Note: Descriptions are shown in the official language in which they were submitted.
63
The present invention relates to a means for
shifting, semi- or fully automatically, multi-stage gear
boxes having mechanical synchronization more particularly
for automotive vehicles, comprising an electric/electronic
control part, whereby gear shifting may be effected manually
by means of a control unit or may be automatically initiated
and controlled with control and actuating devices for the
movement of the transmission and clutch parts which are
displaced during a gear shift, the parts provided for semi
automatic and fully automatic operation being either purely
electrical with solenoid switches or electro-hydraulic or
electro-pneumatie wit solenoid valves and actuating pistons.
Even gear boxes with mechanical synchronizing means
may consist of only one basic transmission but may be
extended for the purpose of achieving additional speeds
by a range and/or a split group, finally, both the basic
transmission and the range and split group may be of counter-
shaft or planetary design, as required.
Robert Bosch's German Auslegeschrift 20 36 732
Jo dated October 5, 1978, discloses a device for the synchronized
shifting of multi-stage gear boxes. Driving power is trays-
furred through a starting and disconnect clutch from the
engine to the counter shaft type gear box. Synchronizing of
the clutches is achieved by central synchronization. Semi-
automatic gear shifting, for example, is made possible by an
electric control unit and a gear preselect or, control being
exclusively electrical and gear change actuation hydraulic.
A fully automatic design is not disclosed.
Robert Bosch's Herman Auslegeschrift 21 36 960
dated July 13 1978, discloses a gear shifting means for semi-
or fully automatic shifting of a multi-stage gear box having
mechanical synchronization
P
-- 1 --
by
associated with the clutches. Shifting is elec-tro-hydraulic
and is effected by an electric or electronic control part
by means of control valves. In symptomatic operation,
push buttons are provided for preselecting the gear to be
engaged and the transmission stage to be shifted and for
initiating the preselected shifting process. In fully
automatic operation the control part receives signals
relating to the operating condition of the relevant automotive
vehicle, e.g. engine r.pnm., accelerator pedal position,
coupling sleeves positions and positions of the clutches
provided between the engine and the transmission.
A factor common to all automatic transmission is
that, except for the "kick-down" and the preelection of
specific speed ranges which are to be shifted only auto-
magically, no intervention by the driver is possible. This
applies particularly in the case of heavy duty traffic and
hilly country when the automatic transmission shifts gears
at a moment when an experienced and careful driver would not
shift. In the case of automatic transmissions of counter-
shaft design, which also have a disconnect clutch for shifting and in which the gear shift is carried out with an
interruption of traction force even though it is brief 9
an unwanted gear shift of this kind may be dangerous.
Adaptation of driving conditions to the vehicle
drive, especially in the case of a heavy vehicle is achieved
very satisfactorily by means of a multi-speed gear box of
counter-shaft and grout design. Even if the gear shifting
means is of good design with means which make gear shifting
easy for the driver, e.g. I- and split shifting with the
shift lever the driver rarely makes use of all possible
favorable adaptations.
Based upon the last mentioned reference, it is
therefore an aim of the present invention to provide an
improved means for shifting semi- or fully automatically,
multi-stage gear boxes having mechanical synchronization,
more particularly for automotive vehicles, comprising an
electric/electronic control part, whereby gear shifting
may be effected manually by means of a control unit or may
be automatically initiated and controlled with control and
actuating devices for the movement of the transmission and
clutch parts which are displaced during a gear shift, i.e.
in such a manner that, in spite of optimal adaptation of the
vehicle to the engine by means of a multi-speed transmission,
the driver is relieved, as far as possible, of the effort of
gear shifting and can intervene, if necessary, in the trays-
mission ratio in the gear train in order to achieve optimal
driving conditions from the economic point of view and a
high degree of safety from rapid driver intervention.
The aforementioned aim is achieved by providing a
means for shifting, semi- or fully automatically, multi-stage
gear boxes having mechanical synchronization, more particularly
for automotive vehicles, comprising an electric/electronic
control part, whereby gear shifting may be effected manually
by means of a control unit or may be automatically initiated
and controlled with control and actuating devices for the
movement of the transmission and clutch parts which are
displaced during a gear shift, characterized in that the
control unit comprises an electrical device for selective
changing over between fully automatic and manual servo-
control, and a programming switch acting, in the automaticrange9 to preselect specific speed ranges and/or gear shift
it
points, a gear shift lever following each gear shift in the
automatic operating range in an H or double-H gate, thus
indicating to the driver or allowing him to feel which gear
is engaged and in the manual servo shift range, when the
said gear shift lever is set effecting actuation of the
gear shift clutches in the gear box and the disconnect
clutch arranged between the engine and the gear box and
in that another electrical switch or pilot valve is arranged
in or on the said control unit preferably on the gear shift
lever by means of which a slow or fast group can be engaged.
Due to the gear shift lever follow-up in automatic drive,
the driver is aware not only of the gear actually engaged
which is important should he have to intervene, especially
in the case of an automatic multi-speed gear box7but he can
also actuate the gear shift lever as required in a H or
double H pattern with which he is familiar. The electric
change over from automatic to manual shifting and vice-versa,
e.g. with the control unit in conjunction with the follow-up
gear shift lever greatly facilitates gear shifting and at
the same time permits rapid intervention. A vehicle thus
equipped can thus cope with all, even difficult, traffic
conditions. In the case of an automatic transmission, the
combination of a gear selecting switch known per so and a
gear lever of the type used in manual gear shifting mechanisms
also provides a compact, functional and simple form of gear
shifting means of this kind.
