JP2000145837A - Drum brake component made of light alloy - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enhance the strength and anti-abrasiveness of that part of a drum brake component made of light alloy abutting to other component(s). SOLUTION: A shoe web 38 (40) is made of aluminum alloy, and reinforcing members 42 and 44 made of steel are embedded in that part of the shoe web 38 which is engaged with a strut or a coupling member. In the part of embedmemt, mounting recesses 48 and 50 having an approx. channel shape are formed, and in the condition that the reinforcing members 42 and 44 are installed in these recesses 48 and 50, a press is applied to near the side wall surfaces 48b and 50b so that press dints 56 and 58 are formed. Thereby the aluminum alloy in the part with dints 56 and 58 is allowed to flow toward the reinforcing members 42 and 44 to fix integrally.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a drum brake component, and more particularly to an improvement in a light alloy drum brake component.

[0002]

2. Description of the Related Art To reduce the weight of a drum brake, it has been considered to manufacture various drum brake parts with a light alloy such as an aluminum alloy. However, there is a problem that sufficient strength and abrasion resistance cannot be obtained, damage (such as dents) occurs, and sufficient durability cannot be obtained due to early wear. In particular, high-strength parts such as iron are used in parts where strength is required, and the above-mentioned problem becomes conspicuous in contact parts with such high-strength parts.

The present invention has been made in view of the above circumstances, and an object of the present invention is to improve the strength and wear resistance of a portion of a light alloy drum brake component which is brought into contact with another component. To make it happen.

[0004]

In order to achieve the above object, a first aspect of the present invention is to provide a light alloy drum brake component, in which a reinforcing member having high mechanical strength is provided at a portion which is brought into contact with another component during use. Is buried.

According to a second aspect of the present invention, there is provided the light alloy drum brake component according to the first aspect of the present invention, wherein (a) a contact portion in which the other component is brought into contact with a portion of the drum brake component where the reinforcing member is to be embedded. A mounting that has a receiving surface that is substantially perpendicular to the direction and that is sufficiently larger than the contact area of the other components, and a pair of side wall surfaces provided on both sides of the receiving surface. (B) the reinforcing member includes a plurality of surfaces that are substantially brought into surface contact with the receiving surface and the pair of side wall surfaces, and the reinforcing member is provided in the mounting concave portion. In the arranged state, the stamping process is performed on the drum brake component in the vicinity of the side wall surface to form a coining recess, so that the light alloy in the coining recess portion flows toward the side wall surface side. The side wall surface is pressed by the reinforcing member, Characterized in that it a reinforcing member undetachable secured to the mounting recess.

According to a third aspect of the present invention, in the light alloy drum brake component of the second aspect, (a) the mounting recess has an engaging portion which is engaged with the reinforcing member from a side opposite to the receiving surface. The reinforcing member is inserted into the mounting recess from a direction parallel to both the receiving surface and the side wall surface, while (b) the reinforcing member is brought into substantially surface contact with the side wall surface. The engaging portion is provided with an engaging recess, and the light alloy enters the engaging recess when the coining recess is formed.

[0007]

In such a light alloy drum brake part, a reinforcing member having high mechanical strength is embedded in a portion which is brought into contact with other parts during use.
Even when a high-strength component such as iron is brought into contact, sufficient strength and wear resistance are obtained, and damage (such as dents) and early wear are suppressed.

According to the second aspect of the present invention, in a state where the reinforcing member is disposed in the substantially U-shaped mounting recess, a coining process is performed on a portion near the side wall surface to form a coining recess. Since the light alloy in the coining recess portion flows toward the side wall surface side and the side wall surface is pressed by the reinforcing member, and the reinforcing member is fixed to the mounting recess so as not to be detachable, the reinforcing member Can be easily assembled (buried). Further, the reinforcing member is brought into substantially surface contact with the receiving surface of the mounting concave portion, and the receiving surface is sufficiently larger than the contact area of the other parts. Since it is dispersed through the surface and transmitted to the main body portion (light alloy portion) of the drum brake component, there is no possibility that the main body portion is damaged (dents or the like) due to the contact load.

