JP2653922B2 - Leaf spring scarfing device and leaf spring centering method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a scarfing apparatus used in a process of manufacturing a leaf spring for an automobile and the like, and a method of forming a centerpiece of the leaf spring.

[0002]

2. Description of the Related Art In a leaf spring device for suspension of an automobile, an eyeball 2 wound like a leaf spring 1 shown in FIG. 6 is generally provided at an end of a parent leaf spring. The leaf spring 1 is attached to a bracket or the like of the vehicle body via a pin inserted inside. In order to form the centerpiece 2, the leaf spring 1 is heated to a hot state,
By winding the end of the leaf spring 1 around a cored jig,
An eyeball 2 having a predetermined curvature is formed. When the eyeball 2 is wound, a compressive force is applied to the material at a portion 2a inside the winding of the eyeball 2, and a tensile force is applied to the material at a portion 2b outside the winding.

For this reason, as shown in FIG.
In the cross-sectional shape along the axial direction, the material width is widened at the portion 2a inside the winding to escape the compressive force, and the material width is narrowed at the portion 2b outside the winding by pulling the material. Therefore, the maximum width of the centerpiece 2 after molding is
It becomes larger by ΔB on both sides than the material width B, so that a so-called drum-shaped deformation occurs. Eyeball 2 which became wide in this way
If the leaf spring 1 is left as it is, the eyeball 2 may interfere with a bracket or the like of the vehicle body when the leaf spring 1 is mounted on the vehicle body, and the mounting may be impossible.

[0004] Conventionally, the width of both ends 2c, 2d in the width direction of the eyeball 2 after forming is subjected to finish grinding using a grindstone or the like, ie, a so-called width-sliding process, and the above-mentioned width spread ΔB is cut off to obtain the maximum width of the eyeball 2. Is within a predetermined value.

[0005]

However, grinding using a grindstone imposes a large load on the grindstone, which takes time and effort and requires a great deal of work. In addition, since the grinding time is too long, the grinding operation has to be performed by out-of-line processing, which causes an increase in required man-hours.

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a leaf spring scarfing apparatus and a leaf spring forming method which can reduce the grinding process after forming the centerpiece.

[0007]

According to the present invention, a scarfing apparatus developed to achieve the above object has a means for holding a leaf spring before forming an eyeball, and winding the eyeball of the leaf spring. Of the part that is applied to both sides of the
Corner so that the width is smaller than the width of the part outside the winding
A pair of cutting edges which are arranged remembering degrees, of the pair
Roll the eyeball with the cutting blade touching the above part of the leaf spring
Drive means for moving the leaf spring in the longitudinal direction over the region to be moved.

[0008]

The leaf spring before the eyeball is formed is held at a predetermined position, and the cutting blade is applied from both sides of the leaf spring. The cutting blade is moved in the longitudinal direction of the leaf spring by the driving means, so that both side surfaces of the region where the eyeball should be wound are held by the cutting blade.
The part that is removed from the inside of the eyeball winding at that time
Material width is smaller than the material width of the part outside the winding
Become.

In the method of the present invention, when the eyeball portion is wound and formed, a scarf is previously formed so that the material width of the portion inside the winding at the end of the leaf spring is smaller than the material width of the portion outside the winding. Processing. After that, the part is involved and the eyeball is formed. When the eyeball is wound, a compression force acts on the inside of the winding and a tensile force acts on the outside of the winding, so that the material width on the inside of the winding tends to increase, but in the present invention, Since the scarfing process is performed in advance mainly on the inside of the winding, it is possible to prevent the width of the eyeball from expanding after the eyeball is wound and formed.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A first embodiment of the present invention will be described below with reference to FIGS. The scarfing apparatus 10 for a leaf spring shown in FIG. 1 is a pair of left and right scarfing machines 11, 20 for simultaneously performing scarfing on both ends 1a, 1b of a steel leaf spring 1 before forming an eyeball.
12 are provided. One scarfing machine 11 located on the left side of the drawing processes the left end side of the leaf spring 1,
The scarfing machine 12 on the right side in the figure processes the right end side of the leaf spring 1. It should be noted that the scarfing process may be performed on each side of the leaf spring 1, and in that case, one of the scarfing machines 11, 12 is sufficient.

