JPS6049792B2 - Shift control mechanism of a transmission with a fluid torque converter having a direct connection stage - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention includes a fluid torque converter between an engine and a transmission, and a high-speed clutch for a direct-coupled gear in the transmission;
The present invention relates to a speed change control mechanism for a transmission with a fluid torque converter having a direct-coupling gear, in which a low-speed clutch is provided for the torque converter-passing gear, and the direct-coupling gear and the torque converter-passing gear can be freely selected by hydraulic switching to the clutch.

Conventionally, fully automatic transmissions with torque converters, which are generally installed in luxury passenger cars, have a direct gear.

In that case, (1) the hydraulic circuit and its control circuit become complicated; (2) Problems such as the inability to make individual switching according to the driver's will (preference) are unavoidable.

As a countermeasure to this problem, if a semi-automatic transmission is installed in which the engine and the transmission are directly connected to each other without going through a fluid torque converter, and the direct gear is manually switched, (1) If you decelerate to a stop, the engine will also stop.
(2) If the vehicle is carelessly shifted to a low gear (L) while driving at high speed, the engine may overrun, and in the worst case scenario, such as a motorcycle, the shock may cause the vehicle to fall over. The present invention incorporates a direct coupling stage to improve fuel efficiency when driving at medium and high speeds.
It is an inexpensive device that works effectively and safely, maintains the advantage of semi-automatic transmissions that can change gears at any time according to the driver's will, and prevents the danger of gear shifting mistakes, and also prevents the driver from decelerating to a stop because he or she forgets that he or she has shifted to the direct gear. There are methods to prevent the engine from stalling.

Next, it will be explained with reference to the drawings.

FIG. 1 is a schematic horizontal cross-sectional view of an engine/transmission combination of a motorcycle as an example to which the present invention can be applied, in which 1 is an engine, 2 is a fluid torque converter, and 3 is a transmission. A sprocket 5 fixed to the right end of the crankshaft 4 and a sprocket 6 fixed to the right end of the pump impeller 18 of the torque converter 2 are connected by a chain 7 to the turbine shaft 8 (first shaft) of the torque converter 2 at low speed. A stage drive gear 11 is integrally attached.
Further, a high speed (directly connected) stage drive gear 9 integrally connected to the pump impeller 18 and the sprocket 6 is rotatably mounted. The low-speed drive gear 11 meshes with a driven gear 13 on the second shaft 12 and is connected to the second shaft 12 via the low-speed clutch 10. An output sprocket 14 on the second shaft 12 is connected to a rear wheel sprocket (not shown) via a chain 15. The input side driven gear 17 of the direct-coupling high speed clutch 16 meshes with the drive gear 9, and the second shaft 12 also serves as the output shaft of the high speed clutch 16. When hydraulic pressure is supplied only to the low speed clutch 10, the first shaft 8 and the second shaft 12 are connected via the gears 11 and 13, and the low speed range L (low) is established. When hydraulic pressure is supplied only to the high-speed clutch 16, the pump impeller 18 and shaft 12
are directly connected via gears 9 and 17 without fluid, resulting in a high speed range H (high...directly connected). Specifically, the features of the present invention are as follows in the power unit shown in FIG.
(1) At a vehicle speed of Bkm/Hr (for example, about 90 km/Hr) or higher, even if an attempt is made to shift to L (low), the gear does not change (the low-speed clutch 10 does not engage).

(2) Even if it is set to H (direct connection), the vehicle speed is Akm/Hr.
(for example, about 30 km/h), it will automatically return to L (only the hydraulic circuit will change, and the shift pedal, shift lever, etc. will not move). (3) H (direct connection) when the vehicle speed is less than a
Prevents the switch from shifting even if you try to upshift.

In other words, the vehicle speed V is greater than or equal to Akm/Hr and less than Bkm/Hr.
(For example, when 30≦V<90), L.
and H can be switched at any time, but it is fixed when it is less than Akm/Hr and more than Bkm/Hr (circuit-wise, L
Although it is possible to drive at more than Bkm/Hr as it is, the engine will overrun if the driver notices this and shifts up. ).

