  246  of the pulley cord  210  is secured to a hook  248  that in operation is secured to openings in the jambliner  20 . The presence of the hook  248  prevents the cord from being withdrawn into the cutout portion of the shoe pursuant to the force applied by the spring  170 . A faceplate  249 , or similar type hardware, prevents retraction of the hook  248  due to the hook  248  being too large to pass through the faceplate  249 . The pulley cord  210  is; however, capable of passing through the faceplate. 
     In operation, as seen in  FIGS. 13A-13C , a pair of sash balances  10  are sequentially installed in the jambs  16  of a window frame  12 . These sash balances  10 , as seen in  FIG. 13C  are used to support the underside  250  of a sash  22  positioned between the jambs  16  in a window frame  12 . The installation and removal procedure is the same for both the left and right sash balances so a generic discussion of the process is set forth below. When installing the sash balance  10  onto the jambliner  20  the upwardly facing hook  72  of the locking feature  70  must be in the outwardly extended position. To place the upwardly facing hook into the outwardly extended position, the user applies manual pressure to the outermost nub  106  as best seen in  FIGS. 6A and 6B . 
     This manually applied pressure causes one end  102  of the activator bar  88  to rotate upward within the lower portion  62  of the shoe  54  and the second end  100  to rotate downward. As the activator bar  88  rotates, the lever arm  134  connected to the activator bar  88  and the cylinder  138  connected at the distal end of the lever arm  134  rotate downward. As the cylinder  138  which resides transversely in the overhanging cutout  152  slides downward it engages with the saddles  154 ,  156  in the cutout causing the rocker arm  92  to rotate about the pin  142 . Once the cylinder  138  presses against the saddles  154 ,  156 , the rocker arm  92  begins to rotate about the restraining pin  142 . 
     As the rocker arm  92  rotates, the upwardly facing hook  72  extends outwardly from the rear face  74  of the shoe  54  revealing the gap  80  between the backside  82  of the upward facing hook  72  and the rear face  84  of the shoe  54 . The rocker arm  92  and activator bar  88  remain static in their new positions, i.e., with the hook extended, because of pressure applied by the compression spring  90  housed within the bore  112  of the activator bar  88 . The compression spring  90  causes the lever arm  134  and cylinder  138  to apply pressure to the saddles  154 ,  156  in the cutout and to maintain the rocker arm  92  in the position with the upwardly facing hook  72  outwardly extended until the operator applies manual pressure to the first nub  104  overcoming the force applied by the compression spring  90 . 
     With the retractable hook  72  extended, the user approaches the window frame  12  and engages the hook  248  at the second end  246  of the pulley cord  210  into an opening  254  in the top of the jambliner  20 . The user then positions the sash balance guide  52  into the track  21  of the jambliner  20 . The sash balance guide  52 , as seen in  FIGS. 2A and 2B , facilitates the movement of the sash balance in the jambliner  20  and slightly offsets the first end  38  of the U-shaped channel member  36  from the floor of the jambliner track  21 . The slight offset distance D minimizes the area of surface contact between the U-shaped channel member  36  and the jambliner  20  thereby reducing the friction between the two surfaces. The sash balance guide  52  is preferably fabricated from an engineered plastic; however, alternative materials such as metal and ceramics would also be functional. 
     The user then applies manual downward pressure causing the pulley cord  210  to be withdrawn from the sash balance  10 . The pulley cord  210  which terminates at the hook  248  and begins at the carrier member for the translatable pulley  186  is essentially inelastic such that when the hook  248  is extracted an immediate reaction occurs at the translatable pulley  186 . The pulley configuration disclosed herein is a double tackle. 
     In a double tackle configuration, a single continuous cord  210  is used to transmit a tension force around the four pulleys, i.e.,  188 ,  190 ,  214 ,  216  to move a load, in this case the load developed by the tension spring  170 . The mechanical advantage of the block and tackle in the configuration disclosed herein is four (4), thus the block and tackle reduces the force required to extend the tension spring  170  by a factor of four (4). At the same time, the velocity ratio of the tackle is 4:1. In other words, to extend the tension spring  170  at a rate of 1 inch/second, the hook  248  must be retracted at a rate of 4 inches/second; however, the force necessary to extract the hook is only 25% of the load being applied to the carrier member  186  of the translatable pulley assembly  184 . 
     As the user retracts the hook  248  from the sash balance  10 , the double block and tackle system is engaged and the force necessary to extend the tension spring  170  is effectively only one-fourth of the load being applied by the spring itself. As the hook  248  is withdrawn and the sash balance is lowered into position the upwardly facing hook  72  is positioned within an opening  256  in the window jambliner  20 . Once both sash balances  10  are installed into the jambs  16  of the window frame  12  the sash  22  may be installed within the window frame and ultimately atop the platforms  64 . To install the sash  22 , the sash is slightly rotated about a midline vertical axis and positioned superjacent the first sash balance platform  64 . The first sash stile  23 A is then pressed firmly into the jamb  16 . The sash  22  is then rotated the opposite direction from the original rotation about the midline vertical axis and the second sash stile  23 B is positioned within the opposing jamb  16  and superjacent the second sash balance platform  64 . Next, the sash  22  is lowered into position atop the two shoe platforms  64 . 
     Once the sash  22  is supported by the two sash balance platforms  64  the user slightly drops the sash  22  and presses the outermost nub  104  which causes the activator bar  82  to rotate upward driving the lever arm  134  and cylinder upward in the overhanging cutout  152  until the cylinder reaches the seats  164 ,  166  at the top of the cutout  152 . Once the seats  164 ,  166  are impacted, the force applied to the seats causes the rocker arm  92  to rotate about the pin  142  and to retract the upwardly facing hook  70 . 
     Once the two hooks  70  are retracted, the sash  22  is free to translate within the jambliner  20  and may be slid freely up and down with much of the weight of the sash being counterbalanced by the spring force of the sash balance  10 . With much of the weight of the sash being counteracted by the sash balance spring force the level of effort required by the user to reposition the sash is reduced and sash movement requires less effort on the part of the user. 
     To remove the sash  22  using the system disclosed herein, the user lowers the hook  72  to below the opening  256  in the window jambliner. Once the hook  72  is below the opening  256 , the user presses the inner most nub  106  on each shoe  54  and then proceeds to raise the sash balance and sash combination. Upon achieving the same elevation as the opening  256 , the hook  72  will engage with the opening  256  and upward movement of the sash balance  10  will be halted. Once the sash balances  10  are locked into position the user applies a manual force to the sash  22  causing it to move laterally to one side. Once the sash  22  is displaced to one side the sash is rotated about the sash stile  23 A or  23 B on that same side and the sash stile on the opposite side may then be extracted from the frame  12 . Once the first sash stile  23 B is rotated out of the window frame the second sash stile  23 A can readily be extracted. 
     Having shown and described various embodiments of the present invention, further adaptations of the methods and systems described herein may be accomplished by appropriate modifications by one of ordinary skill in the art without departing from the scope of the present invention. Several of such potential modifications have been mentioned, and others will be apparent to those skilled in the art. For instance, the examples, embodiments, geometries, materials, dimensions, ratios, steps, and the like discussed above are illustrative and are not required. Accordingly, the scope of the present invention should be considered in terms of the following claims and is understood not to be limited to the details of structure and operation shown and described in the specification and drawings. Moreover, the order of the components detailed in the system may be modified without limiting the scope of the disclosure.