Title of Invention

"SYSTEM FOR DIAGNOSING A FAILURE OF AN OUTPUT-SHAFT SPEED SENSOR OF AN AUTOMATIC TRANSMISSION FOR A VEHICLE."

Abstract

A system for diagnosing a failure of an output-shaft speed sensor of an automatic transmission is provided, which comprises an inhibitor switch, an input-shaft speed sensor detecting, an output-shaft speed sensor, an engine speed sensor, and a control unit. The control unit being programmed to execute a diagnostic control comprising: determining whether a current shift range is a forward driving range; determining whether a predetermined failure determination condition exists based on a current shift speed, an input-shaft speed, an output-shaft speed, and an engine speed, if the current shift range is the forward driving range; and maintaining the current shift speed if a predetermined down-shift condition exists, or up-shifting a shift speed if a predetermined up-shift condition exists, if the predetermined failure determination condition exists.

Full Text

SYSTEM FOR DIAGNOSING A FAILURE OF AN OUTPUT-SHAFT SPEED SENSOR OF AN AUTOMATIC TRANSMISSION FOR A VEHICLE FIELD OF THE INVENTION The present invention relates to a system for diagnosing a failure of an output-shaft speed sensor of an automatic transmission for a vehicle. BACKGROUND OF THE INVENTION Generally, an automatic transmission for a vehicle comprises a transmission control unit (TCU) which automatically regulates a gear ratio, according to various driving conditions such as vehicle speed and engine load. The transmission control unit regulates an output-shaft speed of a planetary gear set by controlling operation of the clutches and brakes mounted to gear trains. To regulate the otitput-shaft speed, the transmission control unit receives signals representative of vehicle driving parameters, and determines a solenoid valve duty control signal according to a predetermined program. The solenoid valve regulates hydraulic pressure supplied to clutches and brakes that are mounted to gear trains, and it is operated according to the solenoid valve duty control signal. The transmission control unit judges whether the output-shaft speed sensor has failed or not based on the detected output-shaft speed signal received from the output-shaft speed sensor. For example, in prior art, the transmission control unit judges the output-shaft speed sensor to have failed if a difference between the output-shaft speed signal of the output-shaft speed sensor and the vehicle speed signal of a vehicle speed sensor is above 30% of the output-shaft speed signal. If the output-shaft speed sensor has failed, the transmission control unit controls to not shift a shift range to a target shift ratio, and controls to hold the shift ratio in a second speed or a third speed, and controls to display an engine inspection lamp for a driver in order to seek maintenance for the failed part. However, with above the prior art, it is impossible to diagnose the output-shaft speed sensor when the engine speed sensor is removed. Furthermore, it is possible to misjudge a failure of the output-shaft speed sensor when the engine speed sensor has interference. SUMMARY OF THE INVENTION In a preferred embodiment of the present invention, the system for diagnosing a failure of the output-shaft speed sensor comprises: an inhibitor switch, an input-shaft speed sensor, an output-shaft speed sensor, an engine speed sensor, and a control unit. The inhibitor switch detects a shift range; the input-shaft speed sensor detects a turbine speed and generates a corresponding signal; the output-shaft speed sensor detects an output-shaft speed of the automatic transmission and generates a corresponding signal; the engine speed sensor detects an engine speed and generates a corresponding signal; and the control unit diagnoses a failure of the output-shaft speed sensor on the basis of signals of the inhibitor switch, the input-shaft speed sensor, the output-shaft speed sensor, and the engine speed sensor, the control unit being programmed to execute a diagnostic control comprising: determining whether a current shift range is a forward driving range; determining whether a predetermined failure determination condition exists based on a current shift speed, an input-shaft speed, an output-shaft speed, and an engine speed, if the current shift range is the forward driving range; and maintaining the current shift speed if a predetermined down-shift condition exists, or up-shifting a shift speed if a predetermined up-shift condition exists, if the predetermined failure determination condition exists. BRIEF DESCRIPTION OF THE DRAWINGS The accompanying drawings, which are incorporated in and constitute a part of the specification, illustrate an embodiment of the invention, and, together with the description, serve to explain the principles of the invention, where: FIG. 1 is a flow chart showing a failure-diagnosis method of an output-shaft speed sensor of an automatic transmission for a vehicle according to a preferred embodiment of the present invention; FIG. 2 is a flow chart showing a shift restriction method according to the preferred embodiment of the present invention; FIG. 3 is a flow chart showing the process of a failure diagnosis process of the method according to the preferred embodiment of the present