JPH01306357A - Anti-lock device - Google Patents

Abstract

PURPOSE:To make a flow-rate control switch-over valve small in structure by forming a flow passage in a spool, which is separated fore and aft by a stationary orifice, constituting one side of the passage to be one part of a mass flow passage, and thereby constituting the other part of the passage to be one pat of a decompression flow passage. CONSTITUTION:A flow-rate control switch-over valve 25 allows a spool 41 which has a flow passage 42 containing a stationary orifice 43 inside, to be slidably engaged within a sleeve 32 one end of which is opened wherein the sleeve is provided with an inlet 34 communicated with a master cylinder 21, No.1 outlet 35 communicated with a wheel brake 23 and No.2 outlet 36 communicated with a discharge flow passage 24. The relative position in the axial direction between the spool 41 and the sleeve 32 allows a mass flow passage which communicates the inlet 34 with No.1 outlet 35 when an anti-lock device is out of action, and also allows the mass flow passage to be closed so as to let a decompression flow passage which communicates No.1 outlet 35 with No.2 outlet 36 be opened, when the anti-lock device is decompressed, that is, when an exhaust valve 26 is opened. This constitution can thereby make the flow-rate control switch-over valve simple in structure.

Description

[Detailed description of the invention]

The present invention relates to an anti-lock device, and more specifically, in a brake stem for an automobile, a wheel speed detector, a vehicle body speed detector, etc. are used to detect the locked state of Q1 wheel, and sudden braking is activated. When the occurrence of excessive slip or its signs is detected, ? [By operating the valve and reducing the brake pressure, the braking force is controlled to the optimum level. 2. Description of the Related Art In the past, various proposals have been made regarding this type of anti-lock device. A normally open inlet valve is provided in the main flow path that communicates between the point ring and the brake fluid storage tank, while a normally closed discharge valve is provided in each of the discharge flow paths that communicate between the point ring and the brake fluid storage tank. Both the inlet valve and the discharge valve are electrically operated in response to a detection signal from the anti-lock detection means. In this device, when the anti-lock is not activated, neither the inlet valve nor the discharge valve is supplied with power, and the hydraulic fluid flows into the wheel nolinder according to the pressure of the brake pedal. In the event of a drip, that is, when reducing the brake fluid pressure, power is supplied to the inlet valve and discharge valve described in 1. The inlet valve closes and the discharge valve opens to return the hydraulic fluid on the pour-no-ring side to the storage tank. , is pumped to the master cylinder side by a pump. In addition, when pressurizing the brake fluid pressure again, the inlet valve is opened and the discharge valve is closed with no power supplied, and when the brake fluid pressure is maintained at a constant pressure, power is supplied only to the inlet valve and the valve is closed. Since the discharge valve is in the closed position, the brake fluid pressure is kept constant. In this way, this device can perform control in three modes: pressure reduction, pressure increase, and constant pressure maintenance, but there are two valves that are operated by power supply, namely:
This method requires an inlet valve and a discharge valve, which has the drawback of increasing the number of parts and the labor involved in installing it, resulting in higher costs. The above-mentioned drawbacks have been solved, and the solenoid valve has been changed to one (('gJ) and the Andiro J device with a simplified configuration is now available for U, S, P4.
1.715,666. This device is not shown in FIG. 3 (IXII), and instead of providing the electromagnetically actuated introduction valve in the main passage 3 that communicates the pressurizing source 1 and the wheel-and-linda 2, a spring 4 and a liquid fluid are provided. A non-electromagnetically actuated three-point, one-two-position switching valve 5 for controlling the flow rate is provided, and a normally closed electromagnetic discharge valve JP7 is provided in the exhaust flow path 6, which is normally closed and is a two-point, two-position switching valve. In this device, the combination of the non-electromagnetic flow control switching valve 5 and the electromagnetic discharge valve 7 performs anti-lock control in two modes of pressure reduction and pressurization only. As shown in the figure, the flow control switching valve 5 has a structure in which a spool 12 is fitted into a sleeve 11 formed in a cylinder block 10 so as to be slidable in the axial direction by biasing a spool 12 with a spring 4. The inlet where the hydraulic fluid from the master cylinder flows into! 3. First outlet 14 for draining the working fluid to the wheel-and-linda, discharge valve 7
The structure is such that second outlets 15 through which the hydraulic fluid flows out to the hydraulic fluid storage tank are provided in a direction perpendicular to the axial direction. Problems to be Solved by the Invention In the flow rate control switching valve of U, S, P, 4,715,666 described above, when there is air (bubbles) in the return spring chamber 17 of the sleeve 11, the pressure of the - Due to the collapse of air bubbles during lifting and lowering, the spool 12 does not move to the anti-lock position, and not only does it become impossible to pressurize, but in that state, the return spring chamber 17 closes to the inlet 13.
is separated by a fixed orifice 19 via a passage 18, and the first outlet 14 is separated by a variable orifice formed by an end face 20 of the spool I2 and a hole 21 in the sleeve via a second outlet 15, so that air bubbles It is difficult to discharge the air, and the structure makes it impossible to bleed air easily. Furthermore, this difficulty in removing air cannot be changed regardless of whether the flow rate control switching valve is oriented either vertically or vertically, or even if an electromagnetically operated discharge valve is operated. In this way, when air remains in the return spring chamber, brake pressure is not generated in the wheel brakes in response to the amount of depression of the brake pedal, resulting in poor brake performance. Furthermore, at least one sleeve of the flow control switching valve must be offset from the open end, which requires an end plug to close the open end, which increases the number of parts and requires time and effort to install, resulting in high costs. There was a drawback that led to Furthermore, during the repressurization process with the solenoid discharge valve closed,
If the leakage m between the spool and sleeve is not suppressed to a sufficiently small level, the excess flow rate from the design protozoa set by the return spring and orifice will flow into the wheel brake, so it is necessary to sufficiently impair the machining accuracy of the spool and sleeve. However, it also had the disadvantage of increasing costs. Means for Solving the Problems The present invention aims to eliminate the above-mentioned drawbacks, and includes providing a discharge flow path branching from the main flow path that communicates the pressurization source and the wheel brake, and providing a flow control system in the branch portion. A switching valve is provided, and a normally closed discharge valve that is opened by electromagnetic operation is provided on the discharge flow path side. within at least six one-way opening sleeves having a second outlet in communication with the
The spool that connects the liquid passage, which includes a fixed orifice inside, is urged by a return spring and fitted so that it can slide freely in the axial direction, and anti-lock is disabled by the relative position of the spool and sleeve in the axial direction. When the pressure source and the wheel brake are connected to each other, a large flow path is opened, and when the anti-lock pressure is reduced, that is, when the exhaust valve is opened, the large flow path is closed and a pressure reduction flow path is opened that connects the wheel brake and the exhaust valve. In addition, during anti-lock repressurization, after the discharge valve is closed, while the pressure difference between the pressure source pressure and the wheel brake pressure horn exceeds a certain value △P, it is determined by the biasing force of the return spring and the cross-sectional area of the spool. A pressure difference is generated before and after a fixed orifice provided inside the spool, and a variable orifice is provided between the pressure source and the wheel brake, which allows only a flow m equal to the flow rate determined by this pressure difference and the area of the orifice to pass through. A small flow path is configured in series with the fixed orifice and communicates the pressure source and the wheel brake via both orifices, and the pressure difference between the pressure source and the wheel brake is gradually reduced by the flow rate, and the pressure difference between the pressure source and the wheel brake is gradually reduced. When the pressure difference decreases to ΔP, the large flow path communicating between the pressurization source and the wheel brakes is closed again and the state returns to the non-operating state. is a hole drilled in the side wall of the sleeve in a direction perpendicular to the axial direction of the sleeve,
