Vehicle control device

Abstract

To improve a theft prevention effect by discouraging a thief from stealing a vehicle while making execution of theft prevention control hard to be noticed by the thief.SOLUTION: A vehicle control device which is mounted on a vehicle having a brake mechanism comprises one or a plurality of processors and one or a plurality of storage media storing a program executed with the one or the plurality of processors. The program includes one or a plurality of commands. The command causes the one or the plurality of processors to execute brake control processing to release a stroke applied on a brake pedal with a brake booster with the brake mechanism subject to brake fluid pressure through keeping a first valve arranged in a brake fluid circuit in a closed state after the brake mechanism is subject to the brake fluid pressure with a certain amount of stroke or more applied to the brake pedal with the brake booster in response to input of a predetermined signal corresponding to detection of a vehicle theft.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a vehicle control device that controls a vehicle having a braking mechanism, and particularly to a technique for preventing vehicle theft.

Background Art

[0002] The following Patent Document 1 discloses a technique for applying brakes to stop a vehicle when it is determined that the vehicle is in a stolen state.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] Here, setting the vehicle in a brake hold state in response to the detection of vehicle theft is effective in preventing a thief from stealing the vehicle, but it may lead to the thief noticing that the anti-theft control has been activated.

[0005] The present invention has been made in view of the above circumstances, and aims to make it difficult for a thief to notice that the anti-theft control has been activated, and to reduce the thief's desire to steal the vehicle, thereby improving the anti-theft effect.

Means for Solving the Problems

[0006] The vehicle control device according to the present invention is a vehicle control device in a vehicle having a braking mechanism, comprising one or more processors and one or more storage media storing a program executed by the one or more processors. The program includes one or more instructions which cause the one or more processors to execute a braking control process of, in response to the input of a predetermined signal corresponding to the detection of vehicle theft, stroking a brake pedal by a brake booster by a certain amount or more to apply brake hydraulic pressure to the braking mechanism and then maintaining a first valve arranged in a brake hydraulic pressure circuit in a closed state to maintain the hydraulic pressure application state to the braking mechanism while releasing the stroke of the brake pedal by the brake booster. As a result, in response to the detection of vehicle theft, the vehicle enters a brake hold state and the reaction force to the stepping force of the brake pedal is reduced (the brake pedal becomes loose and rattling).

Advantages of the Invention

[0007] According to the present invention, it is possible to make it difficult for a thief to notice that anti-theft control has been activated, reduce the thief's desire to steal the vehicle, and improve the anti-theft effect.

Brief Description of the Drawings

[0008]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9

Mode for Carrying Out the Invention

[0009] <1. Device Configuration> Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. FIG. 1 is a block diagram showing a configuration overview of a vehicle control device 10 as an embodiment. The vehicle control device 10 is provided inside the vehicle 1. In the present embodiment, the vehicle 1 is configured as, for example, a four-wheel automobile and an engine vehicle having an engine as a drive source for the wheels. Hereinafter, regarding the four wheels of the vehicle 1, the front wheels are denoted as wheels 2, and the rear wheels are denoted as wheels 3. When distinguishing between the left and right wheels, the right front wheel is denoted as wheel 2R, the left front wheel is denoted as wheel 2L, the right rear wheel is denoted as wheel 3R, and the left rear wheel is denoted as wheel 3L.

[0010] Although not shown in FIG. 1, the vehicle 1 has a brake mechanism 20 for each wheel. The configuration of the brake mechanism 20 of the vehicle 1 and the hydraulic circuit 30 for driving the brake mechanism 20 will be described later.

[0011] As shown in the figure, the vehicle control device 10 includes a key system control unit 11, an engine control unit 12, a brake control unit 13, an anti-theft determination unit 14, a communication unit 15, an engine-related actuator 16, a brake-related actuator 17, sensors 18, a bus 19, a hydraulic circuit 30, and a brake booster 41.

[0012] The key system control unit 11, the engine control unit 12, the brake control unit 13, and the theft determination unit 14 are provided with a processor such as a CPU (Central Processing Unit), and storage media as a ROM (Read Only Memory) and a RAM (Random Access Memory). In each ROM, the operation programs of the key system control unit 11, the engine control unit 12, the brake control unit 13, and the theft determination unit 14 are stored, and in each RAM, the operation programs stored in the ROM are expanded. Also, each RAM is also used for temporarily storing data used by the key system control unit 11, the engine control unit 12, the brake control unit 13, and the theft determination unit 14 for processing. The key system control unit 11, the engine control unit 12, the brake control unit 13, and the theft determination unit 14 are connected via a bus 19 corresponding to, for example, CAN (Controller Area Network) communication, and are enabled to perform data communication with each other.

[0013] The sensors 18 comprehensively indicate various sensors provided in the vehicle 1. The sensors included in the sensors 18 include, for example, an engine speed sensor 18a that detects the rotational speed of the engine, an accelerator opening sensor 18b that detects the depression amount of the accelerator pedal as an accelerator operation amount, a brake stroke sensor 18c that detects the depression amount of the brake pedal 25 provided in the vehicle 1 as a stroke amount, and the like. Also, the sensors included in the sensors 18 include a wheel speed sensor 18d that detects the rotational speed of the wheels, a motion sensor 18e that detects the movement of the vehicle 1, such as an acceleration sensor or an angular velocity sensor, a human presence sensor 18f that detects the movement of a person inside or outside the vehicle by irradiating ultrasonic waves or lasers, and a camera 18g that images the inside or outside of the vehicle, and the like.

[0014] The communication unit 15 communicates with a portable terminal device that receives an input operation for locking and unlocking the door lock of the vehicle 1, such as a smart key. In this example, the identification information of the portable terminal device is stored in the portable terminal device.

