brake pressure sensor

Abstract

The present application relates to a brake pressure sensor. A brake pressure sensor may include: a housing; an induction portion installed in one end of the housing and configured to guide oil; a regulating portion embedded in the housing and configured to guide oil and adjust the amount of oil passing through the regulating portion as the spacing between the regulating portion and the induction portion changes when the regulating portion moves according to hydraulic pressure; a support portion installed in the other end of the housing and configured to support the regulating portion and guide oil that has passed through the regulating portion; and a measuring portion connected to the support portion and configured to measure the pressure of the oil that has passed through the support portion. The brake pressure sensor makes it possible to improve measurement accuracy at medium / low pressures and stably measure the maximum required brake pressure.

Description

Technical Field

[0001] Exemplary embodiments of the present disclosure relate to a brake pressure sensor, and more particularly, to a brake pressure sensor capable of improving accuracy in a medium / low pressure region and inducing stiffness not exceeding a stiffness limit due to a change in an output value in a high pressure region. Background Art

[0002] Typically, a vehicle includes a braking system for decelerating or braking the vehicle. The braking system includes a pedal that transmits a user's operating force, a booster and a master cylinder connected to the pedal to generate brake hydraulic pressure, and wheel brakes that brake the vehicle's wheels according to the brake hydraulic pressure input from the booster and master cylinder.

[0003] This braking system generates braking force when the driver steps on the brake pedal. At this time, when the braking pressure is greater than the braking pressure under road conditions or the friction force of the wheel brakes generated by the braking pressure is greater than the braking force generated by the tires or the road surface, skidding occurs when the tires slide on the road surface.

[0004] In this state where the brakes are operated, the steering device is locked so that the vehicle cannot be steered in a desired direction.

[0005] Therefore, according to the related art, an ABS (Anti-lock Braking System) has been developed, which electronically controls the pedal force of a brake so as to enable steering when skidding occurs.

[0006] ABS includes a hydraulic unit and an ECU (Electronic Control Unit). The hydraulic unit includes a low-pressure accumulator, a high-pressure accumulator, and multiple solenoid valves for regulating the brake pressure transmitted to the wheel brakes, and the ECU is used to control the components that perform electronic operations.

[0007] The hydraulic unit also includes a pressure sensor that senses the brake operating pressure generated by the master cylinder, which is proportional to the brake pedal force, and transmits the sensed brake operating pressure to the ECU as an electrical signal. The ECU controls the operation of the brakes based on the electrical signal transmitted from the pressure sensor.

[0008] More specifically, a pressure sensor is installed in a machined hole formed at the front end of the master cylinder and is electrically connected to the ECU's circuit board via a separate connector and cable. This pressure sensor transmits an output signal having a magnitude proportional to the measured pressure.

[0009] Under operating conditions requiring high braking forces and sudden braking associated with high-pressure areas, pressure sensors require rigidity over a wide measurement range to achieve high output accuracy. However, due to limited output sources, when a wide range is uniformly set, the pressure variation of each output signal becomes so great that accuracy is reduced.

[0010] In addition, the braking area related to the low pressure area is used in the medium / low pressure area, and the autonomous vehicle requires low-pressure precise control, so every small signal of pressure change is required.

[0011] That is, it is difficult for conventional pressure sensors to simultaneously meet the conflicting requirements for brake control in the high-pressure region and the low-pressure region. Therefore, a device that can solve this problem is needed.

[0012] A related art of the present disclosure is disclosed in Korean Patent No. 10-0609026, registered on July 27, 2006, and entitled “Brake Oil Pressure Control System with Pressure Sensor.” Summary of the Invention

[0013] Various embodiments are directed to a brake pressure sensor capable of improving accuracy in a medium / low pressure region and inducing stiffness that does not exceed a stiffness limit due to a change in an output value in a high pressure region.

[0014] In an embodiment, the brake pressure sensor may include: a housing portion; an inducing portion installed in one end portion of the housing portion and configured to guide oil; a regulating portion embedded in the housing portion and configured to guide oil and adjust the amount of oil passing through the regulating portion as the interval between the regulating portion and the inducing portion changes when the regulating portion moves according to the hydraulic pressure; a supporting portion installed in the other end portion of the housing portion and configured to support the regulating portion and guide the oil that has passed through the regulating portion; and a measuring portion connected to the supporting portion and configured to measure the pressure of the oil that has passed through the supporting portion.