invention; and FIG. 4 is a block diagram of a failure-diagnosis system of an output-shaft speed sensor of an automatic transmission for a vehicle according to a preferred embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a preferred embodiment of the present invention will be described in detail with reference to the accompanying drawings. As shown in FIG. 4, a system for diagnosing a failure of an output-shaft speed sensor of an automatic transmission for a vehicle according to the preferred embodiment of the present invention comprises an inhibitor switch 10, an input-shaft speed sensor (PG-A sensor) 20, an output-shaft speed sensor (PG-B sensor) 30, an engine speed sensor 40, and a transmission control unit (TCU) 50. The inhibitor switch 10 is a device for detecting a position of a shift lever and outputting a corresponding electrical signal. The input-shaft speed sensor 20 is a sensor which detects a speed of a turbine shaft of a torque converter 80, and outputs a predetermined signal. The turbine shaft is connected to the input-shaft of an automatic transmission 90. The output-shaft speed sensor 30 detects an output-shaft speed of the automatic transmission, and outputs a corresponding electrical signal. The engine speed sensor 40 is an engine speed sensing portion which detects the speed of a crankshaft of an engine 70, which varies according to an engine operation state, and outputs a corresponding electrical signal. The transmission control unit 50 receives the signals output from the above switch and sensors, and determines a failure state of the output-shaft speed sensor 30. If the output-shaft speed sensor 30 has failed, the transmission control unit 50 outputs a failure signal and a shift control signal to a hydraulic pressure control element 60 which controls hydraulic pressure of the automatic transmission in order to realize a specific shift speed. The transmission control unit 50 preferably includes a processor, a memory, and other necessary hardware and software components as will be understood by persons skilled in the art, to permit the control unit to communicate with sensors and execute the diagnosing method as described herein. With the above structure, a preferred embodiment of the present invention diagnoses a failure of an output-shaft speed sensor of an automatic transmission and controls a shift operation corresponding to the process, as shown in Figs.1 to 3. Firstly, with reference to Fig. 1, the transmission control unit 50 determines if a current shift range is a forward driving range in step S110. If it is determined that the current shift range is a forward driving range in step S110, the transmission control unit 50 receives signals from the input-shaft speed sensor 20, the output-shaft speed sensor 30, and the engine speed sensor 40, and performs a diagnosis of the output-shaft speed sensor 30 according to the current shift range in steps S112 and S114. If it is determined that the output-shaft speed sensor has failed in step S114, the transmission control unit 50 performs a predetermined shift control as described in steps S114 to S120. That is, if a predetermined down-shift condition exists, the transmission control unit 50 controls to maintain a current shift speed without down-shifting (S116), and if a predetermined up-shift condition exists, the transmission control unit 50 controls to up-shift the transmission into one speed higher than a current shift speed (S118 and S120). The predetermined down-shift condition may be determined as a general down-shift condition of an automatic transmission shift control. The predetermined up-shift condition includes: (1) an engine speed Ne is higher than a predetermined engine speed (for example, 5800 rpm) and an angular acceleration of an engine is greater than 0 (that is, dNe/dt > 0), or (2) a turbine speed Nt is higher than a predetermined turbine speed (for example, 5800 rpm) and an angular acceleration of a turbine shaft is greater than 0 (that is, dNt/dt > 0). If at least one of (1) and (2) exists, it is determined that the predetermined up-shift condition exists. The diagnosis method according to the preferred embodiment of the present invention may further comprise the shift restriction method of FIG. 2, which is simultaneously performed with the diagnosis of FIGs. 1 and 3. Initially, as shown in FIG. 2, the transmission control unit 50 determines whether a predetermined shift restriction condition exists in step S212. The predetermined shift restriction condition comprises: (1) A turbine speed Nt is higher than a predetermined turbine speed (for example, 500 rpm), and (2) An angular acceleration of the output-shaft is less than a predetermined angular acceleration (for example, -19rev/sec^2). While a vehicle is decelerated, the deceleration of the vehicle has a physical limit, and therefore the angular acceleration of the output-shaft of the automatic transmission has also a limit. The predetermined angular acceleration is determined as the physical limit of the angular acceleration of an output-shaft. If the angular acceleration of the output-shaft is less than the predetermined angular acceleration when the turbine speed is higher than the predetermined turbine speed, it is determined that the output-shaft speed sensor has failed. The predetermined shift restriction condition may further comprise that a current shift mode is neither an extremely low temperature mode nor a fail-safe mode. The extremely low temperature mode is a shift mode wherein a shift speed is held at a specific shift speed (for example, a second shift speed) if the temperature is lower than a predetermined temperature (for example, -29 degrees Celsius), and the fail-safe mode is a shift mode wherein a shift speed is held at a specific shift speed (for example, a third shift speed). Because the shift speed is held at specific shift speeds in the extremely low temperature mode or the fail-safe mode, it is not needed to perform a shift restriction under these conditions. Therefore, it is preferable that the shift restriction is performed while the current shift mode is in neither of the two modes. If it is determined that the predetermined shift restriction condition exists in step S214, the transmission control unit 50 determines whether a current shift range is a forward driving range in step S214. The forward driving range may include a driving D range, a third speed 3 range, a second speed 2 range, a first speed 1 range (or a low speed L range), and it may further include a sports SP mode in a transmission that is provided with a sports mode. If it is determined that the current shift range is a forward driving range in step S214, the transmission control unit 50 performs a predetermined shift restriction control for a predetermined shift restriction period (for example, 1 second). The transmission control unit 50 determines whether shifting is in progress in step S216, and if it is, the transmission control unit 50 controls to complete the progressing shift. The transmission control unit 50 determines whether a shift range is converted into a neutral N range or a park P range from the forward driving range during the predetermined shift restriction period in step S218, and if it is, the transmission control unit 50 controls to shift the shift speed into N(3) in step S230. The transmission control unit 50 then stops the progress of the predetermined shift restriction time period. The N(3) designates a third gear in the neutral N range. Further, the transmission control unit 50 performs the progressing shift control in step S220 if the shift range has not been shifted into the neutral N range nor the park P range in step S218. Then, the transmission control unit 50 determines whether the progressing shift has been completed in step S222, and if it has, the transmission control unit 50 performs a shift restriction control in steps S224 to S228 for the predetermined shift restriction time (for example, one second). Moreover, when the shift range is shifted into N-range or P-range, the transmission control unit 50 controls to shift the shift range into N (3) (S232 and S234). Then, the transmission control unit 50 determines whether N→ D shifting occurs in step S236, and if it is determined that N→ D shifting occurs, the transmission control unit 50 controls to shift the shift range into range D(3), which designates a third gear in the driving D range in step S238. When N→ D(3) shifting is completed, the transmission control unit 50 performs the shift restriction control of steps S224 to S228 for the predetermined shift restriction time (for example, one second). The shift restriction control is identical to the predetermined shift control of FIG. 1, which corresponds to step S116 to S120. That is, the transmission control unit 50 controls to maintain a current shift speed without down-shifting if a predetermined down-shift condition exists in step S224. Then, the transmission control unit 50 determines whether the predetermined up-shift condition exists in step S226. If it is determined that the predetermined up-shift condition exists in step S226, the transmission control unit 50 controls to up-shift the shift speed into one speed higher than a current shift speed if a predetermined up-shift condition exists in step S228. The predetermined up-shift condition has already been described in the above. Referring to FIG. 3, the output-shaft speed sensor diagnostic method based on signals of the input-shaft speed sensor 20, the output-shaft speed sensor 30, and the engine speed sensor 40 will be described hereinafter. The output-shaft diagnosis of FIG. 3 corresponds to steps S110 to S114 of FIG. 1. The transmission control unit 50 determines whether a current shift range is a forward driving range in step S310, and if it is, the transmission control unit 50 determines whether a current shift speed is a first shift speed (including range L) or a second shift speed in step S312. If it is determined that the current shift speed is the first shift speed or the second shift speed in step S312, the transmission control unit 50 determines whether a predetermined failure determination condition exists in step S314 to S320. When the current shift speed is the first shift speed or the second shift speed, the predetermined failure determination condition comprises: (1) {a predetermined period (for example, 3 seconds) passage after N→ D shifting} & {a turbine speed (an input-shaft speed) Nt > a predetermined turbine speed SNt1 (for example, 700 RPM)} & {no pulse signal of the output-shaft speed sensor 30}; or (2) {a