[0015] The key system control unit 11 collates the identification information received by the communication unit 15 from the portable terminal device with the pre-registered identification information, and performs a determination process as to whether the identification information of each other matches as an authentication process. When there is a request to unlock the door lock, the key system control unit 11 unlocks the door lock if the authentication by the above authentication process is successful. Further, the key system control unit 11 supplies an engine start permission signal to the engine control unit 12 on the condition that the authentication is successful.

[0016] Furthermore, when the key system control unit 11 detects that the above authentication process has been performed illegally due to rewriting of the registered identification information or the like, it supplies an illegal detection signal indicating that fact to the theft determination unit 14.

[0017] The engine control unit 12 controls various actuators provided as the engine-related actuators 16 based on detection signals from predetermined sensors in the sensors 18, operation input information by an operator, and the like. As the engine-related actuators 16, various actuators related to engine drive, such as a throttle actuator that drives a throttle valve and an injector that performs fuel injection, are provided.

[0018] For example, the engine control unit 12 performs start / stop control of the engine according to an operation of an ignition switch or the like. At this time, the engine control unit 12 performs start control of the engine on the condition that an engine start permission signal is input from the key system control unit 11. Further, the engine control unit 12 also controls fuel injection timing, fuel injection pulse width, throttle opening, etc. based on detection signals from an engine speed sensor 18a, an accelerator opening sensor 18b, and the like.

[0019] Based on the detection signals from predetermined sensors in the sensors 18 and the operation input information by the operator, etc., the brake control unit 13 controls various actuators provided as the brake-related actuators 17 and the brake booster 41. Examples of the brake-related actuators 17 include various actuators for brake hydraulic pressure control, such as the gate in valve 31, the electric motor 33, and the bypass valve 35 provided in the hydraulic pressure circuit 30 of the brake fluid shown in FIG. 2 described later. For example, the brake control unit 13 calculates the slip ratio of the wheels based on the wheel speed information detected by the wheel speed sensor 18d and the vehicle body speed information estimated from the wheel speed information, and controls the brake-related actuator 17 based on the slip ratio information to realize ABS (Antilock Braking System) control. Also, the brake control unit 13 realizes ESP (Electronic Stability Program) control by controlling the brake-related actuator 17.

[0020] In particular, the brake control unit 13 in the present embodiment performs brake control processing for anti-theft involving control of the brake booster 41 in response to theft detection, and this brake control processing will be described again.

[0021] Here, in the vehicle control device 10 of this example, the brake control unit 13 is constituted by a module integrated with the hydraulic pressure circuit 30 including the brake-related actuator 17. Here, the module in which the brake control unit 13 and the hydraulic pressure circuit 30 (including the internal brake-related actuator 17) are integrated is referred to as the "brake control module 26". As for the configuration of the brake control system, it may be divided into a module including a processor as the brake control unit 13 and a module including the hydraulic circuit 30. In some cases, the former module is provided in the passenger compartment and the latter module is provided in the engine room. However, in this example, the brake control module 26 in which the processor as the brake control unit 13 is also integrated is arranged in the engine room.

[0022] The theft determination unit 14 determines whether the vehicle 1 has been stolen based on detection signals from predetermined sensors in the sensors 18 and fraud detection signals from the key system control unit 11. The theft determination is made as a determination of whether a theft act against the vehicle 1 has been detected. Here, the theft act broadly means an act in which a thief tries to steal the vehicle 1. In the theft determination unit 14, the theft determination can be made based on, for example, detection signals from the motion sensor 18e or the human presence sensor 18f, captured images by the camera 18g, fraud detection signals from the key system control unit 11, and the like. For example, when attempting to steal the vehicle 1 by a specific method, it is conceivable that the vehicle 1 shows specific movements, such as shaking at a specific period or in a specific direction in response to the movements of the thief. In such a case, it is conceivable to make a determination as to whether the movement of the vehicle 1 estimated from the detection signal of the motion sensor 18e corresponds to a specific movement as a determination of whether one of the conditions for the establishment of the theft act is satisfied. Alternatively, it is also conceivable to define that a person other than a person pre-registered in the vehicle 1, such as the owner of the vehicle 1, getting into the driver's seat of the vehicle 1 and trying to move the vehicle 1 is one of the conditions for the establishment of the theft act. In such a case, it is conceivable to use the detection signal of the human presence sensor 18f and the captured image of the camera 18g for theft determination. Also, as for the theft determination, for example, it can also be simply made as a determination of whether a fraud detection signal is supplied from the key system control unit 11.

[0023] There are various conceivable specific methods for theft determination, and it is not limited to a specific method. As for theft detection, it is also conceivable to use detection signals from a plurality of sensors in combination. Further, theft detection can also be performed as a determination of whether some or all of a plurality of establishment conditions are satisfied.

[0024] When the theft determination unit 14 determines that the host vehicle is in a theft state in theft detection (that is, when a theft act is detected), it supplies a theft detection signal indicating that fact to the brake control unit 13.

[0025] FIG. 2 is a diagram showing a configuration example of a brake system provided in the vehicle control device 10. As a configuration of the brake system in the vehicle control device 10, as shown in the figure, a brake mechanism 20, a brake pedal 25, a brake stroke sensor 18c, a brake booster 41, a master cylinder 42, a reservoir tank 43, and a brake control module 26 are provided.

[0026] The brake pedal 25 is connected to the brake booster 41. The brake stroke sensor 18c detects the stroke amount of the brake pedal 25 and supplies a detection signal to the brake control unit 13.

[0027] The brake booster 41 is configured as an electric brake booster, and moves the primary piston of the master cylinder 42 based on the control of the brake control unit 13. For example, the brake booster 41 moves the primary piston by an amount corresponding to the depression amount of the brake pedal 25. Further, the brake booster 41 and the brake pedal 25 are mechanically connected so that brake hydraulic pressure can be supplied to the brake mechanism 20 in response to the operation of the brake pedal 25 in an emergency or the like.

[0028] The master cylinder 42 is, for example, of a tandem type, is connected to the reservoir tank 43, and is connected to the brake mechanism 20 via the hydraulic circuit 30. The master cylinder 42 generates brake hydraulic pressure and applies the brake hydraulic pressure to the brake mechanism 20 via the hydraulic circuit 30.

[0029] The brake mechanism 20 is configured as, for example, a disc brake mechanism, and is provided for each wheel of the wheels 2R and 2L as the front wheels and the wheels 3R and 3L as the rear wheels. As shown in the figure, the brake mechanism 20 includes a brake caliper 21, a brake piston 22, a brake pad 23, and a brake rotor 24. A hydraulic chamber (not shown) for receiving brake fluid is formed in the brake caliper 21, and brake hydraulic pressure is applied via a hydraulic circuit 30. The brake piston 22 is slidably housed in the brake caliper 21, and moves (slides) within the brake caliper 21 by the brake hydraulic pressure applied to the brake caliper 21 (the above hydraulic chamber).

[0030] The brake pad 23 is connected to the tip of the brake piston 22, and when the brake piston 22 moves by the brake hydraulic pressure, it is pressed against the brake rotor 24 that rotates integrally with the wheel. Thereby, the brake mechanism 20 brakes the vehicle 1 (the wheels).

[0031] The hydraulic circuit 30 is composed of two systems, a first hydraulic circuit 30a and a second hydraulic circuit 30b. The hydraulic circuit 30 corresponds to a cross pipe in this example. The first hydraulic circuit 30a is connected to the brake mechanism 20 provided for the wheels 2R and 3R, and the second hydraulic circuit 30b is connected to the brake mechanism 20 provided for the wheels 2L and 3L.

[0032] Since the first hydraulic circuit 30a and the second hydraulic circuit 30b have the same configuration, the same reference numerals will be used hereinafter for a common description. Also, regarding the hydraulic circuit 30, the terms upstream and downstream of the brake fluid are used, which mean upstream and downstream when the master cylinder 42 is regarded as the fluid source of the brake fluid.

[0033] The master cylinder 42 is provided with a supply / discharge port 42a and a supply / discharge port 42b. A first liquid passage L1 is connected to each of the supply / discharge port 42a and the supply / discharge port 42b. That is, the upstream end of the first liquid passage L1 is connected to the master cylinder 42 (supply / discharge port 42a, supply / discharge port 42b). A gate inlet valve 31 is inserted in the middle of the first liquid passage L1, and the downstream end of the first liquid passage L1 is connected to the connection portion between the downstream end of a seventh liquid passage L7, which will be described later, and the upstream end of a second liquid passage L2. A low-pressure chamber 40 is inserted in the middle of the seventh liquid passage L7, and a hydraulic pump 32 and a pulsation decompression mechanism 34 are inserted in the middle of the second liquid passage L2.

[0034] Also, the upstream end of an eighth liquid passage L8 is connected in the middle of the first liquid passage L1. Specifically, the upstream end of the eighth liquid passage L8 is connected to a portion of the first liquid passage L1 that is upstream of the gate inlet valve 31. A bypass valve 35 is inserted in the middle of the eighth liquid passage L8, and the downstream end of the eighth liquid passage L8 is connected to a portion of the second liquid passage L2 that is downstream of the hydraulic pump 32 and the pulsation decompression mechanism 34.

[0035] A third liquid passage L3 and a fourth liquid passage L4 are branched and connected to the downstream end of the second liquid passage L2. A pressure valve 36 is inserted in the middle of the third liquid passage L3, and a pressure valve 37 is inserted in the middle of the fourth liquid passage L4. In the case of this example, which is a cross pipe, the downstream end of the third liquid passage L3 is connected to the brake mechanism 20 (brake caliper 21) of the wheels (2L, 3L) as the left wheels, and the downstream end of the fourth liquid passage L4 is connected to the brake mechanism 20 (brake caliper 21) of the wheels (2R, 3R) as the right wheels. Note that the third liquid passage L3 and the fourth liquid passage L4 may be connected to the brake mechanism 20 of any wheel. For example, in the case of a left-right pipe, for example, if the first hydraulic circuit 30a is made to correspond to the front wheel side and the second hydraulic circuit 30b is made to correspond to the rear wheel side, the third liquid passage L3 and the fourth liquid passage L4 of the first hydraulic circuit 30a can be connected to the wheels 2R and 2L, respectively, and the third liquid passage L3 and the fourth liquid passage L4 of the second hydraulic circuit 30b can be connected to the wheels 3R and 3L, respectively.

[0036] In the third liquid passage L3, the upstream end of the fifth liquid passage L5 is connected to a portion that is upstream of the downstream end connected to the brake mechanism 20 and downstream of the pressure valve 36. Further, in the fourth liquid passage L4, the upstream end of the sixth liquid passage L6 is connected to a portion that is upstream of the downstream end connected to the brake mechanism 20 and downstream of the pressure valve 37.

[0037] In the fifth liquid passage L5 and the sixth liquid passage L6, a pressure reducing valve 38 and a pressure reducing valve 39 are inserted in the middle, respectively. The seventh liquid passage L7 is connected to the downstream ends of the fifth liquid passage L5 and the sixth liquid passage L6. In the seventh liquid passage L7, the low-pressure chamber 40 is inserted in a portion that is downstream of the connection portion with the downstream ends of the fifth liquid passage L5 and the sixth liquid passage L6. The low-pressure chamber 40 is provided for temporarily storing the brake fluid.

[0038] In the second liquid passage L2, the hydraulic pump 32 and the pulsation reducing mechanism 34 are inserted between the connection portion with the downstream end of the eighth liquid passage L8 and the connection portion with the downstream ends of the seventh liquid passage L7 and the first liquid passage L1. The hydraulic pumps 32 of the first hydraulic circuit 30a and the second hydraulic circuit 30b are driven by a common electric motor 33. The pulsation reducing mechanism 34 attenuates the pulsation of the brake fluid discharged from the hydraulic pump 32.

[0039] Here, in this example, the gate valve 31, the pressure reducing valve 38, and the pressure reducing valve 39 are normally closed solenoid valves that close when not energized and open when energized. On the other hand, the bypass valve 35, the pressure valve 36, and the pressure valve 37 are normally open solenoid valves that open when not energized and close when energized.

[0040] The gate valve 31, the electric motor 33, the bypass valve 35, the pressure valve 36, the pressure valve 37, the pressure reducing valve 38, and the pressure reducing valve 39 are controlled by the brake control unit 13.

[0041] Further, in this example, locking portions 50 are provided for the bypass valves 35 in both the first hydraulic circuit 30a and the second hydraulic circuit 30b. The locking portions 50 will be described later in detail.

[0042] When the brake hydraulic control such as ABS control and ESP control by the brake control unit 13 is not being performed, the gate inlet valve 31 as a normally closed valve, the pressure reducing valves 38 and 39 are in the closed state, and the bypass valve 35, the pressure increasing valves 36 and 37 as normally open valves are in the open state. Also, the electric motor 33 is not driven and the hydraulic pump 32 is stopped.

[0043] Here, when the driver depresses the brake pedal 25 while the brake control unit 13 is not performing brake hydraulic control such as ABS control, the brake hydraulic pressure generated in the master cylinder 42 is branched into the third hydraulic passage L3 and the fourth hydraulic passage L4 through the first hydraulic passage L1, the eighth hydraulic passage L8, and the second hydraulic passage L2 and supplied to the brake mechanism 20. Then, the brake mechanism 20 brakes the wheels with this brake hydraulic pressure.

[0044] On the other hand, during brake hydraulic control such as ABS control and ESP control, the brake control unit 13 controls to open the gate inlet valve 31 which is a normally closed valve and close the bypass valve 35 which is a normally open valve. Since the pressure increasing valves 36 and 37 are normally open valves and the pressure reducing valves 38 and 39 are normally closed valves as described above, depending on the above control, the gate inlet valve 31, the pressure increasing valve 36, and the pressure increasing valve 37 are in the open state, and the bypass valve 35, the pressure reducing valve 38, and the pressure reducing valve 39 are in the closed state. Also, the brake control unit 13 drives the electric motor 33 during brake hydraulic control such as ABS control and ESP control.

[0045] By performing the above control, the hydraulic pump 32 rotates due to the drive of the electric motor 33, and the brake fluid stored in the reservoir tank 43 is sucked into the first liquid passage L1 via the master cylinder 42 independently of the operation of the brake pedal 25. Then, the brake fluid sucked into the first liquid passage L1 is branched into the third liquid passage L3 and the fourth liquid passage L4 via the second liquid passage L2 through the gate inlet valve 31 and supplied to the brake mechanism 20. Then, by pressurizing this brake fluid pressure, the brake mechanism 20 brakes the wheels.

[0046] Also, when the brake control unit 13 reduces the hydraulic pressure applied to the brake mechanism 20, such as when temporarily weakening the braking force during ABS control, the bypass valve 35 and the pressurizing valves 36, 37 are each controlled to the closed state, and the pressure reducing valves 38, 39 are each controlled to the open state. At this time, the open state of the gate inlet valve 31 (normally closed valve) is maintained. As a result, the gate inlet valve 31 and the pressure reducing valves 38, 39 are in the open state, and the bypass valve 35 and the pressurizing valves 36, 37 are in the closed state. Also, the brake control unit 13 continues the driving state of the electric motor 33.

[0047] In this case, when the hydraulic pump 32 rotates due to the drive of the electric motor 33, the brake fluid in the brake mechanism 20 (brake caliper 21) flows into the seventh liquid passage L7 through the fifth liquid passage L5 and the sixth liquid passage L6 from the third liquid passage L3 and the fourth liquid passage L4, respectively. Then, the brake fluid that has flowed into the seventh liquid passage L7 is stored in the low-pressure chamber 40. As a result, the brake fluid pressure in the brake mechanism 20 is reduced, and the braking of the wheels by the brake mechanism 20 is relaxed.

[0048] <2. Anti-theft control method as an embodiment> In the present embodiment, the brake control unit 13 performs brake control for anti-theft. FIG. 3 is a functional block diagram showing functions according to an embodiment of a brake control unit 13 provided in a vehicle control device 10 in vehicle 1. As shown in the figure, the brake control unit 13 has a function as a brake control processing unit F1. The brake control processing unit F1 performs the following processing as brake control processing for theft prevention. That is, in response to the input of a predetermined signal in response to the detection of theft of vehicle 1, after the brake pedal 25 is stroked by a certain amount or more by the brake booster 41 and brake hydraulic pressure is applied to the brake mechanism 20, the first valve disposed in the hydraulic circuit 30, specifically, the bypass valve 35, is maintained in a closed state to maintain the hydraulic pressure application state to the brake mechanism 20, and the stroke of the brake pedal 25 by the brake booster 41 is released.