There is no mechanism to automatically switch to H (direct connection) even if the speed exceeds Bkm/Hr while in L. The second one showing an example of the circuit? SL is a low-speed changeover switch, and SH is a high-speed changeover switch, both of which return to the 0FF side shown in the figure when the manual, manual, or foot actuating force disappears.

RL'' is the normal O of the low speed relay (RL...not shown)
With the N contact, if the low speed relay is energized, the contact RL'' will be 0.
Becomes FF. RH'' is a contact (normally OFF) of a high-speed relay (RH...not shown), and when the high-speed relay is energized, the contact RH'' becomes 0N. RN is a low speed detection contact linked to the vehicle speed detector, and becomes 0FF when the vehicle speed is more than Akm/Hr and less than 0N1. RB'' is a high-speed detection contact that is linked to the vehicle speed detector, and is 0 when the vehicle speed is over Bkm/Hr and less than 0FF1.
It becomes N. The vehicle speed detector consists of a non-contact limit switch installed on a speedometer, etc. V is a solenoid valve that switches the hydraulic pressure to the clutch, and normally (when 0FF) maintains L (low speed range), which supplies hydraulic pressure to the low speed clutch, and establishes H (high speed range) when energized. Further, 20 in FIG. 2 is a power source. Figure 2 shows vehicle speed Akm/
Show the state when it is less than Hr. The solenoid valve V is returned to L (low speed range) by the force of the spring.

The structure of the solenoid valve V in FIG. 2 is shown in FIG. 3. The solenoid valve Vs in FIG. 3 is energized and returned to the right by the elasticity of the spring 21,
3 are connected. 24 is a valve for switching between N (neutral) and D (drive), and an oil device 25 communicates with a pressure regulating valve.

26 is an oil passage communicating with the high speed clutch 16.

Since the switching valve 24 is in the drive range (D), the oil passages 25, 22, and 23 are in communication, oil pressure is supplied to the low speed clutch 10, and L (low speed range) is established. When the solenoid valve s is energized, the solenoid valve V and the spring 21
The oil passages 22 and 26 communicate with each other to establish H (high speed range). The low/high speed changeover switches SL, SH may be pressed by an arm 29 provided on the change pedal 28 as shown in FIG.

That is, when the change pedal 28 is shifted up, the high speed changeover switch SH is turned on, and when the change pedal 28 is shifted down, the low speed changeover switch SL is turned on. As shown in FIG. 5, the shifting operation may be performed using a shift lever 30 provided near the handle grip. FIG. 6 shows an example in which two push buttons 31 and 32 are provided. As mentioned above, FIG. 2 shows a state where the vehicle speed is less than Akm/Hr.

That is, the vehicle remains in this state from immediately after the engine key is turned on and the main switch is turned on until the vehicle speed reaches Akm/Hr. Vehicle speed detector installed in speedometer, etc. (not shown)
The relay connected to 0FF. ．． R
B" is ON. (1) Now the state shown in Figure 2 (Ak
Even if the switch SH is pressed to switch to H (less than m/Hr), the low speed detection switch RN is set to OFF, so the solenoid valve (8) is not energized and remains in L (low speed range).

(2) When the vehicle speed is greater than or equal to a and less than b.

In this state, both switches RN and RB'' are 0N as shown in Fig. 7. (2.1) When changing from L to H: When the manual switch SH is pressed, a circuit is established instantly and the solenoid valve s is turned on. In Figure 7, move to the left side and send hydraulic pressure to the H clutch to set the H range.At the same time, the high speed relay RH is also energized, so its contact RH'' also becomes 0N, even if you release the switch SH and set it to 0FF. The circuit is self-maintained at a high level (Figure 8).

(2.2) When changing from H to L: When the manual switch SL is pressed in the state of (2.1) above (Fig. 8), the low speed relay RL is energized and its contact RL'' becomes 0.
Since it becomes FF, the solenoid valve (■) becomes 0FF, and returns to the right due to the splash and becomes L (Fig. 7).