One axial end opening of the sleeve is configured as a second outlet to the discharge passage, and the second outlet is in direct communication with the return spring so that the return spring chamber is included in the vacuum passage. At the same time, the electromagnetically actuated discharge valve is installed in series so as to close the opening end of the sleeve on the side where the second outlet is formed, and is fitted into the sleeve and biased by a return spring so as to axially move. In the sliding spool, a liquid passage is formed that passes through the axial direction and is separated from the front and back by an orifice, and one side of the liquid passage constitutes a part of the large flow passage, and the other side constitutes a part of the large passage. provides an anti-lock device constituting a part of the decompression flow path. In addition, the present invention is configured with a small flow path, and when the wheel brake is repressurized with a constant flow, the fixed orifice and! 1 cho 2
The gap between the spool sleeves, which can create a continuous leakage path, is filled with pressure from the pressurizing source and the wheels! It is constructed in such a way that the differential pressure of the NOK pressure is not directly applied. Bait As mentioned above, in this device, the second outlet of the flow rate control switching valve that communicates with the discharge valve is provided on the opening side of one end in the axial direction of the sleeve, and the second outlet is directly communicated with the return spring chamber. Moreover, since one of the liquid passages provided in the spool and separated by an orifice constitutes a part of the pressure reduction passage together with the return spring chamber, the air in the return spring chamber is actuated to open the discharge valve. It can be easily discharged without any problems. Further, since the open end of the sleeve is closed with a discharge valve, an end plug can be made unnecessary. Furthermore, when forming the small flow path, since there is no leak path with a large pressure difference in the gap between the spool and the sleeve in parallel with the fixed orifice, it becomes possible to set the gap between the spool and the sleeve to be slightly larger. The present invention will now be explained in detail with reference to embodiments shown in the drawings. FIG. 1 shows the overall structure of a praxostem equipped with an anti-lock device according to the present invention. Prekipetal 20
The master cylinder 21, which is a pressurization source that operates in response to the depression f, communicates with a wheel brake 23 including a wheel cylinder via a main flow path 22, and a discharge flow path 24 branches from the main flow path 22, and a discharge flow path 24 branches off from the main flow path 22. At the branch position, a non-Tilt magnetic operated flow rate control switching valve 25 and an electromagnetically operated discharge valve 26 are installed in series and combined in one ring block 27. The discharge passage 24 communicates with a known plunger pump 29 via a hydraulic fluid storage tank 28 , and the plunger pump 29 communicates with the master cylinder 21 via a reflux passage 30 . The discharged hydraulic fluid is transferred to the master flinder 2 by the plant pump 29.
It is pumped to the 1st side. To explain in detail the structure of the flow rate control switching valve 25 and the discharge valve 2G provided at the branch point between the main flow path 22 and the discharge flow path 24, a hole 31 is bored in one cylinder tub 27, A sleeve 32 of the flow control switching valve 25 is fitted and fixed in the hole 31, and a discharge valve 26 made of a solenoid valve is installed on the opening side of the hole 31 so as to close the opening. Both ends are open, and one end is fixed to the bottom of the hole 31, while the other end is fixed to the frame 33 of the discharge valve 26.
are connected and fixed. Between the outer circumference of the sleeve 32 and the inner circumference of the hole 31, there is a main channel 22 on the master sill 21 side.
A hydraulic fluid inlet 34 is formed which communicates with the brake device 23 side, and a first outlet 35 of the hydraulic fluid which communicates with the brake device 23 side is formed. A second outlet 36 for the hydraulic fluid communicates linearly with the side. A filter 70 is attached to the inlets 3 and 1 to collect dust from the working fluid flowing in from the master/ringer side. The sleeve 32 is provided with an inlet passage 37 extending in the radial direction and communicating with the inlet 34 from the bottom side, and a first outlet passage 38 and a second outlet passage communicating with the first outlet 35 in the radial direction. 39 are drilled. A spool 41 is fitted into the sleeve 32 so as to be slidable in the axial direction. A first fluid passage 42A and a second fluid passage in the axial direction sandwich an orifice 43 in the axial center of the spool=i1.
A liquid passageway 42r3 is formed. Further, a third liquid passage 44 and a fourth liquid passage 45 are formed which penetrate in the radial direction from the bottom side of the spool 4I and communicate with the first liquid passage 42A. Fifth radial fluid passage 4 in communication
6 is drilled. The third liquid passage 44 is the spool 41
It communicates with and shuts off from the inlet passage 37 and the inlet 34 according to the movement of the inlet, and the open end of the outer surface thereof has a metal edge. The fourth liquid passage 45 and the fifth liquid passage 46 are formed in front and behind with the orifice 43 in between, and the first
The lead-out path 38 and the second lead-out path 39 are opened and closed. The tip of the spool 41 is formed as a spring receiver 47, and the frame 3 communicates with the second outlet 36 of the sleeve 32.
Four return springs are compressed between the spring receiver 48 fixed to the inner surface of the liquid passage 71 of No. 3. A filter 50 is attached to the spring receiver 48 to collect dust from the hydraulic fluid flowing into the fluid passage 71 through a return spring chamber 51 surrounded by the sleeve 32, spool 41, and frame 33. A discharge valve 26 installed to close the open end side of the hole 31
As shown in the figure, the liquid passage 7I communicating with the second outlet 36 on the same axis is formed at the inner end of the axial core of the frame 33, and a fixed valve seat 54 is provided in the liquid passage 7I. The fixed valve seat 54 is opened and closed by a movable valve body 56, which will be described later. In this way, the second outlet 36 formed at the axial opening end of the sleeve 32 of the flow control switching valve 25 is arranged in series in the same direction as the discharge valve 26, and the working fluid is directly supplied from the second outlet 36 to the discharge valve 26. I try to be guided in a straight line. - The frame 33 of the discharge valve 26 is formed with a large-diameter hollow part 52 in the shaft core part communicating with the liquid passage 71 that communicates with the second outlet 36, and the hollow part 52 and the discharge passage are connected to each other. 24 is formed. The above liquid passage 7
1, the fixed valve seat 54 described in 1 is attached, while the hollow part 5
2, the armature 55 is slidably fitted in the axial direction,
The fixed valve seat 54 is opened and closed by a movable valve body 56 fixed to the armadure 55. In the frame 33, a stator 58 is installed at a position facing the armature 55, and a coil 59 is installed at the outer circumferential position of the stator 58.
5 and the movable valve body 56 are operated in the direction of the arrow to open the valve seat 54. Further, a spring 60 is stretched between the armature 55 and the stator 58, and when power is not supplied, the spring 60 is biased to close the valve seat 54 with the movable valve body 56. In the figure, reference numeral 61 is an O-ring, which is used to seal each part to prevent liquid leakage. Since the hydraulic fluid storage tank 28 connected to the discharge passage 24 and the plantar pump 29 for circulating the hydraulic fluid to the master cylinder 21 have a known configuration, a description thereof will be omitted. Next, the braking action provided with the androlock device having the above structure will be explained. When anti-lock is not applied during normal operation, a large flow path communicating between the pressure source side and the wheel brake side is in an open state, as shown in FIG. 2 (1). When the anti-lock is not applied, the discharge valve 26 of the solenoid valve is not supplied with electricity, so the five coils are de-energized and the movable valve body 56 closes the valve seat 54.
The second outlet 36 side of the flow control switching valve 25 is closed. When non-anti-lock, spool 4! is the introduction path 37 of the sleeve 32, which is biased by the return spring 49 and is located at the upper end position in the figure, and is in constant communication with the hydraulic fluid inlet 34.
