JPS6136818Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a combination structure of a leaf spring and a spring seat, and more particularly to a combination structure optimal for suspending an axle housing in an automobile suspension.

In the case of automobile leaf springs made of multiple leaf springs stacked one on top of the other, a bolt is passed through the center. This bolt (a) fixes multiple leaf spring materials as a spring assembly, and (b) prevents misalignment between the axle housing and the leaf spring due to longitudinal and lateral forces acting on the axle housing. (c) Positioning when assembling the axle housing to the leaf spring,
Performs functions such as A nut is generally screwed into the bolt and tightened. The leaf spring assembled in this way is connected to the axle housing with the spring seat interposed, and in this case, the bolts (b) and
In order to fulfill the function (c), the spring seat is provided with a hole for receiving the bolt head or nut.

By the way, bolt heads and nuts generally have a tool engaging part with a hexagonal profile concentric with the screw for engaging a tool such as a spanner;
The holes in the spring seat are generally round holes because the rotational position after tightening the bolt or nut is not constant. Moreover, the round hole is formed to have a larger diameter than the tool engaging portion in consideration of machining and assembly errors, and in the assembled state, there is a gap between the tool engaging portion and the hole wall surface.
Therefore, during use, the forces acting on the axle housing in the longitudinal and lateral directions cause relative movement between the axle housing and the leaf spring, causing the spring seat and the tool engaging part to come into contact with each other, causing the spring of the tool engaging part to come into contact with each other. Depending on the rotational position relative to the seat, a rotational moment is applied to the tool engaging portion, which may cause the bolt to loosen or be tightened, making it difficult to maintain a constant axial force applied to the bolt.

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a combination structure of a leaf spring and a spring seat configured to maintain a constant axial force of a bolt.

The present invention is a combination structure of a leaf spring including a leaf spring, a bolt passing through the leaf spring, and a nut screwed into the bolt, and a spring sheet superimposed on the leaf spring. The head of the bolt or the nut protruding from the leaf spring toward the spring seat has a rectangular outline and engages with a tool engaging portion provided concentrically with respect to the thread of the bolt or nut. a cylindrical part protruding from the part in the axial direction of the screw and provided concentrically with respect to the screw, the spring seat having a first hole for receiving the tool engaging part;
a second hole that receives the cylindrical portion and is arranged concentrically with respect to the hole, and the distance between the hole wall surface of the second hole and the outer circumferential surface of the cylindrical portion is equal to the distance between the hole wall surface of the second hole and the outer peripheral surface of the cylindrical portion. The distance is smaller than the distance between the hole wall surface of the hole and the edge of the tool engaging portion.

Embodiments of the present invention will be described below with reference to the drawings.

As shown in FIG. 1, the present invention has a structure in which a leaf spring 10 including a bolt 12 and a nut 14 is combined with a spring seat 16.

In the illustrated example, the leaf spring 10 is constructed by stacking three leaf springs 18, and a bolt 12 passes through the center thereof. A nut 14 is screwed into this bolt 12 to fix the three leaf springs 18 as an assembly. A clip 20 and an auxiliary clip 22 are attached to the leaf spring 10,
The leaf spring 10 is connected to the vehicle body by eyes 24 provided at both ends thereof.

As shown in FIGS. 2 and 3, the nut 14 is
A tool engaging portion 28 provided concentrically with respect to the screw 26, that is, formed symmetrically with respect to the axis of the screw, and having a hexagonal outline; Screw 26 from engagement part 28
It has a cylindrical portion 30 that protrudes in the axial direction of the screw and is formed concentrically with the screw. A screw 26 is provided on the inner peripheral surface of this cylindrical portion 30. Therefore, the axial force applied to the bolt can also be borne by the thread of the cylindrical portion 30, which is preferable.

The spring sheet 16 is superimposed on the upper side of the leaf spring 10 and has a first hole 32 that receives the tool engaging portion 28 of the nut 14, is arranged concentrically with this hole 32, and is connected to the first hole 32. It has a second hole 34 opened therein. The second hole 34 receives the cylindrical portion 30 of the nut 14. First hole 32
and the second hole 34 means that the distance A between the hole wall surface of the second hole 34 and the outer peripheral surface of the cylindrical portion 30 is the same as that of the first hole 32.
Each of the holes has a diameter smaller than the distance B between the hole wall surface and the edge of the tool engaging portion 28 . The spring seat 16 is integrally provided with catch seats 36 on both sides in the width direction of the vehicle body, and the catch seats 36 are connected to the axle housing 38.
be welded to.

Leaf spring 10 and axle housing 3
8, insert and position the tool engaging part 28 and cylindrical part 30 of the nut 14 into the first hole 32 and second hole 34 of the spring seat 16, respectively, and then A pair of U-bolts 40 placed at a distance are guided to the underside of the leaf spring 10, penetrated through the U-bolt seat 42 applied to the lower surface of the leaf spring 10, and the U-bolts 40
Screw the nut 44 onto the end of the screw and tighten.

When a relative movement occurs between the leaf spring 10 and the axle housing 38 during use, the hole wall surface of the second hole 34 of the spring seat 16 abuts against the outer peripheral surface of the cylindrical portion 30 of the nut 14, and the relative movement is suppressed. In this case, as a result of the size relationship of the intervals as described above, the hole wall surface of the first hole 32 does not abut against the edge of the tool engaging portion 28, so that the nut 1
4. Loosening or retightening will not occur.

In the above example, the nut is provided with a cylindrical portion, but
Alternatively, the head 13 of the bolt 12 may be provided with a cylindrical portion. That is, when the bolt 12 is passed through the leaf spring 10 so that the head 13 protrudes from the leaf spring 10 toward the spring seat 16, the head 13 does not fit into a tool engaging portion having a hexagonal or other rectangular outline. If the head 13 has a cylindrical portion, the above problem can be solved.

According to the present invention, even if relative movement occurs between the axle housing and the leaf spring due to forces in the longitudinal and lateral directions applied to the axle housing,
This movement is inhibited by the abutment between the hole in the spring seat and the cylindrical portion provided on the head of the bolt or nut, and the tool engaging portion of the bolt or nut will not receive any rotational moment from the spring seat. Therefore, the axial force of the bolt can be maintained constant without loosening or retightening the bolt.

[Brief explanation of the drawing]

FIG. 1 is a front view showing the combined structure of the present invention, FIG. 2 is a sectional view of the main parts, and FIG. 3 is a perspective view of the nut. 10: leaf spring, 12: bolt, 1
3: Head, 14: Nut, 16: Spring seat, 2
8: Tool engaging portion, 30: Cylindrical portion, 32: First hole, 34: Second hole.

Claims (1)

[Scope of utility model registration request] A combination structure of a leaf spring including a leaf spring, a bolt passing through the leaf spring, and a nut screwed into the bolt, and a spring seat superimposed on the leaf spring, from the leaf spring to the spring seat. The head of the bolt or the nut that protrudes toward the bolt or the nut has a rectangular outline, and a tool engaging portion provided concentrically with respect to the thread of the bolt or the nut, and from the tool engaging portion to the axis of the screw. a cylindrical portion projecting in the direction and provided concentrically with respect to the screw; the spring seat having a first hole for receiving the tool engaging portion; and a cylindrical portion disposed concentrically with respect to the hole; a second hole for receiving the cylindrical portion, and a gap between the hole wall surface of the second hole and the outer circumferential surface of the cylindrical portion is between the hole wall surface of the first hole and the tool engaging portion. It is smaller than the distance between the edges. A combination structure of leaf springs and spring seats.