CA2012430A1 - Linkage for controlling transmission pressure reduction valve - Google Patents
Linkage for controlling transmission pressure reduction valveInfo
- Publication number
- CA2012430A1 CA2012430A1 CA 2012430 CA2012430A CA2012430A1 CA 2012430 A1 CA2012430 A1 CA 2012430A1 CA 2012430 CA2012430 CA 2012430 CA 2012430 A CA2012430 A CA 2012430A CA 2012430 A1 CA2012430 A1 CA 2012430A1
- Authority
- CA
- Canada
- Prior art keywords
- lever
- slot means
- link
- bracket
- plunger
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Abandoned
Links
Landscapes
- Control Of Transmission Device (AREA)
- Transmission Devices (AREA)
Abstract
LINKAGE FOR CONTROLLING TRANSMISSION
PRESSURE REDUCTION VALVE
Abstract of the Disclosure A control for automatic transmission pressure valves having a slotted lever rotatably mounted to a slotted stationary bracket and interconnected by a link passing through both slots. The link transmits an actuating force which rotatably displaces the lever and produces the resultant displacement of the valve. The intersection of the two slots at the location of the link produces a lever and consequent valve displacement which can be varied nonlinearly with respect to the displacement of the link.
PRESSURE REDUCTION VALVE
Abstract of the Disclosure A control for automatic transmission pressure valves having a slotted lever rotatably mounted to a slotted stationary bracket and interconnected by a link passing through both slots. The link transmits an actuating force which rotatably displaces the lever and produces the resultant displacement of the valve. The intersection of the two slots at the location of the link produces a lever and consequent valve displacement which can be varied nonlinearly with respect to the displacement of the link.
Description
æ43c~
G-3979 C-41~4 LINKAG~ FOR CON~ROLLING TRANSMI~SION
PRESSURE RED~CTION VAL,VE
_ckground of the Invention This invention is related to linkages used to control the position of pressure reducing valves~ and more particularly, to linkages used to control valves as a function of throttle position in automatic transmissions.
The present invention will find particular use as a control for automatic transmission valves employing transfer functions between throttle travel and valve plunger travel. The transfer functions can be optimized to provide the most suitable transmission clutch apply pressures to compensate for the torque developed by the engine and other system variables.
Prior art methods of controlling the position of automatic transmission valves use either levers or cams to provide the desired displacement of the valves.
The relationship between the throttle position and the valve displacementl or the transfer function, must provide an appropriate level of pressure to apply the friction clutches in the transmission. The system is optimized to provide a suitable compromise between the conflicting goals of long clutch life with minimal clutch slippage (high pressure applications of the clutches) and of smooth shifts which permit some clutch slippage (low pressure applications of the clutches).
A compromise is possible because each goal dominates a particular set of conditions. The desirability of smooth shifts dominates at low vehicle speeds and low levels of throttle. The desirability of :: , , - ' ~, .
hard shifts (rapid, high pressure shifts) increases with an increase in available torque which is produced by an increase in throttle displacement. The desirability of hard shifts also increases with the effective amount of vehicle inertia seen by the clutches. The position of the automatic transmission pressure reducing valve controls the magnitude of the oil pressure used to apply the friction clutches. The optimal transfer function is largely dependent on the en~ine torque as a function of throttle displacement and on the mass of the vehicle. The mass is constant, but the engine torque changes as a function of throttle position.
Sometimes an appropriate relationship to accommodate the needs of the system can be provided by a constant linear relationship between the throttle position and the valve position. When this is the case, either a cam or a lever can be used to provide the desired means of positioning the valve. Where a nonlinear function is more suitable, cams have been used exclusively to provide the desired transfer function. Prior art levers used to position pressure reducing valves have been unable to accommodate this requirement because they only provide a nearly constant relationship between the throttle displacement and the valve displacement.
Cams and levers are alternate means of translating an a~ial displacement into a rotational displacement. Prior to this, cams have been used because they have provided the capability of tuning the transfer function to the demands of the system.
3 z~Z4~
Summary of the Invention The present invention has the advantage over prior art lever syste~s used for controlling the position of automatic transmission pressure reducing S valves by providing a wide variety of transfer functions between the throttle position and the valve. The potential advantage of this system over a cam system is that, in some circumstances, it will be better suited to certain packaging constraints within certain transmissions than a cam system.
It is an object of this invention to provide an improved throttle linkage~ wherein a slotted lever is pivotally mounted on a slotted bracket, with a link interconnecting the slots.
It is another an object of this invention to provide an improved throttle linkage, wherein ~he intersection of the slots of a slotted bracket and a slotted lever through which a link passes produces the desired transfer function between the input of the throttle position and the output of the valve position as the link travels in the slots.
~ hese and other objects and advantages will be more apparent from the following description and drawings.
Description of the Drawin~
FIG. 1 is a view perpendicular to the axis o~
a valve plunger showing the valve plunger, a bracket and a lever with their slots clearly visible and overlapping in the closed throttle position, a link, and schematic representations of the throttle pedal, , ' , .' -' ~ `' ' ':'' ' .' ~ :
3~
the throttle assembly, and the intervening mechanisms between the pedal, the throttle and the valve linkage;
FIG. 2 is an enlarged portion of Fig. 1 showing the bracket, lever, link, and plunger at wide-open-throttle position;
FIG. 3 shows a view in the direction of line 3--3 of FIG. 1; and FIG. 4 is a graph showing throttle valve plunger travel as a function of link travel.
Description of the Preferred Embodiment The accompanying drawings illustrate a representative form of a control for automatic transmission valves based on levers which are capable of providing a wide variety of transfer functionsl bo~h linear and nonlinear. A valve plunger 10 is shown in the illustrations. The plunger 10 travels axially in and out of the transmission valve body 12 and is functionally connected to a pressure reducing valve not illustrated. The pressure reducing valve may be constructed in accordance with United States Patent 3,893,472 issued to Schuster July 8, 1975l and assigned to the assignee of this application.
A bracket 14 is attached to a transmission 25 case 16. In FIG. 3, three machine screws 18 are shown holding the bracket 14 to the transmission case 16.
This is not the exclusive means of attaching the bracket 14 to the transmission case 16. Any means of providing an attachment between the two parts with adequate strength i5 considered appropriate.
A lever 20 is supported on the bracket 14~for rotation about an axis 19 by a pin 22. The pin 22 is ~ .
: ' z*~
press fit to the bracket 14 and the lever 20 is rotatably supported thereon~ In the alternative, the pin 22 can be secured to the lever 20 and rotatably supported in the bracket 14.
The lever 20 and the bracket 14 have slots 21 and 15, respectively. A link 24 operatively connects the bracket 14 with the lever 20. The link 24 also connects a throttle displacement transmitting mechanism 26 to the lever 20. A link end 23 passes through both the slot 21 in the lever 20, and the slot 15 in the bracket 14. The link end 23 is shown as having two rollers 28 and 30 on it to reduce friction between the link 24 and the lever 20, and the link 24 and the bracket 14. ~ thrust washer 32 helps retain the lever roller 28 on the inboard side, a crimped throttle linkage washer 34 retains the bracket roller 30 from the outboard side and prevents the link 24 from slipping out of the lever 20. The link 24 forces the lever 20 to follow a transfer function 36, shown in FIG. 4, provided by the slot 15 in the bracket 14. The opposite end 25 of the link 24 is attached to a mechanism 26 which is attached to a throttle mechanism 38. The throttle mechanism 38 is, in turn, attached through an actuating mechanism 40 to the throttle pedal 42.
The throttle pedal 42 is undisplaced in the closed throttle position. Closed throttle corresponds to engine idle. The lever 20 does not contact the valve plunger 10 with the throttle pedal 42 in this position.
When the pedal 4~ is displaced by a driver's foot from the closed throttle position~ the actuating ,.. , . . ~ . .
. ~ . , .
' ' '- ~ ' . . .
.
z~Z~L3~
mechanism 40 connecting it to the throttle mechanism 38 displaces (opens) the throttle. In turn, the throttle displacement transmitting mechanism 26 connecting the throttle mechanism 38 to the link 24 displaces the link axially when the throttle mechanism 38 is displaced.
~ s the link 24 is displaced by the motion of the throttle pedal 42, the link end 23 translates along the bracket slot 15 and the lever slot 21. This link end 23 moves in the lever slot 21 because the bracket 1~ slot 15 is not a constant distance from the center of rotation 19. The distance of the link end 23 of this link 24 from the center of rotation 19 controls the amount of travel of lever 20 relative to the amount of travel of link 24. This amount of travel of the lever 20 is proportional to the distance of the link end 23 from the center of rotation 19 of the lever 20.
The lever 20 produces the desired displacement of the valve plunger 10 when it abuts the contact surface of the valve plunger 44, and rotates about the center of rotation 19 in response to the displacement of the link 24.
The valve plunger 10, in turn, displaces the pressure reducing valve~ The displacement of the valve alters the pressure of the oil being used to control pressure and shifting in the transmission in a manner well-known.
Obviously, many modifications and variations of the present invention are possible in light of the above teaching. It is therefore to be understood, that within the scope of the appended claims, the invention may be practiced otherwise than as specifically described.
; .
.
G-3979 C-41~4 LINKAG~ FOR CON~ROLLING TRANSMI~SION
PRESSURE RED~CTION VAL,VE
_ckground of the Invention This invention is related to linkages used to control the position of pressure reducing valves~ and more particularly, to linkages used to control valves as a function of throttle position in automatic transmissions.
The present invention will find particular use as a control for automatic transmission valves employing transfer functions between throttle travel and valve plunger travel. The transfer functions can be optimized to provide the most suitable transmission clutch apply pressures to compensate for the torque developed by the engine and other system variables.
Prior art methods of controlling the position of automatic transmission valves use either levers or cams to provide the desired displacement of the valves.
The relationship between the throttle position and the valve displacementl or the transfer function, must provide an appropriate level of pressure to apply the friction clutches in the transmission. The system is optimized to provide a suitable compromise between the conflicting goals of long clutch life with minimal clutch slippage (high pressure applications of the clutches) and of smooth shifts which permit some clutch slippage (low pressure applications of the clutches).
A compromise is possible because each goal dominates a particular set of conditions. The desirability of smooth shifts dominates at low vehicle speeds and low levels of throttle. The desirability of :: , , - ' ~, .
hard shifts (rapid, high pressure shifts) increases with an increase in available torque which is produced by an increase in throttle displacement. The desirability of hard shifts also increases with the effective amount of vehicle inertia seen by the clutches. The position of the automatic transmission pressure reducing valve controls the magnitude of the oil pressure used to apply the friction clutches. The optimal transfer function is largely dependent on the en~ine torque as a function of throttle displacement and on the mass of the vehicle. The mass is constant, but the engine torque changes as a function of throttle position.
Sometimes an appropriate relationship to accommodate the needs of the system can be provided by a constant linear relationship between the throttle position and the valve position. When this is the case, either a cam or a lever can be used to provide the desired means of positioning the valve. Where a nonlinear function is more suitable, cams have been used exclusively to provide the desired transfer function. Prior art levers used to position pressure reducing valves have been unable to accommodate this requirement because they only provide a nearly constant relationship between the throttle displacement and the valve displacement.
Cams and levers are alternate means of translating an a~ial displacement into a rotational displacement. Prior to this, cams have been used because they have provided the capability of tuning the transfer function to the demands of the system.
3 z~Z4~
Summary of the Invention The present invention has the advantage over prior art lever syste~s used for controlling the position of automatic transmission pressure reducing S valves by providing a wide variety of transfer functions between the throttle position and the valve. The potential advantage of this system over a cam system is that, in some circumstances, it will be better suited to certain packaging constraints within certain transmissions than a cam system.
It is an object of this invention to provide an improved throttle linkage~ wherein a slotted lever is pivotally mounted on a slotted bracket, with a link interconnecting the slots.
It is another an object of this invention to provide an improved throttle linkage, wherein ~he intersection of the slots of a slotted bracket and a slotted lever through which a link passes produces the desired transfer function between the input of the throttle position and the output of the valve position as the link travels in the slots.
~ hese and other objects and advantages will be more apparent from the following description and drawings.
Description of the Drawin~
FIG. 1 is a view perpendicular to the axis o~
a valve plunger showing the valve plunger, a bracket and a lever with their slots clearly visible and overlapping in the closed throttle position, a link, and schematic representations of the throttle pedal, , ' , .' -' ~ `' ' ':'' ' .' ~ :
3~
the throttle assembly, and the intervening mechanisms between the pedal, the throttle and the valve linkage;
FIG. 2 is an enlarged portion of Fig. 1 showing the bracket, lever, link, and plunger at wide-open-throttle position;
FIG. 3 shows a view in the direction of line 3--3 of FIG. 1; and FIG. 4 is a graph showing throttle valve plunger travel as a function of link travel.
Description of the Preferred Embodiment The accompanying drawings illustrate a representative form of a control for automatic transmission valves based on levers which are capable of providing a wide variety of transfer functionsl bo~h linear and nonlinear. A valve plunger 10 is shown in the illustrations. The plunger 10 travels axially in and out of the transmission valve body 12 and is functionally connected to a pressure reducing valve not illustrated. The pressure reducing valve may be constructed in accordance with United States Patent 3,893,472 issued to Schuster July 8, 1975l and assigned to the assignee of this application.
A bracket 14 is attached to a transmission 25 case 16. In FIG. 3, three machine screws 18 are shown holding the bracket 14 to the transmission case 16.
This is not the exclusive means of attaching the bracket 14 to the transmission case 16. Any means of providing an attachment between the two parts with adequate strength i5 considered appropriate.
A lever 20 is supported on the bracket 14~for rotation about an axis 19 by a pin 22. The pin 22 is ~ .
: ' z*~
press fit to the bracket 14 and the lever 20 is rotatably supported thereon~ In the alternative, the pin 22 can be secured to the lever 20 and rotatably supported in the bracket 14.
The lever 20 and the bracket 14 have slots 21 and 15, respectively. A link 24 operatively connects the bracket 14 with the lever 20. The link 24 also connects a throttle displacement transmitting mechanism 26 to the lever 20. A link end 23 passes through both the slot 21 in the lever 20, and the slot 15 in the bracket 14. The link end 23 is shown as having two rollers 28 and 30 on it to reduce friction between the link 24 and the lever 20, and the link 24 and the bracket 14. ~ thrust washer 32 helps retain the lever roller 28 on the inboard side, a crimped throttle linkage washer 34 retains the bracket roller 30 from the outboard side and prevents the link 24 from slipping out of the lever 20. The link 24 forces the lever 20 to follow a transfer function 36, shown in FIG. 4, provided by the slot 15 in the bracket 14. The opposite end 25 of the link 24 is attached to a mechanism 26 which is attached to a throttle mechanism 38. The throttle mechanism 38 is, in turn, attached through an actuating mechanism 40 to the throttle pedal 42.
The throttle pedal 42 is undisplaced in the closed throttle position. Closed throttle corresponds to engine idle. The lever 20 does not contact the valve plunger 10 with the throttle pedal 42 in this position.
When the pedal 4~ is displaced by a driver's foot from the closed throttle position~ the actuating ,.. , . . ~ . .
. ~ . , .
' ' '- ~ ' . . .
.
z~Z~L3~
mechanism 40 connecting it to the throttle mechanism 38 displaces (opens) the throttle. In turn, the throttle displacement transmitting mechanism 26 connecting the throttle mechanism 38 to the link 24 displaces the link axially when the throttle mechanism 38 is displaced.
~ s the link 24 is displaced by the motion of the throttle pedal 42, the link end 23 translates along the bracket slot 15 and the lever slot 21. This link end 23 moves in the lever slot 21 because the bracket 1~ slot 15 is not a constant distance from the center of rotation 19. The distance of the link end 23 of this link 24 from the center of rotation 19 controls the amount of travel of lever 20 relative to the amount of travel of link 24. This amount of travel of the lever 20 is proportional to the distance of the link end 23 from the center of rotation 19 of the lever 20.
The lever 20 produces the desired displacement of the valve plunger 10 when it abuts the contact surface of the valve plunger 44, and rotates about the center of rotation 19 in response to the displacement of the link 24.
The valve plunger 10, in turn, displaces the pressure reducing valve~ The displacement of the valve alters the pressure of the oil being used to control pressure and shifting in the transmission in a manner well-known.
Obviously, many modifications and variations of the present invention are possible in light of the above teaching. It is therefore to be understood, that within the scope of the appended claims, the invention may be practiced otherwise than as specifically described.
; .
.
Claims (3)
1. A control mechanism functionally connected between an operator controlled engine throttle mechanism and an automatic transmission pressure regulator valve having a plunger, comprising:
lever means for providing a lever ratio including arm means, first arm means having a slot means for changing the lever ratio and second arm means having a contact surface means for displacing the plunger;
bracket means fixed relative to the transmission including means for pivotally mounting the lever and having cam slot means overlapping said slot means; and link means substantially axially movable for providing input movement including a first end operatively connected to the throttle mechanism, and a second end passing through the intersection of said cam slot means in said bracket and said slot means in said lever, and cooperating therewith for translating the axial motion of the link means into a predetermined rotary pattern established by the cam slot, said plunger being disposed in abutment with the contact surface of the lever for axial displacement thereby to provide a predetermined pressure.
lever means for providing a lever ratio including arm means, first arm means having a slot means for changing the lever ratio and second arm means having a contact surface means for displacing the plunger;
bracket means fixed relative to the transmission including means for pivotally mounting the lever and having cam slot means overlapping said slot means; and link means substantially axially movable for providing input movement including a first end operatively connected to the throttle mechanism, and a second end passing through the intersection of said cam slot means in said bracket and said slot means in said lever, and cooperating therewith for translating the axial motion of the link means into a predetermined rotary pattern established by the cam slot, said plunger being disposed in abutment with the contact surface of the lever for axial displacement thereby to provide a predetermined pressure.
2. A control mechanism functionally connected between an operator controlled engine throttle mechanism and an automatic transmission pressure regulator valve plunger, comprising:
a lever with two arms, the first arm having a slot means for changing the lever ratio, and the second arm having a contact surface means for displacing the plunger;
a bracket fixed relative to the transmission with means for pivotally mounting the lever and having cam slot means for providing a pattern for controlling said lever ratio overlapping said slot means; and link means having first and second ends, the first end operatively connected to the throttle, and the second end passing through the intersection of the cam slot means in the bracket and the slot means in the lever for translating the axial motion of the link into the rotary motion of the lever in a predetermined pattern established by said slot means and said cam slot means.
a lever with two arms, the first arm having a slot means for changing the lever ratio, and the second arm having a contact surface means for displacing the plunger;
a bracket fixed relative to the transmission with means for pivotally mounting the lever and having cam slot means for providing a pattern for controlling said lever ratio overlapping said slot means; and link means having first and second ends, the first end operatively connected to the throttle, and the second end passing through the intersection of the cam slot means in the bracket and the slot means in the lever for translating the axial motion of the link into the rotary motion of the lever in a predetermined pattern established by said slot means and said cam slot means.
3. A control mechanism functionally connected between an operator controlled engine throttle mechanism and an automatic transmission pressure regulator valve plunger, comprising:
a lever with two arms, the first arm having slot means with its axis passing through the center of rotation of the lever for effecting a lever ratio change, and the second arm having contact surface means for displacing the plunger;
a bracket disposed on the transmission including means for pivotally mounting the lever and cam slot means for providing a pattern for controlling said lever ratio change and overlapping said slot means; and link means having first and second ends, the first end operatively connected to the throttle, and the second end passing through the intersection of the cam slot means in the bracket and the slot means in the lever for translating the axial motion of the link into the rotary motion of the lever in a predetermined pattern established by said slot means and said cam slot means.
a lever with two arms, the first arm having slot means with its axis passing through the center of rotation of the lever for effecting a lever ratio change, and the second arm having contact surface means for displacing the plunger;
a bracket disposed on the transmission including means for pivotally mounting the lever and cam slot means for providing a pattern for controlling said lever ratio change and overlapping said slot means; and link means having first and second ends, the first end operatively connected to the throttle, and the second end passing through the intersection of the cam slot means in the bracket and the slot means in the lever for translating the axial motion of the link into the rotary motion of the lever in a predetermined pattern established by said slot means and said cam slot means.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US39191889A | 1989-07-27 | 1989-07-27 | |
| US07/391,918 | 1989-07-27 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA2012430A1 true CA2012430A1 (en) | 1991-01-27 |
Family
ID=23548517
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA 2012430 Abandoned CA2012430A1 (en) | 1989-07-27 | 1990-03-16 | Linkage for controlling transmission pressure reduction valve |
Country Status (2)
| Country | Link |
|---|---|
| JP (1) | JPH0369848A (en) |
| CA (1) | CA2012430A1 (en) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP4742954B2 (en) | 2006-03-31 | 2011-08-10 | オムロン株式会社 | Electromagnetic relay |
-
1990
- 1990-03-16 CA CA 2012430 patent/CA2012430A1/en not_active Abandoned
- 1990-07-26 JP JP19895490A patent/JPH0369848A/en active Pending
Also Published As
| Publication number | Publication date |
|---|---|
| JPH0369848A (en) | 1991-03-26 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| EEER | Examination request | ||
| FZDE | Dead |