Shifting valve

A shifting valve for actuation of a multiple position transmission and comprising a shifting element having a plurality of positions for controlling the flow of power fluid to supply power fluid independently for each position of the transmission.

BACKGROUND OF THE INVENTION 
1. Field of the Invention 
This invention relates to improvements in valves and more particularly, but 
not by way of limitation, to a shifting valve for supplying fluid to a 
multiple position transmission for actuation thereof. 
2. Description of the Prior Art 
Most vehicle engines in use today include a transmission having at least 
three positions to provide two forward speeds and one reverse speed for 
the engine. In addition, many engines have transmissions including a 
fourth position in order to provide three forward speeds and one reverse 
speed for the engine. Current trends in engine design suggest a real need 
for efficient and economical transmissions having as many as six positions 
and it will be readily apparent that each additional position for a 
transmission increases the difficulty of providing power fluid to each of 
the positions. 
SUMMARY OF THE PRESENT INVENTION 
The present invention contemplates a novel shifting valve particularly 
designed and constructed for facilitating the operation of a multiple 
position transmission, and comprises a plurality of fluid passageways in 
communication with a fluid source and outlet ports in communication 
independently with each position of the transmission for directing fluid 
to the transmission for operation thereof. A shifting member is interposed 
between the fluid source and the outlet ports and is provided with a 
plurality of lands on the outer periphery thereof for selectively shunting 
the fluid from the fluid source to the outlet ports as required for the 
selective actuation of the multiple positions of the transmission. The 
novel valve is simple and efficient in operation and economical and 
durable in construction.

