Electric switch apparatus for an automatic clutch in an automotive power train using a manual power transmission system

In an automotive power train including a manually shifted power transmission system and an automatically operated clutch unit, the clutch unit is operated by electric actuating means which is controlled by means of an electric switch apparatus which includes first and second switch means responsive to a manipulative force applied to the manually operated transmission gearshift lever, and third to fifth switch means responsive to the movement of the transmission gearshift lever toward the various gear positions of the lever and arranged to be selectively open and closed in accordance with predetermined schedules.

The present invention relates to an automotive power train of the type 
having a manually shifted power transmission system and an automatically 
operated clutch unit intervening between the transmission system and the 
output shaft of the engine to drive the power train. The clutch unit of 
the power train to which the present invention appertains is of the type 
which is operated by electrically operated clutch actuating means which is 
adapted to operate the clutch unit depending upon the gear positions 
selected in the gear mechanism of the power transmission system, Thus, the 
present invention is more specifically concerned with an electric switch 
apparatus for use with such clutch actuating means. 
In a manually shifted power transmission system of an ordinary automotive 
power train which has a manually operated clutch between the output shaft 
of the engine and the gear mechanism of the transmission system, gear 
shifts are effected by manipulating a manually operated gearshift lever 
mounted on the steering column or the floor board of the vehicle. Before 
the gearshift lever is to be moved to make a gear shift in a power 
transmission system of this type, the driver of the vehicle must take an 
action to uncouple the clutch which has been transmitting the driving 
power from the engine output shaft to the gear mechanism of the 
transmission system. The gearshift lever is thus manipulated by the 
vehicle driver with the clutch held in an uncoupled condition interrupting 
the transmittion of the driving power from the engine output shaft to the 
power transmission gear mechanism. After the gear shift is completed, the 
vehicle driver couples the clutch for a second time so that the driving 
power being delivered from the engine output shaft is allowed to reach the 
transmission gear mechanism. 
In contrast to an automotive power train of this type, there is known an 
automotive power train using an automatically operated clutch unit which 
is adapted to be uncoupled in an automatic fashion when the gearshift 
lever is being manipulated by the vehicle driver so that the transmission 
of the driving power from the engine output shaft to the transmission gear 
mechanism is interrupted while shifts between gear positions are being 
made in the transmission system. The gearshift lever for use in the power 
transmission system of an automotive power train of this character is 
operated with or without the aid of hydraulic or pneumatic pressure, while 
the clutch unit is operated with the assistance of a suitable driving 
force which is usually produced by a hydraulic pressure. 
In an automotive power train thus using a manually shifted power 
transmission system and an automatically operated clutch unit, means must 
be provided to transmit the movement of the transmission gearshift lever 
to the clutch unit for allowing the clutch unit to stay in the coupled 
condition in the absence of a manipulative effort applied to the gearshift 
lever and causing the clutch unit to uncouple when the gearshift lever is 
being manipulated to effect a gear shift in the transmission gear 
mechanism. A typical example of such means comprises a hydraulic or 
pneumatic control system including a relay-operated or solenoid-operated 
clutch control valve electrically connected to a switching device which is 
mounted on or in conjunction with the transmission gearshift lever. The 
hydraulic or pneumatic control system is arranged so that the switching 
device is closed and the clutch control valve is in a condition to 
maintain the clutch unit in the uncoupled condition when the transmission 
gearshift lever is being manipulated to make a gear shift in the 
transmission gear mechanism. When the gear shifting operation is complete 
and the transmission gearshift lever is released, the switching device is 
rendered open and accordingly the clutch control valve is brought into a 
condition allowing the clutch unit to stay in the coupled condition. 
One drawback of a hydraulic or pneumatic clutch control system of this 
nature is that there is a certain amount of delay in allowing the clutch 
unit to couple after the switching unit is made open in response to 
release of the manipulative force from the transmission gearshift lever. 
This causes the engine to run idle until the clutch unit is allowed to 
fully couple after the transmission gearshift lever has been released from 
the manipulative force, with the result that a forceful mechanical shock 
is produced in the engine when the clutch unit is coupled. If, 
furthermore, it happens that the operator of the vehicle touches the 
transmission gearshift lever unintentionally while vehicle is being driven 
with the accelerator pedal depressed, the clutch unit is caused to 
uncouple unnecessarily and causes the engine to race. To avoid these 
drawbacks, the switching device of the control system is required to 
include, in addition to those switch elements which are responsive to the 
manipulative effort applied to the transmission gearshift lever, extra 
switch elements which are capable of responding to various minute motions 
of the transmission gearshift lever. Provision of such extra switch 
elements not only results in intricate construction of the control system 
as a whole and adds to the seriousity of the space requirement for the 
installation of the switching device on or in conjunction with the 
transmission gearshift lever but requires extremely time-taking, skilled 
techniques in assembling the switching device because the individual 
switch elements must be adjusted not only in relation to the motions of 
the transmission gearshift lever but with respect to each other so that 
each of the switch elements is enabled to properly perform the function 
which is allocated to the particular switch element. 
It is, accordingly, the object of the present invention to provide, in an 
automotive power train of the type including a manually shifted power 
transmission system and an automatically operated clutch unit controlled 
by electrically operated clutch control means, an improved switch 
apparatus which has a simple and small-sized construction and which is 
easy and economical to manufacture and to install in an automotive vehicle 
in conjunction with the manually operated transmission gearshift lever. 
In accordance with the present invention, there is provided, in an 
automotive power train having a power transmission system including a gear 
mechanism having a plurality of gear positions, a manually operated 
gearshift lever which is movable in opposite fore-and-aft directions and 
opposite lateral directions, and a control member operatively connecting 
the gearshift lever to the gear mechanism, the control member being 
axially movable in response to the movement of the gearshift lever in each 
of the aforesaid lateral directions thereof and rotatable about its axis 
in response to the movement of the gearshift lever in each of the 
aforesaid fore-and-aft directions thereof for thereby producing any one of 
the gear positions in the gear mechanism, an automatically operated clutch 
unit intervening between said gear mechanism and a driving source, and 
electrically operated clutch control means for operating the clutch unit 
in response to a condition in which a shift is being made between the gear 
positions in the gear mechanism from the gearshift lever, the clutch 
control means being operative to allow the clutch unit to couple when 
de-energized and to cause the clutch unit to uncouple when energized, an 
electric switch apparatus electrically connected between a power source 
and the clutch control means and comprising a first switch assembly 
responsive to the movement of the gearshift lever in each of the lateral 
directions thereof and including a parallel combination of first switch 
means which is normally open and which is to close in response to the 
movement of the gearshift lever in one of the lateral directions thereof, 
and second switch means which is normally open and which is to close in 
response to the movement of the gearshift lever in the other lateral 
directions thereof, and a second switch assembly responsive to the 
rotation of the control member about the axis thereof and including a 
rotatable member rotatable with the control member about an axis 
substantially in line with the axis of rotation of the control member, a 
stationary member positioned adjacent the rotatable member, the control 
member being rotatable relative to the stationary member and axially 
movable relative to both the stationary member and the rotatable member, a 
set of contact elements extending in radial directions of the rotatable 
member and spaced apart from each other about the axis of rotation of the 
rotatable member, a set of contact elements extending arcuately about the 
axis of rotation of the rotatable member and spaced apart from each other 
in circumferential directions of the rotatable member, one of the two sets 
of contact elements being fixedly mounted on the rotatable member for 
constituting movable contacts and the other set of contact elements being 
fixedly mounted on the stationary member for constituting stationary 
contacts which are to be respectively contacted by the above mentioned 
movable contacts, each of the movable contacts and the associated one of 
the stationary contacts constituting in combination clutch control switch 
means which is to open and close depending upon the rotational position of 
the rotatable member relative to the stationary member, first and second 
switch assemblies being electrically connected in series with the clutch 
control means. 
The above mentioned control member preferably has an end portion engageable 
with the aforesaid rotatable member and has formed in the end portion an 
elongated slot extending in parallel with the direction of the axial 
movement of the control member and having a laterally enlarged end portion 
which is open at the end of said end portion, wherein the aforesaid second 
switch assembly further includes a shaft supporting and rotatable with the 
rotatable member and having at one end of the shaft an axial projection 
protruding into the elongated slot in the control member for providing 
engagement between the control member and the shaft when the above 
mentioned projection is located out of the enlarged portion of the slot in 
the rotatable member. 
The respective clutch control switch means constituted by the individual 
combinations of the movable and stationary contacts may comprise third 
switch means to close when the gearshift lever is within a predetermined 
positional range having one end at the limit of the movement of the 
gearshift lever in one of the lateral direction thereof and the other end 
immediately anterior to the limit of the movement of the gearshift lever 
in the other of the lateral directions thereof, and fourth switch means to 
close when the gearshift lever is within a predetermined positional range 
having one end immediately anterior to the limit of the movement of the 
gearshift lever in the aforesaid one of the lateral directions thereof and 
the other end at the limit of the movement of the gearshift lever in the 
aforesaid other of the lateral directions thereof the third and fourth 
switch means being electrically connected in parallel to the clutch 
control means across the first and second switch means, respectively. In 
this instance, the clutch control switch means may further comprise fifth 
switch means to close when the gearshift lever is within a predetermined 
positional range having opposite ends immediately anterior to the limits 
of the movement of the gearshift lever in the aforesaid lateral directions 
thereof, the fifth switch means being electrically connected to the clutch 
control means in parallel with the above mentioned third and fourth switch 
means.

Referring to the drawings, the automotive power train into which an 
electric switch assembly embodying the present invention is shown in FIG. 
1A as comprising a torque converter and clutch assembly 10 and a gear 
mechanism 12 which forms part of a manually shifted power transmission 
system. The torque converter and clutch assembly 10 is provided 
intermediate between the crankshaft 14 of an automotive internal 
combustion engine (not shown) and a transmission input shaft 16 extending 
in alignment with the axis of rotation of the engine crankshaft 12. The 
transmission gear mechanism 12 has an output shaft 18 which is connected 
through a front universal joint 20 to a propeller shaft 22. As is well 
known, the propeller shaft 22 in turn is connected through a final drive 
unit and a differential to rear axles, thereby completing the power train 
of the vehicle, as is well known. 
