JPH0586491B2 - - Google Patents

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention relates to a control device for a vehicle electromagnetic clutch that is installed in a transmission system from an engine, and more specifically, the invention relates to a control device for a vehicle electromagnetic clutch that is installed in a transmission system from an engine, and more specifically, the invention relates to a control device for a vehicle electromagnetic clutch that is installed in a transmission system from an engine. This relates to drag current control when the driving ranges of Drive D, Sporty Drive Ds, or Reverse R are selected in the combination.

[Conventional technology]

In a vehicle equipped with an electromagnetic clutch, there is conventional technology regarding current control after the shift lever is operated, such as in Japanese Patent Application Laid-Open No. 57-160731 and Japanese Patent Application Laid-open No. 57-15023. It has been proposed to increase the current smoothly to reduce shock when the clutch is engaged.

By the way, a transmission system that combines the above-mentioned electromagnetic clutch with a belt-type continuously variable transmission has already been proposed, and even in this case, clutch pedal operation is controlled by electrically controlling the clutch torque of the electromagnetic clutch. This has advantages such as eliminating the need for Belt-type continuously variable transmissions have the greatest advantage of continuously variable speed, but on the other hand, there are various issues that must be resolved before they can be installed in a vehicle and utilized to the maximum extent possible. In this case, various proposals have been made to address the problem by utilizing the performance of an electromagnetic clutch that can be electrically controlled.

[Problem to be solved by the invention]

One of the problems with the belt-type continuously variable transmission is the static friction torque of the belt portion. That is, at the time of starting, the gear ratio is set to be the largest and the belt transmission torque is also large, so the pulley pressing force against the belt is also large, and therefore the static friction torque at the belt portion is large. Therefore, much of the engine power transmitted through engagement of the clutch during start-up is consumed by this static friction torque, resulting in sluggish start-up and the transition from static friction torque to dynamic friction torque. There are rattling sounds and vibrations due to torque changes, as well as rattling sounds from the gears.

In order to deal with this, a small drag torque is already applied to the clutch when the clutch is released before starting, and a small portion of the engine power is transmitted to the continuously variable transmission side and consumed as static friction torque in the belt section. Attempts have been made to reduce the play in the gears.

However, in the transmission system of such an electromagnetic clutch and continuously variable transmission, the switching part that selects from the neutral position of Park P or Neutral N range to the forward gear of D or Ds range, or the reverse gear of R range is continuously variable. For those installed on the input side of a transmission, when this switching section is in the neutral position, the continuously variable transmission is disconnected from the electromagnetic clutch, so drag current control is meaningless. ,
From this, it is only necessary to select the driving range D, Ds, or R and control the drag current to flow while the switching section is engaged and connected by a synchronizing mechanism or the like.

In this case, a switch that detects the operation of the select lever to each range is generally installed at the select lever, and it is desirable to control the drag current based on the operation signal of this switch to each travel range. However, the select lever is a cable,
Because it is connected to the switching mechanism of the switching section via a mechanical link, rotation means, etc., there may be a slight delay in the actual switching operation of the switching section even if the switch near the select lever operates. .

Therefore, at this time, when a drag current begins to flow based on the switch operation of the select lever and a portion of the engine power is transmitted by the drag of the clutch, there is a problem that the load on boring increases and the select force increases.

In view of the problem of drag current control at the time of selection in a transmission system combined with such a continuously variable transmission, the present invention aims to prevent a slight delay in the switching section when drag current control is performed using the operation signal of the select switch. It is an object of the present invention to provide a control device for an electromagnetic clutch for a vehicle, which performs certain switching operations without being affected by drag current and prevents an increase in select force.

[Means to solve the problem]

In order to achieve this object, the present invention provides an electromagnetic clutch in the drive system between the engine and the continuously variable transmission, and controls the starting current, direct current, zero current, or In a vehicle electromagnetic clutch to which a drag current is supplied, the control unit includes a means for determining whether the vehicle is stopped at a vehicle speed below a set speed by releasing the accelerator based on signals from the accelerator switch and the vehicle speed switch, and a means for determining whether the vehicle is stopped at a set vehicle speed or less by using a signal from the select switch 54. means for detecting the selection from the position to the driving range; means for determining a delay time when the driving range is selected from the neutral position when the accelerator is released and the vehicle is stopped at a speed below the set vehicle speed; and means for supplying a drag current to the type clutch.

[Effect]

According to the above-mentioned configuration, even if it is detected that the drive range has been selected when the accelerator is released and the vehicle is almost at a standstill, the timing for supplying the drag current to the electromagnetic clutch occurs after a predetermined delay time has elapsed. In this case, even if the mechanical operation of the switching mechanism of the continuously variable transmission by the select lever is slightly delayed due to backlash, etc., the clutch is in the released state and will not be affected by the drag current, and the select operation will depend on the select force. It will be possible to do this reliably without causing any increase.

