JPS6059530B2 - Master cylinder reservoir fluid volume reduction detection device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a fluid level reduction detection device for a master cylinder reservoir used in a vehicle brake system or the like.

Conventionally, one of these is a float that has a permanent magnet and is movable according to changes in the liquid level, and a float that is fixed to a reservoir and can be activated according to the magnetic force of the permanent magnet when the float drops by a predetermined amount. Some floats include a reed switch and a partition that is provided in a reservoir and guides the movement of the float and defines a float chamber in which the float is accommodated.

In these devices, the partition wall is provided to prevent malfunction of the device.

In other words, when the level of the fluid normally stored in the reservoir fluctuates due to the vehicle starting, braking, turning, driving on rough roads, etc., the partition wall restricts the flow of fluid into and out of the float chamber. This prevents rapid liquid movement around the float in the room and prevents the float from moving significantly in the vertical direction. However, when such a partition wall is assembled into a reservoir as a component of a liquid volume reduction detection device, problems arise in that the number of parts increases and the assembly process becomes longer. Furthermore, when the partition wall is integrally formed with the reservoir, the shape of the reservoir itself becomes complicated, making it difficult to manufacture. Alternatively, when inserting a jig or the like into the reservoir to attach the reservoir to the master cylinder, the integrally molded partition wall may get in the way, creating a problem that the attachment work may become troublesome. The present invention has been made in view of the above-mentioned problems.It is an object of the present invention to provide a master cylinder reservoir fluid volume reduction detection device that can improve productivity and prevent malfunctions, and has the following characteristics: However, the partition wall is formed by a filter disposed at a fixed position within the reservoir.

By doing this, a partition wall is provided in the reservoir and a float chamber is defined at the same time as the filter is installed in the reservoir, which simplifies the manufacture of the reservoir, reduces the number of parts, and simplifies the assembly work. At the same time, malfunction of the device can be prevented by the partition wall as described above.

Hereinafter, the present invention will be explained in detail based on the illustrated embodiments.

FIG. 1 is a sectional view showing the first embodiment of the present invention, FIG. 2 is a sectional view taken along line A-A in FIG. 1, and FIG.
FIG. 4 is a sectional view showing a second embodiment of the present invention, and FIG. 5 is a sectional view taken along line CC in FIG. 4.

First, to explain the first embodiment, in the figure,
2 is the cylinder body of the tandem master cylinder,
A cylinder hole 4 for accommodating a piston, a piston cup, a return spring, etc. (none of which are shown) inside thereof.
is drilled.

6 and 8 are brake fluid discharge ports, 10 and 12 are return holes, 1
4 and 16 are supply holes.

Reference numeral 18 indicates a reservoir assembly, and the reservoir body 24 includes:
They are attached to the cylinder body 2 by screwing fittings 20 and 22 onto the boss portion of the cylinder body 2, respectively.

26 and 28 are sealing O-rings interposed between the reservoir body 24 and the cylinder body 4.

The fittings 20, 22 have holes 30, 32, return holes 10, 12, and supply holes 14, 1.
6 connects the inside of the reservoir 18 and the inside of the cylinder hole 4. 34 is a lid of the reservoir 18, and 36 is an elastic steel wire for fixing the lid 34 to the reservoir body 24.

38 is a rubber diaphragm whose edge 40 is fitted into the reservoir body 24 to seal the inside of the reservoir 18 and the outside air.

The diaphragm 38 has two annular tongue-shaped thin film parts 42,
44 is provided, and these thin film parts 42 and 44 move up and down in the reservoir 1 as the level of the brake fluid in the reservoir 18 moves up and down.
It is possible to move up and down depending on the difference between the atmospheric pressure outside the reservoir 8 and the pressure inside the reservoir 18. A filter 46 filters the brake fluid flowing from the reservoir 18 into the cylinder hole 4, and is in the shape of a rectangular tank with filter sections 48 and 50 provided at the bottom.

This filter 46 has an upper outer surface in close contact with the inner surface of the reservoir body 24, and downward protrusions 52 and 54 at the bottom of the filter
0 and 2, and is disposed at a fixed position within the reservoir body 24. A rectangular recess that is surrounded by a partition wall 56 extending upward from the bottom and has an opening at the bottom is formed in the center of the filter 46. A float 58, which will be described later, is housed in the recess. A float chamber 60 is defined. A small hole 61 is provided above the partition wall 56. The float 58, which can float on the brake fluid stored in the reservoir body 24, has a rectangular parallelepiped shape and is inserted into the float chamber 60 with a small gap between it and the partition wall 56. It is guided by a partition wall 56 and can move up and down in response to changes in the surface.
A permanent magnet 62 is integrally attached to the lower part of the float 58. A convex portion of an insulator is provided at the center of the reservoir body 24 and extends upward from the bottom, and a reed switch 64 is horizontally buried in the upper end of this convex portion. The reed switch 64 is a permanent magnet 62
When the float 58 is lowered by a predetermined amount, internal contacts (not shown) close according to the magnetic force of the permanent magnet 62. Reference numeral 68 is a cord for connecting the reed switch 64 and an alarm circuit (shown in the figure) for notifying the driver of a decrease in the amount of fluid.

Note that, as long as the partition wall 56 can guide the float 58 within a predetermined range, the filter 46 may be slightly movable in the vertical direction. The operation of the above device will be explained.

The illustrated state shows a state in which brake fluid has not yet been put into the reservoir 18. That is, the float 58 is lowered and the permanent magnet 62 comes into contact with the convex portion in which the reed switch 64 is embedded, and the contact of the reed switch 64 is closed. Now, the steel wire 36, the lid 34, and the diaphragm 38 are removed and the brake fluid is put into the reservoir 18, and the brake fluid is filtered by the filter parts 48, 50 of the filter 46 and flows into the holes 30, 32 of the fittings 20, 22. , through the supply holes 14 and 16, the return holes 10 and 12, the cylinder hole 4, and the discharge ports 6 and 8, and flows into the subsequent pipes, wheel cylinders, etc., and when the liquid level in the reservoir 18 rises, the float 58 is guided by the partition wall 56 and floats up, and when it further rises to a predetermined height, the contact of the reed switch 64 opens.

The brake fluid is further flowed into the reservoir 18 to the required level. Steel wire 36, lid 34 and diaphragm 38 are then attached to reservoir body 24 as shown. Even if the level of the brake fluid stored in the reservoir 18 is inclined relative to the reservoir body 24 due to the vehicle starting, braking, turning, etc., the float chamber 60 is provided in the center of the reservoir body 24 so that the float room 6
Since the height of the liquid level in 0 hardly changes, the float 58 will not fall significantly and the reed switch 64 will not be activated by the magnetic force of the permanent magnet 62. Furthermore, even if the vehicle shakes and the level of brake fluid in the reservoir 18 fluctuates, the partition wall 56 allows the float chamber 60 to
The brake fluid is regulated from flowing in and out to the float chamber 60, and rapid fluid movement within the float chamber 60 is prevented.
Fluctuation of the liquid level in the liquid is suppressed, and the reed switch 64 will not be activated by the magnetic force of the permanent magnet 62 due to the float 58 falling significantly. In this manner, when brake fluid is properly stored in the reservoir 18, the fluid amount reduction detection device will not malfunction and a false alarm will not be issued to the driver. When a fluid leak occurs in the brake system due to damage or the like and the brake fluid in the reservoir 18 decreases, when the fluid level in the reservoir 18 drops by a predetermined amount, the float 58 is guided by the partition wall 56 and lowers. , the contact of the reed switch 64 is closed by the magnetic force of the permanent magnet 62, and an alarm is issued to the driver via the alarm circuit.

Next, a second embodiment shown in FIGS. 4 and 5 will be described.

This embodiment is generally the same as the first embodiment, and components corresponding to those in the first embodiment use the reference numerals of the components in the first embodiment plus 100. , use the same name.

The filters 146a and 146b of this embodiment are provided for each brake system, and the bottoms of the filters 146a and 146b are respectively attached to the fittings 120 and 146b.
22, cylindrical parts 180, 182 are provided below the filter parts 14'8, 150, and O-rings 184, 18
6 into holes 130, 132 of fixtures 120, 122.

The cylindrical parts 180, 182 are provided with elastic hook parts 190, 191 having hooks 188, 189 at their tips. engages the lower end of the fixture,
Filters 146a and 146b are prevented from easily coming out of holes 130 and 132. In this way, the reservoir body 1
Each filter 146a, 14 disposed at a fixed position within 24
2 on each of the opposing facing walls 196 and 198 of 6b.
Each of the protruding walls 192 and 194 are integrally provided so that their ends face each other, and these protruding walls 192, 194
194 and facing walls 196 and 198, the float chamber 1
60 is defined. The horizontal cross section of the float chamber 160 has a shape that is almost similar to that of the float 158 and is slightly larger than that, and the movement of the float 158 can be guided by the protruding walls 192, 194 and the facing walls 196, 198. ing. Reference numerals 200 and 202 are grooves provided in each filter, so that even if one of the brake fluids in the reservoir 118 decreases due to a failure in one of the brake systems,
The brake fluid in the other brake system is prevented from dropping below the lower ends of the grooves 200, 202.

The rest of the configuration is the same as that of the first embodiment, and the operation of this embodiment is the same as that of the first embodiment, so a description thereof will be omitted. In the first or second embodiment described above, the following effects are achieved.