According to the third aspect of the present invention, the engaging member has an engaging portion which is engaged with the reinforcing member from a side opposite to the receiving surface, and an engaging concave portion is provided in a portion of the reinforcing member which is substantially brought into surface contact with the side wall surface. When the coining recess is formed, the light alloy penetrates into the engaging recess, so that the reinforcing member is more firmly fixed in the mounting recess.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Light alloy drum brake parts include, for example, shoe webs of brake shoes, those having the shoe webs and shoe rims integrally formed, and parking brake levers. It is manufactured by pressing or forging. As the light alloy, an aluminum alloy, a magnesium alloy, or the like is preferably used, and as the reinforcing member having high mechanical strength, iron, a steel material, or the like is preferably used. The mechanical strength is
A material having a predetermined mechanical strength is selected in consideration of the material of the other parts to be brought into contact, the contact load, and the like, including wear resistance and hardness. Also, all types of drum brakes, such as the leading / trading type and the duo-servo type, are covered.

It is desirable that the coining recesses be provided on both sides of the pair of side walls, but it is also possible to provide only one side. Although the coining recess may be parallel to the side wall surface, if the receiving surface is closer to the side wall surface, the pressing force against the reinforcing member due to the flow of the light alloy from the coining recess portion is reduced. Since the larger the distance from the surface, the larger the size, the larger the load that presses the reinforcing member toward the receiving surface is applied, and the reinforcing member is fixed in the mounting recess in a state of being in close contact with the receiving surface. If the pair of side wall surfaces themselves are inclined surfaces inclining inward as they are separated from the receiving surface, and the reinforcing member is also made to have a corresponding shape,
When the coining recess is formed and the side wall surface is pressed against the reinforcing member, the reinforcing member is pressed against the receiving surface. The reinforcing member can be fixed in various ways, such as bonding with an adhesive or driving a reinforcing member with serrations.

The engaging recess of the third invention may be a concave such as a discrete conical shape or a partial spherical shape, or may be a linear or curved groove-like concave. Can be adopted. In the case of a straight groove-shaped depression, the straight line direction is preferably a direction inclined with respect to the insertion direction of the reinforcing member, preferably a direction perpendicular to the insertion direction.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. FIG. 1 is a view showing an example of a duo-servo type drum brake. A pair of arc-shaped brake shoes 12 and 14 are supported on a backing plate 10 by a shoe hold-down device 16 and 18 so as to be able to expand from each other. Have been. The opposite ends of the brake shoes 12 and 14 are adapted to be brought into contact with the side surfaces of the anchor pins 20 fixed on the backing plate 10, respectively. Adjust wheel 22 for gap adjustment
Are respectively engaged with both ends of the connecting member 24 having Shoe return springs 26, 28 are stretched between the brake shoes 12, 14 and the anchor pin 20, and one end of the brake shoes 12, 14 is always brought into contact with the anchor pin 20. A spring (not shown) is also stretched between the other ends of the shoes 12 and 14 so that the engagement between the other end and the connecting member 24 is maintained.

A parking brake lever 32 is connected to one end of one brake shoe 14, that is, an end on the anchor pin 20 side, so as to be relatively rotatable around a connecting pin 30 substantially perpendicular to the backing plate 10. .
A strut 34 is bridged between a portion of the parking brake lever 32 close to the connection pin 30 and the other brake shoe 12, and a brake cable 36 is connected to the other end of the parking brake lever 32. I have. When the parking brake lever 32 is rotated counterclockwise through the connecting pin 30 via the brake cable 36, the brake shoe 12 is pushed out to the outer peripheral side via the strut 34, and is pressed by a brake drum (not shown). At the same time, the reaction force causes the connection pin 30 to rotate counterclockwise about the engagement position with the strut 34, whereby the brake shoe 14 is pressed by the brake drum and braking is performed.

