Abstract:
An agitator mechanism for a clothes finishing cabinet provides a pendulum mounted hanger bar that may reciprocate under the application of a periodic force by an actuator without rigid connection between the cabinet housing and the hanger bar. Quiet operation is obtained by mounting an actuator motor directly on the hanger bar to be isolated by sound absorbing hanger support materials.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS  
       STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT  
       BACKGROUND OF THE INVENTION  
         [0001]    This invention relates generally to machines for removing wrinkles from clothing and in particular to an improved agitator for such devices.  
           [0002]    It has been suggested that wrinkles may be removed from clothing by gentle agitation of drying clothes as they hang on hangers. For example, U.S. Pat. No. 3,739,496 describes a finisher in which clothes are suspended on hangers held by a bar within the cabinet. The bar shaken from side to side while moistened or drying air is blown around the clothes. The combined action of the air flow and agitation of the garments removes the wrinkles with relatively little hand labor.  
           [0003]    The agitation of the clothes may be performed by means of a motor driven crank connected by a crank arm to the bar holding the hangers. A similar crank mechanism for driving a hanger bar is described in U.S. Pat. No. 3,861,179.  
           [0004]    Complete removal of wrinkles from clothing using this technique may require an hour or more to complete. It is therefore desirable that the agitation mechanism be quiet, energy efficient and long-lived. It is further desirable that the force of agitation be limited in the event of an obstruction of the reciprocating mechanism. It is also desirable that the agitation be smooth, reducing unnecessary shifting of and wear to the garments.  
           [0005]    While the crank and crank arm of the prior art is relatively simple, it is not ideal in these other respects.  
         BRIEF SUMMARY OF THE INVENTION  
         [0006]    The present invention provides an agitator that makes use of a natural resonance of the hanger bar to moderate agitating motion. The hanger bar is loosely supported to move freely in at least one dimension at the resonant frequency. In this way, the mass of the hanger bar and the clothes transform periodic force by an actuator into smooth sinusoidal motion. Force is applied to the hanger bar by a compliant elastic cord or other mechanism that may accommodate the hanger bar&#39;s natural resonant motion.  
           [0007]    By eliminating the rigid crank drive mechanism of the prior art, noise transmission is decreased and the force of agitation is limited improving safety and decreasing clothes wear. A smaller motor may be used and energy saved because stalling of the motor under high loads is of less concern. The wear and friction associated with a crank arm linkage is eliminated.  
           [0008]    Specifically, the present invention provides an agitator mechanism for use in a garment finisher of a type having a cabinet in which clothes supported on clothes hangers are shaken to remove wrinkles from the clothes. The agitator mechanism includes a hanger bar for holding at least one clothes hanger pendant therefrom and center biasing supports attached between the hanger arm and the cabinet to bias the hanger bar toward a center position so that when displaced from the center position and released, the hanger bar reciprocates at a natural frequency about that center position. An actuator provides a periodic force on the hanger bar near the natural frequency to cause reciprocation of the hanger bar.  
           [0009]    Thus, it is one object of the invention to provide an extremely simple mechanism for producing smooth, near sinusoidal motion, decreasing noise harmonics and providing a gentle agitation of clothing.  
           [0010]    The center biasing supports holding the hanger bar may be pendulum arms having lower ends attached to the hanger bar and upper ends attached to the cabinet allowing the hanger bar to swing therefrom at a natural frequency equal to the pendulum frequency.  
           [0011]    Thus, it is another object of the invention to provide a reciprocation that is to a first order independent of the amount of weight of clothing hung on the hanger bar. Following the normal rules of a pendulum, the frequency of the reciprocation will be determined by the pendulum arm length not the mass of the clothes.  
           [0012]    The pendulum arms may be an elastomeric material and may be mounted so as to flex slightly with reciprocation of the hanger bar.  
           [0013]    It is another object of the invention therefore to dissipate some energy from the pendulum at high amplitudes to control the amplitude of the motion.  
           [0014]    The hanger bar may include at least one outrigger extending perpendicular to a direction of reciprocation of the hanger bar and at least one of the pendulum arms may attach to an outrigger so that the pendulum arm provides at least three points of attachment to the hanger arm defining a plane.  
           [0015]    Thus, it is another object of the invention to provide a simple mechanism for stably supporting the hanger bar to move predominately in one reciprocation direction.  
           [0016]    The actuator may be a motor mounted on the hanger bar receiving power through flexible leads. The pendulum arms may be sound dampening.  
           [0017]    It is thus another object of the invention to reduce sound transmitted to the cabinet and hence to outside the cabinet by placing the motor on the hanger bar isolated by the sound dampening of the pendulum arms.  
           [0018]    The motor may be substantially centered on the hanger bar and the motor may fit within a cover attached to the cabinet having an aperture for passing the hanger bar through the cover.  
           [0019]    It is thus another object of the invention for the balanced application of force to the hanger bar without direct access to the motor.  
           [0020]    The actuator may be a motor positioned on either the hanger bar or the cabinet with an elastic linkage extending between the motor and the other of the hanger bar and the cabinet.  
           [0021]    Thus, it is another object of the invention to provide a mechanism that naturally limits force and the conduction of sound between the cabinet and the hanger bar.  
           [0022]    The force provided by the hanger bar may be a predetermined amount allowing the hanger bar to be stopped by hand without the stopping of the actuator.  
           [0023]    It is another object of the invention to provide a mechanism that limits damage or motor over heating caused by jamming or obstruction of the hanger bar.  
           [0024]    The foregoing objects and advantages may not apply to all embodiments of the inventions and are not intended to define the scope of the invention, for which purpose claims are provided. In the following description, reference is made to the accompanying drawings, which form a part hereof, and in which there is shown by way of illustration, a preferred embodiment of the invention. Such embodiment also does not define the scope of the invention and reference must be made therefore to the claims for this purpose. 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0025]    [0025]FIG. 1 is a perspective view of the agitation mechanism of the present invention showing a hanger bar suspended by pendulum arms to gently reciprocate pendant hangers, and showing a motor attached directly to the hanger arm and used to provide an exciting force to the hanger arm by means of an elastic strap;  
         [0026]    [0026]FIG. 2 is schematic diagram in elevation of the mechanism of FIG. 1 showing the pendulum motion of the hanger bar under the application of a periodic exciting force;  
         [0027]    [0027]FIG. 3 is a fragmentary perspective view of the pendulum arms of FIG. 1 such as may be constructed from a sound absorbing or elastomeric material to provide sound absorption and/or over travel damping of the pendulum motion;  
         [0028]    [0028]FIG. 4 is a cross-sectional view along lines  4 - 4  of FIG. 1 showing engagement of the hanger with dual holes in the hanger bar to prevent rotation of the hangers about a vertical axis;  
         [0029]    [0029]FIG. 5 is a fragmentary perspective view of a cover fitting over the motor of FIG. 1 and providing illumination of the clothes in the cabinet. 
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT  
       [0030]    Referring now to FIG. 1, the agitator mechanism  10  of the present invention may be fit within a cabinet (not shown) having sidewalls  12  and a ceiling  14 .  
         [0031]    The agitator mechanism  10  includes a horizontally disposed hanger bar  16  suspended from beneath the ceiling  14  of the cabinet on pendulum arms  18  to reciprocate in a lateral direction  20 . The hanger bar is generally horizontal and includes holes  22  for receiving the hook end of hangers  24  which may hang below the hanger bar  16 .  
         [0032]    At ends of the hanger bar  16  near sidewalls  12 , the hanger bar includes transversely extending outriggers  26 . The lower ends of pendulum arms  18  are attached to the transverse extreme ends of the outriggers  26  so that the points of attachment define a plane, preventing twisting of the hanger bar  16  about the lateral direction  20 .  
         [0033]    Referring now to FIGS. 1 and 3, the upper ends of pendulum arms  18  are attached to hook brackets  28  that in turn are attached the ceiling  14 . Pendulum arms  18  may be “dog bone” shaped, having two transversely separated holes  30  in corresponding lobes  32  in the upper end of the pendulum arm  18  and to transversely separated holes  34  in corresponding lobes  32  in the lower end of the pendulum arm  18 .  
         [0034]    The holes  34  in the lower end of the pendulum arm  18  may be attached to corresponding studs in the outriggers  26  and retained by compression of the elastomeric material around the holes  34  acting on expanded heads on the studs  36  when pushed through the holes  34 . In contrast, the holes  30  in the upper end of the pendulum arm  18  are oversized to be received by hooks  40  hanging from a bracket  28 .  
         [0035]    The body of the pendulum arm  18  in horizontal cross-section has a greater transverse dimension  42  than longitudinal dimension  44  and this, in combination of the transverse orientation of the holes  30  and  34  provide that pendulum arms  18  preferentially allow motion along lateral direction  20  and resist other modes of reciprocation.  