(1) A float chamber 60, 160 defined by the partition wall 56 or the protruding wall 192, 194 and the facing wall 196, 198 is provided in the center of the reservoir body 24, 124. Even if the brake fluid level is inclined with respect to the reservoir body 24, 124, the float 58, 1
The position of 58 does not change significantly, and furthermore,
Even if the fluid level fluctuates, the inflow and outflow of brake fluid into and out of the float chambers 60, 160 is regulated, and the brake fluid formed between the floats 58, 158 and the wall defining the float chambers 60, 160 is The space in which the liquid can move is small, preventing rapid liquid movement within the float chambers 60, 160, and suppressing fluctuation of the liquid level within the float chambers 60, 160, so that the positions of the floats 58, 158 are It won't change much.

Therefore, when the brake fluid level is normal, the floats 58,
The reed switches 64, 164 will not be activated by the magnetic force of the permanent magnets 62, 162 due to the large drop of the reed switch 158, and malfunction of the liquid volume reduction detection device can be prevented. (2) Guide the floats 58, 158 to the float chamber 6
Partition wall 56 or protruding wall 192,1 defining 0,160
94 and the facing walls 196, 198, the reservoir body 24, 1
A filter 46 or 146 disposed at a fixed position within 24
a, 146b, the filters 46, 146a, 146b are connected to the reservoir bodies 24, 124.
Since the walls for defining the float chambers 60, 160 can be provided by simply attaching them to the inside of the reservoir bodies 24, 124, there is no need to provide each of the aforementioned walls as dedicated parts for the fluid volume reduction detection device. It does not have to be integrally molded.

Therefore, the assembly process can be simplified without increasing the number of parts, and the reservoir bodies 24, 124 can be manufactured easily. Furthermore, the partition wall 56 or the protruding walls 192, 194
and the facing walls 196, 198 are the reservoir bodies 24, 124.
After being attached to the cylinder bodies 2, 102 by the attachments 20, 22 or 120, 122, they are installed inside the reservoir bodies 24, 124, so that when the attachments are screwed onto the bosses, each wall is It won't get in the way of your work,
Work efficiency can be improved. (3) The reed switch 64, 164 is embedded in the upper end of the convex portion provided in the reservoir body 24, 124, and the cylinder body 2, which is a magnetically permeable material,
By arranging the floats 58, 15 away from the mounts 20, 22, 120, 122,
8 decreases by a predetermined amount, the magnetic flux formed by the permanent magnets 62, 162 does not escape, so the reed switch 64,
164 can be operated accurately. (4)
Since the convex portion in which the lead switches 64, 164 are embedded acts as a stopper that restricts the downward movement of the floats 58, 158, separate stoppers are provided for the floats 58, 158. The structure can be simplified as there is no need to

Although the illustrated embodiments have been described above, the present invention is not limited to the above-described embodiments.

In other words, it is placed at a fixed position in the upper part of the reservoir body. A substantially plate-shaped filter may be integrally formed with a partition wall extending downward from the plate portion, and the partition wall may define a float chamber. The filter 46 of the first embodiment shown may be divided into two so that the horizontal cross section has a concave shape to form a partition wall. Also,
In the second embodiment shown in FIGS. 4 and 5, each of the filters 146a and 146b is provided with protruding walls 192 and 194 that abut against each other, but only one of the filters has the same effect as the other filter. A long protruding wall may be formed that extends toward the facing wall. In addition, in the embodiment, a type in which the reed switch is embedded in a convex portion provided above the bottom of the reservoir main body has been described, but the present invention is also applicable to a type in which the reed switch is disposed below the bottom of the reservoir main body, or It goes without saying that the invention can also be applied to a fluid volume reduction detection device in which the reed switch is disposed on the side of the reservoir body along the movement direction of the float.

As is clear from the above description, in the present invention, a partition wall that guides the movement of a float and defines a float chamber in which the float is accommodated is formed by a filter disposed at a predetermined position within a reservoir. As a result, it is possible to obtain a master cylinder reservoir fluid volume reduction detection device that improves productivity and prevents malfunctions.

[Brief explanation of the drawing]

FIG. 1 is a sectional view showing the first embodiment of the present invention, FIG. 2 is a sectional view taken along line AA in FIG. 1, and FIG. 3 is a sectional view taken along line BB in FIG.
4 is a sectional view showing a second embodiment of the present invention, and FIG. 5 is a sectional view taken along line C--C in FIG. 4. 18,118...Reservoir, 24,124...Reservoir body, 46,146a, 146b...Filter, 56...Partition, 58,158...
...Float, 60,160...Float chamber,
62,162...Permanent magnet, 64,164...Reed switch, 192,194...Protruding wall, 1
96,198... Facing wall.

Claims (1)

[Claims] 1. A float having a permanent magnet and movable according to fluctuations in the liquid level, a reed switch fixed to a reservoir and operable according to the magnetic force of the permanent magnet when the float drops by a predetermined amount, and a reed switch provided in the reservoir. A master cylinder reservoir fluid volume reduction detection device comprising a partition wall that guides movement of the float and defines a float chamber in which the float is accommodated, wherein the partition wall is disposed at a fixed position within the reservoir. 1. A master cylinder reservoir fluid volume reduction detection device, characterized in that it is formed by a filter.