Here, the brake shoe 12,
The shoe webs 38 and 40 and the parking brake lever 32 are made of a plate material or a forged product of an aluminum alloy which is a light alloy, and a portion of the shoe webs 38 and 40 where the struts 34 are brought into contact. And reinforcing members 42 and 44 are buried in portions to be engaged with the connecting member 24, respectively, as shown in FIG. Further, a reinforcing member 46 is buried in a portion of the parking brake lever 32 where the strut 34 is engaged, as shown in FIG. The shoe webs 38 and 40 are common members, and the reinforcing members 42 are provided on both of them. However, the shoe webs 40 on the parking brake lever mounting side are not always necessary. The shoe webs 38 and 40 and the parking brake lever 32 are light alloy drum brake parts, and the connecting member 24 and the strut 34 correspond to other parts that are brought into contact with the light alloy drum brake parts during use. . The strut 34 and the connecting member 24 may also be made of a light alloy, and a reinforcing member may be embedded in the contact portion. However, in the present embodiment, the strut 34 and the connecting member 24 are made of a steel material having high mechanical strength. Further, the reinforcing members 42, 44, 46 are also made of a steel material having high mechanical strength.

FIG. 2A shows a shoe web 38 (40).
(B) is an enlarged view of the vicinity of the reinforcing member 42, (c) is an enlarged view of the vicinity of the reinforcing member 44, and (d) is an enlarged view of the vicinity of the reinforcing member 44.
(b) is a DD sectional view, and (e) is an EE sectional view of (c). The shoe web 38 (40) is provided integrally with a shoe rim, and the reinforcing members 42, 44 are integrally fixed in mounting recesses 48, 50, respectively. Each of the mounting recesses 48, 50 has a strut 34,
The contact direction in which the connecting member 24 is brought into contact, that is, FIG.
(a) is provided at the bottom of the cutouts 52, 54 formed from the right direction, and is a substantially flat receiving surface substantially perpendicular to the contact direction and sufficiently larger than the contact area of the strut 34 or the connecting member 24. 48a, 50a and their receiving surfaces 48
It has a pair of flat side wall surfaces 48b and 50b provided at substantially right angles on both sides of the a and 50a, and has a substantially U-shape as a whole. These receiving surfaces 48a, 50a and side wall surfaces 48b, 50b are all formed perpendicular to the shoe web 38 (40), that is, perpendicular to the paper surface in FIGS. 2 (a) to 2 (c). The width of the mounting recesses 48, 50, that is, the vertical dimension in FIGS. 2B and 2C, is slightly larger than the notches 52, 54, and
The narrow portions 48c, 50c connected to the notches 52, 54 from the tips of the b, 50b function as engaging portions that are engaged with the reinforcing members 42, 44 from the opposite sides of the receiving surfaces 48a, 50a.

Each of the reinforcing members 42 and 44 has a substantially rectangular parallelepiped shape, and includes a plurality of flat surfaces which are substantially brought into surface contact with the receiving surfaces 48a and 50a and the pair of side walls 48b and 50b, respectively. I have. These reinforcing members 42 and 44 are parallel to both the receiving surfaces 48a and 50a and the side wall surfaces 48b and 50b, and more specifically, are perpendicular to the paper in FIGS. 2 (a) to 2 (c). Inserted into the mounting recesses 48 and 50 from different directions. Mounting recess 48,
Reference numeral 50 is provided so as to penetrate the shoe web 38 (40) in the plate thickness direction. For example, in a state where the shoe web 38 (40) is placed on a table having a flat surface, the reinforcing members 42 and 44 are provided from above. Is inserted so that the lower end (the right side in FIGS. 2 (d) and 2 (e)) located on the table side is substantially flush with the lower surface of the shoe web 38 (40).