The scarfing machines 11, 12 are symmetrical to each other and have substantially the same structure and operation.
The same reference numerals are given to the common parts, and the scarfing mechanism 11 on the left side will be described below as a representative.

As shown in FIG. 1 and FIG.
A column 16 is provided on the upper surface of the column 16, and a first guide 17 extending in the horizontal direction is provided at a vertically intermediate portion of the column 16. A second guide 18 extending in the horizontal direction is provided on the upper part of the column 16. The first guide 17 and the second guide 18 are parallel to each other.

A base unit 21 having a movable base 20 is provided on the first guide 17 so as to be reciprocally movable in the horizontal direction. The base unit 21 is driven by the ball screw mechanism 22 at a predetermined stroke in the above direction. The ball screw mechanism 22 includes a forward / reverse rotatable motor 23, a screw shaft 24 rotated by the motor 23, and a nut member (not shown) screwed to the screw shaft 24. The nut member is movable. It is provided on the base 20. Therefore, the base unit 21
Can move in the horizontal direction in the figure according to the rotation direction and the rotation amount of the screw shaft 24.

A work receiver 30 as an example of means for holding the leaf spring 1 is provided on the base unit 21 so as to be able to move up and down. The work receiver 30 supports the ends 1 a and 1 b of the leaf spring 1 before the hot-eye molding, which is heated to a hot state, and includes a support wall 31 facing the end surface of the leaf spring 1. The work receiver 30 is moved up and down by the cylinder mechanism 32, and when the work receiver 30 is raised, as shown by a two-dot chain line in FIG. , 66.

A slide unit 36 having a slide base 35 is provided above the base unit 21. The slide unit 36 is reciprocally movable in the left-right direction in the figure along the guide 18.
7 drives in the above-described direction. The ball screw mechanism 37 includes a forward / reverse rotatable motor 40, a screw shaft 41 rotated by the motor 40, a nut member 42 provided on the slide base 35, and the like. Therefore, the slide unit 36 has the screw shaft 41
Can be moved along the guide 18 according to the rotation direction and the amount of rotation.

A slider 45 is attached to the slide unit 36.
Is provided. The slider 45 is reciprocated in the horizontal direction in the figure by the rod 47 of the first cylinder mechanism 46 in the horizontal direction. Slider 45
Is provided with a horizontal second cylinder mechanism 48. A wedge-shaped cam member 50 is provided at the tip of the rod 49 of the second cylinder mechanism 48.

As shown in FIG. 3, the left and right sides of the cam member 50 have cam surfaces 55, 56 inclined in a tapered shape, and cam followers 57, 58 such as rollers contact the cam surfaces 55, 56. I have. A stopper 59 is provided in front of the cam member 50. When the rod 49 is retracted, the cam member 50 is separated from the stopper 59. As shown in FIG. 4, when the rod 49 moves forward, the cam member 50 moves to the forward position regulated by the stopper 59.

The cam followers 57, 58 are provided with links 61,
62 are provided on the bases 61a and 62a. Link 6
The heights of the tip portions 61b and 62b of the base portions 1 and 62 are
It has a shape bent downward so as to be slightly lower than 1a and 62a, and cutting blades 65 and 66 are provided near the tip portions 61b and 62b so as to face each other.

The intermediate portions in the longitudinal direction of the links 61 and 62 are supported on a substrate (not shown) by shafts 70 and 71, and the links 61 and 62 can rotate around the shafts 70 and 71 in a horizontal plane, respectively. It has become. Link 61,
The cam followers 57 and 58 are biased by the elastic force of the return spring 72 in a direction in which the cam followers 57 and 58 come into contact with the cam surfaces 55 and 56.