[0015] The shell part may include: a first shell part, into which the inducing part is inserted; a second shell part, which protrudes from the interior of the first shell part and is configured to support the inducing part; a third shell part, which protrudes from the interior of the first shell part and is configured to support the adjusting part; and a fourth shell part, which extends from the end of the first shell part, has an inner diameter larger than that of the first shell part, and has the supporting part installed in the fourth shell part.

[0016] The induction portion may include: an induction body which is inserted into the housing portion; one or more induction retainers which extend from the induction body and are in close contact with the inner circumferential surface of the housing portion; and an induction ball which is formed in the induction body and has a spherical shape to induce oil that has passed through the induction retainers.

[0017] The regulating portion may include: a first regulating portion supported by the housing portion and configured to guide oil to the interior of the first regulating portion and adjust the amount of oil guided through the gap with the inducing portion; a second regulating portion extending from the first regulating portion, configured to guide oil to the interior of the second regulating portion, and supported by the supporting portion; a third regulating portion protruding from the exterior of the second regulating portion; and a fourth regulating portion disposed between the third regulating portion and the housing portion and configured to elastically support the third regulating portion.

[0018] When the first operating force applied to the first regulating portion is denoted by F1 , the spring force of the fourth regulating portion is denoted by F3 , and the second operating force applied to the second regulating portion is denoted by F2 , a relationship of F1 + F3 = F2 may be established.

[0019] The node may be changed according to an area of ​​an input portion of the first regulating portion, an area of ​​an output portion of the second regulating portion, or a spring constant of the fourth regulating portion.

[0020] The support portion may include: a first support portion embedded in the housing portion; a second support portion protruding inwardly from the first support portion and configured to support the outside of the adjusting portion; a third support portion extending from the first support portion and configured to support an end of the adjusting portion; a fourth support portion extending from the third support portion and connected to the end of the housing portion; and a fifth support portion configured to connect the fourth support portion and the measuring portion and configured to guide oil.

[0021] The second support portion may have a sealing portion formed thereon and configured to prevent oil leakage.

[0022] The first supporting portion, the second supporting portion, the third supporting portion, the fourth supporting portion, and the fifth supporting portion may be formed into one body.

[0023] The first supporting portion, the second supporting portion, the third supporting portion, and the fourth supporting portion may be formed as one body, and the fifth supporting portion may be manufactured as a separate component.

[0024] In the brake pressure sensor according to an embodiment of the present disclosure, the flow rate can be adjusted as the adjustment portion embedded in the housing portion moves by the force applied to the input portion and the output portion, which makes it possible to improve the measurement accuracy at medium / low pressures and stably measure the maximum required brake pressure. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 is a diagram schematically illustrating a brake pressure sensor according to an embodiment of the present disclosure.

[0026] Figure 2 2 is a diagram schematically illustrating a housing portion according to an embodiment of the present disclosure.

[0027] Figure 3 2 is a diagram schematically illustrating an induction portion according to an embodiment of the present disclosure.

[0028] Figure 4 2 is a diagram schematically illustrating an adjustment portion according to an embodiment of the present disclosure.

[0029] Figure 5 is a graph schematically illustrating an output signal of a brake pressure sensor according to an embodiment of the present disclosure.

[0030] Figure 6 is a diagram schematically illustrating a support portion according to an embodiment of the present disclosure. DETAILED DESCRIPTION

[0031] Hereinafter, a brake pressure sensor will be described using various exemplary embodiments with reference to the accompanying drawings. It should be noted that the drawings are not drawn to exact scale and that the thickness of lines or the dimensions of components may be exaggerated for ease of description and clarity. Furthermore, the terms used herein are defined with the functionality of the present invention in mind and may vary depending on the user's or operator's preferences or intentions. Therefore, term definitions should be made in light of the overall disclosure set forth herein.

[0032] Figure 1 Schematically shows a brake pressure sensor 1 according to an embodiment of the present disclosure. Figure 1 The brake pressure sensor 1 according to the embodiment of the present disclosure includes a housing portion 10, an induction portion 20, an adjustment portion 30, a support portion 40, and a measurement portion 50. These components can be assembled by various methods such as interference fitting, bolting, threading, and welding.