Then, in this state, the shoe web 38 (4
0), a portion of the vicinity of the pair of side wall surfaces 48b and 50b is stamped to form a pair of stamped recesses 56 and 5b.
8, the aluminum alloy in the coining recesses 56 and 58 flows toward the side walls 48b and 50b, and the side walls 48b and 50b are pressed by the reinforcing members 42 and 44, and the reinforcing members 42 and Attach 44 to mounting recesses 48, 50
It is fixed so that it cannot be removed. The portions of the reinforcing members 42 and 44 which are brought into substantially surface contact with the side wall surfaces 48b and 50b are respectively perpendicular to the insertion direction, that is, FIG.
In (c), a V-shaped engaging groove 42 is formed in a straight line parallel to the paper surface.
a, 44a are provided, and the coining recesses 56, 58 are provided.
When the aluminum alloy is formed, the engagement grooves 42a, 44
a, the reinforcing members 42, 44 are more firmly held in the mounting recesses 48, 50. Engagement groove 4
Reference numerals 2a and 44a correspond to engagement recesses.

The stamping recesses 56 and 58 have inclined outer surfaces, so that the aluminum alloy can easily flow toward the inside, that is, toward the reinforcing members 42 and 44. The coining recesses 56 and 58 have a substantially rectangular shape in a plan view, as is apparent from FIGS. 2B and 2C.
The portion closer to 50a is formed so as to be further away from the side wall surfaces 48b, 50b, and the pressing force against the reinforcing members 42, 44 due to the flow of the aluminum alloy from the coining recesses 56, 58 is reduced from the receiving surfaces 48a, 50a. Since the distance between the reinforcing members 42 and 44 increases as the distance increases, the receiving surfaces 48
a, a load pressing on the 50a side is applied, and the receiving surface 48a,
The reinforcing members 42, 44 are fixed in the mounting concave portions 48, 50 in a state of being in close contact with the 50a.

FIG. 3A is an overall view of the parking brake lever 32, FIG. 3B is an enlarged view of a portion near the reinforcing member 46, and FIG. 3C is a cross-sectional view taken along line CC of FIG. . Reinforcement member 46
Are disposed on the parking brake lever 32 in the same manner as the reinforcing members 42 and 44. That is, while being inserted into the mounting recess 60 provided at the bottom of the notch 62, the coining recess 64 is formed by stamping on both sides of the pair of side wall portions 60b. Is firmly fixed. The mounting recess 60 is
3 is provided by penetrating the parking brake lever 32 in the thickness direction of the parking brake lever 32. For example, by inserting the reinforcing member 46 from above with the parking brake lever 32 placed on a flat surface table, FIG. As shown in (c), the lower end located on the table side is inserted so as to be substantially flush with the lower surface of the parking brake lever 32, and a coining recess 64 is formed in this state. Note that reference numeral 6 in FIG.
0a is a receiving surface, 60c is a narrow portion (engaging portion), and 46a is an engaging groove (engaging concave portion).

As described above, the light alloy drum brake components of the present embodiment, that is, the parking brake lever 32 and the shoe webs 38, 40 are made of a steel material having high mechanical strength in a portion which is brought into contact with other components during use. Since the reinforcing members 42, 44, 46 made of steel are buried, excellent strength and wear resistance can be obtained regardless of contact with the struts 34 and the connecting members 24 made of steel material, and damage (such as dents) and Premature wear is suppressed.

A substantially U-shaped mounting recess 4 is provided.
In a state where the reinforcing members 42, 44, and 46 are arranged in 8, 50, and 60, by stamping a portion near the side wall surfaces 48b, 50b, and 60b to form stamping recesses 56, 58, and 64, The aluminum alloy in the coining recesses 56, 58, and 64 flows toward the side walls 48b, 50b, and 60b, and the side walls 48b, 50b, and 60b are connected to the reinforcing member 4.
2, 44, 46, and its reinforcing members 42, 44,
Since the 46 is fixed in the mounting concave portions 48, 50, 60, the reinforcing members 42, 44, 46 can be easily assembled (buried).

The reinforcing members 42, 44, 46 are provided with
8, 50, and 60 are brought into surface contact with the receiving surfaces 48a, 50a, and 60a, and the receiving surfaces 48a, 50a, and 6 are received.
0a (strictly speaking, the contact area with the reinforcing members 42, 44, 46) is sufficiently larger than the contact area of the other parts (struts 34, connecting members 24), so that the reinforcing members 42, 44,
The contact load acting on the receiving surface 48a, 50a, 6
Oa is dispersed and transmitted to the shoe webs 38 and 40 and the main body portion of the parking brake lever 32, that is, the aluminum alloy portion, and the main body portion may be damaged (dents or the like) due to the contact load. There is no. The reinforcing members 42, 44, 46 are provided with receiving surfaces 48a, 50a, 60a.
Is brought into surface contact with almost the entire surface of the device.

