Accelerator pedal assembly for controlling the power of an internal combustion engine

An accelerator pedal, for controlling the power of an internal combustion engine, has a pedal lever which is acted on manually by force on an outer end region, and is swingably mounted on an inner end region around a swing shaft within a bearing housing. The inner end region of the pedal lever extends through an opening into the bearing housing, and is located on the shaft. The bearing housing is developed in two or more parts. The ends of the shaft are arranged on different ones of the housing parts to provide a jam-free mounting of the pedal lever. A spring-load brake contacts the inner region of the pedal lever within the housing.

FIELD AND BACKGROUND OF THE INVENTION 
The present invention relates to an accelerator pedal assembly for 
controlling the power of an internal combustion engine, the lever of which 
pedal can be acted on by manual force at the region of its one end, and is 
mounted for swinging around a swivel axis at the region of its other end. 
Accelerator pedals are known in which the swingably mounted end region of 
the pedal lever is arranged in a bearing bracket, fixed against rotation 
on a shaft the ends of which are rotatably supported in a flanged sleeve. 
Pedal levers of plastic furthermore have a metal tube between the shaft 
and the pedal lever in order to create an attachment which is reliably 
fixed against rotation. A wiper of a potentiometer can be swingably driven 
via the shaft, the potentiometer and wiper being arranged in a separate 
chamber which can be closed by a cover. A lever which acts on a friction 
brake is swingably mounted on an additional shaft which is arranged on the 
bearing bracket. 
Such accelerator pedal assemblies are of complicated construction and 
require a large expenditure for parts and assembly. After the assembling 
of the accelerator pedal, the shaft must be pressed into the pedal lever, 
while the arrangement of the potentiometer on the shaft in a separate 
chamber requires a large amount of space. 
Since the flanged sleeves for the supporting of the shaft are contained in 
the bearing bracket, there is the danger, in the case of a plastic bearing 
bracket, that the pedal lever will get jammed due to elastic deformations 
of the bearing bracket. 
SUMMARY OF THE INVENTION 
It is an object of the invention to create an accelerator pedal of the 
aforementioned type in which an easily movable, jam-free supporting of a 
pedal lever is obtained at a favorable cost in a space-saving manner and 
with only a small number of simple parts as well as a small expense for 
mounting. 
According to the invention, the swingably mounted end region (28) of the 
pedal lever (2) extends through an opening (17) into a bearing housing and 
is arranged on a shaft (1), the bearing housing being developed in several 
parts, and the ends of the shaft (1) being arranged on different housing 
parts. 
The arrangement of the swingably mounted end region of the pedal lever 
within the multipartite bearing housing has the advantage of a 
space-saving construction, the swingably mounted end region of the pedal 
lever together with the shaft being adapted to be mounted in simple manner 
within the bearing housing by a bringing together of the different housing 
parts. 
In this connection, the bearing place of the pedal lever is formed between 
the swingably supported end region of the pedal lever and the shaft, as a 
result of which a rotatable mounting of the ends of the shaft is dispensed 
with and thus, particularly in the case of an elastically deformable 
bearing housing, an easily moving, jam-free mounting is assured. 
The bearing housing may advantageously be developed in two parts and 
consist of a cup-shaped housing part (3) and a cover part (4). 
This has the advantage that upon a mounting of the accelerator pedal, the 
swingably supported end region of the pedal lever and the shaft can be 
introduced through the open end of the cup-shaped housing part and, after 
fixing in position by a placing of the cover part on the housing part, can 
be brought into the assembled position. 
In this case, one end of the shaft is arranged on the bottom of the housing 
part (3) and the other end on the cover part (4). 
It is particularly advantageous if each end of the shaft (1) is arranged in 
a recess (5, 6) in the housing parts. In this case, the shaft is 
dependably fixed in position if the recesses in the housing parts have 
correspondingly suitable tolerances with respect to the ends of the shaft. 
