JPS61215129A - Braking device for vehicles - Google Patents

Abstract

PURPOSE:To make two types of brakes, a service brake and an engine brake, appliable at the same time, by storing a relationship between a brake pedal position and a desired engine speed in a setter in advance, and then controlling the discharge of a shifting hydraulic pump. CONSTITUTION:A service brake 8 is installed in an output shaft 5 of a stepless transmission 2, while a brake pedal detector 10 is installed in a brake pedal 9. An engine speed detector 11 is installed in an input shaft 4 of the transmission 2, while a car speed detector 12 is installed in the output shaft 5 of the transmission 2. And, a desired engine speed ne to a brake pedal position (a) is stored in an engine brake setter 21 of a braking device 1. Likewise, an actual engine speed NE is converged on the desired engine speed ne whereby engine brake force is optionally selectable by brake pedal position operation.

Description

[Detailed description of the invention] [Industrial application field] The present invention relates to a vehicle brake system.

[Conventional technology]

Vehicle transmissions and tracked vehicle transmission steering systems that have a hydrostatic hydromechanical continuously variable transmission mechanism can control the speed ratio and adjust the braking force (engine braking effectiveness) at will, regardless of the vehicle speed. You can choose. Conventionally, this speed ratio control is performed based on the amount of depression of the accelerator pedal. For example, as shown in Fig. 5, in a range where the amount of depression of the accelerator pedal is small, engine braking is activated, and as the amount of depression increases, normal acceleration is applied. The operation is about to take place. When trying to brake the vehicle when there is a brake pedal for normal service brakes, both the engine brake using the accelerator pedal and the service brake using the brake pedal are applied at the same time.
Or they can be operated alternately.

[Problem that the invention seeks to solve]

As mentioned above, when attempting to brake a vehicle with a conventional hydrostatic-mechanical continuously variable transmission mechanism or a tracked vehicle, both the engine brake using the accelerator pedal and the service brake using the brake pedal are operated simultaneously or alternately. As a result, the driving operation becomes complicated.

SUMMARY OF THE INVENTION An object of the present invention is to provide a brake device that eliminates the drawbacks of the conventional example and allows both engine braking and service braking to be operated using only the brake pedal.

[Means and operations for solving the problem] The vehicle brake system of the present invention stores in advance the relationship between the brake pedal position and the Toenson target rotation speed during engine braking in the setting device, and adjusts the discharge of the transmission hydraulic pump. By controlling the amount, the speed ratio is increased or decreased so that the actual engine speed is always driven at the target speed determined by the brake pedal position, so the degree of engine braking can be controlled regardless of the vehicle speed. This allows for arbitrary selection by simply operating the pedals. Therefore, according to this device, both normal service braking and engine braking can be performed by simply operating the brake pedal.
It becomes possible to carry out various types at the same time.

〔Example〕

An embodiment of the present invention will be described below with reference to FIGS. 1 to 4. FIG. 2 is a block diagram of an embodiment of the invention. FIG. 1 is a block diagram of the main components of a brake device according to the present invention. In Figs. 1 and 2, 1 is a brake device, 3 is an engine, 2 is a hydrostatic-mechanical continuously variable transmission, and 5 is its output shaft.

Reference numeral 4 denotes an input shaft of the hydrostatic mechanical continuously variable transmission 2, which is connected to the engine 3. The hydrostatic-mechanical continuously variable transmission 2 has an oil ponzo motor for speed change and a mechanical speed change mechanism that generally includes a plurality of speed stages. 6
is a hydraulic pump discharge amount control actuator for speed change, which is connected to the hydrostatic-mechanical continuously variable transmission 2. Reference numeral 7 denotes an actuator for selecting each speed stage, which is connected to the hydrostatic-mechanical continuously variable transmission 2. Reference numeral 8 denotes a service brake, which is provided on the output shaft 5 of the hydrostatic-mechanical continuously variable transmission 2, and is equipped with a brake pedal 9 and a mechanical, hydraulic, or electrical brake (not shown) in a wide range of depression amount of the brake pedal. It is connected to the. 9 is a brake pedal, and 10 is a brake pedal position detection device provided on the brake pedal 9. Reference numeral 11 denotes a rotation speed detector provided on the input shaft 4 of the hydrostatic mechanical continuously variable transmission 2, and 12 represents a vehicle speed detector provided on the output shaft 5 of the hydrostatic mechanical continuously variable transmission 2. It is set in.

