JP2013049369A - Stroke simulator, master cylinder including the same, and brake system using the master cylinder - Google Patents

Abstract

PROBLEM TO BE SOLVED: To start operation of an input shaft with a smaller input at the start of operation, thereby starting the operation of a stroke simulation function more smoothly.SOLUTION: At the start of operation of an input shaft 4, an electromagnet 29 of an auxiliary power output part 28 is excited to N-pole, thereby adding auxiliary power to a simulator operation piston 14 in an advancing direction by attraction between the electromagnet 29 and a permanent magnet 30 excited to S-pole. Input of the input shaft 4 is reduced at the start of operation, accordingly. The electromagnet 29 is excited to S-pole when the input shaft 4 performs backward stroke, thereby adding auxiliary power to the simulator operation piston 14 in a backward direction due to repulsion between the electromagnet 29 and the permanent magnet 30. Power to be supplied to the electromagnet 29 is controlled to obtain desired hysteresis.

Description

  The present invention relates to a technical field of a stroke simulator that is used in a brake system or the like and generates a reaction force according to a stroke, a technical field of a master cylinder having the stroke simulator, and a technical field of a brake system using the master cylinder. Is. In the description of the specification of the present invention, the relationship between the front and rear directions is that the direction in which the input shaft moves when the brake pedal is depressed is “front”, and the direction in which the input shaft returns when the brake pedal is released is “rear”. .

  In automobiles such as passenger cars, development of hybrid cars and electric cars is progressing. Along with this, various regenerative cooperative brake systems that use regenerative brakes and friction brakes in cooperation have been developed in automobile brake systems. This regenerative cooperative brake system detects the depression stroke of the brake pedal, and based on the detected stroke, the control unit (Electric control unit: ECU) calculates the braking force by the regenerative brake and the braking force by the friction brake, The vehicle is braked with the calculated braking force.

  In such a regenerative cooperative brake system, since the control unit determines the braking force based on the depression stroke of the brake pedal, the reaction force corresponding to the depression stroke of the brake pedal is not transmitted to the driver. Therefore, in order to enable the driver to recognize a reaction force according to the depression stroke of the brake pedal, a master cylinder having a pedal feel simulator unit has been proposed (for example, see Patent Document 1).

  FIG. 5 is a diagram schematically showing a master cylinder having a pedal feel simulator portion described in Patent Document 1. As shown in FIG. In the figure, 1 is a master cylinder, 2 is a tandem master cylinder section for generating brake fluid pressure of a friction brake, 3 is a pedal feel simulator section (stroke simulator) provided integrally with the tandem master cylinder section 2, and 4 is a brake An input shaft that strokes in response to depression of a pedal (not shown in FIG. 5), 5 is a stroke sensor that detects the stroke of the input shaft 4, and 6 is a reservoir tank that stores brake fluid.

The tandem master cylinder portion 2 has a primary piston 7, a secondary piston 8, a primary hydraulic pressure chamber 9 defined by the primary piston 7 and the secondary piston 8, and a secondary defined by the secondary piston 8, similarly to a conventionally known tandem master cylinder. The hydraulic chamber 10 includes a primary spring 11 that constantly biases the primary piston 7 toward the non-operating position, and a secondary spring 12 that biases the secondary piston 8 toward the non-operating position. The primary hydraulic chamber 9 is a brake cylinder of one brake system (not shown in FIG. 5).
Is connected to the reservoir tank 6 at the non-operating position of the illustrated primary piston 7 and is cut off from the reservoir tank 6 when the primary piston 7 moves forward, and a brake fluid pressure is generated in the primary fluid pressure chamber 9. The The secondary hydraulic chamber 10 always communicates with a brake cylinder (not shown in FIG. 5) of the other brake system, communicates with the reservoir tank 6 at a non-operating position of the illustrated secondary piston 8, and the secondary piston 8 moves forward. Then, the reservoir tank 6 is cut off, and the brake fluid pressure is generated in the secondary fluid pressure chamber 10.

Further, the tandem master cylinder portion 2 has a power chamber 13 between the primary piston 7 and the cylinder wall. The power chamber 13 is supplied with hydraulic fluid from a power source (not shown) when the brake is operated. In this case, the hydraulic fluid is supplied so that the hydraulic pressure in the power chamber 13 becomes a hydraulic pressure corresponding to the braking force by the friction brake calculated by the control unit.