The cutting blades 65 and 66 move when the links 61 and 62 rotate from the position shown in FIG. 3 to the position shown in FIG.
Both edges of the end portion 1a of the leaf spring 1, that is, portions 75 and 76 to be scarfed (regions hatched in FIG. 3) are pressed so as to sandwich cutting start points 75a and 76a from both sides. In FIG. 4, the smaller the distance L between the cutting edges of the cutting blades 65 and 66 is, the smaller the part 7 to be scarfed is.
The cutting blades 65 and 66 are greatly cut into 5,76. Therefore, the cutting allowance depends on the amount of advance of the cam member 50. In other words, the length of the stopper 59 (the cam member 50)
By changing the position of the surface facing the
It is possible to adjust the cutting allowance by 5,66.

When the rod 47 of the first cylinder mechanism 46 is retracted, the cutting blades 65 and 66 move toward the plate end of the leaf spring 1 together with the slider 45 and the links 61 and 62. Therefore, the first cylinder mechanism 46 includes the cutting blades 65, 6
Drive means for moving the plate spring 6 in the longitudinal direction of the leaf spring 1 is constituted.

As shown in FIG. 5, the parts 75 and 76 to be scarfed are viewed from the front of the leaf spring 1.
Each is cut off on a plane inclined at an angle θ. That is, in this case, the cutting surfaces of the cutting blades 65 and 66 are respectively set to the angle θ so that the width B1 of the surface inside the winding when winding the eyeball is smaller than the width B2 of the surface outside the winding. Just tilted.

The reason why such an angle θ is provided is that, as described above, the material width changes between the inside and outside of the winding when the eyeball is wound. That is, if the material width B1 of the surface on the inner side of the winding is made narrower in advance than the material width B2 of the surface on the outer side of the winding, the end faces 2c and 2d in the eyeball width direction after the eyeball molding are aligned with the axis O of the eyeball 2. To the vertical. The cutting blades 65 and 66 are attached to the blade base by an appropriate angle adjusting mechanism so that the angle θ of the blade surface can be changed. The value of θ is determined in advance so that the end faces 2 c and 2 d in the eyeball width direction after the eyeball molding are close to being perpendicular to the axis O of the eyeball 2.
And the sheet thickness t and the sheet width B.

Next, the operation of the above embodiment apparatus 10 will be described. In a state where the work receivers 30 and 30 are lowered, the leaf spring 1 heated to the hot state is
Supplied on top of 30. Since the length of the leaf spring 1 varies depending on the type, the positions of the base units 21 and 21 are adjusted in advance by the ball screw mechanisms 22 and 22 according to the length of the leaf spring 1. Also, the slide units 36, 36
The cutting blade 6 is located immediately above the cutting start points 75a and 76a of the leaf spring 1.
The ball screw mechanisms 37, 37 are adjusted in accordance with the length of the leaf spring 1 so that 5, 66 cutting edges are located.

The work receivers 30, 30 are raised by the cylinder mechanisms 32, 32 of the base units 21, 21, and the leaf spring 1 is raised to the height of the cutting blades 65, 66.
At this time, the cutting edges of the cutting blades 65 and 66 face the cutting start points 75a and 76a of the leaf spring 1.

Next, when the rod 49 of the cylinder mechanism 48 operates to the extension side, the cutting blades 65 and 66 are strongly pressed so as to bite into the cutting start points 75a and 76a. In this state, the rod 47 of the first cylinder mechanism 46
The slider 45 moves in the direction of the plate end of the leaf spring 1 due to the movement of the blade toward the contraction side.
Move into the leaf end of the leaf spring 1 while biting into the leaf spring 1. Thus, the site 7 to be scarfed
5,76 is stripped off. FIG. 4 shows a state during the process.

After the above-described scarfing process is performed, the work receivers 30, 30 are lowered and the leaf spring 1 is taken out by moving the cylinder mechanism 32 to the contraction side. The extracted leaf spring 1 is sent to an eyeball processing machine (not shown), and both ends 1a and 1b of the leaf spring 1 are wound and formed into a predetermined eyeball shape.