[0033] The housing portion 10 can be connected to the master cylinder and guide oil to measure the hydraulic pressure of the master cylinder. The housing portion 10 can be directly connected to various targets whose hydraulic pressure needs to be measured and has a shape for guiding oil stored in the target.

[0034] The induction portion 20 is mounted at one end of the housing portion 10 and is used to guide the oil. For example, the induction portion 20 may be provided at the inlet of the housing portion 10 into which the oil is introduced. The induction portion 20 may guide the oil introduced into the housing portion 10 and adjust the amount of the oil according to the distance from the regulating portion 30.

[0035] The regulating portion 30 may be embedded in the housing portion 10 and is used to guide oil. As the regulating portion 30 moves in response to hydraulic pressure, the gap between the regulating portion 30 and the inducing portion 20 may change, thereby adjusting the amount of oil passing through the regulating portion 30. For example, the gap between the inducing portion 20 and the regulating portion 30 may be adjusted by the force of the oil applied to the input portion of the regulating portion 30, the force of the oil applied to the output portion of the regulating portion 30, and the force of a spring elastically supporting the regulating portion 30. Oil can flow through the regulating portion 30.

[0036] The support portion 40 is installed at the other end portion of the housing portion 10 , and serves to support the regulating portion 30 and guide the oil having passed through the regulating portion 30 .

[0037] The measuring portion 50 connected to the support portion 40 is used to measure the pressure of the oil that has passed through the support portion 40 .

[0038] Figure 2 Schematically illustrates a housing portion according to an embodiment of the present disclosure. Figure 2 The housing portion 10 according to the embodiment of the present disclosure includes a first housing portion 11 , a second housing portion 12 , a third housing portion 13 and a fourth housing portion 14 .

[0039] The induction portion 20 is inserted into the first housing portion 11. For example, the first housing portion 11 may have an end connected to the master cylinder, and the interior of the first housing portion 11 may have a tubular shape to guide oil through the first housing portion.

[0040] The second housing portion 12 protrudes from the inside of the first housing portion 11 and serves to support the inducing portion 20. For example, the inducing portion 20 inserted into the first housing portion 11 may be locked to the second housing portion 12 so that its insertion position is fixed.

[0041] The third housing portion 13 protrudes from the interior of the first housing portion 11 and serves to support the adjustment portion 30. For example, the second housing portion 12 and the third housing portion 13 may be sequentially disposed between one end portion of the first housing portion 11, into which oil is initially introduced, and the other end portion of the first housing portion 11. The third housing portion 13 may be formed to surround the outer peripheral surface of the adjustment portion 30 so that oil can pass only through the interior of the adjustment portion 30.

[0042] The fourth housing portion 14 extends from the end of the first housing portion 11 and has a larger inner diameter than the first housing portion 11, and the support portion 40 is installed in the fourth housing portion 14. For example, the fourth housing portion 14 may be designed to have larger inner and outer diameters than the first housing portion 11.

[0043] Figure 3 Schematically illustrates an induction portion according to an embodiment of the present disclosure. Figure 3The induction portion 20 according to the embodiment of the present disclosure includes an induction body 21 , an induction holder 22 and an induction ball 23 .

[0044] The inducing body 21 is inserted into the housing portion 10. For example, the inducing body 21 may be inserted into the first housing portion 11 and supported by the master cylinder.

[0045] One or more induction fixtures 22 extend from the induction body 21 and are in close contact with the inner circumferential surface of the housing portion 10. For example, a plurality of induction fixtures 22 may be arranged spaced apart from each other along the circumference of the induction body 21 and locked to the second housing portion 12 so as to restrict the induction body 21 from moving in one direction. Oil may pass between the induction fixtures 22. An O-ring may be provided in the space between the induction fixture 22 and the third housing portion 13 and used to prevent oil leakage. The induction fixture 22 may be threaded or press-fitted into the first housing portion 11. In addition, the state in which the induction fixture 22 is installed in the first housing portion 11 may be maintained by various other methods.