  The pedal sensation simulator unit 3 always places the simulator operating piston 14 operated by the input shaft 4, the simulator operating hydraulic pressure chamber 15 in which the simulator operating hydraulic pressure is generated by the operation of the simulator operating piston 14, and the simulator operating piston 14 at the non-operating position. And a simulator operating piston return spring 16 composed of a coil spring that is biased in the direction, and a pedal feel simulator cartridge 17. Further, the pedal feel simulator cartridge 17 includes a first reaction force simulator piston 18 (corresponding to a reaction force simulator member of the present invention) to which the simulator operation hydraulic pressure in the simulator operation hydraulic pressure chamber 15 is applied, and a first reaction force simulator piston 18. The first reaction force simulator spring 19 (equivalent to the reaction force simulator member of the present invention) that normally urges the first reaction force simulator spring 19 and the second reaction force simulator piston 20 that supports the first reaction force simulator spring 19 (the present invention). And a second reaction force simulator spring 21 (corresponding to the reaction force simulator member of the present invention) that constantly urges the second reaction force simulator piston 20 toward the non-actuated position.

  In the pedal feeling simulator unit 3, when the brake pedal is not depressed, the simulator operating piston 14 is in the non-operating position shown in FIG. In this state, the simulator working fluid pressure chamber 15 communicates with the reservoir tank 6, and the simulator working fluid pressure chamber 15 is at atmospheric pressure without generating simulator working fluid pressure. Accordingly, the first reaction force simulator piston 18 and the second reaction force simulator piston 20 are in the non-actuated position shown in FIG.

When the brake pedal is depressed, the input shaft 4 moves forward (leftward in FIG. 5), so that the simulator operating piston 14 moves forward (actuates) while flexing the simulator operating piston return spring 16 elastically. When the simulator working fluid pressure chamber 15 is shut off from the reservoir tank 6 by the operation of the simulator working piston 14, the simulator working fluid pressure is generated in the simulator working fluid pressure chamber 15. This simulator hydraulic pressure acts on the first reaction force simulator piston 18. When the simulator operating fluid pressure increases to a predetermined fluid pressure, the first reaction force simulator piston 18 moves downward in FIG. 5 while pressing the first reaction force simulator spring 19 to bend elastically. In addition, the second reaction force simulator piston 20 moves (actuates) downward in FIG. 5 while bending the second reaction force simulator spring 21 by the pressing force of the first reaction force simulator piston 18. As a result, the first and second reaction force simulator springs 19, 2
1 acts as a reaction force on the first reaction force simulator piston 18 according to the amount of bending.

When the acting force on the first reaction force simulator piston 18 due to the simulator operating hydraulic pressure and the acting force on the first reaction force simulator piston 18 due to the first reaction force simulator spring 19 are balanced, the first and second reaction forces are obtained. The movement of the simulator pistons 18 and 20 stops. At this time, the simulator working fluid pressure in the simulator working fluid pressure chamber 15 is a fluid pressure corresponding to the depression stroke of the brake pedal. Then, the reaction force of the first reaction force simulator piston 18 is converted into the simulator operation hydraulic pressure and acts on the simulator operation piston 14, and further the reaction force is transmitted from the simulator operation piston 14 to the brake pedal via the input shaft 4. . As a result, the driver recognizes the reaction force corresponding to the depression stroke of the brake pedal from the brake pedal. In this way, the pedal feel simulator unit 3 exhibits a stroke simulator function.

The pedal feel characteristic diagram (that is, the characteristic diagram of the reaction force F with respect to the stroke S of the brake pedal) in the pedal feel simulator unit 3 configured as described above is the characteristic diagram shown in FIG. That is, in the pedal sensory characteristic diagram, the reaction force is relatively small with respect to the increase in stroke at the initial operation of the pedal sensor simulator unit 3, and when the stroke is increased by a predetermined amount, the reaction force is relatively large with respect to the increase in stroke. Draw a curved characteristic curve.

  On the other hand, in the master cylinder 1, when the brake pedal is not depressed, the tandem master cylinder portion 2 and the pedal feel simulator portion 3 are both in the inoperative state shown in FIG. That is, hydraulic fluid is not supplied to the power chamber 13 from the power source, and both the primary piston 7 and the secondary piston 8 are in the non-operating position shown in FIG. Therefore, both the primary hydraulic pressure chamber 9 and the secondary hydraulic pressure chamber 10 communicate with the reservoir tank 6, and no brake hydraulic pressure is generated in the primary hydraulic pressure chamber 9 and the secondary hydraulic pressure chamber 10. Further, the simulator working fluid pressure chamber 15 communicates with the reservoir tank 6, and no simulator working fluid pressure is generated in the simulator working fluid pressure chamber 15.