At the time of the entanglement winding forming performed by the above-mentioned centering machine, the apparatus 10 of the present embodiment is used in advance.
Since the width of the material at the portion inside the winding is cut off so as to be smaller than the width of the material at the portion outside the winding, the width of the eyeball after the winding is prevented from exceeding the allowable value. It can be securely attached to a bracket or the like of a vehicle body. Moreover, since the end faces 2c and 2d in the eyeball width direction can be made to approach perpendicular to the axis O of the eyeball, even if a grinding operation is performed by a grinding stone in a later process for finishing,
The grinding allowance is very small. For this reason, the grinding time by the grindstone was greatly reduced, and the grinding operation could be processed in the line, and the required man-hours could be greatly reduced. In some cases, it is possible to omit the finish grinding using a grindstone.

The scarfing apparatus 10 of the present embodiment
Since the two end portions 1a and 1b of the leaf spring 1 are simultaneously processed by the pair of scarfing machines 11 and 12, the work efficiency is high. Further, since both ends 1a and 1b of the leaf spring 1 are simultaneously scarfed in the opposite directions, the tensile force applied in the longitudinal direction of the leaf spring 1 when the cutting blades 65 and 66 move in the opposite directions is canceled. It is possible to prevent an excessive tensile force from acting only in one direction of the leaf spring 1. When the scarfing is performed on each side of the leaf spring 1, since the leaf end surface of the leaf spring 1 is supported by the support wall 31 of the work receiver 30, the force acting in the longitudinal direction of the leaf spring 1 can be received. .

The device of the present invention can be applied to, for example, scarfing a desired portion of a flat steel spring, in addition to the above-described scarfing of the centerpiece forming portion.

[0031]

According to the present invention, the center of the leaf spring is wound.
A part of the meat on both sides of the predetermined area to be formed can be cut off in the longitudinal direction, and by mainly cutting off the inside of the winding in this eye forming part, the width of the eye after winding is reduced. Exceeding the allowable value can be prevented. According to the method of the present invention, finish grinding using a grindstone or the like performed after eyeball molding can be significantly reduced or omitted.

[Brief description of the drawings]

FIG. 1 is a side view of a scarfing device according to an embodiment of the present invention.

FIG. 2 is an enlarged view of a part of the scarfing device shown in FIG.

FIG. 3 is a plan view schematically showing a structure near a cutting blade in the apparatus shown in FIG.

FIG. 4 is a plan view showing an operation mode of a cutting blade in the apparatus shown in FIG.

FIG. 5 is a front view partially showing a relationship between a cutting blade and a leaf spring in the apparatus shown in FIG. 1;

FIG. 6 is a perspective view showing a part of a leaf spring having an eyeball.

FIG. 7 is a cross-sectional view schematically showing the shape of a conventional eyeball after being wound.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Leaf spring, 2 ... Eyeball, 10 ... Scarfing device, 1
1, 12: a scarfing machine, 46: a cylinder mechanism (drive means), 65, 66: a cutting blade.

Claims (2)

(57) [Claims] 1. A means for holding a leaf spring before forming an eyeball, wherein a portion of the leaf spring to be wound around the eyeball from both sides and the width of the inside of the winding is larger than the width of the area outside the winding. A pair of cutting blades arranged at an angle so as to be narrower, and a drive for moving the pair of cutting blades in the longitudinal direction of the leaf spring over an area where an eyeball is to be wound in a state where the pair of cutting blades is applied to the above-described portion of the leaf spring. Means for scarfing a leaf spring. 2. An end portion of a leaf spring before forming an eyeball is preliminarily subjected to a scarfing process so that a material width of a region inside the winding at the time of forming the eyeball is smaller than a material width of a region outside the winding. Then, an eyeball is formed by winding the leaf spring end into a predetermined shape to form an eyeball.