predetermined period (for example, 3 seconds) passage after N→ D shifting} & {an engine speed Ne > a predetermined engine speed SNe1 (for example, 3000 RPM)} & {a normality of an output signal of the engine speed sensor} & {no pulse signal of the output-shaft speed sensor 30}. Therefore, if at least one condition of the two conditions exists when the shift speed is the first shift speed or the second shift speed, the transmission control unit 50 determines that the output-shaft speed sensor 30 has failed, and generates a corresponding diagnosis signal. The predetermined period after N→ D shifting may be set as a period for engaging gears for N→ D shifting under a cold temperature. If a turbine speed is approximately 700 RPM when a shift speed is the first shift speed or the second shift speed, the output-shaft of the transmission may be considered to rotate. Therefore, if there is no pulse signal of the output-shaft speed sensor under the condition (1), this may indicate the failure of the output-shaft speed sensor 30. Similarly, if an engine speed is approximately 3000 RPM when a shift speed is the first shift speed or the second shift speed, the output shift of the transmission may be considered to rotate. Therefore, if there is no pulse signal of the output-shaft speed sensor under the condition of (2), this may indicate failure of the output-shaft speed sensor 30. Furthermore, in condition (2), the predetermined engine speed 3000 RPM is determined in consideration of an engine stall speed. An engine stall test is generally performed under a first shift speed, and the engine stall speed is about 2700-2800 RPM. If the engine speed is higher than the engine stall speed at the first shift speed, the output-shaft of the transmission is considered to rotate. The predetermined engine speed is determined to be higher than the engine stall speed at the first shift speed, so if there is no pulse signal of the output-shaft speed sensor under the condition (2), this may indicate failure of the output-shaft speed sensor 30. In condition (2), the normality of the engine speed sensor signal may be diagnosed by a separate control logic, and such control logic may easily be performed by a person skilled in the art. In order to determine whether the predetermined failure determination condition exist when the shift speed is a first shift speed or a second shift speed, the transmission control unit 50 determines whether the predetermined period has elapsed after N→ D shifting in step S314 if it is determined that the current shift speed is a first shift speed or a second shift speed in step S312. If the predetermined period has elapsed in step S314, the transmission control unit 50 determines whether the current turbine speed Nt is higher than the predetermined turbine speed SNt1 in step S316. If the turbine speed is higher than the predetermined turbine speed, the transmission control unit 50 determines whether a pulse signal of the output-shaft speed sensor is input in step S318. If a pulse signal of the output-shaft speed sensor is not input, that is, an output-shaft speed, which is detected by the output-shaft speed sensor 30, is 0, it is determined that the output-shaft speed sensor has failed, so the transmission control unit 50 generates a corresponding failure signal in step S320. Meanwhile, if the turbine speed is not higher than the predetermined turbine speed in step S316, the transmission control unit 50 determines whether the engine speed Ne is higher than the predetermined engine speed SNe1 in step S322. If the engine speed is higher than the predetermined engine speed, the transmission control unit 50 determines whether the engine speed signal is in a normal state in step S324. Then, the procedure advances to step S318, and if it is determined that a pulse signal is not input from the output-shaft speed sensor, it is determined that the output-shaft speed sensor has failed, so the transmission control unit 50 generates a corresponding failure signal in step S320. If it is determined that the current shift speed is neither a first shift speed nor a second shift speed of the forward driving range in step S312, the transmission control unit 50 determines whether a current shift speed is a third shift speed, a fourth shift speed, or a fifth shift speed in step S326, and if it is, the transmission control unit 50 determines whether a predetermined failure determination condition exists. When the current shift speed is a third shift speed, a fourth shift speed, or a fifth shift speed, the predetermined failure determination condition comprises: (1) {after termination of N→ D shifting} & {a turbine speed (an input-shaft speed) Nt > a predetermined turbine speed SNt2 (for example, 700 RPM)} & {no pulse signal of the output-shaft speed sensor 30}; or (2) {after termination of N→ D shifting} & {an engine speed Ne > a predetermined engine speed SNe2 (for example, 2000 RPM)} & {a normality of an output signal of the engine speed sensor} & {no pulse signal of the output-shaft speed sensor 30}. Therefore, if at least one condition of the three conditions exists when the shift speed is a third shift speed, a fourth shift speed, or a fifth shift speed, the transmission control unit 50 determines that the output-shaft speed sensor 30 has failed, and generates