[0049] Specifically, when the theft determination unit 14 detects theft by the above-described theft determination, the brake control unit 13 starts the above-described brake control processing in response to the input of a theft detection signal, which is output as a signal for notifying that fact. In the brake control processing as described above, the brake pedal 25 is stroked by a certain amount or more by the brake booster 41 to apply brake hydraulic pressure to the brake mechanism 20. In this example, the stroke at this time is a full stroke, that is, until the brake pedal 25 reaches the bottom. Then, thereafter, the bypass valve 35 disposed in the hydraulic circuit 30 is maintained in a closed state to maintain the hydraulic pressure application state to the brake mechanism 20. And in the state where the hydraulic pressure application state to the brake mechanism 20 is maintained in this way, the stroke of the brake pedal 25 by the brake booster 41 is released.

[0050] By performing the above control, in response to the detection of theft of vehicle 1, vehicle 1 enters a brake hold state and the reaction force to the stepping force of the brake pedal 25 is reduced. That is, the brake pedal 25 becomes in a state of being loose and rattling. By reducing the reaction force of the brake pedal 25, it becomes possible to make thieves misjudge that the brake is malfunctioning, making it difficult for thieves to notice that the anti-theft control is activated, and thus reducing the thieves' desire to steal the vehicle 1, thereby improving the anti-theft effect. Further, even if a thief notices this control, the vehicle 1 is in the brake hold state, and it becomes extremely difficult for the thief to drive and steal the vehicle 1, and the anti-theft effect can also be improved in this regard.

[0051] Here, in order to enable the bypass valve 35 to be maintained in the closed state as described above, in this example, a locking portion 50 is provided for the bypass valve 35. With reference to FIGS. 4 and 5, a structural example of the locking portion 50 and the bypass valve 35 will be described. Note that in FIGS. 4 and 5, the structure of the bypass valve 35 shows a cross-sectional structure.

[0052] In this example, an example using a spool valve for the bypass valve 35 will be described, but a valve other than the spool valve can also be used for the bypass valve 35. The bypass valve 35 has, for example, a spool 35b, an electromagnetic coil 35c, and a biasing member 35d disposed inside a case 35e as an outer casing. A through hole 35a is formed in a substantially central portion of the case 35e, and pipe portions (in this example, the pipe portions of the eighth liquid passage L8: refer to FIG. 2) constituting the liquid passage of the brake fluid are connected to both ends of the through hole 35a.

[0053] The spool 35b is formed in a substantially cylindrical shape, and a plurality of portions where the diameter narrows are formed in the middle. In the spool 35b, the large-diameter portions are sliding portions (land portions) b that slide in contact with the inner wall of the case 35e. In this example, three sliding portions b are formed, and in the figure, they are denoted by reference numerals b1, b2, and b3, respectively.

[0054] The spool 35b constitutes a movable part in a solenoid actuator using an electromagnetic coil 35c, and is driven rightward in the drawing plane in response to energization of the electromagnetic coil 35c (see the transition from FIG. 4 to FIG. 5). The biasing member 35d has a biasing force in a direction to move the spool 35b in a direction opposite to this driving direction.

[0055] In FIG. 4, the electromagnetic coil 35c shows a non-energized state. In this state, the spool 35b is driven to the left side of the drawing plane by the biasing force of the biasing member 35d, and as shown in the drawing, the through-hole 35a is not blocked by any of the sliding parts b, and the valve is in an open state. That is, the bypass valve 35 as a normally open valve is realized.

[0056] On the other hand, when the electromagnetic coil 35c is energized, the spool 35b is driven rightward in the drawing plane against the biasing force of the biasing member 35d. In this state, the through-hole 35a is blocked by the sliding part b (in this example, the sliding part b3), and the valve is in a closed state.

[0057] The locking part 50 has a locking member 51 and a driving part 52. The locking member 51 is a columnar member such as a substantially cylindrical shape or a substantially prismatic shape in this example. The driving part 52 is configured to be able to drive the locking member 51 in the axial direction by energization. Although not shown, the driving part 52 is controlled by the brake control unit 13.

[0058] In the bypass valve 35 of this example, a hole part H1 and a hole part H2 are formed as a configuration for enabling maintenance of the closed state. As shown in the drawing, the hole part H1 is a hole part penetrating a part of the case 35e, and the hole part H2 is a hole part formed in any of the sliding parts b (in this example, the sliding part b1) of the spool 35b.

[0059] The locking part 50 is arranged at a position where the locking member 51 is inserted into the hole part H1 when the locking member 51 is driven in a direction to protrude from the driving part 52. Further, in the bypass valve 35, the hole H2 is formed at a position where it can communicate with the hole H1 in a state where the spool 35b is driven so that the bypass valve 35 is in a closed state.

[0060] When the bypass valve 35 is in the open state, the driving member 52 does not drive the locking member 51, and the locking member 51 is in a state where its tip is not inserted into the hole H2 as shown in FIG. 4.

[0061] On the other hand, when the bypass valve 35 is to be maintained in the closed state, the driving member 52 drives the locking member 51 in a direction protruding from the driving member 52. As a result, as shown in FIG. 5, the tip of the locking member 51 is inserted into the hole H2 through the hole H1. Thereby, the position of the spool 35b is fixed at a position where the bypass valve 35 is in the closed state, and the closed state of the bypass valve 35 is maintained.

[0062] FIG. 6 is a cross-sectional view for explaining a configuration example of the driving member 52 in the locking portion 50, and FIG. 6A shows the state before driving the locking member 51, and FIG. 6B shows the state after driving the locking member 51. As shown in the figure, the driving member 52 includes a first actuator 52a, a biasing member 52b, and a second actuator 52c. In this case, a hole 51a is formed in the locking member 51.

[0063] The first actuator 52a is configured as a solenoid actuator that translates a movable member, for example, in a rod shape. The biasing member 52b biases the locking member 51 in a direction protruding from the driving member 52. In the state before driving shown in FIG. 6A, the tip of the movable member of the first actuator 52a is inserted into the hole 51a of the locking member 51, and the locking member 51 is locked in a non-protruding state.

[0064] On the other hand, when the locking member 51 is projected for locking the bypass valve 35, the first actuator 52a is energized to release the locked state of the locking member 51. Then, by the biasing force of the biasing member 52b, the locking member 51 is driven in the projecting direction. That is, the locked state of the bypass valve 35 shown in FIG. 5 is realized.

[0065] Here, in the drive unit 52, the second actuator 52c is provided as an actuator for returning the projected locking member 51 to the non-projected state. As the second actuator 52c, for example, an actuator as a motor is used. For example, a gear rotated by a motor as the second actuator 52c is provided, and a rack portion meshing with the gear is formed on the side surface portion of the locking member 51. Thereby, by energizing the second actuator 52c, it becomes possible to return the position of the locking member 51 to the non-projected state position against the biasing force by the biasing member 52b. After returning the locking member 51 to the non-projected state position in this way, by inserting the tip of the movable member of the first actuator 52a into the hole portion 51a, it becomes possible to return to the state before driving shown in FIG. 6A.

[0066] For example, by adopting the configuration shown in FIG. 6, after the bypass valve 35 is locked, it becomes possible to return the locking portion 50 to a state where the bypass valve 35 can be locked again.

[0067] Note that the configuration related to maintaining the closed state of the bypass valve 35 described above is merely an example and is not limited to this configuration. For example, the number of the sliding portions b is not limited to three, and at least one is sufficient. Which of the sliding portions b is provided with the hole portion H2 is arbitrary. Further, the hole portion H2 is not limited to being provided in the sliding portion b, and it is also conceivable to provide the hole portion H2 in a portion other than the sliding portion b in the spool 35b. Also in the application to other than the spool valve, similarly, a configuration may be adopted in which the position of the member that controls the opening and closing of the valve is mechanically locked to the position where the valve is in the closed state.

[0068] Also, regarding the configuration for returning the locking portion 50 to a state where the bypass valve 35 can be locked, the configuration exemplified above is merely an example, and of course, other configurations can be adopted.

[0069] <3. Processing Procedure> Referring to the flowchart of FIG. 7, an example of a specific processing procedure for realizing anti-theft control as an embodiment will be described. The processing shown in FIG. 7 is executed by the CPU of the brake control unit 13 in accordance with a program stored in a storage medium such as a ROM provided in the brake control unit 13, for example.

[0070] First, in step S101, the brake control unit 13 waits until theft detection occurs. That is, in this example, it performs a process of waiting until the above-described theft detection signal is input from the theft determination unit 14.

[0071] When a theft detection signal is input and a determination result that theft has been detected is obtained, the brake control unit 13 proceeds to step S102 and controls the brake booster 41 to stroke the brake pedal 25. As described above, in this example, regarding the control of this stroke, control is performed to fully stroke the brake pedal 25.

[0072] In step S103 following step S103, the brake control unit 13 controls the pressure reducing valves 38 and 39 to open. By this control, the brake hydraulic pressure generated by the stroke control in step S102 is supplied not only to the brake caliper 21 in the brake mechanism 20 but also to the low-pressure chamber 40.

[0073] Here, generally, the volume of the brake fluid is in the master cylinder 42 > the brake caliper 21 (the hydraulic chamber in the brake mechanism 20). Therefore, by supplying the hydraulic pressure caused by the pedal stroke to the low-pressure chamber 40 as described above, it becomes possible to reduce the amount of brake fluid remaining on the master cylinder 42 side after the pedal stroke. That is, it becomes possible to make the brake pedal 25 looser. Accordingly, it is possible to increase the possibility that a thief misidentifies it as a brake failure, and it is possible to further reduce the thief's willingness to steal the vehicle, thereby improving the anti-theft effect.

[0074] Note that the timing for opening the pressure reducing valves 38 and 39 is not limited to after the pedal stroke by the brake booster 41. That is, the order of step S102 and step S103 may be reversed.

[0075] In step S104 following step S103, the brake control unit 13 performs closed control of the bypass valve 35. Then, in step S105 following step S104, the brake control unit 13 performs drive control of the locking member 51. That is, by controlling the drive unit 52 (the first actuator 52a) to drive the locking member 51 in the protruding direction, the bypass valve 35 is maintained in the closed state. As a result, in the master cylinder 42, the state where the brake hydraulic pressure is released is maintained, and the reaction force against the stepping force of the brake pedal 25 is reduced (that is, the brake pedal 25 becomes loose and wobbly). In addition, since the application state of the brake hydraulic pressure in the brake caliper 21 is maintained, the vehicle 1 is in the brake hold state.

[0076] In response to executing the process of step S105, the brake control unit 13 ends the series of processes shown in FIG. 5.

[0077] Although the description with reference to the drawings is omitted, if the thief gives up stealing the vehicle 1 after this control for theft prevention is activated and leaves the vehicle 1, for example, it is conceivable to return the vehicle 1 to the state before this control is activated. For this purpose, it is only necessary to release the locked state (maintenance of the closed state) of the bypass valve 35. Specifically, in this example, the brake control unit 13 drives the second actuator 52c in the drive unit 52 to return the locking member 51 to the non-protruding position. As a result, the bypass valve 35 returns to the open state by the biasing force of the biasing member 35d, and the brake fluid can be returned to the upstream side (master cylinder 42, reservoir tank 43) via the eighth liquid passage L8.

[0078] Also, at this time, as described above, by driving the first actuator 52a and inserting the tip of the movable member of the first actuator 52a into the hole 51a of the locking member 51, it becomes possible to return to a state where the main control for theft prevention can be executed again.

[0079] <4. Anti-theft control method as another example in the embodiment> Here, as can be understood from the description so far, in order to realize the anti-theft control as an embodiment, it is necessary for the brake control unit 13 to be energized. For this reason, if the thief takes a measure to remove the power connector for supplying power to the brake control unit 13 before theft detection in order to avoid activation of this control, the anti-theft effect by this control cannot be obtained. Also, since the brake booster 41 is also used for this control, if a measure is taken to remove the power connector for supplying power to the brake booster 41, similarly, the anti-theft effect by this control cannot be obtained.

[0080] Therefore, as another example in the embodiment, a configuration is proposed in which the power supply path to the brake booster 41 and the power supply path to the brake control unit 13 are duplicated. By duplicating such a power supply path, even if one power supply connector is removed, it is possible to obtain a state where power can be supplied by the duplicated other power supply path, and this control can be activated.

[0081] Here, when duplicating the power supply path, it is desirable to take measures to make it difficult to remove the two power supply connectors simultaneously. An example thereof is shown in FIG. 8. FIG. 8 shows a configuration example of the power input section of the brake control module 26 including the brake control unit 13. For example, as shown in the figure, in the duplicated power supply path, the configuration of the power input section is devised so that it becomes difficult to remove the power supply connector 62 of the other power supply path unless the power supply connector 61 of one power supply path is removed. Specifically, in the example of FIG. 8, the insertion positions of the power supply connector 61 and the power supply connector 62 are set such that the power supply connector 61 covers the power supply connector 62 in the state where the power supply connector 61 and the power supply connector 62 are inserted.

[0082] In making it difficult to remove the two power supply connectors simultaneously, for example, setting the insertion position of one power supply connector on the opposite side of the insertion position of the other power supply connector is also conceivable.

[0083] Also, although the configuration of the power input section of the brake control module 26 has been described here, similar measures are to be taken on the brake booster 41 side as well.

[0084] FIG. 9 is a flowchart showing an example of the procedure of the process to be executed in another example of the embodiment. Note that as the process shown in FIG. 9, the CPU of the brake control unit 13 also executes according to a program stored in a storage medium such as a ROM provided in the brake control unit 13, for example. Here, in FIG. 9, for the processes that are the same as the processes already described in FIG. 7, the same step numbers are assigned and the description is omitted.

[0085] In this case, if the brake control unit 13 determines in step S101 that theft has not been detected, the process proceeds to step S201 to determine whether a disconnection of one of the power supplies has been detected. Specifically, it is determined whether a disconnection of at least one (i.e., at least one of the total four power supply paths) has been detected among the duplicated power supply paths of the brake booster 41 and the brake control unit 13 (brake control module 26). In step S201, if no disconnection of any power supply path is detected and the condition that a disconnection of one of the power supplies has been detected is not satisfied, the brake control unit 13 returns to step S101.

[0086] On the other hand, if a disconnection of at least one of the power supply paths is detected and the condition that a disconnection of one of the power supplies has been detected is satisfied, the brake control unit 13 proceeds to step S102 with the process. Note that redundant explanations for the processes from step S102 to step S105 are avoided.

[0087] By adding the process of step S201 as described above, even if any of the power connectors in the brake booster 41 and the brake control module 26 is unplugged, this control can be activated while power supply is being performed by the other power connectors. That is, it is possible to implement a countermeasure against avoiding the activation of this control by unplugging the power connectors of the brake booster 41 or the brake control module 26.

[0088] <5. Modification Example> Note that the embodiments are not limited to the specific examples described above, and various modification examples can be adopted. For example, in the above, an example of full stroke was given as the stroke of the brake pedal 25 by the brake booster 41, but it is not limited to full stroke. The stroke of the brake pedal 25 by the brake booster 41 may be at least a certain amount or more.

[0089] In the above description, a disk brake mechanism is exemplified as the brake mechanism 20. However, the present invention can also be suitably applied when a brake mechanism of another type, such as a drum brake mechanism, is adopted.

[0090] In the above description, the vehicle 1 as an engine vehicle equipped only with an engine as a driving source of the wheels is exemplified. However, the present invention can also be suitably applied to, for example, a hybrid vehicle equipped with both an engine and a motor as driving sources of the wheels, or an electric vehicle equipped only with a motor as a driving source of the wheels.

[0091] <6. Summary of Embodiment> As described above, the vehicle control device (the same 10) as an embodiment is a vehicle control device in a vehicle (the same 1) having a brake mechanism (the same 20), and includes one or more processors (the CPU of the brake control unit 13) and one or more storage media (the ROM of the brake control unit 13) in which a program executed by the one or more processors is stored. The program includes one or more instructions. The instruction causes the one or more processors to execute a brake control process of releasing the stroke of the brake pedal by the brake booster while maintaining the hydraulic pressure application state to the brake mechanism by maintaining the first valve (the bypass valve 35) arranged in the brake hydraulic circuit in a closed state after applying a brake hydraulic pressure to the brake mechanism by stroking the brake pedal by a certain amount or more by the brake booster in response to the input of a predetermined signal in response to the detection of vehicle theft. Thereby, in response to the detection of vehicle theft, the vehicle enters a brake hold state and the reaction force against the stepping force of the brake pedal is reduced (the brake pedal becomes a floppy and rattling state). By reducing the reaction force of the brake pedal, it becomes possible to mislead a thief into thinking that the brake is malfunctioning, making it difficult for the thief to notice that the anti-theft control has been activated while reducing the thief's incentive to steal the vehicle, thereby improving the anti-theft effect. Also, even if the thief notices this control, the vehicle is in a brake hold state, making it extremely difficult for the thief to drive away with the vehicle, and thus also improving the anti-theft effect in this regard.