  When the brake pedal is depressed, the input shaft 4 moves forward as described above, and the stroke of the input shaft 4 is detected by the stroke sensor 5. A control unit (not shown) drives and controls the power source based on the stroke of the input shaft 4 from the stroke sensor 5 (that is, the depression stroke of the brake pedal). Thereby, hydraulic fluid is supplied from the power source to the power chamber 13, and the primary piston 7 and the secondary piston 8 move forward. Then, both the primary hydraulic pressure chamber 9 and the secondary hydraulic pressure chamber 10 are disconnected from the reservoir tank 6, and brake hydraulic pressure is generated in the primary hydraulic pressure chamber 9 and the secondary hydraulic pressure chamber 10. These brake fluid pressures are respectively supplied to two corresponding brake cylinders, and the corresponding wheels of the automobile are braked.

  When the hydraulic fluid pressure in the power chamber 13 becomes a hydraulic pressure corresponding to the depression stroke of the brake pedal, the control unit stops the power source. Then, both the primary piston 7 and the secondary piston 8 are stopped, and the brake fluid pressure in the primary fluid pressure chamber 9 and the secondary fluid pressure chamber 10 both becomes a fluid pressure corresponding to the depression stroke of the brake pedal. That is, the brake is applied to the wheel with a braking force corresponding to the depression stroke of the brake pedal.

  At this time, as described above, the pedal feeling simulator unit 3 transmits a reaction force corresponding to the depression stroke of the brake pedal to the brake pedal by the stroke simulator function. Therefore, the driver recognizes this reaction force and senses that the brake is applied to the wheel with the braking force corresponding to the depression stroke of the brake pedal.

  When the brake pedal is released, the input shaft 4 strokes backward (in the non-actuated position), and the stroke of the input shaft 4 is detected by the stroke sensor 5. The control unit controls a control valve (not shown) based on the stroke detected by the stroke sensor 5 and discharges the hydraulic fluid in the power chamber 13 to the reservoir tank 6. Thereby, the hydraulic pressure in the power chamber 13 is lowered, and the primary piston 7 and the secondary piston 8 are moved backward by the urging force of the primary spring 11 and the secondary spring 12, respectively. When the hydraulic pressure in the power chamber 13 becomes atmospheric pressure, the primary piston 7 and the secondary piston 8 are both in the inoperative position shown in FIG. 5, and the brakes of the wheels are released.

On the other hand, the simulator operating piston 14 moves backward by the biasing force of the simulator operating piston return spring 16 as the input shaft 4 strokes backward. When the simulator operating piston 14 is in the vicinity of the non-operating position, the simulator operating hydraulic pressure chamber 15 communicates with the reservoir tank 6 and the simulator operating hydraulic pressure in the simulator operating hydraulic pressure chamber 15 decreases. In the state where the simulator operating piston 14 is in the non-operating position shown in FIG. 5, the hydraulic pressure in the simulator operating hydraulic pressure chamber 15 is atmospheric pressure. Thereby, both the first reaction force simulator piston 18 and the second reaction force simulator piston 20 are in the non-actuated positions shown in FIG. In addition,
The terms and symbols used for each component are not the same terms and symbols as those described in Patent Document 1.

Japanese Patent No. 4510388.

  By the way, the pedal sensation simulator unit 3 described in Patent Document 1 includes a plurality of springs including a simulator operation piston return spring 16, a first reaction force simulator spring 19, and a second reaction force simulator spring 21. On the other hand, in order for the pedal sensation simulator unit 3 to start operating, the simulator operating piston 14 needs to operate, but the simulator operating piston 14 must operate while bending these plural springs. For this reason, when the operation of the pedal sensation simulator unit 3 starts, the force for starting the operation of the simulator operation piston 14 increases. Therefore, since the input shaft 4 needs to apply a large input when the operation of the pedal feel simulator unit 3 is started, a large pedal effort is required. As a result, there is a problem that it is difficult to smoothly start the operation of the stroke simulation function.

  The present invention has been made in view of such circumstances, and its purpose is to enable the input shaft to start operating with a smaller input at the time of starting the operation, thereby further starting the operation of the stroke simulation function. To provide a stroke simulator that can be performed more smoothly, a master cylinder having the stroke simulator, and a brake system using the master cylinder.

  In order to solve the above-described problems, a stroke simulator according to the present invention includes an input shaft that is actuated by input, a simulator actuated piston that is actuated by the input shaft, and a direction in which the simulator actuated piston is in a non-actuated position. A simulator-operated piston return spring that urges the simulator-operated piston, a reaction-force simulator member that outputs a reaction force based on the input of the input shaft to the simulator-operated piston by the operation of the simulator-operated piston, and at least the operation of the input shaft is started. And an auxiliary power unit that sometimes applies auxiliary power to the simulator operating piston in the operating direction of the simulator operating piston.