Reference numeral 21 denotes an engine brake setting device that stores the engine target rotation speed relative to the brake pedal position. A is the output of the brake pedal position detector, which is a brake pedal position signal, and is input to the engine brake setting device 21.

22 is a speed deviation detector. n is the engine target rotation speed signal output from the engine brake setting device 21, N
Ii and Ii are engine rotational speed signals output from the engine rotational speed detector 10, and both are input to the speed deviation detector 22.

Δn is the output of the speed deviation detector 22 and is input to the polarity addition circuit 23. No. is a vehicle speed signal output from the vehicle speed detector 12. 24 is a speed ratio calculation circuit which receives the engine speed signal N; and the vehicle speed signal N. is input and a speed ratio signal X is output. 25 is a speed stage logic circuit. A
is a speed stage selection signal outputted from the speed stage logic circuit 25 and inputted to the speed stage selection actuator 7 and the polarity addition circuit 23. Δn8o is a polarized deviation signal and is the output of the polarity adding circuit 23. 26 is an integrator which receives the polarized deviation signal Δ"eo as input. D is a shift hydraulic pump discharge amount control signal, which is the output of the integrator 26 and is input to the shift hydraulic pump discharge amount control actuator 6. Ru.

Next, the operation of the above embodiment will be explained. The hydrostatic-mechanical continuously variable transmission 2 is connected to the engine 3 through its input shaft 4, and is capable of controlling the rotation speed and direction of an internal variable-speed hydraulic pump motor, and controlling a plurality of speed stages. When selecting a speed stage of a mechanical transmission mechanism consisting of Since the signal NE) can be arbitrarily selected within the range from 0 to a certain value, the rotational speed of the output shaft 5 of the transmission 2 can be arbitrarily and steplessly controlled within the range from 0 to a certain value. When the output shaft 5 is forcibly reverse-driven from the outside and rotates at a certain rotation speed, such as when driving with a reduced engine output, adjust the discharge amount of the transmission oil pump. By controlling the speed ratio X, it is possible to reversely control the engine speed. This means that no matter what the vehicle speed is, by controlling the speed ratio X, the degree of engine braking can be arbitrarily selected.

This is performed by controlling the rotation speed and rotation direction of the transmission hydraulic motor and the discharge amount of the transmission hydraulic pump hydraulic oil by the transmission oil pump discharge amount control actuator 6. Selection of each speed stage is performed by a speed stage selection actuator 7. The service brake key 8 is mechanically, hydraulically, or electrically interlocked (not shown) over a wide range of depression amount of the brake lever 9.

The engine brake setting device 21 stores in advance the engine target rotation speed for each position of the brake pedal 9, so when the brake pedal position signal a is input, the engine target rotation speed signal ne and the engine target rotation speed signal 7 are input. and a deviation signal Δne are output to the polarity adding circuit 23. Note that Δne-Ine-N51. Said speed ratio calculation circuit 2
4 is the engine speed signal N. and the vehicle speed signal N. When input, the speed ratio calculation circuit 24 outputs the speed ratio signal X to the speed stage logic circuit 25. X = No/N. Since the width (range) of the speed ratio X value is unique for each speed stage, the speed stage logic circuit 25 determines which speed stage the current speed ratio is in based on the input speed ratio signal A speed stage selection control signal A for selecting a speed stage is output to each speed stage selection actuator 7. The speed stage selection control signal A is also input to the polarity addition (b) path 23. The polarity addition circuit 23 adds positive, negative, or 0 polarity to the deviation signal Δn depending on the state of the speed stage selection control signal A, and outputs the polarized deviation signal Δn to the integrator 26. The integrator 26 integrates the polarized deviation signal Δ"eo and outputs a variable speed oil pump discharge amount control signal to the variable speed oil pump discharge amount control actuator 6. In each speed stage, if (,) (engine speed signal NE) > (engine target speed signal n8), in the direction in which the speed ratio X increases, (b) (engine speed signal NE) < ( In the case of engine target rotation speed signal n, ), the speed ratio X decreases in the direction (C) (engine rotation speed signal N, ) - (engine target rotation speed signal ne), the speed ratio It is added as follows.