(2) communicates with the third liquid passage 44 of the spool 41, and the fourth a liquid passage 45 communicates with the first outlet passage 38 of the sleeve 32. ], the inlet 34 of the flow 1 control switching valve 25 is connected to the inlet passage 37 - the third liquid passage passage 44 - the first liquid passage passage 42A -.
It communicates with the first outlet 35 through a large flow path composed of the fourth fluid passage 45 and the first outlet passage 38, and the hydraulic fluid is supplied from the master 7 cylinder 2I to the wheel brake 23 according to the amount of depression of the plagiarism pedal 20. It is possible to control the brake by feeding the brake. On the other hand, when a wheel speed detector or the like (not shown) detects the occurrence of excessive slip or its sign and establishes an anti-lock state, the coil 59 of the electromagnetic exhaust valve 26 is supplied with power and excited. Therefore, the armature 55 is lowered in the figure, and the movable valve body 56 is moved down against the spring 60 to open the valve seat 54, and the hydraulic fluid flows out from the second outlet 36 of the flow h1 control switching valve 25. is possible. Therefore, entrance 3
4. Between the pressure at the upper end of the spool 41 communicating with the introduction path 37, the third liquid passage 44, and the first liquid passage 42A, and the pressure at the lower end of the spool 41 connected to the second outlet 36. A pressure difference is generated between the spools 41 and 41 due to the biasing force based on this pressure difference.
It moves against the biasing force of the return spring 49, that is, it moves downward in the figure. Yo. First, as shown in FIG. 2 (IT), the fourth liquid passage 45 of the spool 41 and the first outlet passage 38 of the sleeve 32 are
The connection with that is cut off and the large flow path is closed. Similarly, the fifth liquid passage 46 of the spool 4I and the sleeve 32
Since the communication with the second outlet path 39 is cut off, the supply of hydraulic fluid to the wheel brakes 23 is stopped. Furthermore, when the outflow of the hydraulic fluid from the discharge valve 26 progresses and the inflow spool 41 descends and reaches the position shown in FIG. The first outlet 35 communicates with the second outlet passage 39 through the second outlet passage 39 in the radial direction, the fifth liquid passage passage 46, the second liquid passage passage 42B1 in the axial direction, and the second outlet 36 through the return spring chamber 51. A decompression passage communicating with is opened. Therefore, the hydraulic fluid in the wheel brake 23 flows from the first outlet 35 to the second outlet 36.
The brake fluid passes through the discharge valve 26, which is open, and is discharged to the discharge passage 24, and anti-lock is applied by reducing the brake pressure. When the spool 41 is further lowered, it reaches a position where it does not communicate with the third liquid passage 44 or the introduction passage 37, and the inflow of the working fluid from the inlet 34 is blocked. In this state, spool 4
The cross-sectional area of 1 is A1 The biasing force of the return spring 49 is F
5 brake pressure (that is, in this state, the second fluid passage 4
2B) is P, then the orifice 43
The pressure in the first liquid passage 42A before and after sandwiching the I) +
The balance is maintained by the F/A pressure horn. Hereinafter, F will be referred to as ΔP. If the power supply to the discharge valve continues, this balanced state will be maintained and the brake pressure will continue to increase.]
depressurization is progressing. When the anti-lock control changes to pressure increase and the discharge valve 26 is de-energized, the movable valve body 56 is urged by the spring 60 and moves to close the valve seat 54 and close the discharge valve 26 . Therefore, discharge of the hydraulic fluid from the second outlet 36 of the flow rate control switching valve 25 is stopped. In this state, while the pressure difference between the pressure source pressure and the wheel brake pressure exceeds a certain value ΔP, the biasing force of the return spring 49 biasing the spool 41 and the spool 41
The pressure difference ΔP determined by the cross-sectional area of the spool 41 is generated before and after the fixed orifice 43 provided inside the spool 41. An orifice is formed at the closing portion of the introduction passage 37 and the third fluid passage 44, and forms a small passage that passes through both orifices in series and communicates the pressure source and the wheel brake. That is, when the -1- differential pressure is greater than ΔP, the spool 41 is pushed down and the introduction passage 37 and the third
The opening of the liquid passage 44 is made small, and when the differential pressure is smaller than ΔP, the spool 41 is pushed up and the opening is made larger. Therefore, the opening 2 becomes a variable orifice through which only the flow rate necessary to keep the differential pressure constant is allowed to flow. On the other hand, when the differential pressure is maintained at ΔP, the flow rate passing through the fixed orifice 43 is constant, so the opening amount of the variable orifice is always opened to the extent that the same flow rate as this flow rate flows.
The amount will be automatically adjusted. Therefore, the inlet 34 - the introduction path 37 of the sleeve 32 - the third liquid passage 44 of the spool 41 -> the first liquid passage 42A - the orifice 43 - the second liquid passage 42B - the fifth liquid passage 46 - the second outlet passage 39 - A small flow path toward the first outlet 35 is opened, and a small flow of hydraulic fluid passing through the orifice 43 is supplied to the wheel brakes 23, thereby increasing the brake pressure. On this occasion,
The only path through which the high pressure source pressure leaks from the introduction path 37 through the space between the spool and the sleeve is the path leading to the first fluid passage 42A. This path includes the introduction path 37 and the third liquid passage path 44.
It is in parallel with the variable orifice formed between them, but in series with the fixed orifice 43. Therefore, as long as the leakage in this path is less than or equal to the flow rate m of the fixed orifice, it will be adjusted by the variable orifice, and there will be no problem. Since only a differential pressure of ΔP is applied to the other gaps between the spool sleeves, leakage is minimal. As the working fluid in the small flow 9 is supplied to the first outlet 35 side, the pressure difference between the inlet 34 side and the first outlet 35 side gradually decreases, and the pressure difference gradually decreases to the above pressure difference ΔP. , the spool 41 is moved to the second position by the biasing force of the return spring 49.
Return to the position shown in Figure (A) and open the large flow path described above. In the present invention, with the above configuration, if air is present in the return spring chamber 51 of the flow rate control switching valve 25, the air can be easily bleed regardless of whether the device is installed vertically or vertically. I can do it. That is, when the second outlet 36 is installed so as to be located downward as shown in FIGS. 1 and 2, the spool 11 is moved by the air in the return spring chamber 51 when the inlet 34 is pressurized. At that time, the spool 4 is placed near the -F part of the return spring chamber 51.
Since the fifth liquid passage 46 communicates with the second outlet passage 39 of the sleeve 32 by the movement of the spool 41, the air in the return spring chamber 51 flows through the fifth liquid passage 46.
It is naturally discharged through the small channels of the liquid passageway 46, the second outlet channel 3'9, and the first outlet 35. When the air in the return spring chamber 5I is discharged, the spool 41 stops moving and returns to the position shown in FIG. will be promptly removed. In this way, the air remaining in the return spring chamber of the flow control switching valve can be easily vented without opening the discharge valve 26. On the other hand, the arrangement of FIGS. 1 and 2 is reversed, and the second exit 3
6 is placed above, when the discharge valve 26 is opened and the pressure reduction flow path is opened, the return spring chamber is included in the pressure reduction flow path, and the pressure reduction flow path is a thick flow path that does not pass through an orifice or the like. Therefore, the air in the return spring chamber can be quickly discharged to the exhaust flow path side. As described above, according to the present anti-lock device, air can be removed quickly and easily by arranging the second outlet 36 either upward or downward. Effects of the Invention As is clear from the above explanation, the present invention provides a discharge flow path branched from the main flow path that communicates the pressurization source (master turn ring) and the wheel brake, and provides a discharge flow path at the branch point 41. A spool having a liquid passage including an orifice is axially moved by a return spring into a sleeve of three boats having an inlet communicating with a pressure source, a first outlet communicating with a wheel brake, and a second outlet communicating with a discharge passage. In an anti-lock device, a non-power-operated flow control switching valve that can be slid freely is provided in the anti-lock device, and a discharge valve that is normally closed and opened by power supply during anti-lock is provided on the discharge flow path side. The liquid passage in the axial direction formed in the valve is separated by an orifice, and the liquid passage on one side becomes part of a large flow passage that communicates the inlet and the first outlet, while the liquid passage on the other side is separated by an orifice. The road is the first exit and the second exit.