  The stroke simulator according to the present invention includes a control unit that controls energization (power supply) to the electromagnet, and the auxiliary power unit is disposed in the electromagnet disposed in the housing and the simulator operating piston. And a magnet excited by either one of the magnetic poles of the N pole and the S pole, and when the operation of the input shaft is started at least by the controller, the electromagnet is set to the other magnetic pole of the N pole and the S pole. By conducting energization control on the electromagnet so as to be excited, the auxiliary power is applied to the simulator operating piston by an attractive force between the electromagnet and the magnet.

  Furthermore, in the stroke simulator according to the present invention, the auxiliary power unit applies auxiliary power to the simulator operating piston in the forward direction of the simulator operating piston during the forward stroke of the input shaft, and assists during the backward stroke of the input shaft. Power is applied to the simulator operating piston in the backward direction of the simulator operating piston.

Furthermore, the stroke simulator according to the present invention includes a control unit that controls energization to the electromagnet, and the auxiliary power unit is disposed in the electromagnet disposed in the housing and the simulator operation piston, and the N pole and A magnet excited on one of the magnetic poles of the S pole, and the control unit is configured to excite the electromagnet on the other magnetic pole of the N pole and the S pole at least when the operation of the input shaft is started. The auxiliary power unit applies the auxiliary power to the simulator operating piston by the attractive force between the electromagnet and the magnet, and the control unit moves the input shaft back and forth. Sometimes the electromagnet is energized and controlled so that the electromagnet is excited to the same magnetic pole as that of the magnet disposed on the simulator operating piston. And in is characterized in that the auxiliary power unit is added to the auxiliary power by the repulsive force between the magnet and the electromagnet to the simulator actuation piston.

  Furthermore, the master cylinder according to the present invention includes a stroke simulator that outputs a reaction force based on an input of an input shaft and a master cylinder piston that generates a hydraulic pressure based on an input of the input shaft. The simulator is any one of the aforementioned stroke simulators of the present invention.

  Further, the brake system according to the present invention includes a brake pedal, a master cylinder that operates when the brake pedal is depressed and generates a brake fluid pressure based on the depression of the brake pedal, and the brake generated by the master cylinder. A brake system including a brake cylinder that generates a braking force with hydraulic pressure is characterized in that the master cylinder is the aforementioned master cylinder.

  According to the stroke simulator according to the present invention configured as described above, the master cylinder having the same, and the brake system, at least when the operation of the stroke simulator starts, the auxiliary power unit assists the simulator operation piston simulator operation piston in its operation direction. Adding power. Therefore, even if the simulator operating piston is operated while bending a plurality of springs arranged in the stroke simulator, the force at which the simulator operating piston starts to operate can be reduced when the operation of the stroke simulator starts. Thereby, when the operation of the stroke simulator is started, the input shaft can be moved forward (operated) with a smaller input. As a result, according to the brake system using the master cylinder having the stroke simulator, the brake pedal can be depressed with a smaller pedal effort and the stroke simulator function of the stroke simulator can be started more smoothly. Can do.

  The auxiliary power unit has an electromagnet disposed in the housing and a magnet disposed in the simulator operating piston. Hysteresis is added to the stroke simulator by controlling the amount of current flowing through the electromagnet and controlling the attractive force and repulsive force between the electromagnet and the magnet appropriately during the forward stroke of the input shaft and the reverse stroke of the input shaft. You can have it. In that case, since the energization control with respect to an electromagnet can be performed easily, desired hysteresis can be obtained easily. Further, by controlling the energization amount to the electromagnet, the input of the input shaft, that is, the pedal effort can be made variable. This makes it possible to flexibly respond to the setting of the pedal effort of the brake pedal according to the user's request.

It is a figure showing typically a master cylinder which has an example of an embodiment of a stroke simulator concerning the present invention, and a brake system using this master cylinder. It is the elements on larger scale of the II section in FIG. It is a figure explaining the electricity supply control of the electromagnet of the stroke simulator of the example shown in FIG. It is a figure which shows the flow for performing electricity supply control of an electromagnet. It is a figure which shows typically the master cylinder which has the conventional pedal feeling simulator part described in patent document 1. FIG. FIG. 6 is a pedal feel characteristic diagram of the pedal feel simulator section shown in FIG. 5.

Hereinafter, embodiments for carrying out the present invention will be described with reference to the drawings.
FIG. 1 is a diagram schematically showing a master cylinder having an example of an embodiment of a stroke simulator according to the present invention, and a brake system using the master cylinder. FIG. 2 is a partially enlarged view of a portion II in FIG. In addition, the same code | symbol is attached | subjected to the component of this invention same as the component of the master cylinder which has the stroke simulator shown in above-mentioned FIG. 5, and those detailed description is abbreviate | omitted.

