Belt tightening tool

A belt, which passes around a pulley on a shaft of an element movable about a pivotal connection to tighten the belt, is tightened by a tool including a body, which rests on the pivotal element, and a handle pivotally mounted to the body. A flexible band has one end attached to the body and is passed around the pivotal element and through guides on the body prior to being releasably connected to the handle. When the handle is pivoted relative to the body with the flexible band tight around the pivotal element, the pivotal element is moved about its pivotal connection to tighten the belt.

This invention relates to a belt tightening tool and, more particularly, to 
a tool for moving an element, which has a shaft on which a pulley is 
disposed and having a belt passing therearound, about its pivotal 
connection to tighten the belt through moving the pivotal element to a 
position where the belt has the desired tension and the pivotal element is 
retained against movement. 
In motor vehicles, various elements such as a generator, an alternator, a 
power steering pump, or an air conditioner compressor, for example, are 
driven from the internal combustion engine through one or more flexible 
belts. Each of these elements has a pulley mounted on its shaft with the 
belt passing therearound and around a pulley driven from an output shaft 
of the internal combustion engine. 
To replace each of these belts, it is necessary for one of the pulleys to 
be mounted on an element that is movable about a pivotal connection to the 
engine block so as to enable the belt to pass around the pulley thereon as 
well as the pulley on the output shaft of the internal combustion engine 
and then to have the element be pivoted to a position in which the belt is 
tightened and the pivotal element then locked in that position. For 
example, a generator or an alternator may be mounted on the engine block 
by a pivotal connection. The generator or the alternator may be locked in 
position through the generator or the alternator having a bracket mounted 
thereon and cooperating with a mounting bracket, which is fixed to the 
engine block, with one of the two brackets having an arcuate slot therein 
and the other having an opening to enable a bolt to pass through both of 
them and be retained in position by a nut. This locks the generator or the 
alternator in the position in which the belt is sufficiently tightened so 
as to have the desired tension thereon. If the belt is not tightened 
sufficiently, damage may occur to the pivotal element. 
Because of the rather cramped condition within the engine compartment of a 
motor vehicle, it is difficult to tighten the belt to the desired tension. 
Various types of levers for applying a force against the pivotal element 
such as a crowbar, for example, have been used by mechanics to move the 
pivotal element about its pivotal connection to a position in which the 
belt has sufficient tension through being properly tightened, and then 
holding the pivotal element in this position with the crowbar while 
locking the pivotal element in this position. This is a difficult 
operation for one person and is time consuming. 
Various types of tools for exerting forces on portions of an internal 
combustion engine of a motor vehicle are disclosed in U.S. Pat. No. 
1,890,227 to McKee, U.S. Pat. No. 2,656,749 to Johnson, U.S. Pat. No. 
4,145,938 to Laird, Jr., and U.S. Pat. No. 4,249,296 to Colburn. None of 
these patents is directed to tightening a belt passing around pulleys 
through moving a pivotal element having the belt pass around a pulley on 
its shaft. 
The belt tightening tool of the present invention enables a belt, which 
passes around a pulley on a shaft of a pivotal element, to be tightened by 
one person through causing movement of the pivotal element about its 
pivotal connection to the engine block and enabling it to be locked in the 
position to which it is moved. Thus, the belt tightening tool of the 
present invention does not require a crowbar, for example, and eliminates 
the need for a second person to aid in tightening the belt. 
The belt tightening tool of the present invention can be readily utilized 
with any of the pivotal elements in a motor vehicle engine compartment 
having a pulley around which a belt passes. Therefore, the difficulty of 
obtaining a position in which a portion of the crowbar may fulcrum on the 
engine block and exert a force on the pivotal element is avoided by the 
belt tightening tool of the present invention. 
When using a crowbar, for example, the possibility exists that the pivotal 
element or the portion of the engine block against which the crowbar 
fulcrums to move the pivotal element may be damaged by the crowbar. The 
belt tightening tool of the present invention avoids any damage to any 
element in the engine compartment of the motor vehicle while still 
obtaining the desired belt tightening. 
When using a crowbar, for example, the possibility exists that the crowbar 
may slip at either its fulcrum or its end engaging the pivotal element. If 
this occurs, it is possible that the person attempting to tighten the belt 
may be injured. The belt tightening tool of the present invention reduces 
the possibility of danger to the user. 
The belt tightening tool of the present invention includes a flexible band, 
which has one end attached to a body, passing around a pivotal element 
having a pulley around which the belt passes. The flexible band is 
releasably connected to a handle, which is pivotally mounted on the body. 