〔Example〕

Hereinafter, one embodiment of the present invention will be specifically described with reference to the drawings. In FIG. 2, a transmission system including an electromagnetic clutch to which the present invention is applied will be explained. Reference numeral 1 is an electromagnetic powder clutch, and 2 is a continuously variable transmission. A forward/reverse switching section 3, a pulley ratio converting section 4, and a final reduction section 5 are configured to be transmitted from the side. The electromagnetic powder clutch 1 is housed in one side of the clutch housing 6, and is connected to the other side of the clutch housing 6, the main case 7 connected thereto, and the side of the main case 7 opposite to the clutch housing 6. A switching section 3, a pulley ratio converting section 4, and a final reduction section 5 of the continuously variable transmission 2 are assembled inside the side case 8.

The electromagnetic clutch 1 includes a ring-shaped drive member 12 that is integrally connected to a crankshaft 10 from the engine via a drive plate 11, and a disk-shaped driven member that is integrally spline-coupled to a transmission input shaft 13 in the rotational direction. 14.
A coil 15 is built into the outer peripheral side of the driven member 14, and a gap 16 is formed along the circumference between both members 12 and 14.
6 communicates with a powder chamber 17 containing electromagnetic powder therein. Further, a power feeding brush 19 is in sliding contact with a slip ring 18 of the hub portion of the driven member 14 equipped with the coil 15, and passes through the inside of the driven member 14 from the slip ring 18 to the coil 15.
A clutch current circuit is constructed by connecting the two terminals.

In this way, when a clutch current is passed through the coil 15, electromagnetic powder is bound and accumulated in the gap 16 in a chain form due to the lines of magnetic force generated between the drive and tribe members 12 and 14 through the gap 16. The driven member 14 slides and is integrally connected to the drive member 12 due to the force, resulting in a clutch connected state.

On the other hand, when the clutch current is cut, the drive and driven members 12 and 14 are affected by electromagnetic powder.
The binding force is lost and the clutch becomes disconnected. If the clutch current in this case is controlled in conjunction with the operation of the switching unit 3 of the continuously variable transmission 2, it will be possible to automatically switch from the P or N range to the forward D or Ds or reverse R range. Clutch 1 is then disengaged and clutch pedal operation becomes unnecessary.

Next, in the continuously variable transmission 2, the switching section 3 is provided between the input shaft 13 from the clutch 1 and the main shaft 20 disposed coaxially therewith. That is, the input shaft 13 is formed with a reverse drive gear 21 that also serves as a forward engaged side, and a reverse engaged side gear 22 is rotatably fitted to the main shaft 20. , 22 are a counter gear 24 supported by a shaft 23, and an idler gear 2 supported by a shaft 25.
6 and are interlocked with each other. and the main shaft 20
A switching mechanism 27 is provided between the gears 21 and 22. The above gear 2, which is always in mesh here,
1, 24, 26, 22 are coils 15 of clutch 1
The switching mechanism 27 has a sleeve 29 spline-fitted to the hub 28 of the main shaft 20, which is connected to the driven member 14 having a synchronizer. Each gear 21, 22 via mechanism 30, 31
It is configured to mesh and connect with the

As a result, in the neutral position of the P or N range, the sleeve 29 of the switching mechanism 27 is fitted only with the hub 28, and the main shaft 20 is separated from the input shaft 13. Next, when the sleeve 29 is engaged with the gear 21 side via the synchro mechanism 30, the main shaft 2
0 is directly connected to the forward state of D or Ds range.
On the other hand, when the sleeve 29 is reversely engaged with the gear 22 side via the synchro mechanism 31, the input shaft 13 is connected to the main shaft 20 via the gears 21, 24, 26, 22, and the engine power is decelerated and reversed to shift to the R range. The vehicle will move backwards.

In the pulley ratio conversion unit 4, a sub-shaft 35 is arranged parallel to the main shaft 20, a main pulley 36 and a sub-pulley 37 are provided on both the shafts 20 and 35, respectively, and an endless belt is provided between the two pulleys 36 and 37. A drive belt 34 is stretched over the drive belt 34. Pulley 3
Both pulley halves 36a and 37a are movable in order to make the pulley interval variable, and the movable pulley half body 36b,
Hydraulic servo devices 38 and 39 which themselves also serve as pistons are attached to 37b, and a spring 40 is applied to the movable pulley half 37b of the sub pulley 37 in a direction to narrow the pulley interval.

Further, an oil pump 41 serving as an operating source is installed next to the main pulley 36 as a hydraulic control system. This oil pump 41 is a high-pressure gear pump, and a pump drive shaft 42 passes through the main pulley 36, main shaft 20, and input shaft 13 and is directly connected to the crankshaft 10, so that oil pressure is always generated during engine operation. It's getting old. Then, the oil pressure of the oil pump 41 is controlled to supply and drain oil to each hydraulic servo device 38, 39, and the pulley spacing between the main pulley 36 and the sub pulley 37 is changed to a relationship between the pulleys 3 and 3 of the drive belt 34.
The pulley ratios at 6 and 37 are changed steplessly, and steplessly variable power is output to the subshaft 35.