Since it forms part of the pressure reducing flow path that communicates with the outlet, the structure of the flow rate control switching valve can be simplified. Furthermore, the inlet and first outlet of the flow control switching valve are bored in the outer peripheral wall of the sleeve in a direction perpendicular to the spool and the axial direction,
When the anti-lock is not on, the inlet and the first outlet are connected in a large flow path through the liquid passage formed in the spool, and one end of the sleeve 1; and the discharge valves consisting of electromagnetic valves are arranged in series so that the open end of the sleeve (1) is facing closed, so that the hydraulic fluid from the second outlet is directly guided to the discharge valve (114). Since the opening end of the sleeve of the flow control switching valve is configured as the second output end J, the open end of the sleeve is closed with a discharge valve made of a solenoid valve. This eliminates the need for end plugs that were conventionally required. In addition, the air in the return spring chamber of the flow rate control switching valve can be easily vented even when the flow rate control switching valve is installed upside down. In particular, when the second discharge port provided at the opening end in the axial direction is installed downward, it is possible to discharge the fluid naturally without opening the electromagnetically operated discharge valve. Conversely, even when the second discharge port is arranged in the -L direction, the return spring chamber is included in the decompression flow path in which a large flow rate is formed, so that the air in the return spring chamber can be easily and reliably removed. I can do it. In this way, the air in the return spring chamber, which could not be easily discharged with conventional flow rate control switching valves, can be discharged quickly and reliably, eliminating problems caused by residual air. Can you do it? Further, leakage between the spool and the sleeve does not cause any problems even if the pressure difference is small (8P) or the gap between the spool and the sleeve is somewhat large because the pressure difference is small (8P) or the gap is in series with the fixed orifice. y) It is easy to process the spool and sleeve, and it also has the effect of preventing sticking between them. Furthermore, the flow rate control switching valve described above has various advantages such as being easy to process and manufacture since there is no need to carve grooves on the inner peripheral surface of any of the constituent members. It's Shino.

[Brief explanation of the drawing]

FIG. 1 is a partially cross-sectional overall configuration diagram showing an embodiment of the present invention;
Figures 2 (l
1 is a partially cross-sectional overall configuration diagram showing a conventional example. 20... Brake valve, 21... Master cylinder, 22... Main flow path, 23... Wheel brake,
24・Discharge flow path, 25・Flow path control switching valve, 26
...Discharge valve, 27.. Housing, 31.. Hole,
32 ・Sleeve, 34 ・Inlet,
35...first exit, 36...second exit, 37
...Introduction path, 38...First outlet path, 39...Second outlet path, 41...Spool, 12A, 42B, 44.45.46...Liquid passage, 4
3 - Orifice, 49... Return spring, 51... Return spring chamber, 54... Fixed valve seat, 55... Armature, 5
6...Movable valve body, 58...Stator, 5 pieces.
... Coil, 6 (] ... Spring. Patent applicant Sumitomo Electric Industries Co., Ltd. Agent Patent attorney Aoyama Bohha and two people Figure 2 (1)
) Figure 2 (■) Figure 2 (I[I)
Figure 2 (IV) Procedural amendments Dear Commissioner of the Patent Office, April 18, 1999 1, Indication of the case 1988 Patent Application No. 135041 Mori 2, Title of the invention Anti [Book device 3, Person making the amendment Case] Relationship with Patent Applicant Address Kita d, Chuo-ku, Osaka City, Osaka Prefecture (4th J, No. 5-33 Name (213)) Sumitomo Electric Industries, Ltd. Representative Satoshi Kawakami Department 4, Agent Address 540 Osaka City, Osaka Prefecture Chuo Sekiken 2-1-61 Self-corrected specification 1, Title of the invention Anti-lock device 2, Claim 1, Discharge flow path is branched from the main flow path that communicates the pressurization source and the wheel brake. At the same time, a discharge valve that opens by electromagnetic operation is provided on the discharge flow path side, and the flow control switching valve is connected to an inlet communicating with a pressurizing source and communicating with a wheel brake. A spool that connects a liquid passageway that includes a fixed orifice therein is biased in the axial direction in an at least one-way opening I'll that has a first outlet and a second outlet that communicates with the discharge passageway. Due to the relative axial position of the Subur and the inner cylinder,
When the anti-lock is not activated, the large passage connecting the inlet and the first outlet is opened, and when the anti-lock is depressurized and the discharge valve is open, the large passage is closed and the first outlet and the second outlet are opened.
By opening the pressure reducing flow path communicating with D, and when repressurizing the anti-lock after closing the discharge valve, by forming a variable orifice between the spool and the first outlet, A small flow path communicating through the fixed orifice and the variable orifice in series is opened, and the inlet pressure and the first outlet pressure (1), $ jf h < -ra (when the bamboo is in the lower position, the return spring causes the above Each flow path is configured to return to the non-antilock position, and an axial liquid passage is formed in the spool separated by the fixed orifice in the front and back, and one of the liquid passages is side is -1
- An anti-lock device characterized in that it forms part of the enlarged flow path, and the other side forms part of the decompression flow path. 2. A discharge flow path is provided by branching from the main flow path that communicates the pressurization source and the wheel brake, and a flow rate control switching valve is provided in the branch, and a discharge valve that is opened by electromagnetic operation is provided on the discharge flow path side. The flow rate control switching valve includes an inner cylinder having an opening in at least one direction and having a first outlet communicating with the pressurizing source, a first outlet communicating with the wheel brake, and a second outlet communicating with the discharge flow path;
A spool that connects a liquid passage containing a fixed orifice inside is biased by a return spring and fitted so that it can slide freely in the axial direction.Due to the relative position of the spool and the spool in the axial direction, when the anti-lock is not activated, A large flow path communicating between the inlet and the first outlet is opened, and when the anti-lock pressure is reduced, that is, when the discharge valve is opened, the large flow path is closed and a pressure reduction flow path is opened that communicates the first outlet and the second outlet. Also, when the anti-lock pressure is increased again when the discharge valve is opened, a variable orifice is formed between the spool and the inlet (9), so that the inlet and the first outlet are connected to the fixed orifice and the variable orifice described above. Open the small channels that communicate in series, and when the inlet pressure and the first outlet pressure become too large, the return spring returns each channel to the non-anti-lock position. When the small flow path is configured, there is a leakage path that is formed in the gap between the spool and the inner cylinder and can communicate between the first outlet and the first outlet. 4. An anti-lock device configured to receive a differential pressure between the pressure and the first outlet pressure and to have no hole in parallel with the fixed orifice. 3. A discharge flow path is provided by branching from the main flow path that communicates the pressure source and the wheel brake, and a flow 1 control switching valve is provided at the branch, and a discharge valve that opens by electromagnetic operation is provided on the discharge flow path side. , the flow rate control switching valve has an inlet communicating with the pressure source, a first outlet communicating with the wheel brakes, and a second outlet communicating with the exhaust flow path;
The spool, which has a liquid passage including a fixed orifice inside, is urged by a return spring and fitted so as to be slidable in the axial direction, and due to the relative axial position of the spool and the straight shot, when the anti-lock is not activated, the above A large passage connecting the inlet and the first outlet is opened, and the passage is closed when the anti-lock pressure is reduced, that is, when the discharge valve is opened. i, li Open the depressurizing flow path that communicates the ITJ and the second outlet, and close the discharge valve 1
When repressurizing the anti-lock after F, by forming a variable orifice between the spool and the guard, the inlet and the first
A small flow path is opened in series through the fixed orifice, the variable orifice, and the outlet.