At the same time, relay RH is no longer energized, so contact RH
'' becomes 0FF and remains at L even if switch SL is released. (3) When the vehicle speed naturally falls below a (3.1) H, the state of (2.1) (the From Figure 8), when the solenoid valve Vs is energized, the vehicle speed decreases,
When it becomes less than Akm/Hr, contact RN becomes 0FF,
It will automatically become L.

(3.2) When the vehicle speed drops below Akm/Hr while the solenoid valve is at L, the solenoid valve s is not energized to begin with, so it remains at L (Figure 7).

(4) Vehicle speed Bkm/Hr or more. In this state, contact RN is 0N. ．． RB'' is 0FF (Fig. 9).At this time, when switching from H to L, even if the switch SL is pressed, the contact R is
Since B'' is 0FF, relay RL is energized and H is maintained.As explained above, according to the present invention, (1)
If the vehicle speed is over Bkm/Hr (approximately 90km/Hr), the gear will not shift even if you try to downshift to L.

(2) Even if it is in H (direct connection), the vehicle speed is Akm/Hr (
(approximately 30 km/h), it will automatically return to L (only the hydraulic circuit will change, and the shift pedal, shift lever, etc. will not move).

(3) If the vehicle speed is less than Akm/Hr (approximately 30 km/Hr), even if an attempt is made to shift up to H (direct connection), the shift will not occur.

As a result, the direct coupling stage, which is incorporated to improve fuel efficiency during medium and high speed driving, can be used effectively and safely with inexpensive equipment.

In addition, while retaining the advantages of a semi-automatic transmission that allows the driver to shift gears at any time according to his/her will, there is an advantage in preventing the risk of gear shifting errors and reliably preventing engine stalling when decelerating due to forgetting that the gear has been shifted to the direct gear. . Separate the N (neutral) and D (drive) switching devices (levers, grips, pedals, etc.) from the L (low) and H (high direct connection) switching devices (levers, grips, pedals, buttons), etc. This is preferable in terms of preventing erroneous operation and simplifying the structure.

The explanation above has been given using an example of a two-speed transmission having H (direct gear) and L (low gear...via a torque converter), but it is also possible to have multiple low gears via a torque converter. It can also be used when adding manual gears to an existing automatic transmission that has multiple gears via a torque converter. That is, in these cases, the present invention can be effectively utilized for switching between the highest speed gear and the direct gear via the torque converter.

[Brief explanation of the drawing]

FIG. 1 is a schematic horizontal cross-sectional view of an engine/transmission combination of a motorcycle as an example to which the present invention can be applied;
Figure 2 is a circuit diagram, Figure 3 is a schematic diagram of the structure of the solenoid 5-id valve, Figures 4 to 6 are schematic diagrams of the structure of the changeover switch, and Figures 7 to 9.
The figure is an explanatory diagram of the operation. 1...Engine, 2...Fluid torque converter, 3...Transmission, 10...Low speed clutch, 16θ...High speed clutch.

Claims (1)

[Claims] 1 A fluid torque converter is installed between the engine and the transmission, and the transmission includes a high-speed clutch for the direct gear and a low-speed clutch for the gear via the torque converter.Hydraulic switching to the clutch allows the transmission to be connected between the direct gear and the gear via the torque converter. In a transmission equipped with a fluid torque converter that has a directly connected gear that can freely select the speed change, the low speed changeover switch SL and the high speed changeover switch SH, which are manual or foot operated, are linked to the vehicle speed detector to change the speed at a low vehicle speed a. A high speed detection contact RB that is linked to the low speed detection contact RA' and the vehicle speed detector and switches at a high vehicle speed.
' and a solenoid valve V that switches the hydraulic pressure to the clutch.
_S, so that when the high-speed clutch is ON, when the vehicle speed becomes less than a, the clutch automatically switches to the low-speed clutch, and when the vehicle speed is above b, the low-speed selector switch is disabled, and when the vehicle speed is less than a, the high-speed selector switch is disabled. A transmission control mechanism characterized by the following.