[0092] Here, as measures that a thief could take to release the brake hold state by this control, it can be assumed that: 1) replace the brake control unit that performs this control; 2) bleed the hydraulic pressure from the brake caliper. However, for 1), when the brake control unit is integrated with the hydraulic circuit, high-pressure brake fluid will spray out the moment an attempt is made to remove the brake control unit, making replacement difficult. Also, for 2), when the hydraulic pressure is bled from the caliper, the vehicle will enter a state where no braking force is applied at all, increasing the difficulty of stealing the vehicle. Also, even if the thief gives up stealing the vehicle and leaves it due to the activation of this control, the vehicle can be appropriately restored to its state before the activation of this control by canceling the control. At this time, it is desirable to ensure that the cancellation of this control can only be performed by a predetermined organization, such as a public organization like the police or a neutral organization like a dealer, using a predetermined tool.

[0093] Also, in the vehicle control device as an embodiment, the power supply path to the brake booster that is an electric booster and the power supply path to the brake control unit (same 13) having a processor that executes brake control processing are duplicated, and the brake control processing is started on the condition of either the input of a predetermined signal or the detection of a power cut in any one of the power supply paths (see Fig. 9). Thus, even if an attempt is made to prevent the activation of this control by unplugging the power connector of the brake booster or the brake control unit, it is possible to obtain a power supply state by means of the other duplicated power supply path, and the activation of this control becomes possible. Therefore, it is possible to increase the difficulty of preventing the activation of this control and to improve the anti-theft effect.

[0094] Furthermore, in the vehicle control device according to the embodiment, the first valve is a normally open valve, and includes a locking portion (50) for locking the first valve in the closed state. In the brake control process, the locking portion is driven to lock the first valve in the closed state, thereby maintaining the hydraulic pressure application state to the brake mechanism. Thereby, even if the brake control unit loses power after the first valve as a normally open valve is controlled to the closed state, it is possible to maintain the first valve in the closed state, that is, to maintain the brake hold state and to maintain the brake pedal in the free state. Therefore, it is possible to increase the difficulty of preventing the activation of this control by unplugging the power connector of the brake control unit and to improve the anti-theft effect.

[0095] Furthermore, in the vehicle control device according to the embodiment, in the brake control process, the brake pedal is fully stroked with a stroke of a certain amount or more. Thereby, it is possible to realize a strong brake hold state in response to the detection of vehicle theft. Therefore, it is possible to increase the difficulty for a thief to drive away the vehicle and improve the anti-theft effect.

[0096] Also, in the vehicle control device according to the embodiment, the brake hydraulic circuit is provided with a second valve for discharging the hydraulic pressure of the brake mechanism to a hydraulic chamber (low-pressure chamber 40) downstream of the first valve. In the brake control process, when the brake pedal is stroked, the second valve is opened to supply the hydraulic pressure from the master cylinder to the hydraulic chamber. Generally, the volume of the brake fluid is the hydraulic chamber in the master cylinder > brake mechanism. Therefore, by supplying the hydraulic pressure caused by the pedal stroke to the hydraulic chamber as described above, it becomes possible to reduce the amount of brake fluid remaining on the master cylinder side after the pedal stroke. That is, it becomes possible to make the brake pedal lighter. Therefore, it is possible to increase the possibility that a thief misidentifies it as a brake failure, and it becomes possible to further reduce the thief's desire to steal the vehicle, thereby improving the anti-theft effect.

Explanation of Signs

[0097] 1 Vehicle 10 Vehicle control device 13 Brake control unit 14 Theft determination unit 17 Brake-related actuator 18 Sensors 18c Brake stroke sensor 20 Brake mechanism 26 Brake control module 30, 30a, 30b Hydraulic circuit 35 Bypass valve 35a Through hole 35b Spool b1, b2, b3 Sliding part 35c Electromagnetic coil 35d Biasing member 35e Case H1, H2 Hole part 38, 39 Pressure reducing valve 40 Low pressure chamber 41 Brake booster 42 Master cylinder 43 Reservoir tank F1 Brake control processing unit 50 Locking part 51 Locking member 51a Hole part 52 Driving part 52a First actuator 52b Biasing member 52c Second actuator 61 First connector 62 Second connector

Claims

1. A vehicle control device in a vehicle having a braking mechanism, comprising: one or more processors; one or more storage media storing programs executed by the one or more processors, the program includes one or more instructions, the instructions cause the one or more processors to in response to the input of a predetermined signal in response to theft detection of the vehicle, after stroking the brake pedal by a certain amount or more by a brake booster to apply brake hydraulic pressure to the braking mechanism, and then maintaining the first valve disposed in the brake hydraulic circuit in a closed state to maintain the hydraulic pressure application state to the braking mechanism, release the stroke of the brake pedal by the brake booster Brake control process to execute Vehicle control device.

2. The power supply path to the brake booster which is an electric booster and the power supply path to the brake control unit having the processor that executes the brake control process are duplicated, The brake control process is started on the condition that either the input of the predetermined signal or the power failure is recognized in any one of the power supply paths. The vehicle control device according to claim 1.

3. The first valve is a normally open valve, comprises a locking portion for locking the first valve in a closed state, In the brake control process, by driving the locking portion to lock the first valve in a closed state, the hydraulic pressure application state to the braking mechanism is maintained. The vehicle control device according to claim 1 or claim 2.

4. In the brake control process, as the stroke of a certain amount or more, the brake pedal is fully stroked. The vehicle control device according to any one of claims 1 to 3.

5. In the brake hydraulic circuit, a second valve for discharging the hydraulic pressure of the braking mechanism to a hydraulic chamber is provided downstream of the first valve, In the brake control process, when the brake pedal is stroked, the second valve is opened to supply the hydraulic pressure from the master cylinder to the hydraulic chamber. The vehicle control device according to any one of claims 1 to 4.

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