JPS6296161A - Solenoid servo brake device of automobile - Google Patents

Abstract

PURPOSE:To make a solenoid small-sized and prevent the rise lag of a solenoid suction force by effectively utilizing only advantages of the series type and parallel type devices. CONSTITUTION:Two assist cylinder assemblies 10, 20 for front and rear wheels are arranged separately from a master cylinder 3. Both assemblies 10, 20 have assist pistons 11, 21 slidably arranged in assist cylinders 14, 24. Assist pins 11, 21 divide cylinder changers 15, 16, 25, 26. Assist pistons 11, 21 are connected to plungers 13, 23 via connecting rods 12, 22. These plungers 13, 23 are sucked to the left by the excitation of solenoids 17, 27 fitted to assist cylinders in parallel.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to an electromagnetic servo brake device that utilizes electromagnetic force to obtain assist force.

(Prior art) Automobile brakes are often equipped with a booster that adds an assist force to the brake pedal depression force, but in the past, most of these devices used the engine's intake negative pressure. . However, since it is difficult to adjust the intake negative pressure, it is difficult to perform detailed control such as increasing or decreasing the braking nozzle depending on the amount of depression of the brake pedal, and if the engine stops, assist force cannot be obtained, and electric vehicles However, there is a problem that negative intake pressure cannot be obtained.

For this reason, an electromagnetic servo brake device has been proposed in which assist force is obtained by electromagnetic force instead of engine intake negative pressure. For example, as proposed by the applicant,
As in the device disclosed in No. 118559, an assist cylinder assembly is provided in communication with a mask cylinder, and an electromagnetic means for generating assist hydraulic pressure is provided therein,
There is a system in which the assist hydraulic pressure is used as an auxiliary force for the piston pushing force of the mask cylinder, so that a desired assist force can be obtained in accordance with the force with which the driver depresses the brake pedal.

Such conventional electromagnetic servo brake devices can be roughly divided into the series type shown in Figure 2 and the parallel type shown in Figure 3 based on their configuration.The structure, operation, etc. of both types are different. It is described below.

First, the series method shown in FIG. 2 will be explained.

The other end of the operating rod 52, one end of which is connected to the brake pedal 51, is connected to the inside of the mask cylinder 53 (8).
A movable primary piston 52a is fixedly installed, and when the brake pedal 51 is stepped on, this primary piston 52
a is pushed in, and the hydraulic oil in the mask cylinder 53 is compressed. The hydraulic chamber of the mask cylinder 53 is connected to the front and rear hydraulic chambers 53a and 53b by the secondary piston 54.
Each hydraulic chamber 53a, 53b communicates with the brake cylinders of the front and rear wheels via hydraulic lines 57 and 58. For this reason, the brake pedal 51
is depressed and compressed by the primary piston 52a, resulting in hydraulic pressure in the pressure chambers 53a and 53b on both sides, which is sent to the brake actuation cylinder to actuate the brake. On the other hand, a plunger 55 is attached to the operating rod 52 and receives a suction force to the left in the figure when a solenoid 56 is excited.
5 is attracted to the left, and the compression force of the primary piston 52a is assisted by the depression force of the brake pedal 51.

Note that the controller 60 receives signals from a pushing force sensor 61 that detects the pushing force of the operating rod 52 and a hydraulic sensor 62 that detects the hydraulic pressure in the hydraulic line 62, and adjusts the appropriate assist force according to the pedal force. Excitation control of the solenoid 56 is performed so as to add .

When such a series type electromagnetic servo brake is used, the number of required parts is relatively small and the structure is relatively simple.Also, when the solenoid 56 is energized, there is a delay in the rise of the suction force. Since the operating rod 52 and the plunger 55 are connected, there is no delay in the movement of the branch 1755 due to this start-up delay, which has the advantage of not being affected by the start-up delay. However, the hydraulic line 57°58
When hydraulic pressure failure occurs in either the front or rear hydraulic chambers 53a, 53b due to damage to the wheel brake cylinder, damage to the wheel brake cylinder, etc., there is a problem that assist force cannot be obtained because there is no margin in the stroke of the plunger 55. be. For this reason, even if one side oil pressure failure occurs, the assist force is 1! ? Although it is possible to lengthen the stroke of the plunger 55 so that the solenoid 56 is larger, there is a problem in that the solenoid 56 becomes larger and layout constraints are increased in order to arrange it integrally with the mask cylinder 53.

Next, the parallel method shown in FIG. 3 will be explained. A primary piston 52a is fixed to the other end of the operating rod 72, one end of which is connected to the brake pedal 71, and a primary piston 74 inside the mask cylinder 73.
The left side part is divided into front and rear hydraulic chambers 73a and 73b by a secondary piston 74, and both side pressure chambers 73
Similarly to the series system shown in FIG. 2, a and 73b communicate with the brake cylinders of the front and rear wheels via hydraulic lines 83 and 84, respectively. However, in the case of the parallel system, an assist hydraulic chamber 73c is formed on the right side of the primary piston 74, and this assist hydraulic chamber 73c is formed on the right side of the primary piston 74.
3C communicates with a cylinder chamber 76a of an assist cylinder 76 via a hydraulic line 75. This cylinder W76a is installed in the interior of the assist cylinder 76 with assist screws 1 to 1.
assist screws 1 to 77a.
The plunger 77a is connected to a plunger 78 via a rod 77. Therefore, when the solenoid 79 is excited and the plunger 78 is attracted to the left, the assist piston 77
a compresses the hydraulic oil in the cylinder 6a to generate assist hydraulic pressure, and this assist hydraulic pressure acts on the assist 1 hydraulic chamber 73c via the hydraulic line 75 to assist the pushing force of the primary piston 72a. It has become.

Note that the pressing force sensor 82. As in the case of FIG. 2, the excitation control of the solenoid 79 is performed by the controller 80 based on the detection by the oil pressure sensor 81.

When such a parallel type electromagnetic servo brake is used, the solenoid can be placed separate from the mask cylinder, which has the advantage of greater flexibility in layout of the solenoid, and also prevents one-sided hydraulic pressure failure. It has the advantage that it is easy to change the assist force even when the solenoid is energized. There is a delay in the movement of the plunger 78 due to a delay in the rise of the solenoid suction force at
There is a problem in that a misalignment occurs in the movements of the operating rod 72 and the plunger 78, and the suction force margin against the load decreases.

(Object of the Invention) In view of the advantages and disadvantages of the above-mentioned series type and parallel type devices, it is an object of the present invention to provide an electromagnetic nervo brake device that improves the disadvantages while retaining the advantages of both types. be.

(Structure of the Invention) The electromagnetic servo brake device of the present invention is provided with a slidable assist piston in each cylinder, and the assist piston divides the assist cylinder chamber into a front hydraulic chamber and a rear hydraulic chamber. Then, electromagnetic force is applied to the plunger connected to the assist piston using electromagnetic means to press the assist piston, generating hydraulic pressure in the front hydraulic chamber in accordance with the electromagnetic force, and furthermore, the rear hydraulic chamber is controlled by the brake pedal depression force. The front hydraulic chamber is connected to a cylinder for operating the wheel brake, and the assist piston is pushed in the rear hydraulic chamber in response to the hydraulic pressure from the master cylinder. The present invention is characterized in that the hydraulic pressure in the front hydraulic chamber, which is generated in response to the force and the assist piston depression due to the electromagnetic force applied to the plunger, is applied to the cylinder for operating the wheel brake.

(Example) A preferred example of the present invention will be described below with reference to FIG.

One end is connected to the brake pedal 1 and the brake pedal 1 is connected to the brake pedal 1.
A primary piston 2a is fixed to the (I!! end of the operating rod 2, which is moved left and right in the figure in response to the operation of the operating rod 2.The primary piston 2a is slidably inserted into the mask cylinder 3, and the cylinder define a room,
This cylinder chamber is divided into two by a secondary piston 4 slidably inserted into the mask cylinder 3 into a first oil pressure chamber 3a and a second oil pressure chamber 3b.

On the other hand, two assist cylinder assemblies 10, 20 for the front J5 and the brake wheel are arranged separately from the mask cylinder 3. Both assemblies 10.20 have the same structure, and an assist piston 11.21 is slidably disposed in the assist cylinder 14.24, and as shown, this assist piston 11.2 is connected to the assist cylinder 14.2. ．．
The 2/I cylinder chamber is divided into two parts and the front hydraulic heater is 15.25 mm.
and a rear hydraulic chamber 16.26. The assist piston 11.21 is connected via a connecting rod 12, 22 to a plunger 13.23. This plunge 1713.23 is attracted to the left in the figure by the excitation of solenoids 17 and 27 attached side by side to the assist cylinder 14°24, and this suction force causes the assist piston 11.21 to move to the left. The hydraulic oil in the front hydraulic chambers 15 and 25 is filled with oil F according to the suction force.
[ occurs.

The first hydraulic pressure to 3a in the mask cylinder 3 communicates with the rear hydraulic chamber 26 of the assist cylinder assembly 20 via the hydraulic line 6, and the second hydraulic pressure to 3a in the mask cylinder 3 communicates with the rear hydraulic chamber 26 of the assist cylinder assembly 20.
1 pressure to 3b communicates with the rear turn ff to 76 of the cylinder assembly 10 to the assist 1 via the hydraulic line 5.

In the brake device having the above configuration, the brake pedal 1
When the pedal is stepped on, the hydraulic pressure corresponding to the pedal depression force generated in the first and second hydraulic chambers 3a and 3b acts on the rear hydraulic chamber 16.26 via the hydraulic lines 5 and 6, and the assist piston 1
1.21 to generate a predetermined hydraulic pressure in the hydraulic oil in the front hydraulic chamber 15.25 corresponding to the pedal depression force. The hydraulic pressure in this front hydraulic chamber 15.25 acts on the brake cylinder of each wheel via a hydraulic line 18.28 to effect brake operation. In this case, a pushing force sensor 31 is attached to the operating rod 2 to detect the force applied to the rod 2 when the brake pedal 1 is stepped on, and the front hydraulic chamber 1
Hydraulic pressure sensors 32.33 for detecting this oil pressure are attached to the hydraulic lines 18.28 that communicate from 5.25 to the brake cylinders of each wheel, and detection signals from these pressure sensors 31 and oil pressure sensors 32.33 are is input to the controller 30. Therefore, when the brake pedal 1 is stepped on and a detection signal from the push force sensor 31 is input, the controller 30 sends a signal to the solenoid 17, 27.
Send an activation signal to energize the plunger 13.2.
3. Apply suction force to the left in the figure. Plunger 17.2
When a suction force is applied to the engine 7, the oil pressure in the front hydraulic chamber 15.25 increases in response to this suction force, and the braking force increases. In other words, the brake assist force is removed by excitation of the solenoid 17.27.The hydraulic pressure at this time is detected by the hydraulic pressure sensor 32.33, and the solenoid 17.27 responds to the pushing force acting on the operating rod 2.
controller 30 so that the assist force of
The energization of solenoid 17.2.7 is controlled by
Fine-grained control is now possible.

With this configuration, two specific pesoslenoids are required in the conventional series or parallel system, but the required excitation force per solenoid is half, so the solenoids 17 and 27 can be made smaller. Therefore, the assist cylinder assembly 10.20 can be made smaller. Furthermore, this assist cylinder assembly 10.
20 can be connected to the mask cylinder and the brake cylinder of each wheel by hydraulic piping, so it can be installed anywhere as long as the hydraulic piping is installed, and there is a great degree of freedom in the position of installation, making it easy to arrange the layout on the vehicle. has a large degree of freedom. Furthermore, when the brake pedal 1 is depressed, the hydraulic pressure in the mask cylinder acts on the rear hydraulic pressure v16, 26 of the assist cylinder assembly 10.20, and also on the plunger 13.23 via the assist piston 11.21 and the connecting rod 12.22. Since it is designed to be moved, it is affected by the start-up delay of the solenoid suction force.
There's nothing wrong with that.

Further, even if a failure occurs in the hydraulic system on one side, for example, if the hydraulic line 28 is damaged, the assist cylinder assembly 10 on the other side operates without being affected by the oil pressure failure.

(Effects of the Invention) As explained above, according to the present invention, the assist piston divides the assist cylinder into two parts, the front cylinder and the rear cylinder, and communicates the front hydraulic chamber with the cylinder for operating the wheel brake, while also communicating the rear hydraulic chamber with the cylinder for operating the wheel brake. The chamber is communicated with the mask cylinder, and electromagnetic means applies a pressing force to the assist piston to increase the hydraulic pressure in the front hydraulic chamber to assist the brake horn, so the assist cylinder assembly is separated from the mask cylinder. There is a high degree of freedom in layout. In addition, there is no delay in the start of the plunger's movement due to a delay in the rise of the suction force of the solenoid, so the responsiveness of the brake operation is good.

[Brief explanation of drawings]

FIG. 1 is a schematic diagram showing an example of an electromagnetic servo brake device according to the present invention, FIGS. 2 and 3 are schematic diagrams showing a conventional electromagnetic servo brake device, and FIG. 2 shows a series type device. FIG. 3 is a diagram showing a parallel type device. 1...Brake pedal 3...Mask cylinder 5
．． 6.28...Hydraulic line 10.20...Assist cylinder assembly 11.2
1...Assist piston 13.23...Plunger 14.24...Assist cylinder 17.27...Solenoid 30...Controller Fig. 1

Claims (1)

[Scope of Claims] A master cylinder that receives a brake pedal depression force and generates hydraulic pressure corresponding to the depression force; an assist cylinder; and an assist piston slidably disposed within the assist cylinder; A front hydraulic chamber in which the cylinder chamber of the assist cylinder communicates with a cylinder for operating the wheel brake;
An electromagnetic force is applied to an assist cylinder assembly divided into two into a rear hydraulic chamber communicating with the master cylinder and a plunger connected to the assist piston to press the assist piston, and the electromagnetic force is applied to the front hydraulic chamber. An electromagnetic servo brake device for an automobile, comprising an electromagnetic means that generates hydraulic pressure according to the amount of pressure.