JP4319955B2 - Reservoir for vehicle hydraulic master cylinder - Google Patents

Description

  The present invention relates to a reservoir of a hydraulic master cylinder for a vehicle that hydraulically operates a brake or clutch for a vehicle such as an automobile or a motorcycle. Specifically, the hydraulic fluid in the reservoir has a predetermined minimum amount of fluid. The present invention relates to a structure of a reservoir provided with a liquid level detection device for detecting this.

  A reservoir for storing hydraulic fluid is attached to a cylinder main body of a hydraulic master cylinder for a vehicle that hydraulically operates a brake or a clutch of an automobile or the like. Some of these reservoirs include a liquid level detection device that detects that the amount of hydraulic fluid has reached a predetermined minimum amount.

This liquid level detection device is formed by a reed switch provided at the bottom of a liquid storage chamber, a float for operating the reed switch, and a float guide for guiding the float so as to move up and down. The upward movement of the float, which is formed by a cylindrical rib protruding from the bottom wall and moves up and down in the float guide, is regulated by the float coming into contact with the upper wall of the reservoir (see, for example, Patent Document 1). .
JP 2002-67923 A

  However, in the above-described structure, it takes time to mold the ribs that constitute the float guide, and the upper surface of the reservoir restricts the upward movement of the float, so that the position where the liquid level detection device is provided is limited. In addition, if the reservoir shape is relatively flat with a low height, the float guide can be placed in the lower half of the lower half even if the upper wall of the reservoir regulates the upward movement of the float. If the reservoir height is high, the float guide must be formed so that it protrudes from the lower half of the reservoir to the upper half, and the lower half and upper half are dedicated. Had to be fused using a hot plate.

  Therefore, according to the present invention, the float guide can be easily formed, the shape of the reservoir can be appropriately changed without being constrained by the arrangement position of the liquid level detection device, and the lower half and the upper half of the reservoir can be changed. The heat plate for fusing the body can be shared with the heat plate used for welding the upper half of another type of reservoir to the lower half, and the hydraulic master cylinder for the vehicle can reduce costs. The purpose is to provide a reservoir.

In order to achieve the above object, in the first invention, a reed switch provided at the bottom of the liquid storage chamber, a float for operating the reed switch, and a float guide for guiding the float so as to move up and down are formed. In a vehicular hydraulic master cylinder reservoir equipped with a liquid level detection device inside the liquid storage chamber, the float guide surrounds and guides the float, and a cylindrical guide portion is provided at a lower end of the guide portion. a fitting portion which is circumferentially provided with is fitted into the annular projection of the float guide mounting portions provided on a bottom wall of the liquid reservoir chamber, and closes the upper opening of the guide portion to restrict the upward movement of the float and a restricting portion is formed in a bottomed cylindrical shape having integrally, to form a float chamber for accommodating the float vertically movably inside the float guide, the peripheral wall of the guide portion furo It is characterized by forming a hole for communicating preparative chamber and said reservoir chamber.

According to a second invention, in the first invention, the float guide is formed at a height that fits in the lower half of a reservoir formed by welding the upper half and the lower half. It is a feature.

  In the above invention, since the restricting portion for restricting the upward movement of the float is provided on the upper part of the float guide, the liquid level detecting device can always be stably operated regardless of the shape of the reservoir. Can be appropriately changed without being constrained by the arrangement position of the liquid level detection device. Further, the float guide can be easily formed, and the manufacturing cost can be reduced.

  Further, since the float guide is formed in a bottomed cylindrical shape integrally including the guide portion and the restriction portion, the float guide can be easily formed.

  Furthermore, in the case where the reservoir is formed by welding the upper half and the lower half, if the float guide is formed at a height that fits within the lower half of the reservoir, the weld surface is only the outer peripheral portion of each half. As a result, the heat plate used when welding the upper half and the lower half of the other types of reservoirs can be shared, and the cost can be reduced.

  Hereinafter, the present invention will be described in detail with reference to the drawings. FIG. 1 shows an embodiment in which the present invention is applied to a reservoir of a hydraulic master cylinder for braking. The hydraulic master cylinder 1 is a reservoir-integrated type having a reservoir 3 on an upper portion of a cylinder body 2, and reservoir mounting boss portions 2a and 2a are formed on the upper surface of the cylinder body 2 so as to protrude between the boss portions 2a and 2a. A reservoir connecting flange 2b is projected.

  The reservoir 3 is formed by welding a lower half 3a and an upper half 3b made of synthetic resin with a welding surface 3c, and the inside serves as a liquid storage chamber 4 for storing a working fluid. The lower half 3a has fitting bosses 3e and 3e that are fitted to the reservoir mounting bosses 2a and 2a, respectively, and a master cylinder connecting flange 3f that is connected to the reservoir connecting flange 2b on the outside of the bottom wall 3d. Provided. In addition, a reed switch 6 of the liquid level detection device 5 protrudes from the inner center of the bottom wall 3d, and a float guide mounting portion 3g for fitting the float guide 8 is protruded around the reed switch 6. The upper half 3b is provided with a hydraulic fluid injection portion 3h that rises in a substantially cylindrical shape at the top, and a cap 9 is mounted on the upper surface of the hydraulic fluid injection portion 3h.

  The liquid level detection device 5 includes the reed switch 6 mounted on the bottom wall 3d of the reservoir 3 and a float guide 8 that is erected on the bottom wall 3d around the reed switch 6 and forms a float chamber 7 inside. And a float 10 that moves up and down with the liquid level fluctuation of the working fluid in the float chamber 7 and switches the reed switch 6.

  The float 10 is formed of a short cylindrical lightweight material, and a concave portion 10a capable of accommodating the reed switch 6 is formed at the center of the lower portion, and a magnet 11 is embedded in the upper surface of the concave portion 10a. The float guide 8 has a larger diameter than that of the float 10, and a cylindrical guide portion 8 a that guides the vertical movement of the float 10 and a disc-shaped regulation portion 8 b that closes the upper opening of the guide portion 8 a are integrated. It is formed in a cylindrical shape with a bottom. A plurality of through holes 8c are formed in the peripheral wall of the guide portion 8a, and the float chamber 7 and the liquid storage chamber 4 communicate with each other through the through holes 8c. The float guide attaching part 3g is formed in a cylindrical shape into which the guide part 8a can be fitted, and has an annular protrusion 3i at the tip. At the lower end of the guide portion 8a, a fitting portion 8d to be fitted to the annular protrusion 3i is provided around.

  The liquid level detection device 5 is provided with a concave portion 10a of the float 10 at the upper part of the reed switch 6, and the fitting portion 8d of the guide portion 8a is fitted to the annular protrusion 3i, so that the float guide 8 is placed in the reservoir 3. It is assembled by attaching to the lower half 3a. Further, the float guide 8 is formed at a height that fits in the lower half 3a when assembled, and its upper end does not protrude toward the upper half 3b from the welding surface 3c.

  The lower half 3a and the upper half 3b provided with the liquid level detection device 5 formed as described above are welded at the welding surface 3c to form the reservoir 3. The reservoir 3 is formed by fitting the fitting boss portions 3e and 3e to the reservoir mounting boss portions 2a and 2a of the cylinder body 2 and screwing the screws to the reservoir connecting flange 2b and the flange 3f therebetween. It is attached to the upper part of the cylinder body 2. The working fluid is introduced into the liquid storage chamber 4, and the working fluid is also introduced into the float chamber 7 through the plurality of through holes 8c.

  The float 10 is at an upper position of the float chamber 7 when the working fluid in the liquid storage chamber 4 has a predetermined amount, and the upper surface of the float 10 and the regulating portion 8b are in contact with each other. In this state, the magnet 11 and the reed switch 6 are separated from each other, and the reed switch 6 is in a non-energized state. When the hydraulic fluid in the liquid storage chamber 4 is reduced, the float 10 is also lowered together with the liquid level of the hydraulic fluid in the float chamber 7, and when the hydraulic fluid in the liquid storage chamber 4 is reduced to a prescribed minimum amount, The magnet 11 is close to the reed switch 6 to switch the reed switch 6 to an energized state, and an alarm device and a warning light (both not shown) provided near the driver's seat are operated.

  The reservoir 3 of this embodiment is formed as described above, and the float guide 8 can be easily attached to the lower half 3a, and the structure of the lower half 3a and the upper half 3b has fewer ribs than in the prior art. A simple structure can be obtained, and the manufacturing cost can be reduced. Further, since the restricting portion 8b for restricting the upward movement of the float 10 is integrally provided on the upper part of the float guide 8, there is no restriction on the position where the liquid level detecting device 5 is arranged, and the shape of the reservoir 3 can be changed as appropriate. It becomes like this. Further, the float guide 8 is formed at a height that fits in the lower half 3a when assembled, and the upper end thereof does not protrude toward the upper half 3b from the welding surface 3c. The part where the upper half 3b is welded is only the outer peripheral part of each half 3a, 3b, and the heat plate used for welding the upper half and the lower half of other types of reservoirs can be shared, Cost can be reduced.

  The shape of the float or float guide of the present invention is arbitrary, and a spherical float, a cubic float guide, or the like can also be applied. The float guide can also be attached to the float guide mounting portion by press fitting or caulking. Further, the restricting portion is not limited to a disc shape that closes the upper opening of the cylindrical guide portion, and may be an engagement piece or a claw piece extending from the upper portion of the guide portion to the float upper side. Any shape can be used as long as the upward movement can be regulated. Furthermore, the present invention is not limited to being applied to a reservoir of a hydraulic master cylinder for brakes, but can be applied to a reservoir of a hydraulic master cylinder for clutches.

Partial cross-sectional explanatory drawing of a reservoir showing an embodiment of the present invention

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Hydraulic master cylinder, 2 ... Cylinder main body, 2a ... Reservoir mounting boss | hub part, 2b ... Reservoir connecting flange, 3 ... Reservoir, 3a ... Lower half, 3b ... Upper half, 3c ... Welding surface, 3d ... Bottom Wall, 3e ... Fitting boss part, 3f ... Master cylinder coupling flange, 3g ... Float guide mounting part, 3h ... Working fluid injection part, 3i ... Annular protrusion, 4 ... Liquid storage chamber, 5 ... Liquid level detection device, 6 ... reed switch, 7 ... float chamber, 8 ... float guide, 8a ... guide portion, 8b ... regulating portion, 8c ... through hole, 8d ... fitting portion, 9 ... cap, 10 ... float, 10a ... concave portion, 11 ... magnet

Claims (2)

The liquid storage chamber is provided with a liquid level detection device formed by a reed switch provided at the bottom of the liquid storage chamber, a float for operating the reed switch, and a float guide for guiding the float to move up and down. In the reservoir of the hydraulic master cylinder for a vehicle, the float guide is provided on the bottom wall of the liquid storage chamber and is provided around a cylindrical guide portion that surrounds and guides the float and a lower end of the guide portion. and a fitting portion which is fitted to the annular projection of the float guide mounting portion in a bottomed cylindrical shape which integrally includes a regulating portion for regulating the upward movement of the occlusion to the float an upper opening of the guide portion A float chamber is formed in the float guide to accommodate the float so as to be movable up and down, and a through hole is formed in the peripheral wall of the guide portion to communicate the float chamber and the liquid storage chamber. Vehicle hydraulic master reservoir cylinder, characterized in that it has. 2. The hydraulic pressure for a vehicle according to claim 1 , wherein the float guide is formed at a height of a reservoir formed by welding the upper half and the lower half to fit in the lower half. Master cylinder reservoir.

Images