While the flexible band is positioned as tight as possible around the 
pivotal element, the pivoting of the handle increases the tightening of 
the flexible band around the pivotal element. Thus, an increased force is 
exerted on the pivotal element with this increased tightening of the 
flexible band by pivoting of the handle insuring that the pivotal element 
is moved to the position in which the belt passing around the pulley on 
the pivotal element is tightened to the desired tension. 
An object of this invention is to provide a tool for tightening a fan belt 
or the like. 
Other objects of this invention will be readily perceived from the 
following description, claims, and drawing. 
This invention relates to a tool for tightening a belt passing around a 
pulley on a shaft of a pivotal element. The tool includes a body for 
disposition on the pivotal element and flexible means, which pass around 
the pivotal element, attached to the body. A handle is pivotally mounted 
on the body by pivotally mounting means with the handle having means to 
releasably connect the flexible means to the handle after the flexible 
means has passed around the pivotal element so that pivoting of the handle 
moves the pivotal element to tighten the belt passing around the pulley on 
the shaft of the pivotal element.

Referring to the drawing and particularly FIGS. 1 and 2, there is shown a 
belt tightening tool 10 for tightening a belt 11 passing around a pulley 
12 on a shaft 14 of a pivotal element such as an alternator 15 that is 
movable about a pivot fixed to the engine block of a motor vehicle when 
locking means to lock the alternator 15 to the engine block is released, 
for example. Any other pivotal element, which has a flexible belt like the 
belt 11 passing around a pulley on its shaft, also may have the belt 11 
tightened by the tool 10. 
The tool 10 includes a substantially rectangular shaped body 16, which is a 
hollow square shaped tube, and a U-shaped handle 17 pivotally mounted on 
the body 16. The body 16 has a pair of side walls 18 and 19 (see FIG. 3), 
which are substantially parallel to each other. The upper surfaces or 
edges of the side walls 18 and 19 have a top wall 20 (see FIG. 1) 
extending therebetween. The top wall 20 does not extend for the entire 
length of the body 16. The end of the top wall 20 has a angled portion 21 
extending therefrom to serve as a guide for a band 22 when the handle 17 
is pivoted counterclockwise (as viewed in FIG. 1) beyond the position of 
FIG. 2. 
The band 22, which is formed of any suitable flexible material such as 
cloth webbing, for example, has a loop 23 at one end passing around an 
expansion pin 24, which extends between the side walls 18 and 19 (see FIG. 
2) of the body 16 and into an opening 25 (see FIG. 1) in each of the side 
walls 18 and 19 (see FIG. 2). Washers 26 (see FIG. 3) are disposed 
adjacent the inner surface of each of the side walls 18 and 19 so that the 
band 22 does not rub against either of the side walls 18 and 19. 
Each end of the body 16 has a bumper 27, which is formed of a suitable 
elastomeric material such as rubber, for example, extending downwardly 
beyond its bottom surface or edge, as shown in FIG. 1, for engagement with 
the alternator 15 around which the band 22 is passed. Each of the bumpers 
27 is secured to one end of a substantially flat bottom portion 28 (see 
FIG. 3) of the body 16 by a pair of screws 29. 
The flat bottom portions 28 of the body 16 are formed by cutting an arcuate 
portion 30 (see FIGS. 1 and 2) in each of the side walls 18 and 19 of the 
body 16. This removes most of the bottom portion of tha body 16 to leave 
only the flat bottom portions 28 of the body 16. A plastic arcuate strip 
31 is attached to each of the side walls 18 and 19. 
The body 16 has a guide 34, which is a roller formed of a suitable plastic, 
disposed above one of the flat bottom portions 28 of the body 16 and 
extending between the side walls 18 and 19. The guide 34 extends through 
the side walls 18 and 19 and is supported on an expansion pin 35 extending 
into an opening 36 in each of the side walls 18 (see FIG. 1) and 19 (see 
FIG. 2). The band 22 (see FIG. 1) passes around the top of the guide 34. 
A roller 37 is supported on a bolt 38 so that the band 22 passes underneath 
the roller 37. The bolt 38, which extends through the side walls 18 and 19 
(see FIG. 3), is retained in position by a nut 39 (see FIG. 2). The roller 
37 is disposed so that its leftmost surface in FIG. 1 is in substantially 
vertical alignment with a curved surface 40 at the junction of the angled 
portion 21 and the top wall 20 of the body 16. 
The U-shaped handle 17 has its substantially parallel legs 41 and 42 (see 
FIG. 2) disposed on the outer surfaces of the side walls 18 and 19 (see 
FIG. 3), respectively, of the body 16. The handle 17 (see FIG. 1) is 
pivotally mounted on the body 16 by an expansion pin 43 extending through 
the leg 41 of the handle 17, the side wall 18 of the body 16, the side 
wall 19 (see FIG. 2) of the body 16, and the leg 42 of the handle 17. 