[0046] The induction ball 23 is formed in the induction body 21 and serves to guide the oil that has passed through the induction retainer 22. This induction ball 23 has a spherical shape. For example, one surface of the induction body 21 may face the master cylinder, and the induction ball 23 may be formed on the other surface of the induction body 21. The induction ball 23 may be formed in the center portion of the induction body 21, and the induction retainer 22 may be disposed around the induction ball 23.

[0047] Figure 4 is a diagram schematically showing an adjustment portion according to an embodiment of the present disclosure, Figure 5 : is a graph schematically showing an output signal of a brake pressure sensor according to an embodiment of the present disclosure. Figure 4 and Figure 5 , the adjustment portion 30 according to the embodiment of the present disclosure includes a first adjustment portion 31 , a second adjustment portion 32 , a third adjustment portion 33 and a fourth adjustment portion 34 .

[0048] The first regulating portion 31 is supported by the housing portion 10 and is used to guide oil into the interior of the first regulating portion. The amount of oil guided thereto is adjusted by the spacing from the induction portion 20. For example, the first regulating portion 31 may have a tubular shape to guide the oil, penetrate the third housing portion 13, and have an end formed to cover the induction ball 23. The oil can move into the first regulating portion 31 through the space between the first regulating portion 31 and the induction ball 23. When the first regulating portion 31 moves and comes into close contact with the induction ball 23, the oil is prevented from moving into the first regulating portion 31.

[0049] The second regulating portion 32 extends from the first regulating portion 31 for guiding oil therein and is supported by the support portion 40. For example, the second regulating portion 32 may be designed to have the same inner diameter as the first regulating portion 31 and a larger outer diameter than the first regulating portion 31.

[0050] The third regulating portion 33 protrudes from the outside of the second regulating portion 32. For example, the third regulating portion 33 may be provided along the circumferential direction of the second regulating portion 32, locked to the support portion 40, and restricted from moving toward the measuring portion 50.

[0051] The fourth regulating portion 34 is provided between the third regulating portion 33 and the housing portion 10 and serves to elastically support the third regulating portion 33. For example, the fourth regulating portion 34 may be formed in the shape of a coil spring wound around the second regulating portion 32. The fourth regulating portion 34 may have one end supported by the third housing portion 13 and the other end supported by the third regulating portion 33.

[0052] When the first operating force applied to the first regulating portion 31 is denoted by F1 , the spring force of the fourth regulating portion 34 is denoted by F3 , and the second operating force applied to the second regulating portion 32 is denoted by F2 , a relationship of F1 + F3 = F2 may be established.

[0053] In this case, the first operating force F1 may refer to a force applied to the first regulating portion 31 by the hydraulic pressure introduced through the first regulating portion 31 and may be determined by the first hydraulic pressure P1 input from the first regulating portion 31 and the input portion area A1 of the first regulating portion 31 .

[0054] The second operating force F2 may represent a force applied to the second regulating portion 32 by the hydraulic pressure discharged through the second regulating portion 32 and may be determined by the second hydraulic pressure P2 discharged from the second regulating portion 32 and an output portion area A2 of the second regulating portion 32 .

[0055] The node can be changed according to the input area A1 of the first adjustment part 31, the output area A2 or the spring constant of the second adjustment part 32. According to the design, the input area A1 can be adjusted to improve the output resolution in the medium / low pressure area. According to the design, the output area A2 can be adjusted to improve the output resolution in the medium / low pressure area. According to the design, the spring constant can be adjusted to improve the output resolution in the medium / low pressure area. According to the design, the input area A1 and the output area A2 can be adjusted to improve the output resolution in the medium / low pressure area. According to the design, the input area A1 and the spring constant can be adjusted to improve the output resolution in the medium / low pressure area. According to the design, the output area A2 and the spring constant can be adjusted to improve the output resolution in the medium / low pressure area. According to the design, the input area A1, the output area A2 and the spring constant can be adjusted to improve the output resolution in the medium / low pressure area.

[0056] That is to say, Figure 5 The graph shows that in the medium / low pressure region, the medium / low pressure line (b) has a greater slope than the general brake output line (a). Therefore, the output signal change per unit signal is greater than the input value, which allows for more accurate measurement.

[0057] In the high-pressure region after node (d), the slope of high-pressure line (c) is smaller than that of general brake output line (a). That is, since the flow rate is adjusted by the adjustment unit 30, the measurement unit 50 can stably measure the maximum required brake pressure.

[0058] Figure 6 Schematically illustrates a support portion according to an embodiment of the present disclosure. Figure 6 The support portion 40 according to the embodiment of the present disclosure includes a first support portion 41 , a second support portion 42 , a third support portion 43 , a fourth support portion 44 and a fifth support portion 45 .

[0059] The first support portion 41 is embedded in the housing portion 10. For example, the first support portion 41 may be inserted into the fourth housing portion 14 and in close contact with the inner circumferential surface of the fourth housing portion 14. The first support portion 41 may be designed to have an inner circumferential surface larger than the outer diameter of the second adjustment portion 32, thereby forming an operating space between the first support portion and the second adjustment portion.

[0060] The second support portion 42 protrudes inward from the first support portion 41 and is used to support the outside of the adjustment portion 30. For example, the second support portion 42 can be provided on the movement path of the third adjustment portion 33 and restrict the third adjustment portion 33 from moving in one direction.

[0061] The third support portion 43 extends from the first support portion 41 and supports the end of the adjustment portion 30. For example, the third support portion 43 may be formed as a circle surrounding the end of the second adjustment portion 32 to support the movable second adjustment portion 32. The third support portion 43 and the second support portion 42 may limit the movement of the adjustment portion 30 in one direction. The seal portion 49 provided on the second support portion 42 may be in close contact with the outer peripheral surface of the second adjustment portion 32 to prevent oil leakage.

[0062] The fourth support portion 44 extends from the third support portion 43 and is coupled to the end of the housing portion 10. For example, the fourth support portion 44 may be screwed to the inner circumferential surface of the fourth housing portion 14 and locked to the end of the fourth housing portion 14, thereby limiting the insertion depth of the fourth support portion.

[0063] The fifth support portion 45 is used to connect the fourth support portion 44 and the measuring portion 50 and guide the oil. For example, the fifth support portion 45 may have a shape through which the oil can move.

[0064] The first support portion 41, the second support portion 42, the third support portion 43, and the fourth support portion 44 may be formed as a single body. The fifth support portion 45 may be formed as a single body with the fourth support portion 44, or may be manufactured as a separate component from the fourth support portion 44. For example, when the first to fifth support portions 41 to 45 are formed as a single body, the support portion 40 may serve as a medium connecting the housing portion 10 and the measuring portion 50. When the fifth support portion 45 is manufactured as a separate component, the fifth support portion 45 may serve as a medium connecting the fourth support portion 44 and the measuring portion 50.

[0065] Hereinafter, an assembling process and operation of the brake pressure sensor having the above-described structure according to an embodiment of the present disclosure will be described as follows.

[0066] The inducing portion 20 is installed in the end portion of the housing portion 10, and the regulating portion 30 supported by the inside of the housing portion 10 is connected to the measuring portion 50 through the supporting portion 40. In this case, the end portion of the housing portion 10 is connected to the master cylinder.

[0067] In the above state, the oil of the master cylinder is introduced into the housing portion 10 and passes through the regulating portion 30 and the support portion 40 via the space between the inducing portion 20 and the regulating portion 30 , and the measuring portion 50 measures the hydraulic pressure.

[0068] The regulating portion 30 includes a first regulating portion 31 , a second regulating portion 32 extending from the first regulating portion 31 , a third regulating portion 33 protruding from an exterior of the second regulating portion 32 , and a fourth regulating portion 34 elastically supporting the third regulating portion 33 .

[0069] The node can be changed according to the input portion area A1 and the output portion area A2 of the adjustment portion 30 and the spring force of the fourth adjustment portion 34 .

[0070] At medium / low pressure, flow rate regulation by the regulating portion 30 is not performed, which makes it possible to improve output resolution.

[0071] Under high pressure, a stronger force may be applied from the output portion of the regulating portion 30, causing the fourth regulating portion 34 to contract and the first regulating portion 31 to approach the inducing portion 20 to adjust the flow rate. Therefore, the measuring portion 50 can stably measure the maximum required brake pressure.

[0072] In the brake pressure sensor 1 according to an embodiment of the present disclosure, as the regulating portion 30 embedded in the housing portion 10 moves by the force applied to the input portion and the output portion, the flow rate can be adjusted, which makes it possible to improve the measurement accuracy at medium / low pressures and stably measure the maximum required brake pressure.