Differential pressure between the pressure and the first outlet pressure '7'i; (ttH-
Each flow path is configured to return to the non-anti-lock position by the return spring when lowered; , and an anti-lock device characterized by forming a liquid passage provided on the side wall of the spool and at the same time forming a variable orifice at one end to form a component of a small flow path. 3 DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to an anti-lock device, and more specifically, in a brake stem for an automobile, a wheel speed detector, a vehicle body speed detector, etc. are used to detect a locked state of a wheel, When excessive slip occurs or signs thereof are detected due to excessive braking, the solenoid valve is activated to reduce the brake pressure.
There is also a system that suppresses and controls the braking force to an optimum level by regulating the pressure. In the past, various proposals have been made regarding this type of anti-lock device. For example, the one disclosed in Japanese Patent Publication No. 49-28307 discloses a pressure source (operated by the operation of a brake pedal). A normally open inlet valve is provided in the main flow path that communicates between the master cylinder (master cylinder) and the wheel cylinder of the brake device, while a normally closed discharge valve is provided in each of the discharge flow paths that communicate between the wheel cylinder and the brake fluid storage tank. The inlet valve and the discharge valve are both electrically operated in response to a detection signal from the anti-lock detection means. In this device, when the anti-lock is not activated, power is supplied to the inlet valve and the discharge valve, and the hydraulic fluid flows into the wheel cylinder according to the amount of depression of the brake pedal, while when the anti-lock is not activated, that is, when the brake fluid pressure is When reducing the pressure, power is supplied to the introduction valve and the discharge valve, so that the introduction valve closes and the discharge valve opens, thereby discharging the working fluid from the wheel cylinder side into the storage tank. In addition, when pressurizing the brake fluid pressure again, the inlet valve is opened and the discharge valve is closed while power is not supplied.Furthermore, when the brake fluid pressure is to be maintained at a constant pressure, power is supplied only to the inlet valve and the valve is closed. Since the discharge valve is in the closed position, the brake fluid pressure is kept constant. In this way, this device can control in three modes: pressure reduction, pressure increase, and constant pressure maintenance, but it is possible to control the valves operated by power supply in two modes.
In other words, it requires an inlet valve and an outlet valve, which has the disadvantage of increasing the cost due to an increase in the number of parts and the labor required for installation. An anti-lock device that eliminates the above drawbacks and has a simplified configuration with a single solenoid valve is U, S, P4.715
, 666. The device is shown in Figure 3 (1) (I
It consists of the configuration shown in I), and the main flow path 3 that communicates the pressure source 1 and the wheel cylinder 2 is provided with the electromagnetically actuated introduction valve. A flow rate control switching valve 5 with a 1-2 position switch is provided, and an electromagnetic discharge valve 7 with a normally closed 2-bottom 2-position switch is provided in the discharge passage 6. In this device, the non-electromagnetic flow control switching valve 5 and the electromagnetic discharge valve 7 are combined to perform undyed rotor control in two modes of pressure reduction and pressurization only. As shown in the figure, the flow control switching valve 5 has a structure in which a spool 12 is fitted into an inner cylinder 11 formed in the Norinda block IO so as to be slidable in the axial direction by biasing the spool 12 with a spring 4. An inlet 13 through which the hydraulic fluid from the mask ring flows into the inner cylinder It, a first outlet 14 through which the hydraulic fluid flows out from the wheel cylinder, and a first outlet through which the hydraulic fluid flows out through the discharge valve 7 to the hydraulic fluid storage tank. It has a structure in which two exits 15 are provided in a direction perpendicular to the axial direction. In the flow rate control switching valve, if there is air (bubbles) in the return spring chamber 17 of the inner cylinder 11, the bubbles will collapse when the pressure of the person [113] increases, causing the spool I2 to move to the anti-lock position, causing sudden acceleration. Not only is pressure impossible, but in that state (FIG. 3 (11)) the return spring chamber 17 connects the inlet 13 with the fixed orifice 19 via the passage I8, and the second outlet 15 with the inlet 114. It is separated by a variable orifice formed by the end face 20 of the spool I2 and the hole 21 in the inner cylinder, so it is difficult to discharge air bubbles, and the structure is such that air cannot be easily vented. The difficulty in bleeding air is that even if the flow rate control switching valve is oriented vertically, and even if the electromagnetically operated discharge valve is operated (I2), the ship will not be changed.As you can see, air may remain in the return spring chamber. In some cases, brake pressure was not generated in the wheel brakes in response to the pressure of the brake pedal, resulting in poor brake illumination.Furthermore, at least one of the inner cylinders of the flow control switching valve Opening 1
Therefore, an end plug is required to close the open end, which has the disadvantage that the number of products increases and installation is time-consuming, leading to high costs. Furthermore, during the repressurization process when the electromagnetic discharge valve is closed, if the leakage between the spool and the cylinder is not suppressed to 70%,
This also had the disadvantage of increasing costs, as a flow rate greater than the design value set by the return spring and orifice would flow to the wheel brakes, requiring sufficient machining accuracy for the spool and inner cylinder. Means for Solving the Problems The present invention attempts to solve the above-mentioned drawbacks by installing a discharge flow path branching from the main flow path that communicates the pressurization source and the wheel brake, and installing the discharge flow path in the main flow path that communicates the pressurization source and the wheel brake. At the same time, a normally closed discharge valve that is opened by electromagnetic operation is provided on the exhaust flow path side. 1 via outlet and discharge valve 1. A spool that flows through a liquid passage including a fixed orifice inside is biased in the axial direction by a return spring in an inner cylinder that is open in at least one direction and has a second outlet that communicates with the discharge passage. The spool and inner cylinder are slidably fitted, and the relative position of the spool and inner cylinder in the axial direction opens a large flow path that communicates the pressure source and the wheel brake when the anti-lock is not activated, and when the anti-lock pressure is reduced, that is, the discharge valve is opened. When the valve is turned on, the large flow path is closed and a pressure reduction flow path is opened that communicates the wheel brake with the exhaust flow path via the discharge valve, and when the anti-lock pressure is increased again, after the discharge valve is closed,
While the pressure difference between the pressure source pressure and the wheel brake pressure exceeds a certain value, the pressure difference △P determined by the biasing force of the return spring and the cross-sectional area of the spool or the fixed orifice provided inside the spool will increase. A variable orifice is formed in series with the fixed orifice between the pressure source and the wheel brake, allowing only a flow rate equal to the flow rate determined by this pressure difference and the area of the fixed orifice to pass through. A small flow path communicating between the pressurization source and the wheel brake is opened via the orifice, and the pressure difference between the pressurization source and the wheel brake is successively reduced by -]22 foot fi, and the above pressure difference △P
In B, the inlet of the flow rate control switching valve is configured so that when the flow rate decreases to , the large flow path connecting the pressurization source and the wheel brake is re-interrupted by the biasing force of the return spring to return to the non-operating state. The first outlet is defined as a hole bored in the side wall of the inner cylinder in a direction perpendicular to the axial direction of the inner cylinder.On the other hand, the open end of the inner cylinder in the axial direction is configured as the second outlet to the discharge flow path. , the second outlet is directly communicated with the return spring chamber so that the return spring chamber is included in the -j bipedal pressure reducing flow path, and the open end of the inner cylinder on the second outlet forming side The electromagnetically actuated discharge valves are installed in series so as to close the valve, and the spool is fitted into the inner cylinder and slides in the axial direction under the force of a return spring, separated by an orifice. Provide a liquid passage that penetrates in the axial direction,
One side of the liquid passage constitutes a part of the enlargement passage, and the other side constitutes a part of the decompression passage. In addition, the present invention has a fixed orifice and a 112
The configuration is such that the pressurizing iKi IE force and the IF wheel-to-wheel brake pressure differential are not directly applied to the gap between the spool sleeves that could form a leakage path. As mentioned in ``F1'', in this device, the second output of the flow control switching valve communicating with the discharge valve is inserted into the axial opening [-J end side of the inner cylinder, and the The liquid flow path provided in the spool and separated by an orifice forms a part of the decompression flow path together with the turn spring chamber described in the second paragraph, ``The liquid flow path is in direct communication with the return spring chamber, but one side of the flow path is provided in the spool and separated by an orifice.'' Therefore, the air in the return spring chamber can be easily discharged. Furthermore, since the open end of the inner cylinder is closed with a discharge valve, an end plug can be eliminated. Furthermore, when forming the small flow path, since there is no leak path with a large pressure difference between the spool and the inner cylinder in parallel with the fixed orifice, it becomes possible to set the gap between the spool and the inner cylinder to be slightly larger. EXAMPLES The present invention will now be explained in detail by way of examples shown in the drawings.