As shown in FIGS. 1 and 2, the master cylinder 1 is used for the brake system 22 of this example. In the tandem master cylinder section 2 of the master cylinder 1, the primary hydraulic chamber 9 communicates with one system of brake cylinders 23 and 24, and the secondary hydraulic chamber 10 communicates with the other system of brake cylinders 25 and 26. Communicate.
A brake pedal 27 is connected to the input shaft 4. When the driver depresses the brake pedal 27, the input shaft 4 moves forward.

  Further, the pedal feel simulator unit 3 that is a stroke simulator of the master cylinder 1 has an auxiliary power unit 28 that assists the operating force of the input shaft 4. The auxiliary power unit 28 in this example includes an electromagnet 29 fixed to the partition wall 1 b of the housing 1 a of the master cylinder 1 and a permanent magnet 30 disposed on the simulator operating piston 14. The permanent magnet 30 is an S-pole magnet and is disposed on the simulator operating piston 14 located in the simulator operating hydraulic chamber 15.

  At the time of the forward stroke of the input shaft 4, the attraction force acts between the electromagnet 29 and the permanent magnet 30 by exciting the electromagnet 29 to the S pole of the permanent magnet 30 and the N pole of a different polarity. Then, the simulator operating piston 14 is assisted by the auxiliary power by the suction force to assist the forward stroke operation. Thereby, the forward stroke operation of the input shaft 4 is assisted by the auxiliary power by the electromagnet 29 and the permanent magnet 30 during the forward stroke of the input shaft 4. Therefore, the input shaft 4 is moved forward by a small initial input. That is, the brake pedal 27 is depressed by an initial small brake pedal depression force.

  Further, the repulsive force acts between the electromagnet 29 and the permanent magnet 30 by exciting the electromagnet 29 to the S pole having the same polarity as the S pole of the permanent magnet 30 during the backward (return) stroke of the input shaft 4. Then, the assisting power by the repulsive force is applied to the simulator operating piston 14 to assist the reverse stroke operation. Thereby, the reverse stroke operation of the input shaft 4 is assisted by the auxiliary power by the electromagnet 29 and the permanent magnet 30 during the reverse stroke of the input shaft 4. Therefore, the input shaft 4 is operated to move backward with a small backward force. That is, the brake pedal 27 returns smoothly and reliably.

Thus, when the forward stroke of the input shaft 4 starts, the attractive force between the electromagnet 29 and the permanent magnet 30 acts on the simulator operating piston 14 as auxiliary power, so that the operation start load of the pedal sensation simulator unit 3 is as shown in FIG. It reduces from the operation | movement start load of the conventional pedal feeling simulator part 3 shown in these. Further, the attractive force between the electromagnet 29 and the permanent magnet 30 acts on the simulator operating piston 14 as auxiliary power during the forward stroke of the input shaft 4, so that the operating load of the pedal feeling simulator unit 3 is shown in FIG. 5. The operating load of the conventional pedal feel simulator unit 3 is reduced.

  As shown in FIG. 1, the brake system 22 of this example further includes a power source 32, an electromagnetic switching valve 33, and a control unit (ECU) 34. The power source 32 supplies hydraulic fluid to the power chamber 13. Further, as shown in FIG. 3, the ECU 34 has an electromagnetic switching valve switching setting unit 35 and a magnetic pole setting unit 36. Further, the stroke sensor 5 is connected to the electromagnetic switching valve switching setting unit 35 and the magnetic pole setting unit 36 of the ECU 34. Further, an electromagnetic switching valve 33 is connected to the electromagnetic switching valve switching setting unit 35, and an electromagnet 29 and a power source 37 are connected to the magnetic pole setting unit 36, respectively.

  The ECU 34 receives the stroke signal of the simulator operating piston 14 detected by the stroke sensor 5 (that is, the stroke signal of the input shaft 4 and the depression stroke signal of the brake pedal 27). When the electromagnetic switching valve switching setting unit 35 of the ECU 34 determines that there is no stroke signal from the stroke sensor 5, the electromagnetic switching valve 33 is not operated. As a result, the power chamber 13 is disconnected from the power source 32 and communicated with the reservoir 6. When the electromagnetic switching valve switching setting unit 35 of the ECU 34 determines that the stroke signal from the stroke sensor 5 is a forward stroke signal, the power chamber 13 is disconnected from the reservoir 6 and communicated with the power source 32. The electromagnetic switching valve 33 is switched. Further, when the electromagnetic switching valve switching setting unit 35 of the ECU 34 determines that the pedal depression stroke has stopped after the brake pedal 27 is depressed, the power chamber 13 is shut off from both the power source 32 and the reservoir 6. Thus, the electromagnetic switching valve 33 is switched. Further, when the electromagnetic switching valve switching setting unit 35 of the ECU 34 determines that the stroke signal from the stroke sensor 5 is a reverse stroke signal, the power chamber 13 is disconnected from the power source 32 and communicated with the reservoir 6. The electromagnetic switching valve 33 is switched.

