JP2007015444A - Master cylinder with main reserver provided separately - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a master cylinder with its main reserver provided separately, which performs air bleeding certainly even in case the level difference between the main reserver and an auxiliary reserver must be decreased. <P>SOLUTION: An air bleeding port 7 fitted with a bleeder valve 8 is installed in the upper part of the auxiliary reserver 3 to be mounted on the master cylinder 1, and a working liquid lead-in port 6 is provided in the auxiliary reserver 3 in a position below the air bleeding port 7, and the working liquid lead-in port 6 and a working liquid supply port 5 of the main reserver 2 installed in a position independent of the master cylinder 1 are connected through a hose 4. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a master cylinder employed in a hydraulic brake device for a vehicle, and more particularly to a main reservoir separate type master cylinder in which a main reservoir is provided at a position independent of the master cylinder.

  As a conventional example of the master cylinder separately installed master cylinder mentioned above, for example, there is one disclosed in Patent Document 1 below.

  As shown in FIG. 6, the main reservoir separate-type master cylinder has the main reservoir 2 installed at a position independent of the master cylinder 1, and is connected to the auxiliary reservoir 3 attached to the master cylinder 1 by the hose 4 to assist from the main reservoir 2. The hydraulic fluid is supplied to the reservoir 3.

  This master reservoir separate type master cylinder uses the height difference H between the main reservoir 2 and the auxiliary reservoir 3 to cause the working fluid in the main reservoir 2 to flow to the auxiliary reservoir 3 with natural force. It is essential to provide a sufficient level difference between the main reservoir 2 and the auxiliary reservoir 3 for supply.

  However, recently, it has become difficult to provide a large difference in height between the master cylinder and the separate main reservoir from the viewpoint of vehicle design and pedestrian protection. From the standpoint of pedestrian protection, it is required to increase the distance from the vehicle hood to the main reservoir in the engine room, and the position of the master cylinder does not change. The height difference will be small.

  When the level difference between the main reservoir 2 and the auxiliary reservoir 3 cannot be sufficiently obtained and the position of the hydraulic fluid introduction port of the auxiliary reservoir 3 becomes higher than the hydraulic fluid supply port of the main reservoir 2, the hydraulic brake device When the circuit is filled with hydraulic fluid, the air cannot be vented.

Due to the air venting, there is a problem that the height difference between the main reservoir 2 and the auxiliary reservoir 3 cannot be reduced to a point where the demand can be met.
Japanese Utility Model Publication No. 2-81265

  An object of the present invention is to realize a master cylinder separate type master cylinder in which the above-described height difference is further reduced by reliably performing air bleeding even if the height difference between the main reservoir and the auxiliary reservoir is small. .

  In order to solve the above-described problems, in the present invention, an air vent port with a bleeder valve attached is provided above the auxiliary reservoir attached to the master cylinder, and further operates below the air vent port of the auxiliary reservoir. A liquid introduction port is provided, and the hydraulic fluid supply port of the main reservoir installed at a position independent of the master cylinder and the hydraulic fluid introduction port are connected by a hose so that the hydraulic fluid in the main reservoir is supplied to the auxiliary reservoir.

  Note that the bleeder valve attached to the air vent port may be a general screw-in type that opens and closes the air vent port by changing the screwing amount. It is preferable to provide a second engagement portion that is displaced in the axial direction with respect to the joint portion and to slidably insert the distal end side into the outlet portion of the air vent port. The bleeder valve configured as described above is provided with a valve fixture that is locked to the outer periphery of the cylindrical portion constituting the air vent port to prevent relative movement in the axial direction, and the locking portion at one end of the valve fixture is connected to the bleeder valve. A first insertion position where the air vent port is closed by being detachably locked to the first engagement portion or the second engagement portion on the outer periphery of the valve, and a second insertion position where the air vent port is opened. Can be selectively fixed.

  In the master cylinder separately provided master cylinder according to the present invention, a new air vent port is provided in the auxiliary reservoir, and a hydraulic fluid introduction port is provided below the air vent port. Accordingly, the position of the main reservoir can be lowered below that of the prior art so that the working fluid can flow from the main reservoir into the auxiliary reservoir.