1. The master sill 21, which is a pressurizing source, operates in accordance with the amount of depression of the brake pedal 20, as shown in FIG. 1. It communicates with a wheel brake 23 including a wheel brake via a second flow path 22, and the main flow path 2
A discharge flow path 24 branches from 2, and a non-M magnetically operated flow rate control switching valve 25 and an electromagnetically operated discharge valve 26 are installed in series and in combination in one cylinder block 27 at the branch position. There is. The discharge passage 24 communicates with a known plunger pump 29 via a hydraulic fluid storage tank 28, and the plunger pump 29 communicates with the master cylinder 21 described in I' through a reflux passage 30. The hydraulic fluid discharged to 24 is pumped up to the master turn cylinder 21 side by a plunger pump 29. In this embodiment, in the configuration after the discharge flow path 24, a so-called reflux type structure as shown in I is exemplified.
The pressure fluid pumped up by the pump is introduced into the hydraulic booster via the pressure accumulator, and the fluid lost from the circuit between the master cylinder and the wheel brakes is replenished by the hydraulic booster through the discharge flow path. It is preferable that this is done by introducing the liquid whose pressure is regulated by the device into the same circuit. Also, it is sufficient if it is a so-called full power type pressurization source that does not have a master shilling. In short, the present invention can be used in combination with any desired pressure source structure or any structure subsequent to the discharge flow path. To explain in detail the structure of the flow rate control switching valve 25 and the discharge valve 26 provided at each point, a hole 31 is bored in one cylinder block 27, and the sleeve 32 of the flow rate control switching valve 25 is inserted into the hole 3! When the sleeve 32 is fitted and fixed, a discharge valve 2G consisting of a solenoid valve is installed on the opening side of the hole 3 so as to close the opening. However, it is possible to install an inner cylinder directly on the cylinder block 271.
is open at both ends, one end of which abuts the bottom of the hole 31, and the other end abuts the frame 33 of the discharge valve 26. A hydraulic fluid inlet 34 is formed between the outer circumferential surface of the sleeve 32 and the inner circumferential surface of the hole 31 to communicate with the main flow path 22 on the master cylinder 21 side. An outlet 35 is formed, and the opening axis on the side that contacts the frame 33 serves as a second outlet 36 for the hydraulic fluid that linearly communicates with the discharge valve 26 side. A filter 70 is attached to the inlet 34 to collect the working fluid flowing in from the master cylinder side. The sleeve 32 is provided with an introduction passage 37 that penetrates in the radial direction and communicates with the inlet 311 from the bottom side.
a radially penetrating first outlet passage 38 communicating with the outlet 35;
A second lead-out path 39 is provided. Inside the sleeve 32 is a spool 4 slidable in the axial direction.
1 is fitted. A first liquid passage 42A and a second liquid passage 4213 in the axial direction are formed in the axial center of the spool 11 with the orifice 43 in between. Further, a third liquid passage 44 and a fourth liquid passage 45 are formed which penetrate in the radial direction from the bottom side of the spool 4I and communicate with the first liquid passage 42A, and also communicate with the second liquid passage 42B. A fifth liquid passageway 46 in the radial direction is bored. The third liquid passage 44 communicates with and shuts off the introduction passage 37 and the inlet 34 according to the movement of the spool 41, and a variable orifice is formed at the mutual end edges of the third liquid passage 44 and the introduction passage 37. We are trying to make it possible to form. The fourth liquid passage 45 and the fifth liquid passage 46 are formed in front and back with the orifice 43 in between, and open and close as the first outlet passage 38 and the second outlet passage 39, respectively, in accordance with the movement of the spool 41. . The tip of the spool 4I is formed as a spring receiver 47, and the frame 3 communicates with the second outlet 36 of the sleeve 32.
A return spring 49 is compressed between the spring receiver 48 fixed to the inner surface of the liquid passage 71 of No. 3. - The filter 50 is attached to the spring receiver 48, and the sleeve 32,
Dust is collected from the working fluid flowing into the fluid passageway 71 through the return spring chamber 51 surrounded by the spool 41 and the frame 33. A discharge valve 26 installed to close the open end side of the hole 31
As shown in the figure, the liquid passage 7I and the fixed valve seat 54 are formed on the same axis as the second outlet 36 in the frame 33,
The fixed valve seat 54 is opened and closed by a 6I valve operating body 56, which will be described later. In this way, the second outlet 36 formed at the axial opening end of the sleeve 32 of the flow rate control switching valve 25 is arranged in series with the discharge valve 26, so that the working fluid flows linearly from the second outlet 36 to the discharge valve 26. I try to be guided. 1: The frame 33 of the discharge valve 26 is formed with a large-diameter hollow part 52 in the axial core part communicating with the liquid passage 71 communicating with the second outlet 36, and the hollow part 52 and the discharge flow are connected. A discharge passageway 53 communicating with the passageway 24 is formed. The above liquid passage 7
The fixed valve seat 54 is attached to the hollow part 52.
An armature 55 is slidably fitted in the axial direction, and a movable valve body 56 fixed to the armature 55 opens and closes the fixed valve seat 54. A stator 58 is disposed within the frame 33 at a position facing the armature 55.
A coil 59 is installed on the outer periphery of the valve, and when power is supplied, the coil 59 is energized to operate the armadure 5S and the movable valve body 56 in the direction of the arrow, thereby opening the valve seat 54. Further, a spring 60 is installed between the armadure 55 and the stator 58, and when power is not supplied, the spring 60 is biased to close the valve seat 54 with the movable valve body 56. i
The iJ valve body 56 and the armature 55 can be formed integrally, or they can be formed separately to provide a slight alignment function between them. In addition, in the figure, 61 is an O-ring, which is designed to prevent liquid leakage at each part. The hydraulic fluid storage tank 28 connected to the discharge flow path 24 and the plunger pump 29 that circulates the hydraulic fluid to the master turn cylinder 21 are of known construction, so a description thereof will be omitted. Next, the operation of the pre-Kinstet equipped with the androtator device having the above-mentioned structure will be explained. When anti-lock is not applied during normal operation, a large flow path communicating between the pressure source side and the wheel brake side is in an open state, as shown in FIG. 2 (+). When anti-lock is not applied, the solenoid valve υ
Since power is not supplied to the output valve 26, the coil 59 is de-energized and the movable valve body 56 closes the valve seat 5lI, so the second output LJ3G side of the flow n1 control switching valve 25 is closed. ing. In the non-antilock state, the spool 111 is biased by the return spring 49 and is at the upper end position in the figure, and the sleeve 32 is in continuous communication with the hydraulic fluid inlet 34.