The torque converter and clutch assembly 10 consister of a torque converter 
24 and a clutch unit 26. The torque converter 24 is shown, by way of 
example, to be of the three-member design consisting of a driving member 
or impeller 28, a driven member or turbine 30 and a stationary member or 
stator 32. The impeller 28 is connected to the engine crankshaft 14 by a 
torque converter torus cover 34 and is thus rotatable with the engine 
crankshaft 14 and the torus cover 34 about the axis of rotation of the 
crankshaft 14. The turbine 30 is positioned in front of the impeller 28 
and is secured to a generally disc-shaped turbine support disc which is 
integral with or securely connected to a clutch housing 36. The clutch 
housing 36 is arranged to define first and second variable-volume chambers 
38 and 40 within the torus cover 34. The first variable-volume chamber 38 
is open in front of the clutch unit 26 and the second variable-volume 
chamber 40 is open at the rear of the clutch unit 24. The stator 32 is 
positioned between the impeller 28 and the turbine 30 and is supported by 
a stationary stator support hollow shaft 42 through a torque converter 
one-way clutch assembly 44. The transmission input shaft 16 extends 
through this stator support hollow shaft 42 in coaxial relationship to the 
hollow shaft 42. 
On the other hand, the clutch unit 24 comprises a generally annular clutch 
piston 46 which is positioned between the converter torus cover 34 and the 
clutch housing 36. The clutch piston 46 is axially movable toward and away 
from the inner face of the front center portion of the torus cover and has 
its front face exposed to the above mentioned first variable-volume 
chamber 38 formed within the converter torus cover 34 by means of the 
clutch housing 36. Between the clutch housing 34 and the clutch piston 46 
thus arranged is provided a clutch disc 48 which is securely mounted on a 
disc hub 50 splined to the transmission input shaft 16 and which is thus 
axially movable toward and away from the front face of the clutch housing 
34. The previously mentioned second variable-volume chamber 40 is formed 
between the front face of the clutch housing 34 and the rear face of the 
clutch disc 48 which is thus arranged. When, thus, a fluid pressure is 
developed in the first variable-volume chamber 38 in the absence of a 
fluid pressure in the second variable-volume chamber 40, the clutch piston 
46 is axially moved away from the rear face of the converter torus cover 
34 by the force resulting from the fluid pressure acting on the front face 
of clutch piston 46. Under these conditions, the clutch piston 46 is in 
pressing engagement with the clutch disc 48 which is accordingly forced 
against the front face of the clutch housing 36 integral with or securely 
connected to the turbine 30 of the torque converter 24 so that the clutch 
unit 26 as a whole is rotatable with the turbine 30 and as a consequence 
the driving torque delivered from the engine crank shaft 14 is transmitted 
to the transmission input shaft 16 through the impeller 28 and turbine 30 
of the torque converter 24, the clutch housing 36 and the clutch disc 48. 
When, conversely, a fluid pressure is developed in the second 
variable-volume chamber 40 in the absence of a fluid pressure in the first 
variable-volume chamber 38, the clutch piston 46 is forced against the 
rear face of the converter torus cover 34 by the force resulting from the 
fluid pressure acting on the rear face of the clutch piston 46. Under 
these conditions, the clutch piston 46 is disengaged from the clutch disc 
48 which is accordingly separated from the turbine 30 of the torque 
converter 24 with the result that the driving connection between the 
engine crankshaft 14 and the transmission input shaft 16 is interrupted 
between the clutch housing 36 and the clutch disc 48. 
The gear mechanism 12 of the power transmission system is of a countershaft 
synchromesh type and comprises a transmission mainshaft 52 in line with 
the transmission input and output shafts 16 and 18 and a transmission 
countershaft 54 which extends in parallel with the transmission mainshaft 
52. The transmission mainshaft 52 is separate from the transmission input 
shaft 16 and is integral with the transmission output shaft 18. The 
transmission output shaft 54 is supported by the transmission casing (not 
shown) in such a manner as to be rotatable independently of the 
transmission mainshaft 52. The countershaft transmission gear mechanism 12 
is assumed, by way of example, to be of the three-forward-speed and 
one-reverse-speed design and comprises a transmission main drive gear 56 
secured to the transmission input shaft 16, mainshaft low, overdrive and 
reverse gears 58, 60 and 62 which are splined to the mainshaft 52, and a 
transmission parking-lock gear 64 which is secured to the mainshaft 52. On 
the other hand, the transmission countershaft 54 has securely mounted 
thereon a countershaft gear assembly which consists of a countershaft main 
gear 66 in constant mesh with the main drive gear 56, a countershaft low 
gear 68 in constant mesh with the mainshaft low gear 58, a countershaft 
overdrive gear 70 in constant mesh with the mainshaft overdrive gear 60, 
and a countershaft reverse gear 72 which is in constant mesh with a 
transmission reverse-idler gear 74 mounted on a transmission reverse-idler 
shaft 76 journalled to the transmission casing. The transmission 
reverse-idler gear 74 in turn is in constant mesh with the mainshaft 
reverse gear 62 as indicated by a broken line in FIG. 1A. The transmission 
parking-lock gear 62 is engageable with a pawl 78 which is adapted to be 
brought into locking engagement with parking-lock gear 62 when moved. 
The countershaft transmission gear mechanism 12 further comprises first and 
second synchronizers 80 and 82 which are splined to the transmission 
mainshaft 52. The first synchronizer 80 is positioned between the main 
drive gear 56 and the mainshaft low gear 58 and is thus adapted to be 
coupled with the main drive gear 56 or the mainshaft low gear 58 for 
producing a direct-drive gear or low-speed gear condition in the 
transmission gear mechanism 12. The second synchronizer 82 is positioned 
between the mainshaft overdrive and reverse gears 60 and 62 and is thus 
adapted to be coupled with the mainshaft overdrive gear 60 or the 
mainshaft reverse gear 62 for producing an overdrive gear or reverse-drive 
gear condition in the transmission gear mechanism 12. 
The first synchronizer 80 is engaged by a low and direc-drive shift rod 84 
and, likewise, the second synchronizer 82 is engaged by an overdrive and 
reverse shift rod 84. Furthermore, the pawl 78 associated with the 
transmission parking-lock gear 64 is engaged by a cam 88 which is 
connected to a cam actuating rod 90. The shift rods 82 and 84 and the cam 
actuating rod 90 are operatively in engagement with a common striking rod 
92 having arms 94 and 94' which are engageable as at 96 and 96' with the 
shift rods 84 and 86, respectively. The striking rod 92 is arranged to be 
axially movable in opposite directions as indicated by arrowheads a.sub.1 
and a.sub.2 and rotatable about its center axis in opposite directions as 
indicated by arrowheads b.sub.1 and b.sub.2. The striking rod 92 thus 
arranged axially extends through a bore 97 formed in the transmission 
casing C and is connected by a suitable link 98 to a manually operated 
transmission gearshift lever 100 having a knob 102 and pivotally support 
by a bracket 104 as at 106. The bracket 104 may be mounted on or form part 
of the steering column or the floor board of the vehicle. 
The manually operated gearshift lever 100 is assumed, by way of example, to 
be movable from a neutral gear position "N" to five different gear 
positions which consist of a low gear position "L", a direct-drive gear 
position "D", an overdrive gear position "OD", a reverse-drive gear 
position "R" and a parking gear position "P", as diagrammatically 
illustrated in FIG. 1B. More specifically, the gearshift lever 100 is 
rotatable about the pivotal point 106 in opposite lateral directions 
A.sub.1 and A.sub.2 for selecting the low and direct-drive gear positions 
"L" and "D", the overdrive gear position "OD" or the reverse-drive and 
parking gear positions "R" and "P" and in opposite fore-and aft directions 
B.sub.1 and B.sub.2 for making a shift from the neutral gear position "N" 
to the low or direct-drive gear position "L" or "D", the overdrive gear 
position "OD" or the reverse-drive or parking gear position "R" or "P". 
When the gearshift lever 100 is held in the neutral gear position "N", 
none of the gears 56, 58, 60 and 62 so that the transmission mainshaft 52 
is disconnected, in effect, from the transmission input shaft 16. Under 
this condition, the cam 88 provided in association with the transmission 
parking-lock gear 64 is maintained in a position having the pawl 78 
disengaged from the parking-lock gear 64. Movement of the gearshift lever 
100 in the lateral or gear-selecting direction A.sub.1 or A.sub.2 is 
converted by means of the mechanical linkage 98 into movement of the 
striking rod 92 in the axial direction a.sub.1 or a.sub.2 and selects one 
of the shift rods 84 and 86 to be moved by the strking rod 92. On the 
other hand, movement of the gearshift lever 100 in the fore-and-aft or 
gear-shifting direction B.sub.1 or B.sub.2 brings about rotation of the 
striking rod 92 in the direction b.sub.1 or b.sub.2, respectively, about 
the axis of the rod 92. The rotational motion of the striking rod 92 is 
transmitted through the shift rod 84 or 86 to the first or second 
synchronizers 80 or 82, respectively, and causes the first synchronizer 80 
to engage either the transmission main drive gear 56 or the mainshift low 
gear 58 or the second synchronizer 82 to engage either the mainshaft 
overdrive gear 60 or the mainshaft reverse gear 62. In the arrangement 
shown in FIG. 1A, it is assumed that the first and second synchronizers 80 
and 82 are brought into engagement with the mainshaft low and reverse 
gears 58 and 62, respectively, when the striking rod 92 is driven to turn 
in the direction b.sub.1 with the gearshift lever 100 moved in the 
gear-shifting direction B.sub.1 and into engagement with the transmission 
main drive gear 56 and the mainshaft overdrive gear 60, respectively, when 
the striking rod 92 is driven to turn in the direction b.sub.2 with the 
gearshift lever 100 moved in the gear-shifting direction B.sub.2. When the 
gearshift lever 100 is moved to the parking position "P", the cam 88 
connected to the cam actuating rod 90 is forced to move the associated 
pawl 78 into locking engagement with the transmission parking-lock gear 
64. 
When the vehicle equipped with the power train thus constructed and 
arranged is in operation, a fluid pressure is developed in the first 
variable-volume chamber 38 within the torque converter torus cover 34 so 
that, if there is no fluid pressure developed in the second 
variable-volume chamber 40 within the clutch housing 36, the clutch unit 
26 as a whole is held in the coupled condition establishing a driving 
connection from the engine crankshaft 14 to the transmission input shaft 
16 through the torque converter 24, as previously described. The 
transmission main drive gear 56 on the input shaft 16 andand accordingly 
the gear assembly on the transmission countershaft 54 having the 
countershaft main gear 66 in constant mesh with the main drive gear 56 are 
thus kept driven with the shafts 16 and 66, respectively. If, under these 
conditions, the manually operated gearshift lever 100 is in the neutral 
position "N", none of the gears on the transmission mainshaft 52 is 
engaged by the first and second synchronizers 80 and 82 as previously 
noted so that the mainshaft low and overdrive gears 58 and 60 in mesh with 
the countershaft low and overdrive gears 68 and 70 and the mainshaft 
reverse gear 62 in mesh with the reverse-idler gear 74 meshing with the 
countershaft reverse gear 72 are left to idle on the transmission input 
shaft 52. The transmission mainshaft 52 is thus held at rest and, as a 
consequence, no driving torque is transmitted to the propeller shaft 22 
from the transmission input shaft 16 which is being driven from the engine 
crankshaft 14. If the gearshift lever 100 is then moved manually into the 
low gear position "L", the striking rod 92 is driven to turn in the 
direction a.sub.1 about the axis thereof and causes the low and 
direct-drive shift rod 84 to move the first synchronizer 80 to move 
rearwardly on the transmission input shaft 52 for engagement with the 
mainshaft low gear 58. When the first synchronizer 80 is thus brought into 
mating engagement with the mainshaft low gear 58, the gear 58 becomes 
rotatable with the transmission mainshaft 52 so that a driving torque is 
transmitted from the transmission input shaft 16 to the transmission 
mainshaft 52 through the main drive gear 56, the countershaft main gear 
66, the countershaft 54, the countershaft low gear 68, the mainshaft low 
gear 58 and the first synchronizer 80, thereby producing a low gear 
condition in the transmission gear mechanism 12. 
If the manually operated gearshift lever 100 is thereafter moved from the 
low gear position "L" to the direct-drive gear position "D", the striking 
rod 92 is driven to turn in the direction b.sub.2 about its axis and 
causes the first synchronizer 80 to move forwardly on the transmission 
mainshaft 52. The first synchronizer 80 is thus disengaged from the 
mainshaft low gear 58 and is brought into mating engagement with the main 
drive gear 56 on the transmission input shaft 16. The transmission input 
shaft 16 is now coupled with the transmission mainshaft 52 through the 
main drive gear 56 and the first synchronizer 80, thereby completing a 
direct-drive connection between the transmission input shaft 16 and the 
transmission mainshaft 52. 
When the maunally operated gearshift lever 100 is further mainpulated and 
is moved from the direct-drive gear position "D" to the overdrive gear 
position across the meutral gear position "N", the striking rod 92 is once 
rotated in the direction b.sub.1 about the axis thereof and moves the 
first synchronizer 80 out of engagement with the main drive gear 56. The 
striking rod 92 is then moved in the axial direction a.sub.1 selecting the 
overdrive and reverse shift rod 86 and is thereafter rotated in the 
direction b.sub.2 about the axis thereof so as to cause the shift rod 86 
to move the second synchronizer 82 forwardly on the transmission mainshaft 
52. The second synchronizer 82 is thus brought into mating engagement with 
the mainshaft overdrive gear 60 so that a driving torque is transmitted 
from the transmission input shaft 16 to the transmission mainshaft 52 
through the main drive gear 56, the countershaft main gear 66, the 
countershaft 54, the countershaft overdrive gear 70, the mainshaft 
overdrive gear 60 and the second synchronizer 82, producing an overdrive 
gear condition in the transmission gear mechanism 12. 
On the other hand, if the manually operated gearshift lever 100 is moved 
from the neutral gear position "N" to the reverse-drive gear position "R", 
the striking rod 92 is rotated in the direction b.sub.1 about the axis 
thereof and causes the second synchronizer 82 to move rearwardly on the 
transmission mainshaft 52 fro mating engagement with the mainshaft 
reverse-drive gear 62. When the mainshaft reverse-drive gear 62 is thus 
engaged by the second synchronizer 82, a driving torque is transmitted 
from the transmission input shaft 16 to the transmission mainshaft 52 
through the main drive gear 56, the countershaft main gear 66, the 
countershaft 54, the countershaft reverse-drive gear 72, the reverse-idler 
gear 74, the mainshaft reverse-drive gear 62 and the second synchronizer 
82, thereby producing in the transmission gear mechanism a reverse-drive 
gear condition causing the transmission mainshaft 54 to rotate in the 
direction opposite to the direction of rotation of the transmission input 
shaft 16. 
If the manually operated gearshift lever 100 is moved from the neutral gear 
position "N" to the parking gear position "P", then the cam actuating rod 
90 is moved in a direction to press the associated cam 88 against the pawl 
78, which is accordingly brought into locking engagement with the 
transmission parking-lock gear 64 fixed on the transmission mainshaft 52. 
Since, under these conditions, the first and second synchronizers 80 and 
82 are in engagement with none of the gears 56, 58, 60 and 62, the 
transmission mainshaft 52 is locked by the pawl 78 so that the power train 
posterior to the transmission mainshaft 52 is held in a locked condition. 
Each time the manually operated gearshift lever 100 is moved to make a 
shift between the various gear positions as above discussed, the fluid in 
the first variable-volume chamber 38 within the torque converter torus 
cover 34 is discharged from the chamber 38 and at the same time a fluid 
under pressure is directed into the second variable-volume chamber 40 
within the clutch housing 36. The fluid pressure thus acting on the rear 
face of the clutch piston 46 forces the clutch disc 48 to move toward the 
rear face of the converter torus cover 34 in the absence of a fluid 
pressure acting on the front face of the clutch piston 46 and allows the 
clutch disc 48 to be disengated from the clutch housing 36, interrupting 
the driving connection from the torque converter 24 to the transmission 
input shaft 16. The fluid pressure developed in the second variable-volume 
chamber 40 is maintained and accordingly the clutch unit 26 is kept 
uncoupled throughout the period of time for which the gearshift lever 100 
is being manipulated to make a shift in the transmission gear mechanism. 
When the shifting is complete and the gearshift lever 100 is released from 
the manipulative effort, the pressurized fluid in the second 
variable-volume chamber 40 is discharged therefrom and a fluid under 
pressure is introduced into the first variable-volume chamber 38 within 
the torque converter torus cover 34, thereby causing the clutch unit 26 to 
couple for a second time. The clutch unit 24 is in this fashion uncoupled 
and coupled each time the manually operated gearshift lever 100 is 
manipulated to make a shift between the various gear positions in the 
transmission gear mechanism 12. FIG. 2 shows a preferred example of an 
electrically operated hydraulic control system which is adapted to control 
the supply and discharge of the fluid pressures to and from the first and 
second variable-volume chambers 38 and 40 in the torque converter and 
clutch assembly 10 when the manually operated gearshift lever 100 is thus 
manipulated to make a shift in the transmission gear mechanism 12. 
In FIG. 2, the torque converter and clutch assembly 10 which has been 
illustrated only schematically in FIG. 1A is depicted in more detail. 
Thus, the torque converter torus cover 34 is shown having a front boss 
portion 108 projecting forwardly from the torus cover 34 and a rear hub 
portion 110 projecting rearwardly from the torus cover 34 and formed with 
a counterbore 112 which is open at the rear end of the hub portion 110 and 
which has a center axis in line with the axis of rotation of the 
transmission input shaft 16. The transmission input shaft 16 has a front 
end portion journalled in the counterbore 112 in the rear hub portion 110 
of the torus cover 34 by means of a bushing which is received in the 
counterbore 112. Though not shown, the front hub portion 108 of the 
converter torus cover 34 is received in a pilot bearing by means of which 
the flywheel of the engine connects the engine crankshaft 14 (FIG. 1A) to 
the converter torus cover 34. The transmission input shaft 16 further has 
an axially serrated portion 114 adjacent the above mentioned front end 
portion of the shaft 16. 
The previously mentioned disc hub 50 of the clutch disc 48 forming part of 
the clutch unit 26 is formed with internal serrations and is splined to 
the externally serrated portion 114 of the transmission input shaft 16. An 
annular disc web 116 is splined along its inner circumferential edge to 
the outer circumferential end portion of the clutch disc hub 50. On both 
sides of the clutch disc web 116 are positioned front and rear clutch 
plates 118 and 118' which are splined along their respective outer edge 
portions to an intermediate flange portion of the clutch housing 36. The 
front clutch plate 118 is positioned between the clutch piston 46 and the 
clutch disc web 50 while the rear clutch plate 118' is positioned between 
the clutch disc web 116 and the previously mentioned turbine support disc 
which forms part of the clutch housing 36 and which is designated by 
reference numeral 120 in FIG. 2. Between the clutch piston 46 and the 
front clutch plate 118 is provided a spring assembly 122 which is 
operative to control the frictional forces to be produced between the 
clutch disc web 116 and the front and rear clutch plates 118 and 118' when 
a fluid pressure is built up in the first variable-volume chamber 38 
within the converter torus cover 34 and forces the clutch piston 46 to 
press the front clutch plate 118 against the clutch disc web 116 and 
accordingly press the clutch disc web 116 against the rear clutch plate 
118'. Designated by numeral 124 is one of guide pins which are secured to 
the clutch housing 36 and which extend in parallel with the axis of 
rotation of the clutch housing 36. These guide pins 124 are axially 
slidably received in holes formed in the clutch piston so that the angular 
position of the clutch piston 46 about the center axis thereof is 
maintained unchanged when the clutch piston 46 is axially moved relative 
to the clutch housing 36. The clutch piston 46 has an inner flange portion 
received on the outer peripheral surface of the rear hub portion 50 of the 
converter torus cover 34, as shown. 
The turbine 30 of the torque converter 24 is shown comprising a torus 
member 126 which is formed with a plurality of openings 128 providing 
communication between the interior of the turbine 30 and the first 
variable-volume chamber 38 within the converter torus cover 34. The torus 
member 128 thus forming part of the turbine 30 of the torque converter 24 
is secured to the turbine support disc 120 so that the clutch housing 36 
and the clutch plates 118 and 118' on the clutch housing 36 are rotatable 
with the turbine 30 about the axis of rotation of the turbine 30. The 
turbine support disc 120 is slidably supported on the outer peripheral 
surface of a front end portion of the previously mentioned stator support 
hollow shaft 42. 
The torque converter one-way clutch assembly 44 supporting the stator 32 of 
the torque converter 24 on the stator support hollow shaft 42 comprises a 
hub 130 which is splined to the hollow shaft 42, and a generally 
ring-shaped cam 132 which is coaxially and slidably received on the outer 
peripheral surface of the hub 130. The cam 132 is formed with a plurality 
of grooves which are arranged in symmetry about the center axis of the hub 
130 and which are open to the outer peripheral surface of the hub 130. 
Spring loaded rollers 134 are received in these grooves and are in 
rollable contact with the outer peripheral surface of the hub 130 for 
thereby permitting the cam 132 to revolve on the hub 130 in one direction 
about the axis of rotation of the transmission input shaft 16. The cam 132 
is secured to the stator 32 of the torque converter 24 by suitable 
fastening members (not shown) so that the stator 32 is rotatable in the 
direction of rotation of the transmission input shaft 16 and is locked up 
to the hub 130 on the stator support hollow shaft 42 when urged to turn in 
the opposite direction about the axis of rotation of the transmission 
input shaft 16. 
Behind the torque converter 24 is provided a transmission oil pump unit 136 
which is mounted on a pump support sleeve 138 securely connected to the 
impeller 28 of the torque converter 24 and extending in coaxial 
relationship with the stator support hollow shaft 42. The pump support 
sleeve 138 has its inner peripheral surface which is radially spaced apart 
from the outer peripheral surface of an intermediate axial portion of the 
stator support hollow shaft 42 so that a cylindrical first fluid 
passageway 140 is formed between the outer peripheral surface of the 
intermediate axial portion of the stator support hollow shaft 42 and the 
inner peripheral surface of the pump support sleeve 138. The fluid 
passageway 140 is in constant communication with the interior of the 
turbine 30 of the torque converter 24 and through the openings 128 in the 
turbine torus member 126 with the first variable-volume chamber 38 within 
the converter torus cover 34. The stator support hollow shaft 42 in turn 
has its inner peripheral surface radially spaced apart from the outer 
peripheral surface of the transmission input shaft 16 and thus forms a 
cylindrical second fluid passageway 142 is formed between the outer 
peripheral surface of the transmission input shaft 16 and the inner 
peripheral surface of the stator support hollow shaft 42. Constant 
communication is provided between the second fluid passageway 142 and the 
second variable-volume chamber 40 in the clutch housing 36 in a suitable 
manner. The turbine support disc 120 securely connected to or integral 
with the clutch housing 36 is formed with a small aperture 144 providing 
communication between the second variable-volume chamber 40 and the 
internal space of the converter turbine 30 so that the fluid in the torque 
converter 24 is enabled to be discharged at a limited rate from the torque 
converter 24 into the second variable-volume chamber 40 through the 
aperture 144 and from the variable-volume chamber 40 into the second fluid 
passageway 142 when the clutch unit 26 is coupled, thereby restricting the 
rise of the temperature of the working fluid in the torque converter 24. 
The transmission oil pump unit 136 comprises an engine-driven oil pump 136' 
which has a suction port communicating with a fluid inlet passageway 146 
leading from a fluid reservoir 148 through a fluid strainer 149. The oil 
pump 136' further has a delivery port communicating with a fluid outlet 
passageway 150 leading to branch passageways 152 and 154 which terminate 
in a fluid-pressure regulator valve unit 156 and a clutch control valve 
unit 158, respectively. The fluid-pressure valve unit 156 comprises a 
valve body 160 formed with a generally cylindrical valve chamber 162 which 
is closed at one axial end by a plug member constituted by a bolt 164 
screwed into the valve body 160 and which communicates at the other end 
with the branch passageway 152. The valve body 160 is further formed with 
first and second drain ports 166 and 168 leading from the valve chamber 
162 and communicating with passageways which terminate in the fluid 
reservoir 148. The first drain port 166 is located in the vicinity of the 
axial end of the valve chamber 162 open to the branch passageway 152, 
while the second drain port 168 is constantly open to a longitudinally 
intermediate portion of the valve chamber 162. Within the valve chamber 
162 is mounted a generally cylindrical valve member 170 which has formed 
at one axial end thereof an axial projection 172 protruding toward the 
axial end of the valve chamber 162 open to the branch passageway 152, the 
valve member 170 further having a cylindrical concavity which is open at 
the axial end of the valve member opposite to the above mentioned axial 
projection 172. The valve member 170 is axially slidable within the valve 
chamber 162 and, thus, opens up or closes the first drain port 166 
depending upon the axial position of the valve member 170 within the valve 
chamber 162. The valve member 170 is urged to axially move in a direction 
to close the first drain port 166 by suitable biasing means such as a 
preloaded helical compression spring 174 which is seated at one end on the 
end face of the bolt 164 and at the other end on the bottom face of the 
concavity in the valve member 170. When the oil pump 136' is operative and 
delivers a fluid under pressure to the branch passageway 152, a fluid 
pressure acts on the valve member 170 and urges the valve member 170 to 
axially move in a direction to open up the first drain port 166 against 
the opposing force of the compression spring 174. When, thus, the fluid 
pressure acting on the valve member 170 is higher than a predetermined 
level which is dictated by the relationship between the cross sectional 
area of the valve member 170 and the force of the compression spring 174, 
the force resulting from the fluid pressure acting on the valve member 170 
overcomes the force of the compression spring 174 and causes the valve 
member 170 to axially move to a position at least partially opening up the 
first drain port 166 for a allowing the fluid to be discharged at a 
limited rate from the valve chamber 162 into the drain port 166. When the 
fluid pressure acting on the valve member 170 is thus diminished and 
reaches the predetermined level, the force resulting from such a fluid 
pressure is equalized with the opposing force of the compression spring 
174 so that the valve member 174 is held in an equilibrium axial position 
within the valve chamber 162. The fluid pressure delivered from the oil 
pump 136' into the fluid outlet passageway 150 and the branch passageways 
152 and 154 is in this fashion maintained at a level not higher than the 
above mentioned predetermined level. 
On the other hand, the clutch control valve unit 158 comprises a valve body 
176 formed with an elongated valve chamber 178 extending between end faces 
179a and 179b, the end face 179a being formed by an internal surface 
portion of the valve body 176. The valve body 176 is further formed with a 
fluid inlet port 180, first and second fluid outlet ports 182 and 184, a 
control port 186, and first and second drain ports 188 and 190. The fluid 
inlet port 180 is in constant communication with the branch passageway 
154, while the first and second fluid outlet ports 182 and 184 are in 
constant communication with the previously described first and second 
fluid passageways 140 and 142 in the torque converter and clutch assembly 
10 through passageways 192 and 194, respectively. The control port 186 
communicates through a flow restriction or orifice 196 with a bypass 
passageway 198 leading from the fluid inlet port 180. The drain ports 188 
and 190 are in communication with the fluid reservoir 148. The control 
port 186 and the second drain port 190 is located at the axial ends of the 
valve chamber 162, while the first drain port 188, first fluid outlet port 
182, fluid inlet port 180 and second fluid outlet port 184 are arranged in 
this sequence away from the control port 186 toward the second drain port 
190 as shown. Within the valve chamber 178 is mounted a valve spool 200 
having first, second and third lands 202, 204 and 206 which are arranged 
in this sequence away from one end face 179a of the valve chamber 178 
toward the other end face 179b and which have equal cross sectional areas. 
The lands 202, 204 and 206 are axially spaced apart from each other and 
form a first circumferential groove 208 between the first and second lands 
202 and 204 and a second circumferential groove 210 between the second and 
third lands 204 and 206. The valve spool 200 further has first and second 
axial projections 212 and 214 protruding from the outer end faces of the 
first and third lands 202 and 206, respectively, toward the end faces 179a 
and 179b, respectively, of the valve chamber 178. The valve spool 200 thus 
configured is axially slidable within the valve chamber 178 between a 
first axial position providing communication between the fluid inlet port 
180 and the first fluid outlet port 182 through the first circumferential 
groove 208 in the valve spool 200 and between the second fluid outlet port 
184 and the second drain port 190 as indicated by the upper half of the 
valve spool 200 in FIG. 2 and a second axial position providing 
communication between the fluid inlet port 180 and the second fluid outlet 
port 184 through the first circumferential groove 208 in the valve spool 
200 and between the first fluid outlet port 182 and the first drain port 
188 through the second circumferential groove 210 in the valve spool 200 
as indicated by the lower half of the valve spool 200. When the valve 
spool 200 is in the first axial position thereof, the second axial 
projection 214 of the valve spool has its end face in close contact with 
the end face 179b of the valve chamber 178. Likewise, when the valve spool 
200 is in the second axial position thereof, the first axial projection of 
the valve spool has its end face in close contact with the end face 179a 
of the valve chamber 178. The valve spool 200 is urged to move toward the 
first axial position thereof by suitable biasing means such as a preloaded 
helical compression spring 216 which is seated at one end on the outer end 
face of the first land 202 of the valve spool 200 and at the other end on 
the end face 179a of the valve chamber 178. 
The end face 179b defining one axial end of the valve chamber 178 is formed 
by a plug member 218 closely fitted to the valve body 176 so that the 
valve chamber 178 has a variable-volume end portion 178a between the end 
face 179b of the plug member 218 and the outer end face of the third land 
206 of the valve spool 200. The plug member 218 is formed with a nozzle 
218a which is open at one end to the variable-volume end portion 178a of 
the valve chamber 178 and at the other end to a fluid discharge port 220. 
The nozzle 218a has a cross sectional area which is sufficiently larger 
than the cross sectional area of the orifice 196 between the control port 
186 and the bypass passageway 198. A solenoid operated valve actuator 222 
has a plunger 223 axially projecting toward the outer end of the nozzle 
218a. Though not shown in the drawings, the solenoid operated valve 
actuator 222 is constructed and arranged in such a manner that the plunger 
223 thereof is moved forwardly and closes the outer end of the nozzle 218a 
at the leading end of the plunger 223 when the valve actuator 222 is 
energized. The plunger 223 is biased to move away from the outer end of 
the nozzle 218a so that the nozzle 218a is open when the solenoid operated 
valve actuator 222 is de-energized. 
When, thus, the solenoid operated valve actuator 222 remains de-energized, 
the nozzle 218a in the plug member 218 is kept open and provides 
communication between the variable-volume end portion 178a of the valve 
chamber 178 and the fluid discharge port 220 through the nozzle 218a. The 
nozzle 218a being sufficiently larger in cross sectional area than the 
orifice 196, the fluid entering the end portion 178a of the valve chamber 
178 through the orifice is discharged to the fluid discharge port 220 
through the nozzle 218a so that there is no fluid pressure developed in 
the end portion 178a of the valve chamber 178. The valve spool 200 is 
therefore held in the previously described first axial position thereof by 
the force of the compression spring 216 and establishes communication 
between the fluid inlet port 180 and the first fluid outlet port 182 
through the first circumferential groove 208 in the valve spool 200 and 
between the second fluid outlet port 184 and the second drain port 190 as 
indicated by the upper half of the valve spool 200 in FIG. 2. Under these 
conditions, the fluid delivered from the oil pump 136' to the fluid inlet 
port 180 through the branch passageway 154 is passed through the first 
fluid outlet port 182 of the valve unit 158 to the passageway 192 and from 
the passageway 192 to the first variable-volume chamber 38 within the 
torque converter torus cover 34 through the first fluid passageway 138 
formed between the stator support hollow shaft 42 and the pump support 
sleeve 138 of the torque converter and clutch assembly 10. The clutch unit 
26 is thus held in the coupled condition by the fluid pressure which acts 
on the front face of the clutch piston 46 as previously described in 
detail. When, conversely, the solenoid operated valve actuator 222 is 
energized and accordingly the plunger 223 thereof is in an axial position 
closing the outer end of the nozzle 218a in the plug member 218 so that a 
fluid pressure is developed in the end portion 178a of the valve chamber 
178 by the fluid entering the end portion 178a through the bypass 
passageway 198 and the orifice 196. The fluid pressure thus acting on the 
valve spool 200 from the end portion 178a of the valve chamber 178 causes 
the valve spool 200 to axially move away from the end face 179b of the 
plug member 218 against the opposing force of the compression spring 216 
and finally assumes the previously mentioned second axial position 
providing communication between the fluid inlet port 180 and the second 
fluid outlet port 184 and between the first fluid outlet port 182 and the 
first drain port 188. The fluid which has been delivered into the first 
variable-volume chamber 38 within the torque converter torus cover 34 
through the first fluid passageway 140 between the turbine support hollow 
shaft 42 and the pump support sleeve 138 is now discharged into the fluid 
reservoir 148 through the passageway 192 and the first drain port 188 and 
instead a fluid pressure is developed in the second variable-volume 
chamber 40 within the clutch housing 36 through the second fluid 
passageway 142 between the transmission input shaft 16 and the stator 
support hollow shaft 42. The clutch unit 26 is therefore caused to 
uncouple by the fluid pressure thus acting on the rear face of the clutch 
piston 46. The clutch unit 26 is in these manners uncoupled and coupled 
when the solenoid operated valve actuator 222 is energized and 
de-energized, respectively. 
The present invention is directed at an electric switch apparatus adapted 
to be incorporated into an electric circuit arrangement to energize and 
de-energize the solenoid operated valve actuator 222 in response to the 
movement of the manually operated gearshift lever 100 (FIG. 1A) to be 
moved when a shift is to be made in the transmission gear mechanism. 
In the embodiment of the present invention to be hereinafter described with 
reference to FIGS. 3 to 8 of the drawings, such a switch apparatus is 
shown comprising a first switch assembly Sa which is responsive to the 
movement of the gearshift lever 100 in the fore-and-aft directions B.sub.1 
and B.sub.2 thereof, viz., the rotational motion of the striking rod 92 
(FIG. 1A) in the directions b.sub.1 and b.sub.2 about the center axis 
thereof and a second switch assembly Sb which is responsive to the 
movement of the gearshift lever 100 in the lateral directions A.sub.1 and 
A.sub.2 thereof, viz., the movement of the striking rod 92 in the 
directions a.sub.1 and a.sub.2 thereof. 
Referring to FIG. 3, the first switch assembly Sa is arranged in 
conjunction with the knob 102 on the manually operated gearshift lever 
100. The knob 102 is formed of an electrically nonconductive material and 
has a concavity 224 which is open at the lower end of the knob 102 having 
an internal annular protrusion 226 defining at the lower end of the 
concavity 224 an opening through which the gearshift lever 100 axially 
projects into the concavity 224. The knob 102 further has a conical 
internal surface portion 230 defining the innermost closed end of the 
concavity 224 and having a vertex in close proximity the leading end of 
the gearshift lever 100. The gearshift lever 100 in turn has formed in its 
leading end portion an elongated bore 232 which is open at the extreme end 
of the gearshift lever 100, viz., in close proximity to the vertex of the 
conical internal surface portion 230 of the knob 102. A rigid ball 234 is 
received on the conical internal surface portion 230 of the knob 102 and 
is forced against the surface portion 230 by means of a preloaded helical 
compression spring 236 which is accommodated in the bore 232 in the 
gearshift lever 100 and which is seated at one end on the ball 234 whereby 
the knob 102 is urged to hold a position having the ball 234 situated at 
the vertex of the conical internal surface portion 230 of the knob 102 as 
shown, the particular position being herein referred to as the neutral 
position of the knob 102. The knob 102 has securely mounted on its 
internal side surface portion first and second electrical contact elements 
238 and 238' which are spaced apart from each other across the leading end 
portion of the gearshift lever 100 in the fore-and-aft directions in which 
the gearshift lever 100 is to be moved. When the knob 102 is moved for 
rocking motions about the center axis of the pivotal pin 228, the contact 
elements 238 and 238' on the knob 102 are moved relative to the gearshift 
lever 100 and thus constitute movable contact elements. First and second 
stationary contact elements 240 and 240' extend from the internal annular 
protrusion 226 of the knob 102 into the concavity 224 and have their 
leading end portions located in proximity to the first and second movable 
contact elements 238 and 238', respectively 224 in the knob 102. These 
stationary contact elements 240 and 240' are slightly movable with respect 
to the gearshift lever 100 when the knob 102 is moved for rocking motions 
about the center axis of the pivotal pin 228. Such movements of the 
contact elements 240 and 240' are, however, negligible as compared with 
the amounts of displacement of the movable contact elements 238 and 238' 
and, for this reason, the contact elements 240 and 240' are herein denoted 
as the stationary contact elements for brevity of description. The first 
and second stationary contact elements 240 and 240' are located in 
conjunction with the movable contact elements 238 and 238' in such a 
manner that the first movable contact element is brought into contact with 
the first stationary contact element 240 when the knob 102 is moved to 
rock in one lateral direction B.sub.1 and, likewise, the second movable 
contact element 238' is brought into contact with the second stationary 
contact element 240' when the knob 102 is moved to rock in the other 
lateral direction B.sub.2 about the axis of the pin 238. When the knob 102 
is held in the previously mentioned neutral position thereof, the movable 
contact elements 238 and 238' are separate from the stationary contact 
elements 240 and 240', respectively, as shown. The first movable and 
stationary contact elements 238 and 240 constitute, in combination, 
normally-open first switch means S.sub.1 and, likewise, the second movable 
and stationary contact elements 238' and 240' constitute, in combination, 
normally-open second switch means S.sub.2. The first switch assembly Sa 
illustrated in FIG. 3 is thus essentially composed of the normally-open 
first and second switch means S.sub.1 and S.sub.2 which are adapted to be 
closed when the knob 102 on the manually operated gearshift lever 100 is 
moved in the fore-and-aft directions B.sub.1 and B.sub.2, respectively. 
The movable contact elements 238 and 238' are connected to lead wires 242 
and 242', respectively, for connection to a power source (not shown) while 
the stationary contact elements 240 and 240' are grounded by lead wires 
244 and 244', respectively. 
Turning to FIGS. 4 and 5 of the drawings, the second switch assembly Sb is 
arranged in conjunction with the striking rod 92 forming part of the 
mechanical linkage intervening between the manually operated gearshift 
lever 100 and the transmission gear mechanism 12 (FIG. 1A) and largely 
comprises a shaft 246 rotatable with the striking rod 92, a stationary 
shaft support member 248 supporting the shaft 246, a rotatable contact 
support member 250 keyed or splined to the shaft 246, and a stationary 
contact support member 252 which is secured to the shaft support member 
248 with the rotatable contact support member 250 positioned between the 
stationary shaft and contact support members 248 and 252. As will be 
better seen from FIG. 5, the stationary shaft support member 248 is 
fixedly mounted on the transmission casing C by suitable fastening means 
such as a bolt 254 and is formed with an axial bore 256 through which the 
shaft 246 is mounted on the support member 248 in a manner to be rotatable 
relative to the support member 248 about its center axis which is 
substantially in line with the axis of rotation of the striking rod 92 
extending through the bore 97 in the transmission casing C. The stationary 
shaft support member 248 has a generally cylindrical projection 258 
radially outwardly spaced apart from the outer peripheral surface of an 
intermediate axial portion of the shaft 246 and forms an annular gap 
between the outer peripheral surface of the shaft 246 and the inner 
peripheral surface of the cylindrical projection 258. As will be seen from 
FIG. 4, the cylindrical projection 258 has an axial slot slightly 
elongated substantially in parallel with the axis of rotation of the shaft 
246 and forming two edge portions which are slightly spaced apart from 
each other in the circumferential direction of the projection 258. The 
stationary shaft support member 248 is further formed with a generally 
semicircular recess 260 containing the cylindrical projection 258 therein. 
The rotatable contact support member 250 is constructed of an electrically 
non-conductive material such as a rigid plastic and has a generally 
frusto-conical portion 262 keyed or splined to the shaft 246 and a 
generally sector-shaped portion 264 positioned within the generally 
semicircular recess 260 in the stationary shaft support member 248. The 
generally semicircular recess 260 in the shaft support member 248 is so 
shaped as to be capable of sufficiently accommodating therewithin the 
rotational movement of the sector-shaped portion 264 of the rotatable 
contact support member 250 which is to be moved for rotation about the 
center axis of the shaft 246 when the striking rod 92 is driven to turn 
between the limit rotational positions thereof about the center axis of 
the rod 92 in the directions of the arrowheads b.sub.1 and b.sub.2. The 
rotatable contact support member 250 has formed in its sector-shaped 
portion 264 four radial grooves extending in radial directions about the 
center axis of the shaft 246 and spaced apart from each other in a 
circumferential direction of the contact support member 250 as commonly 
indicated at 266 in FIG. 5. Four radial contact elements 268a, 268b, 268c 
and 268d are respectively received in these radial grooves 266 and are 
urged to protrude outwardly from the grooves in directions substantially 
parallel with the center axis of the shaft 246 by suitable biasing means 
such as a preloaded helical compression spring 270 which is seated at the 
bottom of each of the grooves 266 and which is partly received in a hole 
formed in each of the radial contact elements 268a, 268b, 268c and 268d, 
as shown in FIG. 5. When the rotatable contact support member 250 is 
driven for rotation about the center axis of the shaft 246, the radial 
contact elements 268a, 268b, 268c and 268d revolve around the center axis 
of the shaft 246 and will therefore be hereinafter referred to as movable 
contacts. The rotatable contact support member 250 is further formed with 
a recess 272 accommodating therewithin the previously described 
cylindrical projection 258 of the stationary shaft support member 248 and 
having a generally sector shaped portion 272a which has a center axis 
substantially coincident with the axis of rotation of the shaft 246 and 
which has two radial edges at the circumferential ends of the 
sector-shaped portion 272a as indicated by broken lines in FIG. 4. A 
helical torsion spring 274 having radially outwardly bent end portions 
274a and 274b is positioned, in coaxial relationship with the shaft 246, 
in the cylindrical gap between the outer peripheral surface of the shaft 
246 and the inner peripheral surface of the cylindrical projection 258 of 
the stationary shaft support member 248. The helical torsion spring 274 
has its radially outwardly bent end portions 274a and 274b received on the 
opposite edges of the previously mentioned axial slot in the cylindrical 
projection 258 of the stationary shaft support member 248 and located 
within the sector-shaped portion 274a of the recess 272 in the rotatable 
contact support member 250. Thus, the torsion spring 274 is effective to 
urge the rotatable contact support member 250 to stay in a predetermined 
fiducial angular position about the center axis of the shaft 246 with 
respect to the stationary shaft and contact support members 248 and 252 so 
that, when the rotatable contact support member 250 is forced to rotate in 
either direction away from such a fiducial angular position about the 
center axis of the shaft 246, the contact support member 250 is urged to 
turn in a reverse direction toward the fiducial angular position by the 
force of the torsion spring 274. The rotatable contact support member 250 
shown in FIG. 4 is assumed to be held in the above mentioned fiducial 
angular position thereof. 
The stationary contact support member 252 is also constructed of an 
electrically non-conductive material such as a rigid plastic and is 
fixedly connected to the stationary shaft support member 248 by suitable 
fastening means such as bolts 275. The stationary contact support member 
252 has formed in its wall portion facing the above described movable 
contact elements 268a to 268d in the rotatable contact support member 250 
a first set of arcuate grooves 278 which are radially inwardly spaced 
apart from the first set of arcuate grooves 276 about the center axis of 
the shaft 246 as will be seen from FIG. 5. The first set of arcuate 
grooves 276 has closely fitted therein a first set of arcuate contact 
elements 280a, 280b, 280c and 280d which are arcuately curved about the 
center axis of the shaft 246 and which are spaced apart from each other in 
circumferential directions about the center axis of the shaft 246. 
Likewise, the second set of arcuate grooves 278 has closely fitted therein 
a second set of arcuate contact elements 282a, 282b, 282c and 282d which 
are arranged similarly to the first set of arcuate contact elements 280a 
to 280d and which are radially inwardly spaced apart from the contact 
elements 280a, 280b, 280c and 280d, respectively. The four pairs of 
contact elements 280a and 282a, 280b and 282b, 280c and 282c, and 280d and 
282d thus mounted on the stationary contact support elements constitute 
four sets of stationary contacts and are located to be in conjunction with 
the previously mentioned four movable contacts 268a, 268b, 268c and 268d, 
respectively, on the rotatable contact support member 250. More 
specifically, the movable contacts 268a to 268d on the rotatable contact 
support member 250 and the movable contacts 280a and 282a to 280d to 282d 
on the stationary contact support member 252 are located in such a manner 
that, when the rotatable contact support member 250 is in the previously 
mentioned fiducial angular position about the center axis of the shaft 246 
by the force of the torsion spring 274, the movable contacts 268a, 268b, 
268c and 268d are located at predetermined fiducial points of their 
respectively associated stationary contacts 280a and 282a, 280b and 282b, 
280c and 282c, and 280d and 282d, respectively, as shown in FIG. 4. The 
movable contacts 268a to 268d being urged to protrude outwardly from the 
grooves 266 in the rotatable contact support member 250 by means of the 
preloaded helical compression springs 270 as previously described, each of 
the movable contacts 268a, 268b, 268c and 268d is forced to be in contact 
with each of the combinations of the stationary contacts 280a and 282a, 
280b and 282b, 280c and 282c, and 280d and 282d, respectively, when the 
rotational contact support member 250 is in an angular position having 
each of the movable contacts located within the coverage of the 
combination of the associated stationary contacts. In the second switch 
assembly Sb of the apparatus embodying the present invention, the 
combination of the movable contact 268a and stationary contacts 280a and 
282a the combination of the movable contact 268b and stationary contacts 
280b and 282b, the combination of the movable contact 268c and stationary 
contacts 280c and 282c, and the combination of the movable contact 268d 
and stationary contacts 280d and 282d constitute third, fourth, fifth and 
sixths switch means S.sub.3, S.sub.4, S.sub.5 and S.sub.6, respectively, 
of the switch apparatus. When the movable contact of each of these switch 
means S.sub.3, S.sub.4, S.sub.5 and S.sub.6 is in contact with the two 
stationary contacts of the switch means, there is provided electrical 
connection between the stationary contacts through the movable contact and 
thus the particular switch means assumes a closed condition. The 
individual contact elements on the stationary contact support member 252 
are connected to lead wires 284 which are bundled in a protective sheath 
286, as shown in 4. Designated by reference numeral 288 is a strip of 
sealing compound which is attached to the outer face of the stationary 
contact support member 252 for protecting the contact elements on the 
member 252 from electrolytic corrosion. 
On the other hand, the striking rod 92 has an axial bore 290 which is open 
toward the shaft 246 passed through the bore 256 in the stationary contact 
support member 248 and an axially elongated slot 292 which is open at the 
extreme end of the striking rod 92 and which has a circumferentially 
enlarged end portion 292a as indicated by broken lines in FIG. 6A. The 
shaft 246 extending in line with the striking rod 92 thus configured has a 
cylindrical end portion 294 projecting into the axial bore 290 in the 
striking rod 92 and a generally wedge-shaped projection 296 axially 
protruding from the end portion 294 into the elongated slot 292 in the 
striking rod 92. While the shaft 246 per se is axially fixed relative to 
the transmission casing C, the striking rod 92 is axially movable relative 
to the transmission casing C and according to the shaft 246 with the 
cylindrical end portion 294 of the shaft 246 kept received in the bore 290 
and with the wedge-shaped projection 296 of the shaft 246 kept located 
within the elongated slot 292. When, thus, the transmission gearshift 
lever 100 is manually moved in the directions A.sub.1 and A.sub.2 
accordingly the striking rod 92 is axially moved in the directions of the 
arrowheads a.sub.1 and a.sub.2 as indicated in FIG. 6B, the wedge-shaped 
projection 296 of the shaft 246 assumes different axial positions relative 
to the striking rod 92 as indicated by 296, 296' and 296" in FIG. 6A. 
When, more particularly, the transmission gearshift lever 100 is in the 
position to select the low, direct-drive or overdrive gear position "L", 
"D" or "OD", the wedge-shaped projection 296 of the shaft 246 is located 
within the reduced portion of the elongated slot 292 in the striking rod 
92 as indicated by 296' or 296" in FIG. 6A so that the shaft 246 is 
rotatable with the striking rod 92. When, on the other hand, the gearshift 
lever 100 is in the position to select the reverse-drive or parking gear 
position "R" or "P", then the wedge-shaped projection 296 of the shaft 246 
is located within the enlarged end portion 292a of the slot 292 in the 
striking rod 92 as indicated by full lines in FIG. 6A so that the 
wedge-shaped projection 296 is not capable of engaging one of the 
circumferentially spaced apart axial edge portions forming the enlarged 
end portion 292a of the slot 292 in the striking rod 92. The end portion 
292a of the elongated slot 292 in the striking rod 92 is circumferentially 
enlarged in a direction in which the striking rod 92 is to be turned in 
the sirection of the arrowhead b.sub.1 about its axis with the 
transmission gearshift lever 100 moved in the direction of the arrowhead 
B.sub.1. When, thus, the transmission gearshift lever 100 is moved to 
select the parking gear position "P", the wedge-shaped projection 296 is 
disengaged from the strking rod 92 with the result that the movement of 
the transmission gearshift lever 100 from the neutral gear position "N" to 
the parking gear position "P" is not transmitted to the shaft 246. When, 
however, the transmission gearshift lever 100 is moved to the 
reverse-drive gear position "R", the wedge-shaped projection 296 of the 
shaft 246 is held in engagement with the striking rod 92 and is thus 
rotatable with the striking rod 92. The elongated slot 292 in the strking 
rod 92 and the wedge-shaped projection 296 of the shaft 246 are arranged 
so that the rotatable contact support member 250 carried by the shaft 100 
is in the previously mentioned fiducial angular position thereof when the 
transmission gearshift lever 100 is in the neutral gear position "N". 
FIG. 7 shows in the form of a bar graph an example of the schedules in 
accordance with which the third, fourth, fifth and sixths switch means 
S.sub.3, S.sub.4, S.sub.5 and S.sub.6 thus constructed and arranged in the 
second switch assembly Sb are to be open and closed responsive to the 
movement of the transmission gearshift lever 100 from the neutral position 
"N" to any of the low, direct-drive, overdrive, and reverse-drive gear 
positions "L", "D", "OD" and "R". In FIG. 7, the lengths of the bars from 
the line N indicate the central angles of the four pairs of contact 
elements 280a and 282a, 280b and 282b, 280c and 282c and 280d and 282d on 
the rotatable contact support member 250 from the predetermined fiducial 
points of the individual contact elements. In other words, the lengths of 
the bars from the line N are representative of the durations for which the 
third, fourth, fifth and sixth switch means S.sub.3, S.sub.4 , S.sub.5 and 
S.sub.6 incorporated in the second switch assembly Db remain closed when 
the transmission gearshift lever 100 is moved from the neutral gear 
position "N" to the low or reverse-drive gear position "L" or "R" in one 
fore-and-aft direction B.sub.1 thereof or to the direct-drive or overdrive 
gear position "D" or "OD" in the other lateral direction B.sub.2 thereof. 