Further, there are narrow portions 48c, 50c, 60c which are engaged with the reinforcing members 42, 44, 46 from the side opposite to the receiving surfaces 48a, 50a, 60a. Wall surfaces 48b, 50b, 60
b, the engaging grooves 42a, 44
a, 46a are provided and the aluminum alloy is engaged with the engagement grooves 42a, 44 when the coining recesses 56, 58, 64 are formed.
a, 46a, so that the reinforcing members 42, 44, 46 are more firmly attached to the mounting recesses 48, 5a.
0, 60 fixed.

In this embodiment, the coining recesses 56, 58,
64 is formed so as to be closer to the receiving surfaces 48a, 50a, 60a, away from the side wall surfaces 48b, 50b, 60b. , 44, 46 become larger as the distance from the receiving surfaces 48a, 50a, 60a increases, the reinforcing members 42, 44, 46
A load pressing the receiving surfaces 48a, 50a, and 60a acts on the receiving surfaces 48a, 50a, and 60a, and the reinforcing members 42, 44, and 46 are attached to the receiving surfaces 48a, 50a, and 60a.
Fixed within 0.

The embodiments of the present invention have been described in detail with reference to the drawings. However, these embodiments are merely examples, and the present invention is based on the knowledge of those skilled in the art. Can be implemented.

[Brief description of the drawings]

FIG. 1 is a front view showing an example of a duo-servo type drum brake including a light alloy drum brake component according to one embodiment of the present invention.

FIG. 2 is a diagram illustrating a shoe web of the drum brake of FIG. 1 in detail.

FIG. 3 is a diagram illustrating a parking brake lever of the drum brake of FIG. 1 in detail.

[Explanation of symbols]

24: Connecting member (other parts) 32: Parking brake lever (light alloy drum brake parts) 34: Strut (other parts) 38, 40: Shoe web (light alloy drum brake parts) 42, 44, 46: Reinforcement members 42a, 44a, 46a: engagement grooves (engagement concave portions) 48, 50, 60: mounting concave portions 48a, 50a, 60a: receiving surfaces 48b, 50b, 60b: side wall surfaces 48c, 50c, 60c: narrow portions. (Engaging portion) 56, 58, 64: coining recess

Claims (3)

[Claims] 1. A light alloy drum brake component comprising a light alloy drum brake component, wherein a reinforcing member having high mechanical strength is embedded in a portion which is brought into contact with another component when used. 2. A portion of the drum brake component where the reinforcing member is to be embedded is substantially perpendicular to a contact direction in which the other component is brought into contact, and is sufficiently larger than a contact area of the other component. A mounting recess having a large receiving surface and a pair of side walls provided on both sides of the receiving surface and having a substantially U-shape as a whole is provided. And a plurality of surfaces which are brought into substantially surface contact with a pair of side wall surfaces, and in a state where the reinforcing member is disposed in the mounting recess, coining is performed on a portion of the drum brake component near the side wall surface. Is applied to form the coining recess, the light alloy in the coining recess portion flows toward the side wall surface side, and the side wall surface is pressed against the reinforcing member, and the reinforcing member is attached to the mounting recess. 2. The fixing device according to claim 1, wherein Light alloy drum brake parts of the mounting. 3. The mounting recess has an engaging portion which is engaged with the reinforcing member from a side opposite to the receiving surface, and the reinforcing member is provided on both the receiving surface and the side wall surface. While the reinforcing member is inserted into the mounting recess from a parallel direction, an engaging recess is provided in a portion of the reinforcing member that is brought into substantially surface contact with the side wall surface, and when the coining recess is formed, The light alloy drum brake component according to claim 2, wherein the light alloy penetrates into the engagement recess.