a corresponding diagnosis signal. The transmission control unit 50 determines whether a current shift speed is a third shift speed, a fourth shift speed, or a fifth shift speed in step S326, and if it is, the transmission control unit 50 determines whether N→ D shifting has been terminated in step S328. If N→ D shifting has been terminated, the transmission control unit 50 determines whether the turbine speed Nt is higher than the predetermined turbine speed SNt2 in step S330. If the turbine speed is higher than the predetermined turbine speed in step S330, the transmission control unit 50 determines whether a pulse signal of the output-shaft speed sensor has been input in step S318. If the pulse signal of the output-shaft speed sensor has not been input, it is determined that the output-shaft speed sensor has failed, so the transmission control unit 50 generates a corresponding failure signal. Meanwhile, if the turbine speed is not higher than the predetermined turbine speed in step S330, the transmission control unit 50 determines whether the engine speed Ne is higher than the predetermined engine speed SNe2 in step S332. If the engine speed is higher than the predetermined engine speed, the transmission control unit 50 determines whether the engine speed signal is normal in step S334, and if it is, the procedure advances to step S318. If a pulse signal of the output-shaft speed sensor 30 has not been input in step S318, it is determined that the output-shaft speed sensor has failed, so the transmission control unit 50 generates a corresponding failure signal in step S320. If it is determined that the output-shaft speed sensor has failed, the transmission control unit 50 performs a predetermined shift control for the predetermined period of time. That is, if a predetermined down-shift condition exists, the transmission control unit 50 maintains a current shift speed without down-shifting, and if the predetermined up-shift condition exists, the transmission control unit 50 upshifts the shift speed into one speed higher than a current shift speed. Moreover, if the condition of judging a failure of the output-shaft speed sensor and the conditions of judging the shift restriction are satisfied, the transmission control unit 50 stops the progress of the predetermined time and stores the conditions for 1 second in the case of continuously satisfying the conditions. If the output-shaft speed sensor is determined to have failed more than a predetermined number of times (for example, 4 times), the transmission control unit 50 controls to operate a fail-safe mode in which a shift speed is held at a predetermined shift speed. For example, the transmission control unit 50 controls to operate the fail-safe mode of third gear when it judges the failure of the output-shaft speed sensor in range D, range 4, or range 3, and to operate the fail-safe mode of second gear when it judges the failure of the output-shaft speed sensor in range 2 and range N. As described above, an embodiment of the present invention may improve stabilization by inserting the shift restriction logic with the judging of a failure of the output-shaft speed sensor as an input-shaft speed sensor or with using an angular acceleration value (dNo/dt) of the output-shaft speed sensor, and judge a failure by using an engine rotary speed in spite of the failure of an input-shaft speed sensor. Particularly, an embodiment of the present invention may prevent the misjudgment of a stall test by setting a basic engine rotary speed according to the respective shift ranges, and it may judge a failure even below a stall rotary speed in the second gear, a third gear, and a fourth gear at the same time, and judge the failure of the output-shaft speed sensor in spite of a failure of the input-shaft speed sensor. As described above, a system for diagnosing failure of an output-shaft speed sensor of an automatic transmission for a vehicle according to an embodiment of the present invention may prevent misjudgment of a failure of an output-shaft speed sensor, and improve the stabilization of a vehicle in spite of a concurrent failure of an input-shaft speed sensor and an output-shaft speed sensor which both may have the same electrical ground. Although preferred embodiments of the present invention have been described in detail hereinabove, it should be clearly understood that many variations and/or modifications of the basic inventive concepts herein taught which may appear to those skilled in the present art will still fall within the sprit and scope of the present invention, as defined in the appended claims. We Claim: 1. A system for diagnosing a failure of an output-shaft speed sensor of an automatic transmission, comprising: an inhibitor switch detecting a shift range; an input-shaft speed sensor detecting a turbine speed and generating a corresponding signal; an output-shaft speed sensor detecting an output-shaft speed of the automatic transmission and generating a corresponding signal; an engine speed sensor detecting an engine speed and generating a corresponding signal; and a control unit diagnosing a failure of the output-shaft speed sensor on the basis of signals of the inhibitor switch, the input-shaft speed sensor, the output-shaft speed sensor, and the engine speed sensor, the control