On the other hand, in the brake system 22 of this example, the magnetic pole of the electromagnet 29 is set to the N pole during the forward stroke of the input shaft 4 as an example, and set to the S pole during the return stroke of the input shaft 4. In this case, the electromagnet 29 is de-energized when the input shaft 4 is not stroked and is in the non-operating position, and when the stroke is stopped during the forward stroke of the input shaft 4, the electromagnet 29 becomes the magnetic pole at the time of stop, that is, the N pole In addition, when the stroke is stopped during the return stroke of the input shaft 4, it is held at the magnetic pole at the time of stop, that is, the S pole. The setting of the magnetic poles of the electromagnet 29 is not limited to this, and can be set arbitrarily. Hereinafter, in the description of the brake system 22 of this example, it is assumed that the magnet 29 has a magnetic pole set as described above.
That is, when the magnetic pole setting unit 36 of the ECU 34 determines that there is no stroke signal from the stroke sensor 5 (the stroke signal is 0; the input shaft 4 is inactive; the brake pedal 27 is not depressed), the electromagnet 29 is cut off from the power source 37 and the electromagnet 29 is not energized (power supply). Therefore, the electromagnet 29 is set to non-excitation. When the magnetic pole setting unit 36 of the ECU 34 determines that the stroke signal from the stroke sensor 5 is a forward stroke signal, the electromagnet 29 is connected to the power source 37 so that the electromagnet 29 is excited to the N pole. (Power supply). Further, when the magnetic pole setting unit 36 of the ECU 34 determines that the stroke signal from the stroke sensor 5 is a return stroke signal, the electromagnet 29 is connected to the power source 37 so that the electromagnet 29 is excited to the S pole. To do. Further, the magnetic pole setting unit 36 of the ECU 34 is held at a constant value and does not change after the stroke signal is output from the stroke sensor 5 (that is, the input shaft 4 is in a state where the stroke is stopped during the forward stroke). When the determination is made, the magnetic pole of the electromagnet 29 is held at the magnetic pole at that time, that is, the N pole.

Next, energization control of the electromagnet of the stroke simulator of this example will be described. FIG. 4 is a diagram showing a flow for performing energization control of the electromagnet.
As shown in FIG. 4, it is determined in step S1 whether or not the brake pedal 27 has been depressed. When it is determined that the brake pedal 27 is not depressed, the energization control of the electromagnet ends. That is, when the input shaft 4b of the master cylinder 1 is not operated (no stroke), the necessary power is not supplied to the electromagnet 29 (not energized), and the electromagnet 29 is not excited. If it is determined in step S1 that the brake pedal 27 has been depressed (that is, the input shaft 4b has moved forward), in step S2, the necessary power is supplied (energized) to the electromagnet 29 by the depression stroke of the brake pedal 27. The electromagnet 29 is excited to the N pole. Therefore, an attractive force is generated between the electromagnet 29 and the permanent magnet 30. Next, in step S3, it is determined whether or not the depression stroke of the brake pedal 27 has been stopped. If it is determined that the depression stroke of the brake pedal 27 is not stopped, the process of step S3 is repeated. At this time, the magnetic pole of the electromagnet 29 is held at the N pole.

  Since the stroke signal is held at a constant value from the stroke sensor 5 in step S3 and does not change, it is determined that the brake pedal 27 is depressed and the stroke is stopped (that is, the input shaft 4b is stopped during the forward stroke). The brake pedal 27 is held at the depressed position at that time, and in step S4, the electromagnet 29 is held at the magnetic pole when the stroke is stopped, that is, the N pole. Next, in step S5, it is determined whether or not the brake pedal 27 has stroked. If it is determined that the brake pedal 27 does not make a stroke, the process of step S5 is repeated. At this time, the electromagnet 29 is still held at the N pole. If it is determined in step S5 that the brake pedal 27 has stroked, it is determined in step S6 whether or not the stroke of the brake pedal 27 is a return stroke. If it is determined that the stroke of the brake pedal 27 is not a return stroke, that is, it is determined that the stroke is a depression stroke, the process proceeds to step S3, and the processes after step S3 are repeated. Therefore, the magnetic pole of the electromagnet 29 is held at the N pole.