(d) When (engine rotation speed signal N,) > (engine target rotation speed signal ne), the transmission hydraulic pump discharge amount control signal is output in the direction of increasing the speed ratio (e) When (engine speed signal N, ) < (engine target speed signal ne), the transmission oil pump discharge amount control signal is output in the direction of decreasing the speed ratio , which acts to increase the engine speed.

(f) In the case of '(engine speed signal N.) - (engine target speed signal n8), the transmission oil pump discharge amount control signal is output so that the speed ratio X maintains its value, and the engine speed acts to keep constant.

Through the processes (d), (e), and (f) above, the actual engine speed converges to the target engine speed, and it becomes possible to arbitrarily select the engine braking force by operating the position of the brake pedal. By the above-described operation, the brake pedal can be operated without being affected by the original service brake. Therefore, in this embodiment, only the engine brake is operated in a range where the amount of depression is small due to the brake pedal alone, and as the amount of depression increases, the service brake is also activated.

The third example shows an example in which the present invention is applied to a hydrostatic-mechanical continuously variable transmission steering system for tracked vehicles having one input shaft and two output shafts.
This will be explained using figures.

FIG. 3 is a block diagram of a hydrostatic-mechanical continuously variable transmission steering system in which a transmission section and a steering section are independent of each other and a service brake is provided in the steering section. In FIG. 3, 33 is an engine, 32 is a hydrostatic-mechanical continuously variable transmission, 34 is an input shaft of the hydrostatic-mechanical continuously variable transmission, and 35 is an output of the hydrostatic-mechanical continuously variable transmission 32. It is the axis. 3
6 is a hydraulic pump discharge amount control actuator for speed change, 37
3 is an actuator for selecting each speed stage, 38 is a steering device, and 3 is a steering device.
9. 40 is a service brake provided on the left and right output shafts, 41 is provided on the output shaft 39, and 42 is provided on the output shaft 40, respectively. 11 is an engine rotation speed detector provided on the input shaft 34. A vehicle speed detector 12 is provided on the output shaft 35 of the hydrostatic-mechanical continuously variable transmission 2. In this hydrostatic-mechanical continuously variable transmission steering system for tracked vehicles, as described above, the transmission section and the steering section are independent of each other, so the operation related to the transmission will be explained as shown in FIG. Since it is the same as that explained with reference to FIG. 2, the explanation will be omitted. Since the effect is the same, it will be omitted. An example in which the present invention is applied to a hydrostatic-mechanical continuously variable transmission steering system in which a transmission section and a steering section are installed in one case and has service brakes on left and right output shaft sections will be described with reference to FIG. FIG. 4 is a block diagram.

In the figure, 55 is a hydrostatic-mechanical continuously variable speed steering device.

Reference numeral 44 indicates the hydrostatic pressure - the input shaft of the mechanical continuously variable speed steering device 55, 48 and 49 indicate the left and right output shafts, respectively, and 46 indicates the hydrostatic pressure - the hydrostatic pressure inside the mechanical continuously variable speed steering device 55.
A mechanical continuously variable transmission section, 47 a steering device section in the hydrostatic-mechanical continuously variable transmission steering device, and 50.51 service brakes provided on the left and right output shafts 48 and 49, respectively. . Reference numeral 52 represents a variable speed hydraulic pump discharge amount control actuator, 53 represents each speed selection actuator, and 54 represents an output shaft of the hydrostatic-mechanical continuously variable transmission section 46. The power of the engine 43 is transmitted through the input shaft 44 of the hydrostatic pressure-mechanical continuously variable transmission steering device 55, and is then transmitted to the hydrostatic pressure-mechanical continuously variable transmission system in the hydrostatic pressure-mechanical continuously variable transmission steering device 55. It has a structure in which the signal is transmitted to the device section 46 and the steering device section 47 to provide the required speed change steering action, and then is transmitted to the left and right output shafts 48 and 49. The engine rotation speed detector 11 is provided on the input shaft 44 of the hydrostatic-mechanical continuously variable transmission steering device 550, and the vehicle speed detector 12 is provided on the output shaft 54 of the hydrostatic-mechanical continuously variable transmission section 46. It's being carried away. In FIG. 4, the arrows on the lines indicate the direction of power transmission, and the ○ marks indicate the combination and branching points of the power.

