Measuring and testing – Test stand – For engine
Reexamination Certificate
2003-02-28
2004-10-12
McCall, Eric S. (Department: 2855)
Measuring and testing
Test stand
For engine
C073S118040
Reexamination Certificate
active
06802207
ABSTRACT:
BACKGROUND OF THE INVENTION
The present invention relates to rotational driving apparatuses for testing internal combustion engines to which a ring gear is attached.
Rotational driving apparatuses for testing internal combustion engines are used to test an internal combustion engine under test by rotating the internal combustion engine without igniting it, that is, they are used when performing so-called ‘cold testing’. Cold testing includes valve-related testing, such as the timing at which the intake value and the exhaust valve open and close, and testing of the injection nozzle.
An example of such a rotational driving apparatus for an internal combustion engine is disclosed in JP 10-115576A (hereinafter referred to as “first conventional example”). The first conventional example is illustrated in
FIG. 8. A
ring gear
143
is mounted to a crank shaft
141
, which is the primary shaft of an internal combustion engine
140
that is in the testing position. A rotor
103
is provided as a part of the rotational driving apparatus, and is rotatively driven about the rotation axis of the ring gear
143
(hereinafter, referred to as the “ring gear rotation axis”). An engaging member
130
is provided on the rotor
103
and is slidable in the radial direction of the ring gear
143
(hereinafter, referred to as the “ring gear radial direction”). The engaging member
130
can engage with the ring gear
143
by shifting inwardly in the radial direction. A switching means
110
is provided to shift the engaging member
130
in the ring gear radial direction so as to switch it between an engaged position in which the engaging member
130
engages with the ring gear
143
and a released position in which the engaging member is disengaged. The rotational driving apparatus can rotate the ring gear
143
by rotating the rotor
103
while the engaging member
130
is engaged with the ring gear
143
.
The base end of the engaging member
130
is supported only by the rotor
103
, and its front end portion is provided with an engaging portion
136
that engages the ring gear
143
.
The switching means
110
is provided with a cylindrical body
106
that is fitted, shiftably in the axial direction, to the outside of an output shaft
101
that is rotatively driven about the axis of the rotor
103
, that is, about the ring gear rotation axis, and an L-shaped linkage
127
that is pivotably supported on the rotor
103
and that shifts the engaging member
130
in the ring gear radial direction by pivoting. An end portion of the L-shaped linkage
127
engages a groove provided in the circumferential surface of the cylindrical body
106
so that the L-shaped linkage
127
is pivoted as the cylindrical body
106
is shifted in the ring gear rotation axis direction. In
FIG. 8
, the reference numeral
102
denotes an electric motor that rotatively drives the output shaft
101
, and
107
denotes a cylinder with which the cylindrical body
106
can be shifted in the ring gear rotation axis direction.
Also, the rotor
103
is supported rotatively with respect to a frame
111
via bearings
112
. The rotor
103
and the cylindrical body
106
are free to move relative to one another in the ring gear rotation axis direction and are connected via a key so that they rotate as a single unit. The cylindrical body
106
is linked to the output shaft
101
so that the two rotate as a single unit.
In other words, in the first conventional example, the L-shaped linkage
127
is pivoted due to the cylinder
107
shifting the cylindrical body
106
in the ring gear rotation axis direction. And through this pivoting, the engaging member
130
is slidably shifted in the ring gear radial direction, switching between the engaged position and the released position.
Another conventional example of a rotational driving apparatus is disclosed in JP H02-13732A (hereinafter referred to as “second conventional example”).
FIG. 9
shows the second conventional example. In
FIG. 9
, a ring gear
225
is mounted to a primary shaft (crank shaft)
213
of an internal combustion engine (not shown) in the testing position. This rotational driving apparatus is provided with a shaft-shaped rotor
228
that is rotatively driven about the rotation axis of the ring gear
225
(hereinafter, referred to as the “ring gear rotation axis”). It is also provided with an engaging member
236
that is pivotably supported on the rotor
228
so that it can be shifted in the radial direction of the ring gear
225
(hereinafter referred to as the ring gear radial direction”), and that can engage the ring gear
225
by shifting inward with respect to the radial direction. The rotational driving apparatus is also provided with a switching means
240
that shifts the engaging member
236
in the ring gear radial direction so that it is switched between an engaged position in which it engages the ring gear
225
, and a released position in which it is disengaged. The ring gear
225
can be rotated by rotating the rotor
228
with the engaging member
236
engaged with the ring gear
225
.
A base end of the engaging member
236
on the inward side with respect to the ring gear radial direction is pivotably supported on the rotor
228
, and the front end of the engaging member
236
on the outward side with respect to the ring gear radial direction forms an L-shape that is bent towards the ring gear
225
direction along the ring gear rotation axis direction. An engaging portion
239
that engages the ring gear
225
is provided at the front end of the engaging member
236
.
The switching means
240
is provided with a cylindrical body
232
that is fitted to the outside of the rotor
228
such that it can be shifted in the axial direction, that is, in the ring gear rotation axis direction, and a disk-shaped rotating member
234
that is rotatable relative to the cylindrical body
232
via bearings and that is mounted in an outside fitting state such that it is shiftable in the ring gear rotation axis direction. The fore end portion of the rotating member
234
is pivotably linked to an intermediate portion of the engaging member
236
via link pins
235
. By shifting the cylindrical body
232
in the ring gear rotation axis direction, the engaging member
236
is switched between the engaged position and the released position.
In
FIG. 9
the reference numeral
212
denotes an electric motor that rotatively drives the rotor
228
, and
244
denotes a cylinder with which the cylindrical body
232
can be shifted in the ring gear rotation axis direction and that is operatively connected to the cylindrical body
232
via a pivot link
242
, which pivots about a pivot shaft
241
.
In other words, according to the second conventional example, the engaging member
236
is pivoted in the ring gear radial direction due to the cylinder
244
shifting the cylindrical body
232
in the ring gear rotation axis direction, switching the engaging member
236
between the engaged position and the released position.
Conventionally, an internal combustion engine was tested by running the internal combustion engine at low speeds of about 1200 rpms, for example. However, in order to achieve complete test results and increase the testing accuracy, for example, it is desirable to test the internal combustion engine also at high speeds, such as at 4000 rpms.
In the first conventional example mentioned above, when the internal combustion engine is run at high speeds, the large centrifugal force causes the engaging member, which is supported with respect to the rotor such that it can be slideably shifted in the ring gear radial direction, to shift outward with respect to ring gear radial direction. In order to counter this large centrifugal force and hold the engaging member in the engaged position, it is necessary to increase the control force of the cylinder so that there is a sufficiently large enough control force keeping the engaging member inward in the ring gear radial direction. However, increasing the control force for keeping the engaging member inward in the ring gear
Iwasaki Yahiko
Okuda Yoshifumi
Daifuku Co. Ltd.
McCall Eric S.
Webb Ziesenheim & Logsdon Orkin & Hanson, P.C.
LandOfFree
Rotational driving apparatus for testing internal combustion... does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Rotational driving apparatus for testing internal combustion..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Rotational driving apparatus for testing internal combustion... will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-3262858