Hydraulically operative clutch type transmission

A hydraulically operative clutch type transmission especially for industrial and loading vehicles comprises a casing accommodating shift gear mechanism therein, a housing connected to the casing, an input shaft journalled to the housing, a main shaft connected to the input shaft, a gearing member, a hydraulically operative clutch device which comprises a clutch drum connected to the main shaft and a clutch hub connected to the gearing member, a washer plate interposed between the gearing member and sleeve end of the clutch drum, the main shaft including a large diameter portion having a notch with a plain surface, and a small diameter portion, a gear member of the gearing member being rotatably supported on the large diameter portion, the clutch drum mounted on the small diameter portion, and the washer plate including a fasting portion which is engaged with the notch.

BACKGROUND OF THE INVENTION 
1. Field of the Invention 
The present invention relates to a hydraulically operative clutch type 
transmission especially for industrial and loading vehicles, and more 
particularly to an improvement in a hydraulically operative clutch type 
transmission having a gearing means actuated by a hydraulically operative 
clutch device. 
2. Description of the Prior Art 
Conventionally, hydraulically operative clutch type transmissions mentioned 
above have been proposed as disclosed in, for example, the U.S. Pat. No. 
3,254,541 issued on June 7, 1966. In such prior transmissions, however, a 
clutch drum of a hydraulically operative clutch device may be secured to a 
main shaft and, therefore, the clutch device can not move on the main 
shaft in its axial direction. Thus, the main shaft receives an undesirable 
thrust force which is caused to be generated by the operation of the 
clutch device. 
SUMMARY OF THE INVENTION 
It is, therefore, an object of the present invention to provide a new and 
improved hydraulically operative clutch type transmission which obviates 
the prior disadvantage mentioned above. 
It is another object of the present invention to provide a new and improved 
hydraulically operative clutch type transmission which is easy in 
assembling and is simple in construction. 
According to the present invention, a hydraulically operative clutch type 
transmission comprises a casing accommodating a shift gear mechanism 
therein, a housing connected to the casing, an input shaft journalled to 
the housing, a main shaft connected to the input shaft at one end thereof 
and journalled to the casing, a hydraulically operative clutch device 
mounted on the main shaft, a gearing member for transmitting power, and a 
washer plate interposed between the gearing member and sleeve end of a 
clutch drum of the hydraulically operative clutch device and fastened on 
the main shaft. 
The above and other objects, features and advantages of the present 
invention will become more apparent from the following description when 
taken in conjunction with the accompanying drawings in which a preferred 
embodiment of the present invention is shown.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
As shown in FIGS. 1 through 3, a hydraulically operative clutch type 
transmission 10 includes a casing 11 having an opening 11a, a housing 12 
which is connected to the casing 11 by means of screw members 19 so as to 
cover the opening 11a and so as to accommodate a stator shaft 13 for 
torque converter (not shown) therein, an input shaft 20 which is 
journalled to the stator shaft 13 by means of an antifriction bearing 15 
and which has first and second bores 21 and 22, a main shaft 30 which is 
received within the bore 21 at one end portion 31 thereof and is received 
within the bore 20 to be splined to the input shaft 20 at a spline portion 
32 thereof and which is journalled to a boss portion 11c formed on a side 
wall 11b of the casing 11 by means of an antifriction bearing 16, a 
hydraulically operative clutch device 40 mounted on the main shaft 30, and 
gear members 50 and 60 directly or indirectly meshed with an output gear 
70. 
The main shaft 30 includes a small diameter portion 33, a large diameter 
portion 35, and another small diameter portion 34 which is inserted into 
an inner-race 16a of bearing 16. 
The clutch device 40 is selectively operated by a control arrangement 14 
which is installed on upper portion of the case 11. The clutch device 40 
includes a clutch drum 41 having a sleeve portion 44 which is installed on 
the small diameter portion 33 at an internal portion 43 thereof and which 
is connected to the spline shaft portion 32 at splines 42 thereof, pistons 
45 slidably mounted in a cylinder of the clutch drum 41, a plurality of 
clutch plates 46 mounted in the clutch drum 41 and being movable only in 
an axial direction, a plurality of clutch discs 47 arranged between the 
clutch plates, pressure plates 48 fixed in the clutch drum 41, return 
springs 49 fitted between the pistons 45 and retainers 49d which are 
fastened on the sleeve portion 44 by means of snap rings, respectively. 
The clutch device 40 is energized by pressurized fluid transmitted from the 
control arrangement 14 to the pistons 45 and 45, through means of 
passageways C.sub.1 and C.sub.1 formed in the casing 11, passageways 
C.sub.2 and C.sub.2 formed in a collar member 11d which is inserted into 
the boss portion 11c of the casing 11, passageways C.sub.3 and C.sub.3 
formed in the main shaft 30, grooves 33a and 33a formed in the main shaft 
30, apertures C.sub.4 and C.sub.4 formed in the sleeve portion 44 of the 
clutch drum 41. 
The collar member 11d is prevented from falling out from the boss portion 
11c by a plug 11e which is hermetically secured to the casing by means of 
snap ring and sealingly and rotatably receives the left end portion of the 
main shaft 30. 
Pressurized fluid in passageways C.sub.2 and C.sub.2 leaks out in cavity 
11f defined by the plug 11e, the collar member 11d and the left-side 
surface of the main shaft 30, through means of between the collar member 
11d and the main shaft 30. The fluid stayed in the cavity 11f is led to 
the antifriction bearing 16 through a passageway C.sub.5, and functions as 
lubrication oil. 
The gear members 50 and 60 have clutch hubs 51 and 61 which support a 
plurality of clutch discs 47 which in turn are movable only in the axial 
direction, respectively. 
The gear member 50 is for a forward mode of the transmission and is meshed 
with a counter gear formed on a counter shaft (not shown) which is 
drivingly connected to the output gear 70 through other gear formed on the 
counter shaft (not shown). 
A sliding bearing 53 is securely inserted into an inner periphery 52 of the 
gear member 50 and is rotatably supported on an outer periphery of a race 
member 54 which is splined to the spline shaft portion 32. 
A washer 55 is interposed between the right-side surface of the sleeve 
portion 44 and the left side surfaces of both of the gear member 50 and 
the race member 54, and is splined to the spline shaft portion 32. 
A washer 57 is interposed between the left side surface of the input shaft 
20 and a snap ring 56 which is fastened on the main shaft 30 at the right 
side portion of the race member 54, and is splined to the spline shaft 
portion 32. 
The gear member 60 is for reverse mode of the transmission and is meshed 
with the output gear 70. The gear member 60 is rotatably supported on an 
outer periphery of the large diameter portion 35 through a sliding bearing 
63 which is securely inserted into an inner periphery 62 of the gear 
member 60. 
The diameter of the large diameter portion 35 is larger than that of the 
small diameter portion 33 and also that of another small diameter portion 
34. However, the diameter of the small diameter portion 33 may be larger 
than that of another small diameter portion 34 and vice versa. 
A notch 36 having a plain surface is formed in outer periphery of the end 
portion of the large diameter portion 35 in face of sleeve portion 44 as 
shown in FIG. 2 and FIG. 3. The distance between the plain surface of the 
notch 36 and the center of the main shaft 30 is larger than the radius of 
the small diameter portion 33, but smaller than the radius of the large 
diameter portion 35. The length "l" between the right side shoulder of the 
large diameter portion 35 defining notch 36 and the left side surface of 
the large diameter portion 35 is smaller than the length "s" of the gear 
member 60 as shown in FIG. 2. 
A washer plate 64 is interposed between the right side surface of the gear 
60 and left side surface of the sleeve portion 44, and engages with the 
notch 36 at a flat portion 64b which is formed on inner periphery portion 
64a thereof. The washer plate 64 is mounted on the outer periphery of 
large diameter portion 35 at the inner periphery portion 64a thereof. 
Therefore, the washer plate 64 is fastened on the main shaft 30 in its 
rotating direction, but might be movable in its axial direction. 
It is determined that the sum of thickness "t" of the washer plate 64 and 
length "s" of the gear member 60 is larger than the length "m" of the 
large diameter portion 35. Accordingly, thrust force caused to be 
generated by the operations of the gear member 60 and/or the clutch drum 
41 may not act upon the main shaft 30. 
A thrust plate 65 is interposed between the gear member 60 and the 
inner-race 16a of antifriction bearing 16. 
The lubrication oil is supplied to the relative rotatable slide portions of 
the sliding bearings 53 and 63 from an oil pressure source through means 
of annular passageway P.sub.1 which is defined by the housing 12 and the 
stator shaft 13, passageway P.sub.2 formed in the stator shaft 13, 
passageway P.sub.3 formed in the input shaft 20, passageway P.sub.4 formed 
in the main shaft, branch passageways P.sub.5 and P.sub.6. The lubrication 
oil in passageway P.sub.4 also is supplied to the cavities of the clutch 
device 40 through further branch passageways P.sub.7 and P.sub.7 formed in 
the main shaft 30, passageways P.sub.8 and P.sub.8 formed in the sleeve 
portion 44 of the clutch drum 41. Accordingly, each of slide portions 
between the sliding bearings 53 and 63, outer periphery of the large 
diameter portion 35, race member 54, and the washers 55, 64 and 65 may be 
sufficiently lubricated. 
The antifriction bearing 15 may be lubricated by some of the lubricating 
oil which is leaked from between the passageway P.sub.2 and the passageway 
P.sub.3. It should be noted that the above parts 41, 54, 55, 57 and 64 may 
be prevented from rotating on the main shaft 31 but might be movable in 
their axial direction. 
The operation of the above described hydraulically operative clutch type 
transmission according to the present invention is as follows: 
The clutch plates 46 and the clutch discs 47 of the forward clutch 40F are 
pressed between piston 45 and pressure plate 48 as a result of pressurized 
fluid acting on the piston 45 of the forward clutch 40F of the clutch 
device 40. Therefore, the clutch hub 51 is brought in engagement with the 
clutch drum 41, and then the power transmitted from input shaft 20 to main 
shaft 30 flows to the output gear 70 through means of clutch drum 41, 
clutch plates 46, clutch discs 47, clutch hub 51, gear member 50, and 
counter gears (not shown) to thereby complete the forward mode of the 
transmission. 
When the pressurized fluid acting on the piston 45 of the forward clutch 
40F is discharged, and the pressurized fluid acts on the piston 45 of the 
reverse clutch 40R of the clutch device 40, the clutch hub 61 is brought 
in engagement with the clutch drum 41 in the same manner as that of the 
forward mode of transmission mentioned above. Now, the power is 
transmitted from input shaft 20 to output shaft 70 through means of main 
shaft 30, clutch drum 41, clutch plates 46, clutch discs 47, clutch hub 
61, and gear member 60, to thereby complete the reverse mode of the 
transmission. One of gear members 50 and 60 is maintained under driving 
condition and is being rotated together with main shaft 30, while the 
other of gear members 50 and 60 is maintained under undriving condition 
and is being relatively rotated against main shaft 30. 
The assembly of the hydraulically operative clutch type transmission 
includes the following steps: 
1. Outside of the casing 11, clutch device 40, gear member 50, washers 54 
and 55, snap ring 56, washer 57, gear member 60, washers 64 and 65, and 
antifriction bearing 16 are positioned on the main shaft, respectively, as 
shown in FIG. 1 to have suitable sub-assembly. 
2. Suitable sub-assembly of the parts mentioned above is being inserted 
into the cavity of the casing 11 through the opening 11a from right-hand 
direction in FIG. 1, and then the left end portion 34 of the main shaft 30 
is inserted into the collar member 11d, while outer-race 16 of the 
antifriction bearing 16 is inserted into the boss portion 11c of the 
casing 11. During this step of the assembly, the left end of clutch device 
40 is in contact with the shoulder of washer plate 64 at the sleeve 
portion 44 thereof, while the right end of clutch device 40 is in contact 
with the race member 54 through washer 55 and, therefore, the clutch 
device which is relatively heavy can not move on the main shaft 30. 
3. The stator shaft 13, the input shaft 20, and antifriction bearing 15 are 
independently arranged within the housing 12, and then the spline shaft 
portion 32 is being splined to the bore 22 of the input shaft 20, 
thereafter the housing 12 is being connected to the casing 11 by means of 
the screw members 19.