The service brakes 50, 51 provided on the left and right output shafts 48, 49 and the brake pedal 9 are connected by a conventional mechanical, hydraulic or electrical interlocking mechanism (not shown). The engine rotation speed detector 11 is provided on the input shaft 44 of the hydrostatic-mechanical continuously variable transmission steering device 55, and the vehicle speed detector 12 is provided on the output shaft 54 of the hydrostatic-mechanical continuously variable transmission section 46. However, since these detectors are originally signal detectors for calculating the speed ratio, the key is located in the hydrostatic-mechanical continuously variable speed steering system 55, which is the location where the speed ratio can be calculated. It may be provided at any other suitable location. In the embodiment shown in the block diagram as shown in FIG. 4, the transmission unit and the steering unit are operationally independent, so the action regarding the hydrostatic-mechanical continuously variable transmission unit is the same as the first one. Since it is the same as that explained with reference to FIG. 2, the explanation will be omitted. The effect is also similar.

〔Effect of the invention〕

As described above, the brake device of the present invention is used for a vehicle transmission having a hydrostatic mechanical continuously variable transmission mechanism and a speed change steering device for a tracked vehicle, and has a brake pedal and a brake in a dull position. a detector, an engine brake setting device that stores an engine target rotation speed corresponding to a brake pedal position, an engine rotation speed detector, and an engine rotation speed outputted from the engine brake setting device and the engine rotation speed detector. A speed deviation detector that calculates the absolute value of the deviation from the output, a polarity addition circuit that adds the polarity corresponding to the current vehicle speed to the absolute value of the deviation, and integrates the polarity added to the absolute value of the deviation. The output of the integrator is used as the output of the braking device, and the output is used to increase or decrease the speed ratio via the shift hydraulic pump discharge amount control actuator, thereby changing the actual engine rotation speed to the engine target rotation speed. Since the brake pedal has the function of operating the original service brake, it is possible to operate both the engine brake and the service brake, and for example, the amount of depression of the brake pedal is small. Within this range, it can be set so that only the engine brake operates, and as the amount of depression increases, the service brake can also be set in advance to begin operating.

[Brief explanation of drawings]

FIG. 2 is a block diagram of an embodiment of the present invention, FIG. 1 is a block diagram of an embodiment of the brake device of the present invention, and FIG. 3 is a block diagram of an embodiment of the brake device of the present invention. FIG. 4 is a block diagram of an embodiment of a speed change steering device having a service brake in the device section, in which a speed change device section and a steering device section are installed in one case, and service brakes are provided on the left and right output shafts. FIG. 5 is a block diagram of an embodiment of the variable speed steering device, and is an explanatory diagram of the operation of a conventional brake pedal. 1...Brake device, 2...Continuously variable transmission, 3...
・Engine, 6, 7...actuator, 9...brake. Pedal, 21...Engine brake setting device, 22...
・Speed deviation detector, 23...Polarity adder, 24, 25
゜7... Means for selecting speed stage, 26 river integrator, N
...Engine speed signal, ne...Target engine speed signal corresponding to the amount of brake pedal depression, X...
Speed ratio (No/N, ), x-...Speed ratio (ne/NE
), No,. Vehicle speed detection signal, Δne...deviation, Δ"eo...polarized deviation.

Claims (1)

[Claims] A transmission having a hydraulic-mechanical continuously variable transmission mechanism includes an engine brake setting device that sets a target rotation speed of the engine corresponding to the amount of depression of a brake pedal, and a deviation between a detected value of the engine rotation speed and the target rotation speed. a speed deviation detector for calculating a speed deviation; a means for calculating a speed ratio from a detected value of vehicle speed and a detected value of the engine speed and selecting a speed gear corresponding to the speed ratio; and a means for selecting a speed gear corresponding to the speed ratio; A vehicle brake device comprising: a polarizer that outputs a polarized deviation; and an integrator that integrates the polarized deviation and outputs an operation signal to an actuator.