The shaft (1) is arranged fixed against rotation in the manner that the 
ends of the shaft are connected, preferably by form lock, to the housing 
parts. In this way, undesired radial or axial movements of the shaft and 
thus disturbing relative movements between the shaft and the pedal lever 
which lead to a jamming are avoided. 
The shaft (1) is arranged fixed against rotation by form lock on the 
bearing housing. 
The shaft (1) is advantageously arranged fixed against rotation by a 
steplike stop (7) on at least one housing part. This stop makes possible, 
in an easy manner and at a low manufacturing expense, a form-locked 
attachment which can also be loosened rapidly in case of need. 
The shaft (1) extends parallel to a fixed attachment plane of the bearing 
housing, whereby a suitable actuating of the pedal lever is assured. 
The swingably mounted end region (28) of the pedal lever (2) is arranged 
swingable on the shaft (1). This has the advantage that the supporting of 
the pedal lever is effected reliably and jam-free despite elastic 
deformations of the bearing housing, since the shaft is arranged fixed 
against rotation within the bearing housing and the arrangement of the 
pedal lever on the shaft forms a closed bearing place. 
The swingably supported end region (28) of the pedal lever (2) has a recess 
(8) within which a bearing bushing (9) for the supporting of the shaft (1) 
is arranged, fixed against rotation. 
The arrangement of the bearing bushing assures a sliding support of the 
swingably mounted end region of the pedal lever on the shaft, in which 
connection the material of the bearing bushing has good sliding 
properties. 
The swingably mounted end region of the pedal lever (2) has a small amount 
of axial play with respect to the housing parts. 
Due to the stopped arrangement of the shaft within the bearing housing, the 
ends of the shaft are also fixed in axial direction, so that the axial 
play of the swingably mounted end region of the pedal lever with respect 
to the housing parts is controllable and can be reduced to a minimum. 
The regions of the housing parts which receive the ends of the shaft (1) 
have ring-shaped portions (10, 11) which are directed towards each other. 
This has the advantage that, on the one hand, recesses in the housing parts 
assure a dependable reception of the ends of the shaft with respect to 
stability and, on the other hand, further parts which are to be arranged 
within the bearing housing can be received by these ring-shaped portions. 
Thus, a wiper path of a potentiometer can be arranged, fixed against 
rotation, on one of the ring-shaped portions (10, 11) in the regions of 
the housing parts which receive the ends of the shaft. 
On the swingably mounted end region of the pedal lever (2) and 
advantageously, in a recess (12) in said end region, a wiper (14) of the 
potentiometer is arranged, fixed against rotation. 
By the arrangement of the potentiometer within the bearing housing a 
considerable amount of structural space is saved. 
The housing part (3) can advisedly be fastened to the cover part by form 
lock or else detachably by fastening elements, as a result of which the 
accelerator pedal is in the assembled state. 
It is particularly advantageous if the housing part (3) is attached to the 
cover part (4) by a detent engagement (15). 
The bearing housing can be fastened in its fixed attachment plane by 
attachment elements (16) in a region of the housing part (3) and a region 
which connects the housing part (3) with the cover part (4). 
By the fastening in the region connecting the housing part with the cover 
part, the attachment of the housing parts is further stabilized. 
The opening (17) in the bearing housing is advantageously provided with a 
labyrinth-like seal (18) which seals from the swingably mounted end region 
of the pedal lever (2). In this way, the bearing housing is substantially 
closed and protected against dirt and other external influences. 
The swingably mounted end region of the pedal lever (2) is provided with a 
lever arm (19) which is acted on by a return spring (20) which rests on a 
second lever (21) which is swingable around a shaft which is parallel to 
the axis of swing of the pedal lever (2). 
A friction brake (22) can be acted on by the lever (21), the pedal lever 
(2) being swingable against the brake force of the brake. In this 
connection the arrangement of the lever in space-saving manner within the 
bearing housing is advantageous. 
The lever (21) is provided with a depression (23) in which the lever (2) 
can swing around an extension (24) which protrudes from the inner wall of 
the bearing housing. In this way, an additional shaft around which the 
lever is swingable can be dispensed with. 