Thus, the pivotal axis of the handle 17 is to the left of the roller 37 in 
FIG. 1 and adjacent thereto. 
The handle 17 has a plastic rod 45 extending between the legs 41 and 42 
(see FIG. 2) and held in position on the handle 17 by an expansion pin 46 
(see FIG. 1) passing through the rod 45 and an opening 47 in each of the 
legs 41 and 42 (see FIG. 2). The rod 45 has a pair of notches 48 (see FIG. 
4) formed in its surface although only one of the notches 48 is used and 
required. Each of the notches 48 defines two spaced portions 49 and 50 of 
the surface of the rod 45 to be engaged by the band 22 when a roller 51 of 
cam means 52 is moved into engagement with the band 22 to hold it against 
the rod 45 as shown in phantom in FIG. 1. This provides two pressure 
points between the rod 45 and the roller 51. 
The roller 51 is eccentrically mounted on the handle 17 (see FIG. 1) by an 
expansion pin 53, which extends between the legs 41 and 42 (see FIG. 2) of 
the handle 17 and into an opening 53' in each of the legs 41 (see FIG. 1) 
and 42 (see FIG. 2). A handle 54 is attached to the roller 51. 
Accordingly, after the band 22 is passed over the rod 45, the roller 51 is 
rotated counterclockwise, as viewed in FIG. 1, about the expansion pin 53 
by the handle 54 until the roller 51 engages the band 22 against the 
spaced portions 49 (see FIG. 4) and 50 of the rod 45. 
With the band 22 releasably connected to the handle 17 (see FIG. 2) by the 
roller 51 holding the band 22 against the spaced portions 49 (see FIG. 3) 
and 50 of the rod 45, the handle 17 (see FIG. 1) is pivoted 
counterclockwise, as viewed in FIG. 1, about the axis of the expansion pin 
43 to tighten the band 22 about the alternator 15. This moves the 
alternator 15 about its pivotal connection to the engine block to tighten 
the belt 11 (see FIG. 2) because of the shaft 14 and the pulley 12 being 
moved away from the fixed pulley on the output shaft of the internal 
combustion engine around which the belt 11 also passes. 
Considering the operation of the present invention, the body 16 of the tool 
10 is positioned on the surface of the alternator 15 with any well-known 
locking means being released so that the alternator 15 can pivot about its 
pivotal connection to the engine block. One suitable example of the 
well-known locking means includes a bolt extending through an arcuate slot 
in one of a bracket on the alternator 15 and a bracket, which is fixed to 
the engine block, and an opening in the other of the brackets with the 
bolt being retained by a nut. 
Then, the band 22 is passed around the alternator 15 and over the guide 34 
and underneath and around the guide roller 37. With the handle 17 in the 
position of FIG. 1 and the roller 51 of the cam means 52 moved away from 
the rod 45, the band 22 is passed over the top of the rod 45. Then, the 
handle 54 moves the roller 51 into engagement with the band 22, as shown 
in phantom in FIG. 1, to hold the band 22 against the spaced portions 49 
(see FIG. 4) and 50 of the rod 45. 
With the band 22 as tight as possible around the alternator 15 (see FIG. 1) 
at the time that the roller 51 engages the band 22 against the spaced 
portions 49 (see FIG. 4) and 50 of the rod 45, pivoting of the handle 17 
from the position of FIG. 1 to the position of FIG. 2 or beyond moves the 
alternator 15 about its pivotal connection to the engine block. This 
shifts the pulley 12 sufficiently relative to the fixed pulley on the 
output shaft of the internal combustion engine to provide the desired 
tension on the belt 11. 
As the handle 17 is being pivoted counterclockwise, as viewed in FIG. 1, 
the band 22 is tightened even further. This increased gripping power 
increases the force applied to the alternator 15 to tighten the belt 11. 
With the belt 11 having the desired tension in it, the alternator 15 is 
retained in this position by the well-known locking means. Next, the 
handle 17 is pivoted from its position in FIG. 2 or beyond to its position 
in FIG. 1 and the roller 51 is rotated clockwise, as viewed in FIG. 1, 
away from engagement with the band 22. Then, the band 22 is pulled away 
from the alternator 15. 
An advantage of this invention is that there is no damage to any movable 
element with which the tool of the present invention is used. Another 
advantage of this invention is that the flexible band is self tightening 
beyond its initial tightening. A further advantage of this invention is 
that it reduces the danger to a person tightening the belt. Still another 
advantage of this invention is that it provides positive gripping of the 
flexible band when it is wrapped around a movable element. 
For purposes of exemplification, a particular embodiment of the invention 
has been shown and described according to the best present understanding 
thereof. However, it will be apparent that changes and modifications in 
the arrangement and construction of the parts thereof may be resorted to 
without departing from the spirit and scope of the invention.