  If it is determined in step S6 that the stroke of the brake pedal 27 is a return stroke, it is determined in step S7 whether or not the return stroke amount is equal to or greater than a predetermined amount. If it is determined that the return stroke amount is not greater than or equal to the predetermined amount, the process of step S7 is repeated. If it is determined in step S7 that the return stroke amount is greater than or equal to the predetermined amount, the power required for the electromagnet 29 is supplied by the return stroke of the brake pedal 27 in step S8, and the electromagnet 29 is excited to the S pole. Therefore, a repulsive force is generated between the electromagnet 29 and the permanent magnet 30.

  Next, in step S9, it is determined whether or not the return stroke of the brake pedal 27 has stopped. If it is determined that the return stroke of the brake pedal 27 is not stopped, the process of step S9 is repeated. At this time, the magnetic pole of the electromagnet 29 is held at the S pole. If it is determined in step S9 that the return stroke of the brake pedal 27 has been stopped (that is, the input shaft 4b has stopped during the return stroke), the brake pedal 27 is held at the depressed position at that time, and the step In S10, the electromagnet 29 is held at the magnetic pole when the stroke is stopped, that is, the S pole. Next, in step S11, it is determined whether or not the brake pedal 27 has stroked. If it is determined that the brake pedal 27 does not make a stroke, the process of step S11 is repeated. At this time, the electromagnet 29 is still held at the south pole. If it is determined in step S11 that the brake pedal 27 has stroked, it is determined in step S12 whether or not the stroke of the brake pedal 27 is a return stroke. If it is determined that the stroke of the brake pedal 27 is not a return stroke, that is, it is determined that the stroke is a depression stroke, the process proceeds to step S2, and the processes after step S2 are repeated. Therefore, the electromagnet 29 is excited to the N pole.

If it is determined in step S12 that the stroke of the brake pedal 27 is a return stroke, it is determined in step S13 whether or not the return stroke of the brake pedal 27 has stopped. If it is determined that the return stroke of the brake pedal 27 has been stopped, the process proceeds to step S11, and each process subsequent to the process in step S11 is performed. If it is determined in step S13 that the return stroke of the brake pedal 27 has not been stopped, it is determined in step S14 whether or not the return stroke of the brake pedal 27 has ended, that is, the stroke signal of the brake pedal 27 is zero. It is determined whether or not there is. When it is determined that the return stroke of the brake pedal 27 is completed, that is, the stroke signal of the brake pedal 27 is 0, no power is supplied to the electromagnet 29 in step S15, and the electromagnet 29 is set to non-excitation. Thus, the energization control of the electromagnet 29 in the pedal sensation simulator unit 3 of this example is completed.

  According to the pedal sensation simulator unit 3, the master cylinder 1 having the pedal sensation unit 3, and the brake system 22 in this example, the simulator operation piston 14 is attracted by the electromagnet 29 of the auxiliary power unit 28 at least when the operation of the pedal sensation simulator unit 3 is started. Thus, auxiliary power is applied to the simulator operating piston 14 in its operating direction. Therefore, even if the simulator operating piston 14 is operated while bending each of the springs 16, 19, 21 described above, the force at which the simulator operating piston 14 starts operating is reduced at the start of the operation of the pedal sensation simulator unit 3. Can do. As a result, when the operation of the pedal sensation simulator unit 3 is started, the input shaft 4 can be moved forward (operated) with a smaller input. As a result, the brake pedal 27 can be depressed with a smaller pedal depression force, and the operation of the stroke simulation function of the pedal feel simulator unit 3 can be started more smoothly.

  Further, during the forward stroke of the input shaft 4 and the backward stroke of the input shaft 4, the amount of energization to the electromagnet 29 is controlled to appropriately control the attractive force and the repulsive force between the electromagnet 29 and the permanent magnet 30. The pedal feeling simulator unit 3 can have hysteresis. In that case, since energization control with respect to the electromagnet 29 can be performed easily, desired hysteresis can be obtained easily. Further, by controlling the energization amount to the electromagnet 29, the input of the input shaft 4, that is, the pedaling force can be made variable. Thereby, the setting of the pedal depression force of the brake pedal 27 can be flexibly dealt with according to the user's request.

  Further, the pedal feeling simulator cartridge 17 of the pedal feeling simulator unit 3 is abolished, the simulator operating hydraulic pressure chamber 15 is changed to the atmospheric chamber, and the simulator operating piston 14 is moved to the primary piston 7 by the attractive force between the electromagnet 29 and the permanent magnet 30. It is possible to exert an automatic brake function that automatically activates the brake when necessary and a brake assist (BA) function that assists the braking force when necessary.