unit being programmed to execute a diagnostic control comprising: determining whether a current shift range is a forward driving range; determining whether a predetermined failure determination condition exists based on a current shift speed, an input-shaft speed, an output-shaft speed, and an engine speed, if the current shift range is the forward driving range; and maintaining the current shift speed if a predetermined down-shift condition exists, or up-shifting a shift speed if a predetermined up-shift condition exists, if the predetermined failure determination condition exists; optionally having shift restriction control comprising: determining whether a predetermined shift restriction condition exists; determining whether the current shift range is the forward driving range, if it is determined that the predetermined shift restriction condition exists; and maintaining the current shift speed if a predetermined down-shift condition exists, or up-shifting a shift speed if a predetermined up-shift condition exists, for a predetermined shift restriction period, if the current shift range is the forward driving range. 2. The system as claimed in claim 1, wherein if the current shift speed is a first shift speed or a second shift speed, the predetermined failure determination condition comprises at least one of: (1) {an elapse of a predetermined period after N→ D shifting} & {a turbine speed > a predetermined turbine speed} & {no pulse signal of an output-shaft speed sensor}; and (2) {an elapse of a predetermined period after N→ D shifting} & {an engine speed > a predetermined engine speed} & {a normalcy of an engine speed sensor signal} & {no pulse signal of an output-shaft speed sensor}. 3. The system as claimed in claim 2, wherein the predetermined engine speed is higher than an engine stall speed of a first shift speed. 4. The system as claimed in claim 1, wherein if the current shift speed is a third shift speed, a fourth shift speed, or a fifth shift speed, the predetermined failure determination condition comprises at least one of: (1) {a termination of N→D shifting} & {a turbine speed > a predetermined turbine speed} & {no pulse signal of an output-shaft speed sensor}; and (2) {a termination of N→D shifting} & {an engine speed > a predetermined engine speed} & {a normalcy of an engine speed sensor signal} & {no pulse signal of an output-shaft speed sensor}. 5. The system as claimed in claim 4, wherein the predetermined engine speed is less than an engine stall speed of a first shift speed. 6. The system as claimed in claim 1, wherein the predetermined up-shift condition comprises at least one of: (1) {an engine speed > a predetermined engine speed} & {an angular acceleration of an engine > 0}; and (2) {a turbine speed > a predetermined turbine speed} & {an angular acceleration of a turbine shaft > 0}. 7. The system as claimed in claim 1, wherein the predetermined shift restriction condition comprises that a turbine speed is higher than a predetermined turbine speed, and an angular acceleration of an output-shaft is less than a predetermined angular acceleration. 8. The system as claimed in claim 7, wherein the predetermined shift restriction condition further comprises that a current shift mode is neither an extremely low temperature mode nor a fail-safe mode. 9. The system as claimed in claim 1, wherein the shift restriction control further comprises shifting a transmission into a third shift speed if a neutral range or a parking range is detected during the predetermined shift restriction period. 10. The system as claimed in claim 1, wherein the shift restriction method further comprises: determining whether the current shift range is a neutral range or a parking range, if it is determined that the current shift range is not a forward driving range; and shifting a transmission into a third shift speed of a neutral range, if the current shift speed is the neutral range or the parking range. 11. The system as claimed in claim 10, wherein the shift restriction control further comprises shifting the transmission into a third shift speed of a driving range if the shift range is shifted into a driving range. 12. The system as claimed in claim 1, wherein the predetermined up-shift condition of the shift restriction control comprises: (1) {an engine speed > a predetermined engine speed} & {an angular acceleration of an engine > 0}; and (2) {a turbine speed > a predetermined turbine speed} & {an angular acceleration of a turbine shaft > 0}. 13. The system as claimed in claim 1, wherein if shifting is in progress when the predetermined shift restriction condition exists, the predetermined shift restriction period starts after the termination of the progressing shift.

Documents:

1040-del-2002-abstract.pdf

1040-DEL-2002-Claims-(30-06-2011).pdf

1040-del-2002-claims.pdf

1040-DEL-2002-Correspondence Others-(30-06-2011).pdf

1040-del-2002-correspondence-others.pdf

1040-del-2002-correspondence-po.pdf

1040-del-2002-description (complete).pdf

1040-del-2002-drawings.pdf

1040-del-2002-form-1.pdf

1040-del-2002-form-18.pdf

1040-del-2002-form-2.pdf

1040-DEL-2002-Form-3-(30-06-2011).pdf

1040-del-2002-form-3.pdf

1040-del-2002-form-5.pdf

1040-DEL-2002-GPA-(30-06-2011).pdf

1040-del-2002-gpa.pdf

1040-DEL-2002-Petition-137-(30-06-2011).pdf