In view of the fact that the minimum pulley ratio on the high-speed stage side of the pulley converter 4 is very small, for example, 0.5, and therefore the rotation speed of the subshaft 35 is large, the final reduction unit 5 has one set of intermediate pulley ratios for the subshaft 35. An output shaft 44 is connected via a reduction gear 43. A final gear 46 meshes with the drive gear 45 of this output shaft 44,
Power is transmitted from the final gear 46 to the axles 48 and 49 of the left and right drive wheels via the differential mechanism 47.

Referring to FIG. 3, the control system of the electromagnetic powder clutch will be explained. To explain the outline of the present invention, omitting those that are not directly necessary for the present invention, there is a vehicle speed switch 50 that is turned on at a set vehicle speed or higher to detect the vehicle speed, and a switch that is proportional to the engine rotation using, for example, the primary side voltage of the ignition coil. It has an engine rotation sensor 51 that generates pulses, an accelerator switch 52 that turns on only when the accelerator is depressed to detect accelerator operation, and a select switch 54 that is provided at the hand of the select lever, and these output signals are sent to the control unit 53. Operation mode determination section 5
6 is input. The operation mode semi-fixing section 56 is
At least 4 modes depending on each signal (direct connection mode, drag mode, zero mode, start mode, etc.)
The current setting unit 55 outputs a direct current, a drag current, a zero current, or a current proportional to the engine rotation according to each mode to set the clutch coil 1.
5.

Therefore, the operation of the control device configured as described above will be explained using the flowchart shown in FIG. In the case of selection, the timer is started. On the other hand, if depression of the accelerator is detected by the signal from the accelerator switch 52, or if the vehicle speed switch 50 is turned on at a vehicle speed higher than the set vehicle speed of 5 to 10 km/h even when the accelerator is released, the operating mode determining unit 5
6, it is determined that it is running mode, the count up is immediately started, the direct current, the current proportional to the engine rotation,
Or pass zero current.

On the other hand, when the accelerator is released and the vehicle speed is below the set speed and the vehicle is almost stationary, it is determined that the drag current mode is active, and in this case, the timer is counted.
After the specified time is exceeded, a small drag current is applied. Therefore, in the case of a select operation when the vehicle is approximately stopped, the select lever hand switch 54 is set to D,
Even if it is detected that the driving range Ds or R is selected, the drag current will flow with a delay, and in this case, the mechanical switching mechanism 27 in the switching section 3 of the continuously variable transmission 2 by the select lever Even if the operation is delayed to some extent due to backlash, etc., the operation is performed smoothly when the clutch is released. In the above state, the drag current continues to flow due to the counter holding, and a portion of the engine power is transmitted to the switching section 3 and the belt 34 due to the drag torque generated in the clutch 1. The torque is consumed by static friction, and the gears are cleared to prepare for the start. Therefore, when starting, when the accelerator switch 52 or other signal counts up and enters the driving mode, and when the clutch 1 is engaged and engine power is transmitted, the belt 34 in the continuously variable transmission 2 immediately rotates due to dynamic friction. This makes it possible to start off with a good start.

〔Effect of the invention〕

As is clear from the description of the embodiments above, according to the present invention, in an electromagnetic clutch combined with a continuously variable transmission, drag current is controlled when selecting a driving range when the vehicle is substantially stopped. To,
Since the timing at which the drag current flows is delayed by a predetermined period of time, even if the operation of the switching section 3 is delayed a little, it will not be affected by the drag current, and the selection operation can be performed reliably without increasing the selection force. I can.

In addition, since the drag current is maintained under the above conditions, the engine power is transmitted smoothly in any start, making it more effective. Since the timing is determined in relation to the mode, there is no confusion between the two.

[Brief explanation of drawings]

FIG. 1 is a functional block diagram showing a control device for a vehicle electromagnetic clutch according to the present invention, FIG. 2 is a sectional view showing an example of a transmission system of an electromagnetic clutch to which the present invention is applied, and FIG. 3 is a functional block diagram showing a control device for a vehicle electromagnetic clutch according to the present invention. FIG. 4 is a block diagram showing an embodiment of the apparatus according to the present invention, and FIG. 4 is a flowchart diagram explaining the operation. 1... Electromagnetic powder clutch, 2... Continuously variable transmission,
15...Clutch coil, 50...Vehicle speed switch, 51...Engine rotation sensor, 52...Accelerator switch, 53...Control unit, 54...
Select switch.

Claims (1)

[Claims] 1. An electromagnetic clutch is provided in the drive system between the engine and the continuously variable transmission, and a starting current, a direct current, a zero current, or a drag current is controlled via a control unit 53 depending on the vehicle running condition. In the supplied vehicle electromagnetic clutch, the control unit 53 includes an accelerator switch 52.
Means 6 for determining whether the vehicle is stopped at a vehicle speed below a set vehicle speed by releasing the accelerator, based on signals from the vehicle speed switch 50 and the vehicle speed switch 50;
0 and means 6 for detecting selection from the neutral position to the travel range based on the signal from the select switch 54.
1, means 62 for determining a delay time when the drive range is selected from the neutral position when the vehicle is stopped at a vehicle speed below a set speed with the accelerator being released; and means 62 for supplying drag current to the electromagnetic clutch after the delay time has elapsed. 63. A control device for an electromagnetic clutch for a vehicle, comprising: