HYDRAULIC UNIT OF AN ELECTRONICALLY CONTROLLED BRAKING SYSTEM

Abstract

Hydraulic unit of an electronically controlled brake system, comprising a modulator block (80) with several receiving bores (164, 181 to 185) in which several valves (64, 81 to 84) and pressure sensors (85a, 85b) coupled to a master cylinder (20) are installed to control hydraulic brake pressure supplied to vehicle wheels, wherein passages (180) connecting the receiving bores are formed in the modulator block (80) and the passages (180) are formed such that they are divided into two layers (P1, P2), wherein the receiving bores (164, 181 to 185), in which an inlet valve (81), an outlet valve (82), a start valve (83), a simulation valve (64), a pressure sensor (85a, 85b) and a switching valve (84) are installed, are formed in one surface of the modulator block (80) and the receiving bore (186), in which a shut-off valve (86) is installed, is formed in the other surface of the modulator block (80), wherein the multiple receiving bores (164, 181 to 185) formed in a surface of the modulator block (80) have installed the inlet valve (81), the outlet valve (82), the start valve (83), the simulation valve (64), the pressure sensors (85a, 85b) and the switching valve (84) in this order.

Description

BACKGROUND 1. Area

[0001] The present invention relates to a hydraulic unit of an electronically controlled braking system and in particular to a hydraulic unit of an electronically controlled braking system for controlling the brake pressure in a braking system by means of an electronic control. 2. Description of the state of the art

[0002] An electronically controlled braking system for effectively preventing skidding, which may occur during braking of a vehicle, sudden unintentional acceleration, or sudden acceleration, generally includes not only a vehicle braking system booster, a master cylinder, and a wheel cylinder, but also a hydraulic unit for controlling hydraulic brake pressure and an electronic control unit for controlling the hydraulic unit.

[0003] More recently, a system for obtaining greater and more stable braking force has been proposed; for example, an integrated dynamic braking system (IDB system) has been suggested. The proposed IDB system generates stable and high braking force by integrating a master cylinder, a booster, and an electronic stability control (ESC).

[0004] This IDB system comprises a pressure supply device that operates a motor by outputting an electrical signal from a pedal displacement sensor indicating actuation of the brake pedal, thus converting the motor's rotational force into linear motion; and a hydraulic unit with a multi-valve modulator block for controlling a braking operation by receiving hydraulic pressure using a force generated by the pressure supply device. The hydraulic unit includes multiple inlet / outlet valves, a starting valve, a switching valve, a shut-off valve, a pressure sensor, a pedal simulation valve, and similar components to control hydraulic brake pressure, which is transmitted to wheel cylinders located in the vehicle's wheels. These components are compactly integrated within the aluminum modulator block.Several valve bores, an opening to connect the main cylinder to the wheel cylinder, and several passages to guide hydraulic flow in one direction are also incorporated to allow the multiple components to be installed compactly in the modulator block.

[0005] However, since a conventional hydraulic unit has unnecessary dead space in addition to the space in which several components are arranged, an improved component layout is required. Because a larger modulator block is used, the size and weight of the hydraulic unit increase, and thus the problem of rising costs arises.

[0006] Furthermore, a lack of symmetry between two hydraulic circuits formed in the modulator block creates a pressure deviation, resulting in a reduced service life due to the generation of noise and vibrations.

[0007] A hydraulic unit of an electronically controlled braking system according to an embodiment of the present invention can minimize the size of a modulator block by arranging passages formed in the modulator block in two layers, and minimize pressure deviation by producing a structure of two mutually symmetrical hydraulic circuits.

[0008] From DE 10 2006 033 493 A1, a modulator block of a hydraulic unit is known, which has several receiving bores in which several valves and pressure sensors, coupled to a master cylinder to control the hydraulic brake pressure supplied to the vehicle wheels, are installed. Passages connecting the receiving bores are formed in the modulator block, and the passages are formed such that they are divided into two layers. The receiving bores in which an inlet valve, an outlet valve, a starting valve, a simulation valve, a pressure sensor, and a switching valve are installed are formed in one surface of the modulator block, and the receiving bore in which a shut-off valve is installed is formed in the other surface of the modulator block. A similar modulator block is also known from DE 10 2006 059 924 A1. An electronically controlled brake system is also known from DE 10 2013 002 378 A1. OVERVIEW

[0009] It is therefore an aspect of the present invention to provide a hydraulic unit of an electronically controlled braking system according to an embodiment of the present invention, which is capable of minimizing the size of a modulator block by arranging passages formed in the modulator block in two layers and of minimizing pressure deviation by forming a structure of two mutually symmetrical hydraulic circuits. This object is achieved according to the invention by the features of claim 1.

[0010] Additional aspects of the invention are partly described below and partly become apparent from the description, or can be discovered by carrying out the invention.

[0011] According to one aspect of the present invention, a hydraulic unit of an electronically controlled brake system is provided, which includes a modulator block with several receiving bores in which several valves and pressure sensors are installed, which are coupled to a master cylinder for controlling the hydraulic brake pressure supplied to vehicle wheels, wherein the receiving bores are connected passages in the modulator block and the passages are formed such that they are divided into two layers.

[0012] The modulator block can also be designed to have two hydraulic circuits, and the multiple receiving bores and passages forming the two hydraulic circuits can be arranged symmetrically with respect to the center of the modulator block.

[0013] The receiving bores, in which an inlet valve, a drain valve, a start valve, a simulation valve, pressure sensors and a switching valve are installed, can also be formed on one surface of the modulator block, and the receiving bore, in which a shut-off valve is installed, can be installed on the other surface of the modulator block.

[0014] The multiple receiving bores formed on one surface of the modulator block can also accommodate the inlet valve, the outlet valve, the start valve, the simulation valve, the pressure sensors, and the switching valve, in that order.

[0015] The receiving bore in which the shut-off valve is received can also be designed in such a way that it is positioned between the starting valve and the switching valve.

[0016] The modulator block may also have a master cylinder linkage unit, a reservoir linkage unit, a pedal simulator linkage unit, and a pressure supply device linkage unit, which are further formed on the other surface of the modulator block.

[0017] The reservoir connection unit, the pedal simulator connection unit, and the pressure supply device connection unit can also be positioned on a center line of the modulator block that separates the two hydraulic circuits. The reservoir connection unit and the pressure supply device connection unit can be connected to the two hydraulic circuits via the passages.

[0018] A wheel cylinder connection unit can also be formed in a side surface between one surface and the other surface of the modulator block. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] These and / or other aspects of the invention will become apparent and easier to understand with reference to the following description of the exemplary embodiments, which is given in conjunction with the accompanying drawings, of which: Fig. 1 is a diagram of a hydraulic circuit illustrating an electronically controlled braking system according to an embodiment of the present invention; Fig. 2 is a perspective view illustrating a modulator block configured by a hydraulic unit of the electronically controlled braking system according to the embodiment of the present invention; Fig. 3 is a top view showing an upper side of the Fig. 2 modulator blocks shown illustrate; Fig. 4 is a view from below, which is a lower side of the in Fig. 2 modulator blocks shown illustrate this; and Fig. 5 a side cross-sectional view of the in Fig. The 2 modulator blocks shown are shown. DETAILED DESCRIPTION

[0020] Reference will now be made in detail to the embodiments of the present invention illustrated in the accompanying drawings, where identical reference numerals consistently refer to the same elements. Therefore, the present invention is not limited to the drawings described below and may be embodied in various forms, and the drawings described below may be exaggerated to clearly illustrate the spirit of the present invention.

[0021] Fig. Figure 1 is a diagram of a hydraulic circuit illustrating an electronically controlled braking system according to an embodiment of the present invention.

[0022] According to the drawing, the electronically controlled braking system according to the present invention comprises: a master cylinder 20 for generating hydraulic pressure; a reservoir 30 coupled to an upper part of the master cylinder 20 for storing oil; wheel cylinders 40, each installed on vehicle wheels RR, RL, FR and FL, to brake using the transmitted hydraulic pressure; a hydraulic pressure supply device 50, which is mechanically actuated by receiving a driver's braking intention as an electrical signal from a pedal displacement sensor 11, which detects a displacement of a brake pedal 10; a hydraulic unit 70 for controlling the hydraulic pressure to brake the vehicle wheels with a force generated by the hydraulic pressure supply device 50; and a pedal simulator 60, which is connected to the master cylinder 20 to provide a response force for the brake pedal 10.

[0023] The master cylinder 20 can consist of at least one chamber to generate hydraulic pressure, but as shown, it is equipped with two hydraulic pressure units 20a and 20b. Since the master cylinder 20 has these two hydraulic pressure units 20a and 20b, it can ensure safety by actuating the other hydraulic pressure unit if one of the hydraulic pressure units fails.

[0024] The hydraulic pressure supply device 50 comprises a cylinder 51 with a predetermined space for receiving and storing oil; and a ball screw component 54 for exerting pressure on a piston 52 located in the cylinder 51 by converting a rotary force from a motor 55 into a linear motion. That is, the motor 55 generates the rotary force through the signal detected by the pedal displacement sensor 11, and the ball screw component 54 converts the rotary motion into a linear motion to exert pressure on the piston 52, thus generating hydraulic brake pressure. The ball screw component 54, which is a device for converting the rotary force into linear motion, is a known technology, so a detailed description is omitted.

[0025] An unillustrated reference number “85a” is a first pressure sensor for detecting the hydraulic pressure of a cylinder 51, and a reference number “85b” is a second pressure sensor for measuring the oil pressure of the master cylinder 20.

[0026] The pedal simulator 60 is connected to the master cylinder 20 to provide a reaction force in accordance with the pedal pressure exerted on the brake pedal 10. The pedal simulator 60 comprises: a simulation chamber 61, designed to store the oil dispensed by the master cylinder 20; a reaction piston 62 located within the simulation chamber 61; a reaction spring 63 for elastically supporting the reaction piston 62; and a simulation valve 64, connected to a rear end of the simulation chamber. The simulation valve 64 is installed in a modulator block 80 of the hydraulic unit 70, which will be described below, and its structure will be described again below.

[0027] According to the present invention, the hydraulic unit 70 includes the modulator block 80 with a hydraulic circuit that controls the transmission of the hydraulic brake pressure to the wheel cylinders 40, which are installed in vehicle wheels FL, FR, RL and RR respectively.

[0028] The hydraulic circuit comprises a first hydraulic circuit 70A for controlling the transmission of hydraulic pressure by connecting the hydraulic pressure unit 20a, one of the pair of hydraulic pressure units 20a and 20b of the main cylinder 20, to the wheel cylinders 40 located on two vehicle wheels FR and RL; and a second hydraulic pressure unit 20b for controlling the transmission of hydraulic pressure by connecting the other hydraulic pressure unit 20b to the wheel cylinders 40 located on the other vehicle wheels FL and RR. The first and second hydraulic circuits 70A and 70B are compactly installed in the modulator block 80.

[0029] Each of the hydraulic circuits 70A and 70B for controlling the hydraulic pressure transmitted to each of the vehicle wheels FL, FR, RL and RR contains passages 180 formed in the modulator block 80 and connected to the master cylinder 20, reservoir 30, wheel cylinders 40, hydraulic pressure supply device 50 and pedal simulator 60; and several valves 64, 81, 82, 83, 84 and 86 and the pressure sensors 85a and 85b installed in the modulator block 80 to be connected to the passages 180.

[0030] More precisely, the multiple valves 64, 81, 82, 83, 84 and 86 include: inlet valves 81, arranged as a normally open solenoid valve (hereinafter referred to as "NO type") on the upper sides of the wheel cylinders 40 to control the transmission of hydraulic pressure to the wheel cylinders 40; outlet valves 82, arranged as a normally closed solenoid (hereinafter referred to as "NC type") on the lower sides of the wheel cylinders 40 to control the output of hydraulic pressure from the wheel cylinders 40; switching valves 84 and shut-off valves 86, each provided in the passages 180 connecting the hydraulic pressure supply device 50 with the hydraulic circuits 70A and 70B, to control the hydraulic pressure transmitted to the wheel cylinder 40 by an opening and closing operation;A pair of starting valves 83, provided in the passages 180 of the hydraulic circuits 70A and 70B between the master cylinder 20 and the wheel cylinders 40, which control the hydraulic pressure transmitted to the wheel cylinders 40 by an opening and closing process; and a simulation valve 64, provided in the passage 180 connecting the simulation chamber 61 and the reservoir 30. The pressure sensor 85b for measuring the oil pressure of the master cylinder 20 can be provided between the starting valve 83 and the master cylinder 20. Therefore, when braking is applied by a driver, the passages are blocked by the starting valves 83, and the braking intention requested by the driver can be determined by the pressure sensor 85b.

[0031] The switching valve 84 can be configured as a normally open (NO) type solenoid valve, which is closed in its normal state and opens when an opening signal is received. The starting valve 83 can be configured as a normally closed (NC) type solenoid valve, which is open in its normal state and closes when a closing signal is received from an electronic control unit (not shown).

[0032] The shut-off valves 86 are installed in the passages connecting the pressure chamber of the cylinder 51 of the hydraulic pressure supply device 50 with the hydraulic circuits 70A and 70B, and they are each installed in parallel with the pair of switching valves 84. The shut-off valve 86, which is configured as a unidirectional shut-off valve to transmit hydraulic pressure only to the wheel cylinder 40, prevents a pressure increase due to an actuation delay of the switching valve 84.

[0033] The opening and closing processes of valves 64, 81, 82, 83, 84 and 86 are controlled by the electronic control unit.

[0034] The hydraulic unit 70 has the passages 180 formed in and passing through the modulator block 80 to connect the master cylinder 20, reservoir 30, wheel cylinder 40, hydraulic pressure supply device 50 and pedal simulator 60, and has the valves 64, 81, 82, 83, 84 and 86 compactly installed to control the hydraulic brake pressure through the passages 180.

[0035] Next, the hydraulic unit 70 provided in the electronically controlled braking system will be described in detail with reference to the Fig. 2, Fig. 3, Fig. 4 to Fig. 5 described. That is, according to one aspect of the present invention, an arrangement structure of several receiving bores in which the several valves 64, 81, 82, 83, 84 and 86 and the pressure sensors 85a and 85b of the modulator block 80 are installed, and the passages 180 for connecting the several receiving bores are described.

[0036] Fig. Figure 2 is a perspective view illustrating a modulator block configured by a hydraulic unit of the electronically controlled braking system according to the embodiment of the present invention. Fig. 3 is a top view showing an upper side of the Fig. The 2 modulator blocks shown illustrate this. Fig. 4 is a view from below, showing the lower side of the in Fig. The 2 modulator blocks shown are illustrated, and Fig. 5 is a side cross-sectional view of the in Fig. 2 modulator blocks shown.

[0037] An upper surface F1, a lower surface F2 and a side surface F3 for providing a direction for the modulator block 80 are defined with reference to the one in Fig. The modulator block 80 shown in Figure 2 is provided to facilitate understanding of the invention, which is not limited to this. It should be noted that the surface can be modified to provide a direction for the modulator block depending on the position in which the modulator block 80 is installed.

[0038] According to the Fig. 2, Fig. 3, Fig. 4 to Fig. The modulator block 80 has a six-sided shape. The modulator block 80 contains several receiving bores 164, 181, 182, 183, 184, 185 and 186, in which the several valves 64, 81, 82, 83, 84 and 86 and the pressure sensors 85a and 85b are installed, and the passages 180 as connections between the receiving bores 164, 181, 182, 183, 184, 185 and 186. That is, the modulator block 80 contains the receiving bores 164, 181, 182, 183, 184, 185 and 186 and the passages 180, which are formed on opposite sides with reference to a center line C, to configure two hydraulic circuits 70A and 70B.

[0039] More precisely, the receiving bores 164, 181, 182, 183, 184, and 185, in which the inlet valve 81, the outlet valve 82, the start valve 83, the simulation valve 64, the pressure sensors 85a and 85b, and the switching valve 84 are installed, are formed on one surface of the modulator block 80, that is, the upper surface F1. The receiving bore 186, in which the shut-off valve 86 is installed, is formed on the other surface of the modulator block 80, that is, the lower surface F2. The passages 180 connecting the receiving bores 164, 181, 182, 183, 184, 185, and 186 are also formed in the modulator block 80. As shown in Fig. As shown in Figure 5, the passages 180 are formed in such a way that they are divided into two layers P1 and P2.

[0040] The inlet valve 81, the outlet valve 82, the start valve 83, the simulation valve 64, the pressure sensors 85a and 85b and the switching valve 84 are installed in the receiving bores 164, 181, 182, 183, 184 and 185, which are formed in the upper surface F1 of the modulator block 80, in this order. As shown, several first receiving bores 181 of a first valve row L1, in which the several inlet valves 81 are installed, several second receiving bores 182 of a second valve row L2, in which several outlet valves 82 are installed, several third receiving bores 183 of a third valve row L3, in which the several start valves 83 are installed, and several fourth receiving bores 184 of a fourth valve row L4, in which the several switching valves 84 are installed, are formed in the upper surface F1 of the modulator block 80.The receiving bore 164, in which the simulation valve 64 is installed, is formed between the third receiving bores 183 in the third valve row L3. That is, the receiving bore 164, in which the simulation valve 64 is installed, is formed such that it is positioned on the centerline C of the modulator block 80. The receiving bores 164, 181, 182, 183, and 184, which are formed in the first to fourth valve rows L1 to L4, are arranged in the upper surface F1 of the modulator block 80 in a transverse direction perpendicular to the centerline C.

[0041] Several receiving bores 185, in which the pressure sensors 85a and 85b are installed, are also formed in the upper surface F1 of the modulator block 80 between the third valve row L3 and the fourth valve row L4 in the transverse direction.

[0042] Furthermore, in the lower surface F2 of the modulator block 80, the multiple receiving bores 186, in which the multiple shut-off valves 86 are installed, are formed transversely between the third valve row L3 and the fourth valve row L4. The receiving bores 185, in which the pressure sensors 85a and 85b are installed, and the receiving bores 186, in which the shut-off valves 86 are installed, are positioned alternately to maximize the utilization of the internal space of the modulator block 80.

[0043] A master cylinder connection unit 120, a reservoir connection unit 130, a pedal simulator connection unit 160, and a pressure supply device connection unit 150 are formed in the lower surface F2 of the modulator block 80. That is, the master cylinder connection unit 120 is connected to the master cylinder 20. The reservoir connection unit 130 is connected to the reservoir 30. The pedal simulator connection unit 160 is connected to the pedal simulator 60. The pressure supply device connection unit 150 is connected to the hydraulic pressure supply device 50. The reservoir connection unit 130, the pedal simulator connection unit 160, and the pressure supply device connection unit 150 are formed on the center line C of the modulator block 80, which separates the two hydraulic circuits 70A and 70B.The tank connection unit 130 and the pressure supply device connection unit 150 are connected to the hydraulic circuits 70A and 70B via the passages 180. The pedal simulator connection unit 160 is also formed on a lower side of the receiving bore 164, in which the simulation valve 64, formed in the upper surface F1 of the modulator block 80, is installed, and the master cylinder connection unit 120 is formed on a lower side of the receiving bore 183, in which the starting valve 83 is installed.

[0044] A wheel cylinder connection unit 140 is formed in a side surface between the upper surface F1 and the lower surface F2 of the modulator block 80. It is preferred that the wheel cylinder connection unit 140 is formed in the side surface F3 of the modulator block 80 adjacent to the inlet valve receiving bore 181 in order to easily control the hydraulic brake pressure flowing along the passages 180.

[0045] As described above, the receiving bores 164, 181, 182, 183, 184, 185, and 186 and the passages 180 formed in the modulator block 80 are arranged such that they are laterally symmetrical with respect to the centerline C of the modulator block 80. Therefore, a pressure differential between the two hydraulic circuits 70A and 70B can be minimized. Furthermore, the passages 180 connected to the receiving bores 164, 181, 182, 183, 184, 185, and 186 are arranged as shown in Fig. 5 is shown, arranged in two layers P1 and P2, thereby minimizing the cost of manufacturing the modulator block 80 and reducing the size and weight of the modulator block 80.

[0046] The hydraulic unit of the electronically controlled braking system according to an embodiment of the present invention can simplify a structure compared with the conventional one by arranging the passages 180 formed in a modulator block 80 in two layers, and it can also reduce the weight and cost by minimizing the size of the modulator block 80.

[0047] The two hydraulic circuits, which are configured from the multiple valves 64, 81, 82, 83, 84 and 86 and the passages 180 installed in the modulator block 80, are also formed symmetrically to each other, thereby minimizing a pressure deviation between the hydraulic circuits 70A and 70B.

[0048] Furthermore, the multiple valves 64, 81, 82, 83, 84 and 86 for controlling the flow of the hydraulic brake pressure are compactly installed in the modulator block 80 by improving the installation position of the valves 64, 81, 82, 83, 84 and 86, thereby utilizing a larger size of the modulator block 80.

Claims

[1] Hydraulic unit of an electronically controlled brake system, comprising a modulator block (80) with multiple receiving bores (164, 181 to 185) in which multiple valves (64, 81 to 84) and pressure sensors (85a, 85b) coupled to a master cylinder (20) are installed to control hydraulic brake pressure supplied to vehicle wheels, wherein passages (180) connecting the receiving bores are formed in the modulator block (80) and the passages (180) are formed such that they are divided into two layers (P1, P2), wherein the receiving bores (164, 181 to 185), in which an inlet valve (81), a drain valve (82), a start valve (83), a simulation valve (64), a pressure sensor (85a, 85b) and a switching valve (84) are installed, are formed in one surface of the modulator block (80) and the receiving bore (186), in which a shut-off valve (86) is installed, is formed in the other surface of the modulator block (80), wherein the multiple receiving bores (164, 181 to 185) formed in a surface of the modulator block (80) have installed the inlet valve (81), the outlet valve (82), the start valve (83), the simulation valve (64), the pressure sensors (85a, 85b) and the switching valve (84) in this order. [2] Hydraulic unit according to claim 1, wherein the modulator block (80) is formed such that it has two hydraulic circuits (70A, 70B), and the multiple receiving bores (164, 181 to 185) and the passages (180) forming the two hydraulic circuits (70A, 70B) are formed laterally symmetrical with respect to the center of the modulator block (80). [3] Hydraulic unit according to one of claims 1 or 2, wherein the receiving bore (186) in which the shut-off valve (86) is received is formed such that it is positioned between the starting valve (83) and the switching valve (84). [4] Hydraulic unit according to any one of claims 1 to 3, wherein the modulator block (80) has a master cylinder connection unit (120), a reservoir connection unit (130), a pedal simulator connection unit (160) and a pressure supply device connection unit (150) which is further formed in the other surface of the modulator block (80). [5] Hydraulic unit according to claim 4, wherein the reservoir connection unit (130), the pedal simulator connection unit (160) and the pressure supply device connection unit (150) are positioned on a center line of the modulator block (80) which separates the two hydraulic circuits (70A, 70B) and where the container connection unit (130) and the pressure supply device connection unit (150) are connected through the passages (180) to the two hydraulic circuits (70A, 70B). [6] Hydraulic unit according to any one of claims 1 to 5, wherein a wheel cylinder connection unit (140) is formed in a side surface between one surface and the other surface of the modulator block (80).

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