JPS6114979B2 - - Google Patents

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention relates to a master cylinder equipped with a reservoir, which is installed in an automobile, etc., and particularly relates to a master cylinder made of a metal cylinder body and a master cylinder formed on the wall of the cylinder body. a protrusion having an inner hole communicating with the interior of the protrusion;
The present invention relates to a master cylinder that is integrally formed with a synthetic resin reservoir, has a liquid passage communicating with the inside thereof, and has a mounting portion that tightly fits into the inner hole of the protruding portion via a sealing member.

[Prior art and its problems] For example, there is a master cylinder in which a hydraulic fluid reservoir is attached to the cylinder body with bolts, as shown in JP-A-53-132669. A pair of protrusions extending from the side wall to both sides are provided, and these are fixed to a portion of the cylinder body with bolts. This allows the reservoir to be attached to the cylinder body, and the reservoir is made of synthetic resin, and from the protruding piece to the liquid connection part (attachment part) of the reservoir or the protrusion part of the cylinder body where the liquid connection part fits. Since there is a considerable distance between them, when an external force acts on the reservoir, the protrusion deforms, causing the reservoir to topple over. Therefore, an abnormal external force acts on the sealing member (rubber) interposed between the liquid connection portion of the reservoir and the inner hole of the protruding portion of the cylinder body, deteriorating its sealing performance. Or seal protection becomes uncertain.

In the master cylinder described above, the reservoir collapses because the protrusion easily deforms when an external force is applied. Therefore, a part of the reservoir is shaped so that it does not easily deform even when an external force is applied, and this part is It is conceivable to attach it to the cylinder body by tightening it with bolts. In this way, even if an external force is applied to the reservoir, the reservoir will not fall over, and the sealing performance of the seal member will be improved.

However, simply tightening and fixing with bolts applies a considerable amount of stress to the part of the synthetic resin reservoir that is subjected to this tightening, resulting in permanent deformation due to heat or damage due to external force. occurs.

[Problem that the invention seeks to solve]

The present invention has been made in view of the above problems, and an object of the present invention is to provide a master cylinder in which a reservoir can be directly attached to a cylinder body with a bolt without tightening a part of the reservoir. Or consider it a technical issue.

[Means for solving problems]

The above object, in the configuration described at the beginning, is to form a hollow part in the mounting part so as to cross the liquid passage, to form a side hole passing through the side wall part of the protruding part, and to attach the mounting part to the mounting part. is tightly fitted into the inner hole of the protruding part so that the hollow part of the attaching part and the side hole of the protruding part are aligned, and the rod-shaped member is inserted into the inner hole of the protruding part through the side hole of the protruding part. This is achieved by a master cylinder including a reservoir, the reservoir being inserted into the hollow part of the cylinder and fixed to the protruding part to couple the reservoir to the cylinder body.

[Effect]

With the above configuration, the reservoir can be attached without falling down even if an external force is applied to the cylinder body, but since it is directly fixed by the rod-shaped member, it is not a reservoir but a protrusion of the cylinder body. Since the cylinder body is made of metal, the above-mentioned problems will not occur even if it is subjected to tightening stress from the rod-shaped member. The reservoir is made of synthetic resin,
According to the present invention, the rod-shaped member does not receive any tightening stress, so the above-mentioned problems can be avoided.

〔Example〕

EMBODIMENT OF THE INVENTION Hereinafter, an embodiment in which the present invention is applied to a tandem master cylinder equipped with a reservoir will be described in detail with reference to the drawings.

FIG. 1 is a side view showing a main part of a tandem master cylinder according to an embodiment of the present invention in cross section;
FIG. 3 shows cross-sectional views in the - line and - line directions of FIG. 1, respectively.

In the figure, a tandem master cylinder is shown as a whole at 1, and this tandem master cylinder 1
has a tandem reservoir 2 made of synthetic resin and a cylinder body 3 made of metal, which are connected to joints A and B.
At each of the connecting parts A and B, mounting parts 6 and 7 having liquid passages 4 and 5 communicating with the inside of the reservoir 2 are formed integrally with the bottom of the reservoir 2, respectively. On one side of the cylinder body 3, protruding boss portions 10 and 11 having inner holes 8 and 9 communicating with the interior thereof, that is, the hydraulic pressure generating chamber, respectively, are formed integrally with the cylinder body 3.

Referring to FIG. 2, which shows a cross section of one coupling part A, the mounting part 6 of the reservoir 2 is formed with a cylindrical part 13 having a hole 12 penetrating in the radial direction.
A stepped portion 14 is formed at a position slightly below this cylindrical portion 13. The mounting portion 6 is reinforced by a plurality of reinforcing rims 15. On the other hand, protrusions 16 and 17 are formed on the boss portion 10 of the cylinder body 3 at portions of the side wall corresponding to the holes 12 of the cylindrical portion 13, respectively.
A screw hole 18 is formed in one of the protrusions 16, and a recess 19 is formed in the other protrusion 17 on the inner hole 8 side.

The screw hole 18 of this one protrusion 16 has an inner hole 8
A bolt 21 having a shaft portion 20 slightly longer than the inner diameter of
is screwed together with a threaded portion formed near its head, and the shaft portion 20 is inserted into the hole 1 of the cylindrical portion 13 of the attachment portion 6 of the reservoir 2.
2 and insert the tapered part 22 at the tip of the shaft into the boss part 1.
0, and the mounting part 6 is fitted into the boss part 10.
The attachment portion 6 is coupled to the boss portion 10, and the attachment portion 6 is prevented from coming off from the inner hole of the boss portion 10. A stepped portion 24 is formed in the inner hole 8 of the boss portion 10, and this stepped portion 2
A ring-shaped sealing member 23 is clamped between the mounting portion 4 and the stepped portion 14 of the mounting portion 6. Inner hole 8 of boss portion 10
A return hole 25 and a replenishment hole 26 are formed at the bottom of the
Through these, the inner hole 8 of the boss portion 10 communicates with the hydraulic pressure generating chamber within the cylinder body 3. These holes 2
5 and 26 and the relationship between these holes 25 and 26 and the hydraulic pressure generating chamber are the same as those in a conventionally known tandem master cylinder, so their explanation will be omitted here.

According to the joint part A shown on the left side of FIG. 1 and in FIG. The mounting part 6 has a screw hole 1 at one end.
8, bolts 2 each supported at the other end in a recess 19;
1 to the boss portion 10, the connected state is reliably maintained. Furthermore, since a slight clearance is provided between the shaft portion 20 of the bolt 21 and the hole 12 of the cylindrical portion 13 of the mounting portion 6, the dimension between the mounting portions 5 and 6 of the reservoir 2 and the cylinder body 3 Even if the dimensions between the boss portions 10 and 11 do not match due to manufacturing errors, the reservoir 2 and the cylinder body 3 can be connected by compensating for the errors with the above-mentioned clearance. The reservoir 2 can be connected to the cylinder body 3, and after the reservoir 2 is connected to the cylinder body 3, dimensional changes due to changes over time can be avoided.
Even if the gap occurs in the reservoir 2 due to the existence of the above-mentioned gap,
This can prevent undue stress from occurring. Further, since the cylindrical portion 13 of the mounting portion 6 is located above the return hole 25, brake fluid suddenly flows from the return hole 25 into the inner hole 8 when the brake is released after the operation of the tandem master cylinder 1. Even if the brake fluid spouts out, the brake fluid hits the cylindrical portion 13 and its flow velocity is weakened, preventing the brake fluid level in the reservoir 2 from fluctuating unnecessarily, so a fluid level warning device is provided in the reservoir 2. If there is, the liquid level warning device will not malfunction.

Next, regarding the other joint B, see Figures 1 and 3.
This will be explained with reference to the figures. As is clear from the figure,
The lower end of the attachment part 7 of the reservoir 2 is formed into a small-diameter cylindrical shape, and a protrusion 28 extending in the radial direction is formed in the middle part of the attachment part 7, so that the passage 5 of the attachment part 7 is narrow at the middle part. It's summery. Projection part 2
A circular step portion 29 is formed adjacent to the lower side of 8,
On the other hand, a circular stepped portion 36 is formed near the inner lower end of the boss portion 11, and a ring-shaped sealing member 35 is clamped between these stepped portions 29, 30. The protrusion 28 of the mounting portion 7 is provided with a through hole 27 in the lateral direction, and the protrusions 32 and 33 of the boss portion 11 are provided with the aforementioned through hole 27.
Through-holes 30 and 31 coaxial with are bored. A return hole 37 and a supply hole 38 are bored in the bottom wall of the boss part 11, and the boss part 11 is inserted through these holes 37 and 38.
The inner hole 9 communicates with a hydraulic pressure generating chamber within the cylinder body 3.

The mounting portion 7 and the boss portion 11 have holes 30 and 31 formed in the projections 32 and 33 of the boss portion 11 at both ends thereof, which are inserted through a hole 27 formed in the projection 28 of the mounting portion 7.
They are connected by a spring pin 39 that is press-fitted from the hole 30 or 31 side so as to be located inside. The spring pin 39 has a substantially cylindrical shape and has a first
As clearly shown in the figure, it has a cutout groove along its length, one or both ends of which are tapered, and are introduced into the holes 30, 31 of the boss part 11 and the hole 27 of the mounting part 7. is facilitated. in this case,
In the illustrated example, both ends of the spring pin 39 are connected to the holes 3
0, 31, and the middle part of the spring pin 39 is also tightly fitted into the hole 27 of the protruding part 28 of the mounting part 7, but the middle part is loosely fitted into the hole 27, or the head is Even if the spring pin 39 is loosely fitted into the holes 30 and 31, it will not fall out, so it is clear that the reservoir 2 and the cylinder body 3 are reliably connected.

According to the coupling part B shown on the right side of FIG. 1 and in FIG. A portion of this is absorbed by the elastic deformation of the spring pin 39, reducing the possibility that the connecting portion, particularly the protrusion 28, will be damaged. Furthermore, since the inside of the protrusion 28 is located above the return hole 37, as is clear in FIG. . Further, since the spring pin 39 is supported at both ends, it reliably holds the reservoir 2 and the cylinder body 3 in a connected state, and increases the reliability of the connected state against vibrations of the vehicle body.

In the connection parts A and B described above, the reservoir 2 and the cylinder body 3 can be connected by a simple method such as screwing in the bolt 21 or press-fitting the spring pin 39, and the sealing performance at the connection part can also be improved. Step portions 14, 29 of mounting portions 6, 7 and boss portions 6, 7
A sealing member is disposed between the step portions 24 and 36 of the connector to ensure sufficient reliability, and the connection is reliable and has the effect of being sufficient against vibrations of the vehicle body. Furthermore, even if an external force acts on the reservoir 2, the reservoir 2 will not fall. Further, since the reservoir 2 is not subjected to tightening stress by bolts as in the conventional case, it is not permanently deformed by heat or damaged by external force.

Although the embodiments of the present invention have been described above, the present invention is not limited to these embodiments, and various modifications can be made based on the technical idea of the present invention.

For example, in the above embodiments, the structures of the joints A and B are different for the sake of simplicity of explanation and illustration, but these joints A and B may be the same. That is, the pair of joints between the reservoir 2 and the cylinder body 3 may have the structure shown on the left side of FIG. 1 and FIG. 2, or the structure shown on the right side of FIG. 1 and FIG. 3. Further, instead of the configuration in which the reservoir 2 and the cylinder body 3 are bonded together in a pair, that is, in two locations, as in the embodiment, a configuration in which the reservoir 2 and the cylinder body 3 are bonded at one location is also possible. In this case, any of the structures of the coupling portions A and B shown in the above-described embodiments may be used, and the coupling portions may be provided approximately at the center of the bottom of the reservoir 2.

Further, in the above embodiment, the mounting portions 6 and 7 are provided with holes 12 and 27, respectively, into which the bolt 20 and the spring pin 39, which are rod-shaped members, are fitted, but instead of these holes 12 and 27, the mounting portion 6,
It is clear that the reservoir 2 and the cylinder body 3 can be reliably connected even if a groove is formed in the outer circumferential wall of the cylinder 7 and the above-mentioned rod-shaped member is fitted therein.

In addition, in the connection part A of the above-described embodiment, the bolt 21 is connected to the protrusion 1 of the boss part 10 by the threaded part adjacent to its head.
Although the reservoir 2 and the cylinder body 3 are connected by screwing into the screw holes 18 of No. 6, a tapping screw may be used instead of the bolts 21. In this case, screwing of the tapping screw is guided by advancing the tip portion along the recess 19 of the protrusion 17.

Furthermore, in the connection part A of the above-described embodiment, the boss part 10
A screw hole 18 is formed in the protrusion 16, and the protrusion 17
Although it is said that a recess 19 is formed in the structure,
Instead of this, a configuration may be adopted in which the protrusions 16 and 17 are formed with through holes. In this case, the through hole of the protrusion 16, the hole 12 of the cylindrical part 13 of the mounting part 6, and the protrusion 17
The reservoir 2 and the cylinder body 3 are connected by screwing a nut into a threaded portion formed at the tip of a bolt inserted through the through hole.

Furthermore, in the joint A of the above embodiment, the shaft 20 of the bolt 21 extends into the recess 19 of the protrusion 17 of the boss 10, as shown in FIG. It is clear that the reservoir 2 can be reliably connected to the cylinder body 3 even if the hole 12 ends partway through.

Further, although the above embodiments are applied to a tandem master cylinder, the present invention can of course be applied to a single master cylinder.

As described above, according to the present invention, the attachment portion of the reservoir is tightly fitted into the inner hole of the boss portion, and rod-shaped members such as the bolt 21 and the spring pin 39 are inserted through the side holes 18, 30, and 31 of the boss portion. By inserting it into a hollow part such as a hole or groove in the reservoir mounting part,
Since the reservoir and the cylinder body are connected, the connecting action is not only simple, but also
Various effects can be achieved, such as satisfying required conditions such as sealing performance and bonding stability.

[Brief explanation of the drawing]

1 is a side view showing a part of a tandem master cylinder according to an embodiment of the present invention in cross section, FIG. 2 is a sectional view in the - line direction of FIG. 1, and FIG. 3 is a cross section in the - line direction of FIG. 1. It is a diagram. In the figure, 6, 7... mounting part, 8, 9...
... Inner hole, 10, 11 ... Boss part, 12 ... Hole, 1
8...Screw hole, 21...Bolt, 27, 30, 3
1...hole, 39...spring pin.

Claims (1)

[Claims] 1 A cylinder body made of metal, a protrusion formed on the wall of the cylinder body and having an inner hole communicating with the inside thereof, and a liquid passageway formed integrally with a synthetic resin reservoir and communicating with the inside thereof. and a mounting portion that tightly fits into the inner hole of the protruding portion via a sealing member, wherein a hollow portion is formed in the mounting portion so as to cross the liquid passage, and the protruding portion A side hole is formed in the side wall of the holder, and the mounting part is tightly fitted into the inner hole of the protruding part so that the hollow part of the mounting part and the side hole of the protruding part are aligned. The reservoir is coupled to the cylinder body by fitting the rod-like member into the hollow part of the mounting part through the side hole of the protruding part and fixing it to the protruding part. master cylinder.