JPH0573354U - Lockup control device for torque converter - Google Patents

Abstract

(57) [Summary] [Purpose] In a vehicle having a brake system equipped with a hydraulic booster by a hydraulic pump directly connected to the engine and a torque converter with lockup by a direct clutch, even if the vehicle stalls at high speed The purpose of the present invention is to operate the brake hydraulic booster even at a vehicle speed at which the brake hydraulic booster is required or higher, even without the ground driven hydraulic pump. [Structure] A sensor 3 for detecting an engine speed, a sensor 9 for detecting a vehicle speed, and a controller 20 for controlling a lockup are provided, and the vehicle travels at a vehicle speed equal to or higher than a safe vehicle speed even if a hydraulic booster for a brake is not operated. It is characterized in that when the engine speed reaches a speed close to stop, a lock-up ON signal is output from the controller 20 to turn on the direct coupling clutch.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a wheeled vehicle such as a mobile crane, which has a brake system including a hydraulic booster by a hydraulic pump directly connected to an engine and a torque converter with a lockup by a direct coupling clutch.

[0002]

[Prior Art]

 In the above vehicles, conventionally, when the driver actuates the lockup switch when the vehicle speed or engine speed reaches a predetermined value, the direct coupling clutch of the torque converter operates, The input shaft and output shaft of the torque converter are directly connected (locked up). When the vehicle speed or engine speed falls below a predetermined level, the direct coupling clutch is cut off and the torque converter (fluid coupling) works.

[0003]

[Problems to be solved by the device]

 In the above-mentioned conventional vehicles, if the engine stops due to running out of fuel during high-speed driving, etc., the direct coupling clutch will disengage when the vehicle speed falls below the specified speed even if the direct coupling clutch is operating and is in the lockup state. There is a problem that the driving force of the hydraulic pump is lost and the hydraulic booster for the brake is ineffective, resulting in a significant decrease in control force. The predetermined vehicle speed is a dangerous speed unless the brake booster operates normally at a speed of 20 km / H or more for reasons such as reduction of shift shock. In order to deal with this problem, it was necessary to separately provide a hydraulic pump directly connected to the axle and driven by the tire (hereinafter referred to as a grand driven hydraulic pump).

[0004]

[Means and Actions for Solving the Problems]

 This invention has been made in view of the above, and detects the engine speed in a vehicle having a brake system equipped with a hydraulic booster by a hydraulic pump directly connected to the engine and a torque converter with lockup by a direct clutch. By providing a sensor, a sensor that detects the vehicle speed, and a controller that controls the lockup, the engine speed that is close to the stop of the engine while the vehicle is running at a speed higher than the safe vehicle speed even if the brake hydraulic booster does not operate. When this happens, the controller sends a lock-up-on signal so that the direct coupling clutch is engaged.

[0005]

【Example】

 An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a system configuration diagram of a torque converter lockup control device according to the present invention, and FIG. 2 is a logic diagram for explaining an output condition of the controller 20 in FIG. In the figure, an engine speed detection sensor 3 is provided on an output shaft 2 of an engine 1, the output shaft 2 is connected to a pump 51 of a torque converter 5 via a direct coupling clutch 4, and a turbine 52 is a torque converter output shaft. A torque converter output shaft rotation speed detection sensor 7 is provided on the output shaft 6. Further, the torque converter output shaft 6 is connected to an axle 8, and a vehicle speed detection sensor 9 is provided on the axle 8.

The direct coupling clutch 4 is switched on and off by the direct coupling clutch control valve 10. Reference numeral 11 is a hydraulic pump for actuating a brake booster (not shown) and the direct coupling clutch 4.

Information signals from the engine speed detecting sensor 3, the torque converter output shaft speed detecting sensor 7, and the vehicle speed detecting sensor 9 are input to the controller 20 through the electric signal lines 21, 22 and 23, respectively. The output signal from the controller 20 is output to the direct coupling clutch control valve 10 through the electric signal line 24.

Next, the output condition of the controller 20 will be described with reference to FIG. Fig. 2 shows the case of the conventional lockup ON (the direct clutch 4 is engaged) (when the vehicle speed or engine speed reaches a predetermined value, or when the driver locks up with a switch), or the following 2 Two conditions (1) Engine speed ≤ α (unusual engine speed except during engine stall, 550 rpm or less for normal diesel engine) (2) Vehicle speed ≥ β (0 to 20 km / h, hydraulic boost of brake) It indicates that the lock-up on signal is output when the vehicle speed is satisfied even if the device does not operate.

As described above, in this embodiment, even if the engine stalls while the vehicle is traveling at high speed, the lockup is turned on under the conditions (1) and (2), so that the engine is on the axle side. The hydraulic pump directly connected to the engine will be in the same state as the ground driven, the brake hydraulic booster will operate, and the brake hydraulic booster can be operated until the vehicle speed falls below β. As a result, the safety of the vehicle running can be fully maintained.

[0010]

[Effect of the device]

 Since the present invention is configured as described above in detail, even if an engine stalls due to running out of fuel while the vehicle is running at high speed, the hydraulic booster of the brake operates, which greatly increases the safety of the vehicle. It will improve.

[Brief description of drawings]

FIG. 1 is a system configuration diagram of an embodiment of the present invention.

FIG. 2 is a logic diagram for explaining output conditions of the controller in FIG.

[Explanation of symbols]

 3 Engine speed detection sensor 4 Direct coupling clutch 5 Torque converter 9 Vehicle speed detection sensor 20 Controller

Claims (1)

[Scope of utility model registration request] 1. In a vehicle having a brake system equipped with a hydraulic booster by a hydraulic pump directly connected to an engine, and a vehicle having a torque converter with lock-up by a direct clutch, a sensor 3 for detecting an engine speed and a sensor for detecting a vehicle speed. 9 and a controller 20 for controlling lock-up are provided, and when the engine speed is close to the stop speed while the vehicle is traveling at a vehicle speed higher than a safe vehicle speed even if the brake hydraulic booster does not operate, the controller A lockup control device for a torque converter, characterized in that a lockup ON signal is output from 20 to turn on a direct coupling clutch.