Cable clamping apparatus

An improved cable clamping apparatus is disclosed. The apparatus is adapted for use in a cable actuated power drive mechanism having a cable and a cable drive mechanism. In a preferred embodiment, the improved cable clamping apparatus includes a coupling element for moving a mass in response to the movement of the cable. A particularly novel aspect of the invention is the provision of a cable clamp attached to the coupling element for clamping the cable such that the coupling element moves in response to the movement of the cable. The cable clamp is generally L-shaped with an integral first section and dual U-shaped second sections each adapted to receive the cable therein. In a specific embodiment, the dual U-shaped sections of the clamp are separated to receive and retain a cable collar therebetween. In a further more specific embodiment, at least one U-shaped section of the clamp is adapted for fastening with an appropriate fastener to enclose a portion of the cable therein.

BACKGROUND OF THE INVENTION 
1. Field of the Invention 
The present invention relates to drive mechanisms. More specifically, the 
present invention relates to drive mechanisms for the power windows 
automobiles, trucks and other passenger vehicles. 
While the present invention is described herein with reference to 
illustrative embodiments for particular applications, it should be 
understood that the invention is not limited thereto. Those having 
ordinary skill in the art and access to the teachings provided herein will 
recognize additional modifications, applications, and embodiments within 
the scope thereof and additional fields in which the present invention 
would be of significant utility. 
2. Description of the Related Art 
Many techniques are known in the art for driving a power window of an 
automobile, truck or other passenger vehicle. One such technique involves 
the use of a flexible cable which is wrapped around a power driven spool. 
A coupling element is mounted on a track and clamped to the cable. The 
window sits on the coupling element. When the drive mechanism is 
activated, the cable pulls the coupling element along the track and 
thereby translates the position of the window. 
In some conventional of this scheme, the cable is merely gripped by the 
coupling element. In many cases, the grip of the coupling element on the 
cable may loosen over time. This results in a total failure of the power 
window drive mechanism. 
Accordingly, there is a need in the art for an improved cable-actuated 
power window drive mechanism. More specifically, there is a need in the 
art for an improved cable clamp apparatus for use in such power window 
drive mechanisms. Ideally, the cable clamp apparatus would be suitable for 
retrofitting the cable-actuated power drive mechanisms already in service. 
SUMMARY OF THE INVENTION 
The need in the art is addressed by the improved cable clamping apparatus 
of the present invention. The apparatus is adapted for use in a cable 
actuated power drive mechanism having a cable and a cable drive mechanism. 
In a preferred embodiment, the improved cable clamping apparatus includes 
a coupling element for moving a mass in response to the movement of the 
cable. A particularly novel aspect of the invention is the provision of a 
cable clamp attached to the coupling element for clamping the cable such 
that the coupling element moves in response to the movement of the cable. 
The cable clamp is generally L-shaped with an integral first section and 
dual U-shaped second sections each adapted to receive the cable therein. 
In a specific embodiment, the dual U-shaped sections of the clamp are 
separated to receive and retain a cable collar therebetween. In a further 
more specific embodiment, at least one U-shaped section of the clamp is 
adapted for fastening with an appropriate fastener to enclose a portion of 
the cable therein.

DESCRIPTION OF THE INVENTION 
A cable actuated power drive mechanism 10 is illustrated in FIG. 1. The 
mechanism 10 includes an electrical motor 12 having wires 14. The wires 14 
are typically connected to a source of electrical energy (not shown) via a 
switch (not shown). As is known in the art, the motor 12 drives a spool 16 
(shown in phantom) encased within a housing 18. A cable 20 is connected at 
both ends or wrapped about the spool 16. The spool 16 is capable of 
bi-directional rotation about an axle 22. The cable 20 is fabricated of 
flexible yet strong material such as stranded wire, plastic or other 
suitable material. The cable 20 is protected by rubber hoses 24 and 26. 
The cable 20 is constrained in a loop by a number of guides 28, 30, 32 and 
34. Between a pair of guide rollers 36 and 38 suspended from a frame (not 
shown) via corresponding brackets 40 and 42 respectively, the cable is 
substantially straight and connected to a coupling element 44. The 
coupling element 44 is mounted on a track 46 for translational movement in 
response to the movement of the cable 20. In a power window system, the 
coupling element 44 is attached to a window 50 (shown in phantom) at a 
protrusion 48. A stop 52 extends through the coupling element 44. The stop 
52 is in threaded engagement with the coupling element 44 and is therefore 
adjustable to allow the range of motion of the coupling element 44 to be 
adjusted. The stop 52 may have a rubber or plastic tip as is known in the 
art. The manner in which the coupling element 44 engages the cable 20 is 
the subject of the present invention. 
A conventional coupling element 44' is shown in FIGS. 2 and 3. FIG. 2 shows 
the conventional coupling element 44' seated on a track 46 in operative 
engagement of the cable 20. As shown in FIG. 4, the diameter of the cable 
20 is extended by a an annular metallic collar 21 which extends 
longitudinally over a small portion thereof. The method by which the 
conventional coupling element 44' operates is best illustrated with 
reference to the cross-sectional view of FIG. 3. Note that the element 44' 
has a recess 54' within a lip 57' off the main body 55' thereof which is 
coated with plastic 56' or other suitable lubricating spacing material The 
recess 54' serves to receive the track 46. The spacing material assists in 
the maintenance of the proper orientation of the element 44' relative to 
the track 46. The main body of the coupling element 55' includes a second 
recess 58' which is adapted to receive and grip the cable 20 at the collar 
21 thereof. Unfortunately, as is known in the art, over a period of time, 
the grip of the recess 58' on the collar 21 begins to loosen. When this 
occurs, it often leads to a catastrophic failure of the entire power drive 
mechanism 10. 
FIGS. 5-9 illustrate the preferred embodiment of the cable clamp apparatus 
44 of the present invention which is designed to overcome the above-noted 
problems besetting the coupling element 44' of the related art. FIG. 5 
shows, in a perspective view, the cable clamp apparatus 44 of the present 
invention. It includes a coupling element 45 and a cable clamp 60. The 
coupling element 45 is mounted on a track 46 in operative engagement with 
a cable 20. As shown in the cross-sectional view of FIG. 6, the coupling 
element 45 of the present invention is structurally similar to the 
coupling element 44' of the related art (see FIG. 3). One key difference 
is that the lip 57' of the coupling element 44' of the related art is not 
present in the coupling element 45 of the preferred embodiment. The lip 
57' is removed to allow the cable clamp 60 of the present invention to 
seat on the coupling element 45 and perform the function of the recess 58' 
of the coupling element 44' of the related art. Otherwise, the coupling 
element 45 of the present invention is essentially identical in structure 
and operation to the element 44' of the related art. Hence, the cable 
clamp 60 constitutes a key feature of the present invention. 
FIG. 7 is a side elevational view of the cable clamp 60 of the present 
invention. The cable clamp 60 is made of metal or other suitable material. 
The cable clamp 60 is generally L-shaped with an integral first section 62 
and dual U-shaped second sections 64a and 64b each adapted to receive the 
cable 20 therein. As shown in the top view of FIG. 8, the clamp 60 
includes an aperture 68 in the first section 62 which is of sufficient 
diameter to allow the clamp to seat over the protrusion 48 of the coupling 
element 45. See FIG. 6. In the rear view of FIG. 9, the relationship 
between the dual U-shaped second sections 64a and 64b and the cable 20 
with associated collar 21 may be appreciated. Note the troughs of the 
U-shaped sections 64a and 64b are substantially parallel so that the cable 
20 sits within each. Note, further, that in accordance with the teachings 
of the present invention, the collar 21 on the cable is not gripped as in 
the related art, but, instead, the collar 21 is held between the U-shaped 
sections 64a and 64b. Thus, the ability of the clamp to move the element 
45 in response to the movement of the cable 20 is not dependent on the 
strength of the frictional grip on the collar 21. 
Before returning to FIG. 6, note the provision of openings 66a and 66b in 
the U-shaped sections 64a and 64b respectively. These openings are 
provided to allow screws 68 to retain the clamp 60 in place on the 
coupling element 45. See FIG. 6. 
As illustrated in the cross-sectional side view of FIG. 6, the screws 68 
are effective to (1) hold the clamp in place on the coupling element 45; 
(2) to cooperate with the washers 70 to retain the cable within the 
troughs of the U-shaped sections 64a and 64b; and (3) to act as a fastener 
and vary the extent to which the cable 20 is squeezed by the U-shaped 
sections 64a and 64b. This third feature adds additional security to the 
clamping action provided by the clamp 60 of the present invention and 
ensures against a failure which might otherwise result from a loosening of 
the collar 21 on the cable 20. 
Thus, the present invention has been described herein with reference to a 
particular embodiment for a particular application. Those of ordinary 
skill in the art having access to the teachings provided herein will 
recognize additional modifications, applications, and embodiments within 
the scope thereof. For example, other fastener means may be used other 
than the screws 68 without departing from the scope of the present 
invention. Further, the invention may be used for applications other than 
power windows. 
It is therefore intended by the appended claims to cover any and all such 
applications, modifications, and embodiments. 
Accordingly,