[0073] Although exemplary embodiments of the present disclosure have been disclosed for illustrative purposes, those skilled in the art will appreciate that various modifications, additions and substitutions are possible, without departing from the scope and spirit of the disclosure as defined in the accompanying claims.

Claims

1. A brake pressure sensor, comprising: housing portion; an induction portion installed in one end portion of the housing portion and configured to guide oil; a regulating portion embedded in the housing portion and configured to guide oil and regulate an amount of oil passing through the regulating portion as a spacing between the regulating portion and the inducing portion changes when the regulating portion moves according to hydraulic pressure; a support portion installed in the other end portion of the housing portion and configured to support the adjustment portion and guide oil having passed through the adjustment portion; as well as a measuring portion connected to the support portion and configured to measure a pressure of oil that has passed through the support portion, Wherein, the induction part includes: an induction body, the induction body being inserted into the housing portion; one or more induction fixers extending from the induction body and in close contact with the inner peripheral surface of the housing portion; and An induction ball is formed in the induction body and has a spherical shape to induct the oil having passed through the induction holder.

2. The brake pressure sensor according to claim 1, wherein: The housing portion comprises: a first housing portion, the induction portion being inserted into the first housing portion; a second housing portion protruding from an interior of the first housing portion and configured to support the inducing portion; a third housing portion protruding from an interior of the first housing portion and configured to support the adjustment portion; and A fourth housing portion extends from an end portion of the first housing portion, has an inner diameter larger than that of the first housing portion, and has the support portion mounted therein.

3. The brake pressure sensor according to claim 1, wherein: The support portion includes: a first supporting portion, wherein the first supporting portion is embedded in the housing portion; a second support portion that protrudes inwardly from the first support portion and is configured to support an exterior of the adjustment portion; a third supporting portion extending from the first supporting portion and configured to support an end portion of the adjusting portion; a fourth support portion extending from the third support portion and coupled to an end portion of the housing portion; and A fifth support portion is configured to connect the fourth support portion and the measuring portion and to guide oil.

4. The brake pressure sensor according to claim 3, wherein: The second support portion has a sealing portion formed thereon and configured to prevent oil leakage.

5. The brake pressure sensor according to claim 3, wherein: The first supporting portion, the second supporting portion, the third supporting portion, the fourth supporting portion, and the fifth supporting portion are formed into one body.

6. The brake pressure sensor according to claim 3, wherein: The first supporting portion, the second supporting portion, the third supporting portion, and the fourth supporting portion are formed as one body, and the fifth supporting portion is manufactured as a separate component.

7. A brake pressure sensor, comprising: housing portion; an induction portion installed in one end portion of the housing portion and configured to guide oil; a regulating portion embedded in the housing portion and configured to guide oil and regulate an amount of oil passing through the regulating portion as a spacing between the regulating portion and the inducing portion changes when the regulating portion moves according to hydraulic pressure; a support portion installed in the other end portion of the housing portion and configured to support the adjustment portion and guide oil having passed through the adjustment portion; as well as a measuring portion connected to the support portion and configured to measure a pressure of oil that has passed through the support portion, Wherein, the adjustment unit includes: a first regulating portion supported by the housing portion and configured to guide oil into an interior of the first regulating portion and to adjust an amount of the oil guided through the gap with the inducing portion; a second regulating portion extending from the first regulating portion, configured to guide oil into an interior of the second regulating portion, and supported by the supporting portion; a third regulating portion protruding from an exterior of the second regulating portion; and A fourth adjustment portion is provided between the third adjustment portion and the housing portion and is configured to elastically support the third adjustment portion.

8. The brake pressure sensor according to claim 7, wherein: When a first operating force applied to the first regulating portion is denoted by F1 , a spring force of the fourth regulating portion is denoted by F3 , and a second operating force applied to the second regulating portion is denoted by F2 , a relationship of F1 + F3 = F2 is established.

9. The brake pressure sensor according to claim 8, wherein: The node can be changed according to the area of ​​the input portion of the first adjustment portion, the area of ​​the output portion of the second adjustment portion, or the spring constant of the fourth adjustment portion.

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