DESCRIPTION OF THE PREFERRED EMBODIMENT 
Referring to the drawings in detail, reference character 10 generally 
indicates a shifting valve schematically illustrated in FIGS. 1 through 6 
and comprising a suitable valve body (not shown) having a fluid inlet 12 
in communication with a source of pressure fluid (not shown) and a 
discharge port 14 also in communication with the source of pressure fluid 
in order that the fluid may be circulated through the valve body during 
operation of the valve 10 as will be hereinafter set forth. The inlet port 
12 is in communication with a central bore 16 through a passageway array 
comprising three independent passageways 18, 20 and 22 connected by a 
common passageway 24. The passageways 18, 20 and 22 are open to the 
passageway 16 in spaced relation along the length thereof as clearly shown 
in the drawings for directing the fluid into the passageway 16 at 
preselected positions therein. The outlet or discharge port 14 is in 
communication with the passageway 16 through a passageway array comprising 
a first set of spaced passageways 26 and 28 interconnected by a common 
passageway 30 and a second set of spaced passageways 32, 34 and 36 
interconnected by a common passageway 38. The passageway 30 is in 
communication with the discharge port 14 through a passageway 40 and 42, 
and the passageway 38 is in communication with the discharge port 14 
through a passageway 44 and the passageway 42. 
Assuming that the valve 10 is to be utilized in combination with a 
transmission (not shown) having six positions, with three clutches (not 
shown) being provided for achieving said six positions, the valve body 
(not shown) is provided with a first actuator outlet 46 in operable 
communication with one of the clutch members (not shown), a second 
actuator outlet 48 in operable communication with the second clutch member 
(not shown), and a third actuator outlet 50 in operable communication with 
the third clutch member (not shown). The outlet 50 is in direct 
communication with the passageway 16 through a passageway 52 and through a 
branch passageway 54 which extends into communication with a passageway 
56. The passageway 54 is also in communication with the passageway 16 
through a check valve 58 interposed between the passageway 54 and a 
passageway 60. The outlet 46 is in direct communication with the 
passageway 16 through a passageway 62 and an offset branch passageway 64. 
The passageway 62 is also in communication with the passageway 16 through 
a branch passageway 66 having a pair of spaced passageways 68 and 70 
extending into communication with the passageway 16. The outlet 48 is in 
direct communication with the passageway 16 through a passageway 72 and 
also in communication with the passageway 60 through a branch passageway 
74. It will thus be readily apparent that the outlets 46, 48 and 50 are 
all in communication with the passageway 16 through a plurality of 
passageways open to the passageway 16 in spaced relationship along the 
length thereof. 
A slide member of shifting element 76 is slidably disposed within the 
passageway 16 and may be reciprocated therein in any suitable manner (not 
shown) as is well known for selective distribution of the pressure fluid 
to the outlets 46, 48 and 50. The shifting element 76 is provided with a 
first land member 78 on the outer end thereof suitably inscribed with an 
index or arrow 80 for selective register with preselected positions in the 
bore or passageway 16 as indicated by the numerals 1 through 6 in the 
drawings, and as will be hereinafter set forth. A second land 82 is 
provided on the slide member 76 spaced from the land 78 by an annular 
groove or recess 84. A third land 86 is spaced from the land 82 by a 
groove or annular recess 88. A fourth land 90 is spaced from the land 86 
by an annular groove 92, and a fifth land 94 is spaced from the land 90 by 
an annular recess or groove 96. 
In a first position for the slide member 76 wherein the index 80 is in 
substantial alignment with the first indicated position as shown in FIG. 
1, the recess 84 is disposed in communication with the passageways 44 and 
60, and the passageways 36, 56, 18 and 52 are closed or blocked off by the 
land 82. The recess 88 is open to the passageways 62 and 64, and the 
passageways 20, 22, 72 and 68 are closed or blocked off by the land 86. 
The recess 92 is open to the passageway 26 and the recess 96 is in 
communication with the passageways 28 and 70. The lands 78 and 94 close 
the opposite ends of the passageway 16 from all the other passageways. In 
this position of the slide member 76, the incoming pressure fluid at the 
inlet 12 is blocked or sealed from the outlets 46, 48 and 50 and there 
will be no pressure fluid supplied to the transmission (not shown), and 
any pressure present at the port 46 is vented through 66, 70 and 40, and 
pressure at ports 48 and 50 is vented to the outlet 14 through lines 60, 
44 and 42, thus providing a first drive position for the transmission. 
When the slide element 76 is shifted to a second position, as shown in FIG. 
2, the recess 88 is incommunication with the passageways 20 and 62 whereby 
the pressure fluid is directed from the inlet 12 to the outlet 46, and 
thus to the gear train (not shown) for applying pressure thereto in one 
direction to provide a second drive position for the transmission. At the 
same time, the inlet 12 is closed from the outlets 48 and 50 by the lands 
86 and 82, respectively, thus precluding application of pressure fluid 
through the outlets 48 and 50. The outlets 48 and 50 are in communication 
with the pressure fluid outlet 14 through the passageways 60, 44 and 42 
since the recess 84 is in communication with passageways 56, 60, 36, 34 
and 44. The passageway 54 is in communication with the passageway 60 
through the check valve 58 which permits the flow of fluid from the 
passageway 54 into the passageway 60, but precludes the back flow of 
pressure from the passageway 60 to the passageway 54. In this manner, the 
outlets 50 and 48 remain vented through the outlet 14 to the pressure 
fluid supply (not shown). The outlet 46 is closed from outlet 14 by the 
lands 86 and 90, thus assuring that the pressure fluid will be retained at 
the outlet 46 during activation of the transmission in this selected 
position. 
When the slide member 76 is moved to a third position as shown in FIG. 3, 
the land member 82 precludes communication between the pressure inlet 12 
and the outlets 46 and 50. Recess 88, however, provides communication 
between the pressure inlet 12 and the outlet 48. In this position of the 
slide member 76, pressure fluid is directed to the gear train (not shown) 
of the outlet 48 for providing a third operating position for the 
transmission (not shown). At the same time, the port 50 is in 
communication with the pressure fluid return outlet 14 through the 
passageways 56, 34, 36, 44 and 42 for relieving any fluid pressure present 
at the port 50. In addition, the port 46 is in communication with the 
outlet 14 through the passageways 66, 70, 40 and 42. Communication between 
the port 48 and the outlet 14 is precluded by the lands 78 and 86, thus 
assuring that the pressure fluid will be maintained at the port 48 as long 
as the slide element 76 is in the position shown in FIG. 3. 
When the slide member 76 is in the position shown in FIG. 4, still another 
driving position is provided for the transmission (not shown). In this 
position of the element 76, communication is established between the inlet 
12 and the outlet 48 through the recess 88 and passageways 22 and 72, and 
simultaneously with the port 46 through the passageways 68, 66 and 62. In 
this manner, pressure fluid is simultaneously provided for the gear trains 
(not shown) of the clutches (not shown) associated with both the ports 46 
and 48 to provide a fourth drive position for the transmission (not 
shown). Pressure is relieved from the port 50 through the passageways 52, 
54, 56, 36, 38, 44 and 42 in the same manner as in the position shown in 
FIG. 3. 
When the shifting element 76 is in the position shown in FIG. 5, the 
pressure fluid inlet 12 is in communication with the outlet 50 through the 
groove 84 which establishes communication between the passageways 18 and 
52. Thus, fluid pressure is directed to the gear train (not shown) of the 
clutch (not shown) associated with the port 50 for providing another 
actuation position for the transmission (not shown). Communication between 
the port 50 and the return outlet 14 is precluded by the lands 78 and 82, 
thus assuring that the pressure fluid will be held at the port 50. At the 
same time, the port 48 is closed from communication with the outlet 14 by 
the lands 78 and 82, and the port 46 is vented through lines 66, 68, 26, 
30, 40 and 42. Thus pressure fluid is maintained at each of the outlets 48 
and 50 for providing still another stage of actuation or drive position 
for the transmission (not shown). 
As the shifting element 76 is moved to the position shown in FIG. 6, 
communication remains established between the pressure fluid inlet 12 and 
the outlet 48 through 58 and 60 around the recess 84, and communication is 
also established between the inlet 12 and outlet 46. Thus, still another 
actuation position is provided for the transmission (not shown). 
From the foregoing it will be apparent that a plurality of driving or 
actuation positions for a transmission may be easily selected by the 
reciprocation of the shifting element 76. Of course, suitable means, such 
as mechanical stops and the like (not shown) may be provided for 
cooperation with the shifting element 76 in order to facilitate a positive 
determination of the plurality of positions therefor with respect to the 
ports and passageways provided in the shifting valve. 
Whereas the present invention has been described in particular relation to 
the drawings attached hereto, it should be understood that other and 
further modifications, apart from those shown or suggested herein may be 
made within the spirit and scope of this invention.