The central angles indicated by W are the angles of rotation of the 
rotatable contact support member 250 which is turned about the center axis 
of the shaft 246 from the previously mentioned fiducial angular position 
thereof to an angular position achieved when the first or second 
synchronizer 80 or 82 is slid on the transmission mainshaft 52 by the 
striking rod 92 and is fully meshed with any of the gears 56, 58, 60 and 
62 (FIG. 1A). On the other hand, the central angles indicated by X are 
angles of rotation of the rotatable contact support member 250 which is 
turned about the center axis of the shaft 246 from the fiducial angular 
position thereof to an angular position having the first or second 
synchronizer 80 or 82 moved into a position initially producing a fully 
synchronized condition between the transmission mainshaft 52 and any of 
the gears 56, 58, 60 and 62 engaged by the synchronizer 80 or 82. The 
central angle indicated by Y is slightly larger than the central angle X 
but smaller than the central angle W, while the central angle indicated by 
Z is far smaller than the central angle X. The arcuate contact elements 
280a and 282a forming part of the third switch means S.sub.3 are so 
arranged as to have about the center axis of the shaft 246 a central angle 
W from their fiducial points in the direction of rotation of the rotatable 
contact support member 250 turned from its fiducial angular position about 
the center axis of the shaft 246 when the striking rod 92 is rotated in 
the direction of the arrowhead b.sub.1 about its center axis and a central 
angle Y from their fiducial points in the direction of rotation of the 
rotatable contact support member 250 turned from its difucial angular 
position about the center axis of the shaft 246 when the striking rod 92 
is rotated in the direction of the arrowhead b.sub.2 about its center 
axis. Thus, the third switch means S.sub.3 is adapted to be open when the 
transmission gearshift lever 100 moved from the neutral gear position "N" 
toward the low or reverse-drive gear position "L" or "R" reaches the 
particular gear position "L" or "R" having the first or second 
synchronizer 80 or 82 fully meshed with the mainshaft low or reverse-drive 
gear 58 or 62 in the transmission gear mechanism 12 or when the 
transmission gearshift lever 100 moved from the neutral gear position "N" 
toward the direct-drive or overdrive gear position "D" or "OD" reaches a 
position having the first or second synchronizer 80 or 82 moved past the 
position initially producing a fully synchronized condition between the 
transmission mainshaft 52 and the transmission main drive gear 56 or the 
mainshaft overdrive gear 60 but not yet fully meshed with the gear 56 or 
60. The arcuate contact elements 280b and 282b constituting the fourth 
switch means S.sub.4 are arranged in such a manner as to have central 
angles Y and W from their fiducial points in the directions of rotation of 
the rotatable contact support member 250 turned from its fiducial angular 
position about the center axis of the shaft 246 when the striking rod 92 
is rotated about its center axis in the directions of the arrowheads 
b.sub.1 and b.sub.2, respectively. The fourth switch means S.sub.4 is thus 
adapted to be open when the transmission gearshift lever 100 moved from 
the neutral gear position "N" toward the low or reverse-drive gear 
position "L" or "R" reaches a position having the first or second 
synchronizer 80 or 82 moved beyond the position initially producing a 
fully synchronized condition between the transmission mainshaft 52 and the 
mainshaft low or reverse-drive gear 58 or 62 but not yet fully meshed with 
the gear 58 or 62 or when the transmission gearshift lever 100 is moved 
from the neutral gear position "N" toward the direct-drive or overdrive 
gear position "D" or "OD" and reaches the particular gear position "D" or 
"OD" having the first or second synchronizer 80 or 82 fully meshed with 
the transmission main gear drive 56 or the mainshaft overdrive gear 60. 
The arcuate content elements 280c and 282c constituting the fifth switch 
means S.sub.5 are arranged to have a central angle X from their fiducial 
points in each of the directions of rotation of the rotatable contact 
support member 250 turned from its fiducial angular position about the 
center axis of the shaft 246 when the striking rod 92 is rotated about its 
center axis in each of the directions b.sub.1 and b.sub.2. The fifth 
switch means S.sub.4 is thus adapted to be open when the transmission 
gearshift lever 100 moved from the neutral gear position "N" toward any of 
the low, direct-drive, overdrive or reverse-drive gear position "L", "D", 
"OD" or "R" reaches a position having the first or second synchronizer 80 
or 82 moved into the position initially procuding a fully synchronized 
condition between the transmission mainshaft 52 and any of the gears 56, 
58, 60 or 62 in the transmission gear mechanism 12. The arcuate contact 
elements 280d and 282d constituting the sixth switch means S.sub.6 are 
arranged to have a central angle Z from their fiducial points in each of 
the directions of rotation of the rotatable contact support member 250 
turned from its fiducial angular position about the center axis of the 
shaft 246 when the striking rod 92 is turned in each of the directions of 
arrowheads b.sub.1 and b.sub.2. The sixth switch means S.sub.6 is thus 
permitted to remain closed when the transmission gearshift lever 100 is 
held in or slightly moved from the neutral gear position "N". 
FIG. 8 shows an electric circuit incorporating the first to sixth switch 
means S.sub.1 to S.sub.6 thus constructed and according in conjunction 
with the manually operated transmission gearshift lever 100. The first and 
second switch means S.sub.1 and S.sub.2 arranged within the knob 102 on 
the manually operated transmission gearshift lever 100 are connected in 
series with the above described third and fourth switch means S.sub.3 and 
S.sub.4, respectively. The series combination of the first and third 
switch means S.sub.1 and S.sub.3 and the series combination of the second 
and fourth switch means S.sub.2 and S.sub.4 are connected in parallel with 
the fifth switch means S.sub.5 to the positive terminal of a d.c. power 
source 300 through the solenoid coil (not shown) of the previously 
described solenoid operated valve actuator 222 and preferably across a 
third switch assembly 302 which may be constituted by the ignition switch 
of the engine. If desired, a fuse 304 may be connected between the valve 
actuator 222 and the third switch assembly 302 as shown. The third switch 
assembly 302 consists of a first switch element 302a connected between the 
valve actuator 222 and the power source 300 and a second switch element 
302b which is connected between the power source 300 and the coil (not 
shown) of a cranking motor 306 for the engine. The switch assembly 302 is 
adapted to close its first and second switch elements 302a and 302b 
sequentially in response to first and second closing actions, 
respectively, to be exerted on the switch assembly 302. 
Operation of the switch apparatus thus constructed and arranged in 
accordance with the present invention will be hereinafter described with 
reference in FIGS. 1A to 8. 
When the manually operated gearshift lever 100 is held in the neutral gear 
position "N", all of the third to sixth switch means S.sub.3 to S.sub.6 
are kept closed as will be understood from the schedules illustrated in 
FIG. 7. If, therefore, a first closing action is exerted on the third 
switch assembly 302, the first switch element 302a of the assembly 302 is 
closed. The fifth switch means S.sub.5 being kept closed, the solenoid 
coil of the valve actuator 222 is energized from the power source 300 
through the fifth switch means S.sub.5 and the first switch element 302a 
of the third switch assembly 302 even though the first and second switch 
means S.sub.1 and S.sub.2 on the knob 102 of the transmission gearshift 
lever 100 may be kept or, in other words, the transmission gearshift lever 
100 may be kept released. The solenoid operated valve actuator 222 being 
thus energized from the power source 300, the nozzle 218a in the plug 
member 218 in the clutch control valve unit 158 is closed by the plunger 
222a of the valve actuator 222 with the result that the valve spool 200 of 
the clutch control valve unit 158 is moved into the second axial position 
thereof as indicated by the lower half of the valve spool 200 in FIG. 2, 
thereby causing a fluid pressure to be developed in the second fluid 
passageway 142 between the transmission input shaft 16 and the stator 
support hollow shaft 42 of the torque conveter and clutch assembly 10. 
With a fluid pressure thus developed in the second variable-volume chamber 
40 within the clutch housing 36, the clutch piston 46 is moved toward the 
rear face of the torque converter torus cover 34 and as a consequence the 
clutch unit 26 is caused to uncouple. When a second closing action is 
exerted on the switch assembly 302 shown in FIG. 8, the second switch 
element 302b is closed and enables the cranking motor 306 for the engine 
to be energized from the power source 300 through the second switch 
element 302b of the switch assembly 302 and the sixth switch means S.sub.6 
which is closed with the transmission gearshift lever 100 held in the 
neutral gear position "N". The engine being thus started, however, the 
driving torque is not transmitted to the transmission input shaft 16 
because the clutch unit 26 is maintained in the uncoupled condition. 
When, under these conditions, the transmission gearshift lever 100 is 
manually moved in one fore-and-aft direction B.sub.1 from the neutral gear 
position "N" toward the low or reverse-drive gear position "L" or "R", the 
rotatable contact support member 250 of the second switch assembly Sb 
shown in FIGS. 4 and 5 is driven by the striking rod 92 to turn in one 
direction from the previously mentioned fiducial angular position thereof 
about the center axis of the shaft 246. At an instant the rotatable 
contact support member 250 reaches the rotational position angularly 
displaced through the predetermined angle Z from the fiducial angular 
position thereof, the radial contact element 268d on the contact support 
member 250 is brought out of contact with the associated arcuate contact 
elements 280d and 282d on the stationary contact support member 252 so 
that sixth switch means S.sub.6 constituted by the contact elements 268d, 
280d and 282d is made open and causes the cranking motor 306 for the 
engine to be de-energized. As the transmission gearshift lever 100 is 
further moved toward the low or reverse-drive gear position "L" or "R" and 
accordingly the rotatable contact support element 250 is further driven 
for rotation away from the fiducial angular position about the center axis 
of the shaft 246 and reaches the rotational position angularly displaced 
through the predetermined angle X from the fiducial angular position, the 
first or second synchronizer 80 or 82 being driven by the striking rod for 
mating engagement with the mainshaft low or reverse-drive gear 58 or 60, 
respectively, reaches the position capable of producing a fully 
synchronized condition between the transmission mainshaft 52 and the low 
or reverse-drive gear 58 or 60 (which under these conditions is still 
maintained at rest with the clutch unit 26 held uncoupled) and at the same 
time the radial contact element 268c on the rotatable contact support 
member 250 is brought out of contact with the associated arcuate contact 
elements 280c and 282c on the stationary contact support member 252. The 
fifth switch means S.sub.5 constituted by the contact elements 268c, 280c 
and 282c is now opened up. While the transmission gearshift lever 100 is 
being thus manipulated, the manipulative effort imparted to the knob 102 
on the gearshift lever 100 (FIG. 3) in the direction of the arrowhead 
B.sub.1 causes the movable contact element 230' on the knob 102 to be 
pressed onto the associated stationary contact element 240' within the 
cavity 224 in the knob 102 so that the second switch means S.sub.2 
constituted by the movable and stationary contact elements 238' and 240' 
is kept closed. After the rotatable contact support member 250 is turned 
through the angle X from the fiducial angular position thereof about the 
center axis of the shaft 246, therefore, electrical connection between the 
solenoid operated valve actuator 222 and the power source 300 (FIG. 8) is 
provided through the series combination of the second switch means S.sub.2 
and the fourth switch means S.sub.4 which is still kept closed for a short 
period of time after synchronism has been achieved between the 
transmission mainshaft 52 and the mainshaft low or reverse-drive gear 58 
or 62 by means of the first or second synchronizer 80 or 82, respectively. 
The solenoid operated valve actuator 222 is in this fashion kept energized 
and accordingly the clutch unit 26 is maintained in the uncoupled 
condition for a short period of time after rotatable contact support 
member 250 is moved beyond the rotational position which is angularly 
displaced through the angle X from the fiducial angular position about the 
center axis of the shaft 246. When the rotatable contact support member 
250 is further turned and reaches the rotational position angularly 
displaced through the predetermined angle Y from the fiducial angular 
position thereof about the center axis of the shaft 246, the radial 
contact element 268b on the rotatable contact support member 250 is 
brought out of contact with the associated arcuate contact elements 280b 
and 282b on the stationary contact support member 252. The fourth switch 
means S.sub.4 constituted by the contact elements 268b, 280b and 282b is 
thus opened up. Under these conditions, the third switch means S.sub.3 is 
still kept closed as will be understood from the schedules shown in 7 but 
the first switch means S.sub.1 mounted on the knob 102 on the transmission 
gearshift lever 100 is kept open in the ansence of a pressing force 
imparted to the knob 102 in the direction of the arrowhead B.sub.2 (FIG. 
3). Both of the series combination of the first and third switch means 
S.sub.1 and S.sub.3 and the series combination of the second and fourth 
switch means S.sub.2 and S.sub.4 being thus open, the solenoid operated 
valve actuator 222 is disconnected from the power source 300 and is 
accordingly energized. The plunger 222a of the valve actuator 222 (FIG. 2) 
is now allowed to retract from the position closing the nozzle 218a in the 
plug member 218 of the clutch control valve unit 158 so that the valve 
spool 200 in the unit 158 is moved into the first axial position thereof, 
thereby allowing the fluid to be discharged from the second 
variable-volume chamber 40 within the clutch housing 36 and building up a 
fluid pressure in the first variable-volume chamber 38 within the torque 
converter torus cover 38 through the first fluid passageway 140 between 
the stator support hollow shaft 42 and the transmission pump support 
sleeve 138. The clutch piston 46 is now moved to press the clutch disc web 
116 onto the clutch plates 118 and 118' (FIG. 2) and establishes driving 
connection from the turbine 30 of the torque converter 24 to the 
transmission input shaft 16 through the clutch unit 26 thus coupled. By 
the time the clutch unit 26 is thus coupled, the first or second 
synchronizer 80 or 82 is in mesh with the mainshaft low or reverse-drive 
gear 58 or 60, respectively, in the transmission gear mechanism 12. When 
the transmission gearshift lever 100 is moved into the low or 
reverse-drive gear position "L" or "R" and accordingly the first or second 
synchronizer 80 or 82 is fully meshed with the mainshaft low or 
reverse-drive gear 58 or 60, respectively, the radial contact element 268a 
on the rotatable contact support member 250 of the second switch assembly 
Sb is located at the extreme ends of the associated arcuate contact 
elements 280a and 282a on the stationary contact support member 252 so 
that the third switch means S.sub.3 constituted by the contact elements 
268a, 280a and 282a is kept closed. 
When the transmission gearshift lever 100 thus held in the low or 
reverse-drive gear position "L" or "R" is moved back to the neutral gear 
position "N", the first switch means S.sub.1 is closed with the movable 
contact element 238 pressed onto the stationary contact element 240 by the 
manipulative force imparted to the knob 102 on the transmission gearshift 
lever 100 in the direction of the arrowhead B.sub.2. The third switch 
means S.sub.3 having been kept closed, the solenoid operated valve 
actuator 222 is energized from the power source 300 and as a consequence 
the clutch unit 26 is uncoupled at the instant the first switch means 
S.sub.1 is closed. When the transmission gearshift lever 100 is thereafter 
released from the manipulative effort, the valve actuator 222 is kept 
energized and accordingly the clutch unit 26 is maintained in the 
uncoupled condition by means of the fifth switch means S.sub.5 which is 
kept closed when the transmission gearshift lever 100 is held in or in the 
vicinity of the neutral gear position "N" as will be seen from FIG. 7. 
When the transmission gearshift lever 100 is then moved to select the 
direct-drive or overdrive gear position "D" or "OD", the knob 102 on the 
gearshift lever 100 is pressed in the direction of the arrowhead B.sub.2, 
electrical connection is provided between the solenoid-operated valve 
actuator 222 and the power source 300 not only through the fifth switch 
means S.sub.5 but through the series combination of the first and third 
switch means S.sub.1 and S.sub.3 until the rotatable contact support 
member 250 driven by the striking rod 92 for rotation in the direction of 
the arrow b.sub.2 about the center axis of the shaft 246 is turned through 
the predetermined angle X from the fiducial angular position thereof and 
accordingly the first or second synchronizer 80 or 82 reaches the position 
initially producing a synchronized condition between the transmission 
mainshaft 52 and the transmission main drive gear 56 or the mainshaft 
overdrive gear 60, respectively, in the transmission gear mechanism 12. 
When the rotatable contact support member 250 is further turned about the 
center axis of the shaft 246, the fifth switch means S.sub.5 is opened up 
so that the solenoid operated valve actuator 222 is kept energized from 
the power source 300 through the series combination of the first and thrid 
switch means S.sub.1 and S.sub.3 until the rotatable contact support 
member 250 reaches rotational position which is angularly displaced 
through the predetermined angle Y frm the fiducial angular position 
thereof. When such a rotational position is reached by the rotatable 
contact support member 250, the third switch means S.sub.3 is made open so 
that, with the second switch means S.sub.2 kept open although the fourth 
switch means S.sub.4 still kept closed, the solenoid operated valve 
actuator 222 is disconnected from the power source 300 and is accordingly 
de-energized. The clutch unit 26 is therefore allowed to resume the 
coupled condition so that the driving torque transmitted from the turbine 
30 of the torque converter 24 to the transmission input shaft 16 through 
the clutch unit 26 is carried over to the transmission input shaft 52 
through the transmittion maindrive shaft 56 or the mainshaft overdrive 
gear 60 with which the transmission mainshaft 52 has been fully 
synchronized by the action of the first or second synchronizer 80 or 82, 
respectively. When the transmission gearshift lever 100 reaches the 
direct-drive or overdrive gear position "D" or "OD", the first or second 
synchronizer 80 or 82 is fully meshed with the transmission main drive 
gear 56 or the mainshaft overdrive gear 60. 
When the transmission gearshift lever 100 is thereafter moved back from the 
direct-drive or overdrive gear position "D" or "OD" toward the neutral 
gear position "N", the knob 102 on the gearshift lever 100 is subjected to 
a manipulative force in the direction of the arrow B.sub.1 and as a 
consequence the second switch means S.sub.2 is caused to close. The fourth 
switch means S.sub.4 having been kept closed, electrical connection is 
established between the solenoid operated valve actuator 222 and the power 
source 300 through the series combination of the second and fourth switch 
means S.sub.2 and S.sub.4 and as a consequence the clutch unit 26 is 
caused to uncouple as soon as the knob 102 on the transmission gearshift 
lever 100 is gripped. When the gearshift lever 100 is thereafter released 
from the manipulative effort in the direction of the arrowhead B.sub.1, 
the second switch means S.sub.2 is opened up but the electrical connection 
between the solenoid operated valve actuator 222 and the power source 300 
is maintained through the fifth switch means S.sub.5. 
When the transmission gearshift lever 100 is moved in the direction 
indicated by the arrowhead B.sub.2 for shifting to the parking gear 
position "P", the wedge-shaped axial projection 296 of the end portion 294 
of the shaft 246 aligned with the striking rod 92 is located within the 
laterally enlarged portion 292a of the axial slot 292 in the striking rod 
292 as shown by full lines in FIG. 6A. If, therefore, the striking rod 92 
is turned in the direction of the arrowhead b.sub.2 by the transmission 
gearshift lever 100 moved from the neutral gear position "N" to the 
parking gear position "P", the axial projection 296 is disengaged from the 
striking rod 92 so that the rotation of the sriking rod 92 about the 
center axis thereof is not transmitted to the shaft 246 of the second 
switch assembly Sb, which accordingly is maintained in the condition 
having the rotatable contact support member 250 held in the fiducial 
angular position thereof as in the case where the transmission gearshift 
lever 100 is in the neutral gear position "N". When the transmission 
gearshift lever 100 is held in the parking gear position "P", all of the 
switch means S.sub.3, S.sub.4, S.sub.5 and S.sub.6 are kept closed and, 
for this reason, the cranking motor 306 can be energized through the sixth 
switch means S.sub.6 simply by closing the second switch element 302b of 
the third switch assembly 302. 
From the foregoing description it will have been appreciated that the 
electric switch apparatus provided by the present invention has the 
following major advantages: 
(1) The second switch assembly Sb can be easily installed on the 
transmission casing C in such a manner that the contact elements 
constituting the third, fourth and fifth switch means S.sub.3, S.sub.4 and 
S.sub.5 are operable accurately in conjuntion with the various gear 
positions of the transmission gearshift lever 100. Furthermore, there is 
no need of adjusting the positional relationship among the switch means 
S.sub.3, S.sub.4 and S.sub.4 during assemblage of the second switch 
apparatus Sb. 
(2) The switch means S.sub.6 for energizing the cranking motor 306 for the 
engine is permitted to close only when the transmission gearshif lever 100 
is in the neutral or parking gear position "N" or "P". Incorporation of 
such switch means S.sub.6 into the engine starting system will provide 
ease of inspection and servicing of the system because the system need be 
checked for the particular switch means alone. 
(3) The engagement between the striking rod 92 and the shaft 246 of the 
second switch assembly Sb being such that the rotatable contact support 
member 250 is enabled to remain in the fiducial angular position thereof 
when the transmission gearshift lever 100 is not only in the neutral gear 
position "N" but in the parking gear position "P", the contact elements 
268a to 268d on the rotatable contact support member 250 and the contact 
elements 280a to 280d and 282a to 282d on the stationary contact support 
member 252 can be arranged in circumferential directions and on fixed 
planes, thereby providing simplicity of construction.