  In addition, since the air vent port is provided at the upper part of the auxiliary reservoir, the difference in height between the main reservoir and the auxiliary reservoir is restricted, so that the internal space above the auxiliary reservoir must be placed above the hydraulic fluid supply port of the main reservoir. Even if a situation that does not satisfy the conditions occurs, the air in the auxiliary reservoir can be vented without hindrance.

  Embodiments of a master cylinder of the present invention will be described below with reference to FIGS. In FIG. 1, 1 is a master cylinder, 2 is a main reservoir installed at a different location from the master cylinder 1, and 3 is an auxiliary reservoir attached to the upper part of the master cylinder 1. The master cylinder 1 is a well-known master cylinder that pressurizes hydraulic fluid in a pressure chamber (not shown) with a piston (also not shown) to generate a brake fluid pressure, and therefore will not be described in detail. When the master cylinder 1 is in the non-operating state, the auxiliary reservoir communicates with the pressure chamber, and the hydraulic fluid is replenished to the pressure chamber.

The main reservoir 2 has a hydraulic fluid supply port 5, and the auxiliary reservoir 3 has a hydraulic fluid introduction port 6, and the hydraulic fluid supply port 5 and the hydraulic fluid introduction port 6 are connected by a hose 4. The hydraulic fluid is supplied (supplemented) from the reservoir 2 to the auxiliary reservoir 3.

  The hydraulic fluid supply port 5 is provided at the lowermost portion of the main reservoir 2 as in the prior art. On the other hand, the hydraulic fluid introduction port 6 is conventionally provided at the uppermost part of the auxiliary reservoir 3, but in the present invention, the hydraulic fluid introduction port 6 is provided at a position biased toward the bottom of the reservoir. The air vent port 7 is newly added to the upper side. If the air vent port 7 is provided above the hydraulic fluid introduction port 6, the air that has flowed into the auxiliary reservoir 3 by opening the air vent port 7 when the hydraulic fluid is sent from the main reservoir 2 and the brake circuit is vented. Can be discharged out of the circuit from the upper part of the auxiliary reservoir 3.

  Even if the height difference H between the main reservoir 2 and the auxiliary reservoir 3 becomes smaller than before, the level of the working fluid in the main reservoir 2 is set higher than the installation point of the air vent port 7. By setting the height position and filling the brake circuit with the hydraulic fluid while venting air from the air vent port 7, it works even on the part of the internal space of the auxiliary reservoir 3 that is higher than the hydraulic fluid introduction port 6. The liquid can be filled.

  In the illustrated master cylinder, the air vent port 7 is provided at the top of the auxiliary reservoir 3. A bleeder valve 8 for opening and closing the port is attached to the air vent port 7. 9 is a valve fixture, and 10 is a cap attached to the outlet of the bleeder valve 8. The bleeder valve 8 has a small-diameter valve portion 8c with an O-ring attached to the tip side, and an exhaust hole 8d behind the valve portion 8c. The valve portion 8c is a small-diameter port portion of the air vent port 7. The air vent port 7 is opened at the second position (see FIG. 2) where the air escapes. Further, the air vent port 7 is closed at the first position (see FIG. 3) where the valve portion 8c is inserted into the small diameter port portion of the air vent port 7.

  As shown in FIGS. 2 and 3, an engaging portion (annular groove) 11 a is provided on the outer periphery of the cylindrical portion 11 forming the air vent port 7. Further, on the outer periphery of the bleeder valve 8, a first engaging portion 8a and a second engaging portion 8b having the same structure as the engaging portion (annular groove) 11a are provided with their positions changed in the axial direction.

  The valve fixture 9 has a semi-cylindrical base portion 9a attached to the outer periphery of the cylindrical portion 11, and as shown in FIG. 4, the first engagement portion 8a or the second engagement portion is provided at one end of the base portion 9a. An engaging portion 9b that is detachably engaged with the joint portion 8b is provided, and an engaging portion 9c that is fitted to the outer periphery of the cylindrical portion 11 and engaged with the engaging portion 11a is provided at the other end. The locking portions 9b and 9c are press-fitted into the outer periphery of the engaging portion 11a and the first engaging portion 8a (or the second engaging portion 8b) to be engaged. The entrances of the engaging portions 9b and 9c are narrower than the outer diameters of the engaging portions 11a and the first and second engaging portions 8a and 8b, and the entrances are expanded by elastically deforming the engaging portions 9b and 9c. Then, the engaging portions 9b and 9c are fitted to the outer periphery of the engaging portion 11a and the first and second engaging portions 8a and 8b. The locking portions 9b and 9c are then elastically restored, the entrance is contracted, and the mounted state of the valve fixture 9 is maintained.

  In the example including the bleeder valve 8 and the valve fixture 9, the air vent port 7 is opened and closed by simply sliding the bleeder valve 8 from the second position to the first position or vice versa. It can be carried out. Specifically, the bleeder valve 8 is held at a position where the air vent port 7 is opened by the valve fixture 9 (second position shown in FIG. 2), and the air inside the auxiliary reservoir 3 is vented. Once the valve fixture 9 is removed, the bleeder valve 8 is slid into and pushed into the position where the air vent port 7 is closed (first position shown in FIG. 3). Can be used, and the work at the time of air venting is simplified.

  The bleeder valve to be used is preferably the one shown in FIGS. 2 and 3, but a screw-in bleeder valve 18 (see FIG. 5) in which the air vent port 7 is opened and closed by changing the screwing amount with respect to the cylinder portion 11. ).

  The material of the valve fixture 9 is not particularly limited. It is also conceivable to use those formed of hard resin in addition to those formed of metal.

The side view which shows the outline | summary of an example of the main reservoir separate type master cylinder of this invention Enlarged sectional view of the bleeder valve mounting part when the air vent port is opened Enlarged cross-sectional view of the bleeder valve attachment when the air vent port is closed Perspective view of bleeder valve fixture Sectional drawing which shows the other example of a bleeder valve Side view showing an overview of an example of a conventional main reservoir separate master cylinder

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Master cylinder 2 Main reservoir 3 Auxiliary reservoir 4 Hose 5 Hydraulic fluid supply port 6 Hydraulic fluid introduction port 7 Air vent port 8 Bleeder valve 8a First engagement portion 8b Second engagement portion 8c Valve portion 8d Exhaust hole 9 Valve fixture 9a Base portion 9b, 9c Locking portion 10 Cap 11 Tube portion 11a Engaging portion H Difference in height between main reservoir and master cylinder

Claims (2)

In the upper part of the auxiliary reservoir (3) attached to the master cylinder (1), a bleeder valve (
8) is provided with an air vent port (7), and further, a hydraulic fluid introduction port (6) is provided below the air vent port (7) of the auxiliary reservoir (3), and the master cylinder (1) The hydraulic fluid supply port (5) of the main reservoir (2) installed at a position independent of the hydraulic fluid is connected to the hydraulic fluid introduction port (6) by a hose (4), and the hydraulic fluid in the main reservoir (2) is supplied to the auxiliary reservoir. The main reservoir separate type master cylinder supplied to (3). A first engagement portion (8a) and a second engagement portion (8b) are provided on the outer periphery of the bleeder valve (8) in different axial positions, and the distal end side of the bleeder valve (8) is connected to the air vent port. (
7) is provided slidably inserted into the engagement portion (11a) on the outer periphery of the cylindrical portion (11) forming the air vent port (7), and is provided with a valve fixture (9) that is locked so as not to move in the axial direction. A locking portion (9b) at one end of the valve fixture (9) is detachably locked to the first engaging portion (8a) or the second engaging portion (8b) on the outer periphery of the bleeder valve (8). The bleeder valve (8) can be selectively fixed at the first insertion position for closing the air vent port (7) and the second insertion position for opening the air vent port (7). The main reservoir separate master cylinder according to claim 1.

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