The inlet passage 37 communicates with the third liquid passage 4.1 of the spool 41, and the fourth liquid passage 45 communicates with the first outlet passage 38 of the sleeve 32. Therefore, the person [ ] 34 of the flow m control switching valve 25 is connected to the introduction path 37 to the third liquid passage path 4 = 1-・first
Liquid passageway/52A-/fourth liquid passageway 45-/first outlet passage 38
It is connected to the first output [J35] through a large flow path, and controls the brakes by feeding hydraulic fluid from the master turn cylinder 21 to the wheel brakes 23 according to the amount of depression of the brake pedal 20. Is it possible to do something? -)J, If the wheel speed detector, etc. (U shown in the figure) detects the sign of excessive slip noise, and sets the anti-lock state, check the electromagnetic exhaust valve f- The 2G coil 59 is powered and excited. Therefore, the armadure 55 is lowered in the figure, and the movable fF body 56 is interlocked with the spring 60.
The valve 14U 5 - 1 is opened by lowering the valve 14 U 5 - 1 against the flow Gt control switching valve 25 to allow the hydraulic fluid to flow out from the second outlet 36 of the flow Gt control switching valve 25 . Therefore, the entrances 3 and 4, the introduction path 37, the 3111i
A pressure difference is created between the pressure on the upper end surface of the spool 41 communicating with the first liquid passage 42A and the pressure on the lower end surface of the spool 41 facing the second ill CI 3 G.
2. Due to the biasing force based on this differential pressure, the spool 41 moves against the biasing force of the return spring 49, that is, the spool 41 moves downward by 3 degrees in the figure. Fourth liquid passage 15 of spool 41 and sleeve 3
Communication with the first outlet path 38 of No. 2 is cut off, and the culprit flow path No. 11 is closed. Similarly, the fifth liquid passage 46 of the spool 41 and the sleeve 32
Since the communication with the second outlet path 39 is cut off, the supply of hydraulic fluid to the wheel brakes 23 is stopped.Furthermore, the outflow of hydraulic fluid from the discharge valve 26 progresses, and the spool 41 When the spool 4I is lowered and reaches the 4 position shown in FIG. 135
A depressurizing flow path communicating with the second outlet [136] is opened via the radial second outlet passage 39, the fifth liquid passage 116, and the axial second liquid passage 42B1 and the return spring chamber 5I. Therefore, the hydraulic fluid in the wheel brake 23 is the first Hj[135
The brake fluid then passes through the second outlet 1136, passes through the open discharge valve 26, and is discharged to the discharge flow path 24, and as a result of the brake pressure being reduced, anti-hooking is applied. When the spool 41 further descends, the third liquid passageway 14 is at a position where it no longer communicates with the introduction passageway 37, and the inflow of the working fluid from the inlet 34 is blocked. In this state, the cross-sectional area of the spool 41 is l~, the biasing horn of the return spring 19 is I2, and the brake pressure is equal to the pressure in the second fluid passage 4213 in this state. ) to I) and -4
Then, the force in the first liquid passage 42A sandwiching the orifice 43 is maintained at a pressure of P → F'/A and is balanced.). Hereinafter, [''/A is expressed as ΔI). If the discharge valve continues to be powered, this equilibrium state will be maintained and the subsequent brake pressure I] will continue to decrease. Anti-lock control will change to pressure increase, and the discharge will start. When the valve 26 is de-energized, the i+J moving valve F body 56 is biased by the spring 60 and moves to close the f' seat 54 and close the discharge valve 26. 25 second out [1
Stop discharging the hydraulic fluid from 36. In this state, while the pressure difference between the pressure source pressure and the wheel brake pressure exceeds a certain value ΔI), the biasing force of the return spring 49 that biases the spool 4I and the spool 4
A difference in mud pressure (Δ■) determined by the cross-sectional area of A variable orifice that allows only a small flow rate to pass through is formed at the closing part of the introduction passage 37 and the third fluid passage 44, and a small passage that passes through both orifices in series and communicates the pressure source and the wheel brake is formed. Formation 4-ru. That is, when the difference 1F is larger than ΔP, the spool 11 is pushed down to open the main wall 17 of the introduction passage 37 and the third liquid passage 44, and when the differential pressure is smaller than ΔP, the spool 41 is pushed down -4. -Enlarge the opening by falling. Therefore, ]-open/open] becomes a variable orifice through which only the flow 1', X, necessary to make the above-mentioned differential pressure constant, flows. On the other hand, if the above differential pressure is maintained at 8P, the fixed orifice
Since the passing flow h1 of 43 is constant, the opening amount of the variable orifice is always adjusted by 1 so that the same flow as this ME nl "1" will flow. Therefore, the inlet 34 - the introduction path of the sleeve 32; A small flow path from liquid path 42I3 to fifth liquid flow path 46 - second outlet path 39 - first outlet 35 is opened,
The hydraulic fluid in the small flow ti1 passing through the orifice 43 is supplied to the wheel brakes 23, and the brake pressure is gradually increased. At this time, the path through which the pressurizing source pressure of high LJ leaks from the introduction path 37 through the space between the spool and the sleeve is the path 11 that leads to the first liquid passage path 42A. This route is introduction route 3
7 and the third liquid passage 441, the IJJ variable orifice 1 (1, secondary, which is in series with the fixed orifice 13) is formed between the fixed orifice As long as the flow is F, it will be adjusted by the variable orifice, so there will be no problem.Since only a differential pressure of Δl is applied to the other gaps between the spool sleeves, the leakage will be minimal. As the working fluid is supplied to the first outlet 35 side, the pressure difference between the inlet 34 side and the first outlet 35 side gradually decreases, and when it reaches the pressure difference ΔP, it becomes low by 1.
Due to the biasing force of the return spring 49, the spool 4 is
1 returns to the position shown in FIG. 2 (1) and opens the large flow path described above. In the present invention, by having the configuration shown in "-", if air is present in the return spring chamber 51 of the flow rate control switching valve 25, the present invention can be operated in the vertical direction 11'. , it can be easily done like air handling. The second outlet 36 or 4-3 shown in FIGS. 1 and 2
When installed in the lower position, the air in the return spring chamber 51 will cause the
When the spool 41 moves and reaches the boosted pressure state, the fifth branch passage 46 of the spool 41 is located near the most part of the return spring chamber 5I.
6 communicates with the second outlet passage 39 of the sleeve 32 by movement of the spool 4I, the air in the return spring chamber 51 flows through the fifth liquid passage 46, the second outlet passage 39, and the first outlet 35.
is naturally discharged through the flow path. When the air in the return spring chamber 51 is discharged, the spool 11 no longer moves, and the biasing force of the four return springs
), it returns to the position shown in Figure 2 (1) and the large flow path is maintained, so the air should be removed quickly. In this way, the air remaining in the return spring chamber of the flow rate control switching valve can be easily removed without opening the exhaust valve 26. - If the arrangement of FIGS. 1 and 2 is reversed and the second outlet 36 is placed upward, when the discharge valve 26 is opened to open the vacuum passage, the return splinter chamber will be placed in the vacuum passage. included in
In addition, since the depressurizing flow path is a narrow flow path that does not involve an orifice or the like, the air in the return spring chamber can be quickly exhausted to the exhaust flow path. - As mentioned above, according to the present anti-rotation device, air can be quickly and easily bleed regardless of whether the second ffjD 3 G is oriented toward the side or downward. Storehouse 9 car W more! As is clear from the second explanation, the present invention provides a pressurizing source (
, the master cylinder) and the wheel brakes. A discharge flow path is provided at U' that branches from the 1-m flow path, and the inlet I communicates with the pressure source at the branch 11, and the wheel brake. A first outlet communicating with the second outlet and a second outlet communicating with the discharge passage;
[In the inner cylinder of the 3-boat with -J, install a non-electromagnetically actuated flow control switching valve that has a spool with a liquid passage including an orifice that can be slid in the axial direction with a return spring, and also In the hook device u, the axial liquid passage formed in the flow m control switching valve is separated by an orifice. , - The liquid passage on the blade side is connected so that it becomes a part of the large passage communicating between the inlet and the first outlet, while the liquid passage on the other side is connected to the 11j Ll and the second outlet.