  The present invention is not limited to the above examples, and various design changes are possible. For example, in the above-described example, the S-pole permanent magnet 30 is disposed on the simulator operating piston 14, but the N-pole permanent magnet 30 may be disposed on the simulator operating piston 14. In this case, contrary to the above example, the electromagnet 29 is excited to the S pole at least when the input shaft 4 starts the forward stroke and is excited to the S pole when the input shaft 4 starts the backward stroke. In the above example, the electromagnet 29 is excited to the N pole in all the forward strokes of the input shaft 4. However, the electromagnet 29 can be excited to the N pole only at the start of the forward stroke of the input shaft 4. Further, the auxiliary power unit 28 may be any auxiliary power unit as long as it can apply auxiliary power to the input shaft 4 in the forward direction at least when the input shaft 4 starts to move forward. In short, the present invention is described in the claims, and various design changes can be made within the scope of the matters.

  A stroke simulator, a master cylinder, and a brake system according to the present invention are respectively a stroke simulator that generates a reaction force simulated according to depression of a pedal, a master cylinder having the stroke simulator, and a brake using the master cylinder. It can be suitably used for the system.

DESCRIPTION OF SYMBOLS 1 ... Master cylinder, 2 ... Tandem master cylinder part, 3 ... Pedal feeling simulator part (stroke simulator), 4 ... Input shaft, 5 ... Stroke sensor, 6 ... Reservoir tank, 7 ... Primary piston, 8 ... Secondary piston, 13 ... Power chamber, 14 ... Simulator operating piston, 15 ... Simulator operating hydraulic chamber, 16 ... Simulator operating piston return spring, 17 ... Pedal sensation simulator cartridge, 18 ... First reaction force simulator piston, 19 ... First reaction force simulator spring, DESCRIPTION OF SYMBOLS 20 ... 2nd reaction force simulator piston, 21 ... 2nd reaction force simulator spring, 22 ... Brake system, 23, 24, 25, 26 ... Brake cylinder, 27 ... Brake pedal, 28 ... Auxiliary power part, 29 ... Electromagnet, 30 ... permanent magnets, 32 ... power , 33 ... electromagnetic switching valve, 34 ... control unit (ECU), 35 ... electromagnetic switching valve switching setting unit, 36 ... magnetic pole setter

Claims (6)

An input shaft that is actuated by input, and
A simulator actuated piston actuated by the input shaft;
A simulator actuated piston return spring that biases the simulator actuated piston in the direction of the non-actuated position;
A reaction force simulator member that outputs a reaction force based on an input of the input shaft to the simulator operation piston by the operation of the simulator operation piston;
A stroke simulator comprising: an auxiliary power unit that applies at least auxiliary power to the simulator operating piston in the operating direction of the simulator operating piston at the start of operation of the input shaft. A controller for controlling energization of the electromagnet;
The auxiliary power unit includes an electromagnet disposed in a housing and a magnet disposed in the simulator operating piston and excited by one of the N pole and the S pole.
The control unit controls energization of the electromagnet so that the electromagnet is excited by the other magnetic pole of the N pole and the S pole at least when the input shaft starts to operate. The stroke simulator according to claim 1, wherein the auxiliary power is applied to the simulator operating piston by a suction force therebetween.   The auxiliary power unit applies auxiliary power to the simulator operating piston in the forward direction of the simulator operating piston during the forward stroke of the input shaft, and operates the simulator in the simulator operating piston during the backward stroke of the input shaft. The stroke simulator according to claim 1, wherein the stroke simulator is applied in a backward direction of the piston. A controller for controlling energization of the electromagnet;
The auxiliary power unit includes an electromagnet disposed in a housing and a magnet disposed in the simulator operating piston and excited by one of the N pole and the S pole.
The auxiliary power unit controls the energization of the electromagnet by controlling the energization of the electromagnet so that the electromagnet is excited by either the N pole or the S pole at least when the input shaft starts operating. The auxiliary power is applied to the simulator operating piston by the attractive force between the magnet and the magnet,
The auxiliary power is controlled by energizing the electromagnet so that the electromagnet is excited by the same magnetic pole as the magnetic pole of the magnet disposed on the simulator operating piston during the reverse stroke of the input shaft. The stroke simulator according to claim 3, wherein the portion applies the auxiliary power to the simulator operating piston by a repulsive force between the electromagnet and the magnet. In a master cylinder having a stroke simulator that outputs a reaction force based on an input of an input shaft and a master cylinder piston that generates a hydraulic pressure based on the input of the input shaft,
5. The master cylinder according to claim 1, wherein the stroke simulator is a stroke simulator according to claim 1. A brake cylinder, a master cylinder that operates when the brake pedal is depressed and generates a brake fluid pressure based on the depression of the brake pedal, and a brake cylinder that generates a brake force with the brake fluid pressure generated in the master cylinder A brake system comprising:
The brake system according to claim 5, wherein the master cylinder is the master cylinder according to claim 5.

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