         [0036]    Referring now to FIG. 2, it will be understood that the hanger bar  16  and pendulum arms  18  together form a pendulum having a natural period of reciprocation dependent as a first order only on the length of the pendulum arms  18 . Accordingly, different weights and amounts of clothing on hangers  24  may be supported from the pendulum arm  18  without substantially upsetting the frequency of the oscillation. The ability of the hangers  24  to swing in the holes  22  further decouples the hangers from the hanger bar  16 . More generally, the hanger bar  16  may be mounted in any center-biased arrangement, for example, using springs or the like so that resonant excitation will cause it to reciprocate. Such mass-spring systems, however, do not have the advantage of the pendulum system in being indifferent to the weight of the garments.  
         [0037]    Referring still to FIG. 2, each of the pendulum arms  18  provides for pendulum motion of its lower end about its upper end attached to the ceiling  14  of the cabinet. This causes reciprocation in lateral direction  20  of the hangers  24  and the clothes  46  such as draws wrinkles out of the clothes  46  and improves circulation of air and moisture between the clothes  46 . Normally the pendulum motion will die out, however, a periodic force  50  applied to the hanger bar  16  may sustain that motion.  
         [0038]    At extreme points of travel  52  of the pendulum arms  18 , a flexure will occur in the pendulum arm  18 ′ caused by its rigid mounting to the outriggers  26 . This flexing takes energy from the hanger bar  16  thus controlling its amplitude of motion and making the amount of force  50  required for continued oscillation less sensitive.  
         [0039]    Referring now to FIG. 1, one embodiment the periodic exciting force  50  may be applied to the hanger bar  16  by a motor  54  mounted at the center of the hanger bar  16 . The motor  54  may include an eccentric or crank disk  56  attached to rotate around a motor shaft with a crank point  58  eccentric thereto. The crank point  58  may be tied through elastic cord  60  to one or both opposing sidewalls  12 . By mounting the motor on the hanger arm, the direct path of sound conduction to the cabinet is thereby eliminated with the elastomeric material of the pendulum arms  18  and the elastic cord  60  serving to damp out the conduction of motor noise to the cabinet.  
         [0040]    Equally important, a rigid connection between the hanger bar  16  and the cabinet side walls  12  is eliminated, decoupling motion of the hanger bar  16  from the motion of the motor allowing the resonance of the hanger bar  16  to smooth the reciprocating action. Other mechanisms for applying a force without limiting freedom of motion include, for example, jets of air or pulsating magnetic attraction or the like. The profile over time of the applied force is not critical because the natural resonance of the hanger bar  16  tends to convert it to a sinusoidal motion. Sinusoidal motion reduces harmonic noise and limits the forces applied to the clothes. Nevertheless, in the preferred embodiment, the profile of the force is desirably near sinusoidal and of a frequency near the natural resonant frequency of the hanger bar  16  as loaded with clothing and the motor  54 . The pendulum arms  18  may be freely adjusted in length to control the desired frequency of operation of the reciprocation.  
         [0041]    Referring now to FIGS. 1 and 5, by mounting the motor  54  in a central location on the hanger bar  16 , access on either side of the motor may be had for hangers  24  and the loading of the hanger bar  16  may be evenly distributed reducing any tendency of the hanger bar to reciprocate off the lateral axis  20 . A cover  64  may be placed over the motor  54  and attached to the ceiling  14  (or to an upper cover) and to the rear wall  70  of the cabinet to fully enclose the mechanism of the motor  54 . The coupling between the motor  54  and the side walls  12  of the cabinet is force limited by the elastic cord  60  and thus the hanger bar  16  protruding from the cover  64  may be stopped by hand and high forces are not generated in the event of jamming of the hanger bar  16  or catching of clothing or the like. Adjustment of the force may be by adjustment of the spring constant (i.e., thickness) of the elastic cord  60  and the eccentricity of the crank disk  56 .  
         [0042]    The cover  64  may include courtesy lamps  66  for lighting the inside of the cabinet when the cabinet door is open. A cabinet door switch (not shown) controlling the courtesy lamps  66  may serve as an interlock for the motor  54 .  
         [0043]    Flexible leads  65  may connect the motor  54  to a connector  68  on the rear wall  70  of the cabinet and may be covered by the cover  64 .  
         [0044]    Referring now to FIG. 4, the hanger bar  16  may include two vertically extending rails  17  so as to provide transversely spaced apart holes  22 A and  22 B such as engage the hanger  24  to prevent rotation of the hanger  24  about a vertical axis such as might cause rubbing of the clothing or oscillation of the hangers out of the lateral direction  20 .  
         [0045]    It is specifically intended that the present invention not be limited to the embodiments and illustrations contained herein, but that modified forms of those embodiments including portions of the embodiments and combinations of elements of different embodiments also be included as come within the scope of the following claims.