In order to obtain certain functions, a brake surface (26) which is 
attached fixed against rotation to the pedal lever (2) can be acted on 
with force by a lever arm (25) of the lever (21).

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
FIG. 1 shows a accelerator pedal lever 2 which is mounted at the region 28 
of one of its ends for swinging around a shaft (axle) 1, the pedal lever 2 
extending into a bearing housing 29 consisting of a cup-shaped housing 
part 3 and a cover part 4. 
The pedal lever 2 can be acted on by the force of the foot of the driver on 
a first end region 27 of the lever 2, shown in FIG. 2. 
A first end 30 of the shaft 1 is arranged in form-locking manner in a first 
recess 5 in the bottom of the housing part 3, while its second end 31 is 
arranged in a second recess 6 in the cover part 4. At the recess 5, the 
shaft 1 is fixed against rotation by a steplike stop 7 (FIGS. 1 and 4) 
extending transversely of the shaft 1 in the recess 5. The shaft 1 is 
thereby fixed by the stop 7 in radial and in axial direction to serve as a 
non-rotating axle about which the pedal 2 can pivot. 
For a suitable actuating of the pedal lever 2, the shaft 1 extends parallel 
to a fixed attachment plane 33 of the bearing housing 29. The swingably 
mounted second end region 28 of the pedal lever 2 has a recess 8 in which 
a bearing bushing 9 for the supporting of the shaft 1 is arranged, fixed 
against rotation for swingably mounting the second end region 28 of the 
pedal lever 2 on the shaft 1. 
The regions of the housing part 3 and of the cover part 4 which receive the 
ends of the shaft 1 have ring-shaped portions 10, 11 directed towards each 
other, with respect to which the swingably mounted end region 28 of the 
pedal lever 2 has a slight axial clearance. 
The swingably mounted end region 28 of the pedal lever 2 is advantageously 
provided with a recess 12 within which there is arranged, fixed against 
rotation, a wiper 14 of a potentiometer 32 (FIG. 1) having a wiper track 
13 which is arranged, fixed against rotation, on the ring-shaped portion 
10. 
The housing part 3 is detachably connected to the cover part 4 by a detent 
attachment 15, the bearing housing 29 being adapted to be fastened in its 
fixed attachment plane 33 by attachment elements 16 in a region 34 (FIG. 
1) of the housing part 3 and a region 35 connecting the housing part 3 to 
the cover part 4. As is well known in the construction of a detent, one 
element presses into a slight depression of a second element to produce a 
retention force which retains the two elements in their respective 
positions. To simplify FIG. 1, detent 15 at the bottom of the figure is 
shown without a depression in housing part 3 while, at the top of the 
figure, detent 15 is shown with an exaggerated depression in the housing 
part 3. 
As can be noted from FIG. 2, the swingably mounted end region 28 of the 
pedal lever 2 extends through an opening 17 into the bearing housing 29, 
the opening 17 being provided with a labyrinth-like seal 18, or labyrinth 
packing, sealing off the bearing housing 29 from the swingably mounted end 
region 28 of the pedal lever 2. 
The swingably mounted end region 28 of the pedal lever 2 is provided with a 
lever arm 19 (FIG. 2) which is acted on by a return spring 20 which rests 
on a second lever 21 which is swingable about an extension 24 serving as a 
second shaft or pivot means (FIG. 3) parallel to the axis 37 (FIG. 1) of 
swing of the pedal lever 2. The extension 24 may have any length suitable 
for the swinging of the lever 21, the length in FIG. 1 being shown by way 
of example. 
A friction brake 22 is acted upon by the lever 21, against a braking force 
of which brake the pedal lever 2 is swingable. 
The lever 21 is provided with a depression 23 in which the lever 21 is 
swingable around the extension 24 which extends out from the inner wall of 
the housing part 3. In this way, an additional shaft around which the 
lever 21 is swingable can be dispensed with. 
A brake surface 26 which is connected fixed against rotation to the pedal 
lever 2 can be acted on with force by a lever arm 25 of the lever 21.