The configuration of -the invention according to
the other aspects disclosed herein is particularly advantageous.
While the driver is shifting manually, it may also
be desirable to indicate the gear engaged by means of an optical
~2:~2~
gear indicator according to that disclosed hereinafter, the
said indicator being actuated by the automatic transmission
taking into account the preselected speed range and the
preselected shift points.
Especially when the driver intends to change back
to automatic, this indication can assist in verifying the
preselected range and in improving the approach to the gear
selected by the automatic transmission by manual shifting.
The provision of active locking means within the
range of the gear shift lever according to that disclosed
hereinafter, not only prevents inadmissible shifting down,
for example, and thus overspending the engine, but also
ensures that the position of the gear lever is at all times
in agreement with the gear actually selected and this in
turn again simplifies gear shifting
The actuation of the staring and disconnect clutch
in manual shift by means of the gear shift lever according
to that disclosed hereinafter leads to further simplification
since this eliminates the need for a clutch pedal which also
has to be operated by the driver. Smooth engagement of the
clutch may be effected electronically according to the present
invention or by means of a pressure medium and as a function
of centrifugal force again according to that of the present
invention.
During active shifting in operation and in the
clutch during gear shifting, the gear shifting means may be
actuated electromagnetically according to the present
invention, so that the entire shifting means is a purely
electric/electronic installation.
It is also possible, however, for all active
displacements to be effected according to the present
invention, pneumatically or hydraulically. All intermediate
solutions are, of course, also possible. With a gear
shifting means of this kind, therefore, well adapted shifting
is assured in relation to the conditions obtaining, as
regards effort and, by no means least, as rewards safety.
Further details of the invention are explained
hereinafter in conjunction with an example of embodiment
and the drawing attached hereto, wherein:
Figure 1 is a diagrammatical representation of a
gear shifting means in accordance with the present invention,
Figure 2 shows the manual gear shift lever shown
in Fig. 1, in conjunction with a double H gear shift pattern.
Referring to the drawings in Fig. 1, 1 represents
the multi-stage gear box having 4 speeds in the basic trays-
mission 11, followed by a group transmission 12 having two
ranges, and a split group 13 arranged at the input to the
gear box, thus producing, as is known, 16 shiftable forward
speeds. The speeds of basic transmission 11, doubled by the
group transmission 12 to 8 speeds, may be shifted in
accordance with the known double-H pattern (see Fig. 2).
The split group makes it possible to double the number of
speeds again, thus providing one fast and one slow group,
each having 8 speeds which may be preselected alternately
with -the electrical switch or pilot valve 33 on gear shift
lever 31.
Numeral 2 is an electrical control part with leads
71 running to a source of power, i.e. battery 7, 51 to the
accelerator pedal 5, i.e. gas pedal, I to a means for
determining the room of the gear box output shaft, 41 to
gear indicator 4, and 22 to control unit I The latter may
be connected to actuating devices I 15, 16, 17, 81 for
base transmission 12, for example to the shaft or to the
coupling sleeves themselves for the group and split trays-
missions 12~13 and for the starting and disconnect clutch 8,
by either electrical or hydraulic lines 35~ If the gear
shifting means is designed as an electro-pneumatic unit, there
is used a source of compressed air 61 with an aerating and
venting valve 6, the control thereof being effected through
lines 62, for example, from electronic control part 2. If
switch 32 is set to automatic and an appropriate program is
preselected (programming switch 34), all gear shifts in the
forward speed range are controlled solely from electronic
control part 2, as a function of rum and driving conditions,
for example, as already known. In this case, gear shift
lever 31 is caused to follow the gear shifts in parallel with
actuating devices 14,15 for basic and group transmissions
11,12 by means of an actuating device (not shown) located
in control unit 3. From the position of the gear shift
lever in -the double H gate (Fig. I the driver can easily
see or feel which gear is engaged. By means of a switch or
pilot valve 33 on gear shift lever 31, the fast or slow
split group may be preselected and, at the same time 9 shifted
and, in the case of a preelection the shift itself may be
effected by -the accelerator pedal for example, so that at
the most only 8 speeds need be shifted automatically. The
automatic shift may, of course, also be arranged to include
all 16 speeds, the pilot valve or electrical switch 33 acting
only during manual shifting.
lo
In the event switch 32, which may be arranged on
gear shift lever 31 or on the dash board for example is set
to manual operation, no more automatic shifting takes place.
Instead, all gear shifting must be carried out by the driver
himself with gear shift lever 31 and the double H gate and
with switch or pilot valve 33 in known fashion. However,
the driver can see from gear indicator 4 the gear which the
automatic transmission would engage if manual shift had not
been selected. It is thus easily possible to approach this
gear before changing back to automatic. The said gear
indicator 4 may be switched on at all times or only during
manual gear shifting.
Another advantageous variant makes it possible for
all gear shifts to be effected automatically on the one
hand, and, if switch 32 is set to manual, the speeds of the
basic transmission and follow-up group, i~e9 8 speeds, can
key selected by the driver himself through the double H gate.
In this case, the split group is either inoperative or
continues to be actuated automatically and is not affected
by the driver.
In this case, pilot valve 33 may be dispensed with.
Programming switch 34 may be a generally known selector
lever as used with automatic transmissions, for example
with the settings P - R - - D - 2 - 1, it may also be
simplified, for example with programs only in the forward
range.
All manual shifting is carried out with an auxiliary
force comprising a transmitter in control unit 3 and receivers
14, 15, 16, 17, 81 on gear box 1 and starting and disconnect
clutch 8.