The structure of the flow rate control switching valve can be simplified because the flow rate control switching valve is formed as a part of the pressure reducing flow path that communicates with the flow rate control switching valve. Furthermore, the inlet and the first outlet of the flow rate control switching valve are connected to each other through a liquid passage formed in the spool by perforating the side wall of the inner cylinder in a direction perpendicular to the spool and the axial direction. When communicating with f41 D through a large flow path, the opening at one end of the inner cylinder is configured as a second outlet to the discharge valve side, and the discharge valve consisting of a solenoid valve is connected to the Opening of the cylinder
Since they are arranged in series so as to close the J end, it is possible to eliminate the need for an end plug that was conventionally required. Ka, style 6
1. Air in the return spring chamber of the control switching valve can be easily vented. Especially when the second outlet provided at the opening end in the axial direction is arranged squarely, the electromagnetically operated discharge valve will not open. The remaining air can be discharged naturally. Conversely, even if the second outlet is placed on one side, a large flow rate will be formed. Therefore, the air in the chamber can be easily and reliably vented through the return spool.In addition, leakage between the spool and the inner cylinder is caused by a small pressure difference (∆
P) Or since it is in series with the fixed orifice, problems will not occur even if the gap between the spool and the inner cylinder is somewhat large. This makes it easy to process the spool and inner cylinder, and
This has the effect of preventing adhesion between the two. Furthermore, the J2, iQt&'Jl control switching valves are either constructed by engraving i:4 on the inner peripheral surface or not.
It has 111 different features, such as being easy to process and manufacture.

[Brief explanation of the drawing]

Fig. 1 shows an embodiment of the present invention, and Fig. 2 (IXIIXnl) (IV) is a sectional view showing the operation of the embodiment shown in Fig. 1. Fig. 3 (IXII) 1 is a partially cross-sectional overall configuration diagram showing a conventional example. 20... Plaque belt, 21... Master turn ring, 22... Main flow path, 23... Wheel brake,
24・Discharge flow path, 25・Flow path control switching valve, 26・
・Discharge valve, 27... Housing, 31... Hole,
32...Sleeve, 311...Inlet,
35...First exit, 36 Second exit, 37...Inlet path, 38...First outlet path, 39...Second outlet path,
41 ・Spool, ・12A, 42I3.44.45.46...Liquid passage,
43 Orifice, ・19... Return spring, 51... Return spring chamber, 5.1... Fixed valve seat, 55... Armature, 56- Movable valve body, 58... Stator, 59...
Coil, 60...spring. Patent applicant Sumitomo Electric Industries, Ltd.

Claims (1)

[Claims] 1. A discharge passage is provided branching off from the main passage communicating the pressurization source and the wheel brake, and a flow rate control switching valve is provided at the branch, and the valve is opened by electromagnetic operation on the discharge passage side. the flow rate control switching valve is disposed within an at least one-way opening sleeve having an inlet communicating with the pressure source, a first outlet communicating with the wheel brake, and a second outlet communicating with the discharge flow path;
A spool having a liquid passage including a fixed orifice therein is urged by a return spring and fitted to be slidable in the axial direction, and depending on the relative axial position of the spool and sleeve,
When the anti-lock is not activated, the large flow path that communicates the inlet and the first outlet is opened, and when the anti-lock pressure is reduced, that is, when the discharge valve is opened, the large flow path is closed and the pressure is reduced that communicates the first and second outlets. When the flow path is opened and the antilock pressure is increased again after the discharge valve is closed, a variable orifice is formed between the spool and the sleeve, so that the inlet and the first outlet are connected in series, and the fixed orifice and the variable orifice are connected in series. each flow path is configured such that when the inlet pressure and the first outlet pressure become approximately the same, each flow path is returned to the non-antilock position by the return spring, and In the spool, an axial liquid passage is formed which is separated from the front and back by the fixed orifice, one side of the liquid passage constitutes a part of the large flow passage, and the other side is used for the reduced pressure flow. An anti-lock device comprising a part of a road. 2. A discharge flow path is provided branching from the main flow path that communicates the pressurization source and the wheel brake, and a flow rate control switching valve is provided at the branch, and a discharge valve that opens by electromagnetic operation is provided on the discharge flow path side; The flow rate control switching valve has an inlet that communicates with the pressurization source, a first outlet that communicates with the wheel brake, and a second outlet that communicates with the discharge flow path, in a sleeve that is open in at least one direction.
A spool having a liquid passage including a fixed orifice therein is urged by a return spring and fitted to be slidable in the axial direction, and depending on the relative axial position of the spool and sleeve,
When the anti-lock is not activated, the large flow path that communicates the inlet and the first outlet is opened, and when the anti-lock pressure is reduced, that is, when the discharge valve is opened, the large flow path is closed and the pressure is reduced that communicates the first and second outlets. When the flow path is opened and the antilock pressure is increased again after the discharge valve is closed, a variable orifice is formed between the spool and the sleeve, so that the inlet and the first outlet are connected in series, and the fixed orifice and the variable orifice are connected in series. each flow path is configured so that when the inlet pressure and the first outlet pressure become approximately the same, each flow path is returned to the non-antilock position by the return spring, and When the small flow path is configured, it is a leakage path that is formed in the gap between the spool and the sleeve and can communicate the inlet and the first outlet, the pressure difference between the inlet pressure and the first outlet pressure. An anti-lock device, characterized in that the anti-lock device is configured such that it is free of interference and/or parallel to the fixed orifice. 3. A discharge flow path is provided branching from the main flow path that communicates the pressurization source and the wheel brake, and a flow rate control switching valve is provided at the branch, and a discharge valve that opens by electromagnetic operation is provided on the discharge flow path side. The flow rate control switching valve has an inlet that communicates with the pressurization source, a first outlet that communicates with the wheel brake, and a second outlet that communicates with the discharge flow path, in a sleeve that is open in at least one direction.
A spool having a liquid passage including a fixed orifice therein is urged by a return spring and fitted to be slidable in the axial direction, and depending on the relative axial position of the spool and sleeve,
When the anti-lock is not activated, the large flow path that communicates the inlet and the first outlet is opened, and when the anti-lock pressure is reduced, that is, when the discharge valve is opened, the large flow path is closed and the pressure is reduced that communicates the first and second outlets. When the flow path is opened and the antilock pressure is increased again after the discharge valve is closed, a variable orifice is formed between the spool and the sleeve, so that the inlet and the first outlet are connected in series, and the fixed orifice and the variable orifice are connected in series. each flow path is configured so that when the inlet pressure and the first outlet pressure become approximately the same, each flow path is returned to the non-antilock position by the return spring, and When the anti-lock is not activated, it is open as a part of the large flow path, and when the small flow path is formed after the discharge valve is closed, it is provided on the side wall of the sleeve in communication with the inlet so as to close the large flow path. When the small channel is configured, the set of the introduction channel and the liquid passage provided on the side wall of the sleeve closes the large channel and at the same time forms a variable orifice to become a component of the small channel. An anti-lock device characterized by: