JPH048005Y2 - - Google Patents

Description

[Detailed Description of the Invention] (Technical Field of the Invention) The present invention relates to an air spring, and particularly relates to an air spring provided with a diaphragm called a rolling diaphragm.

(Prior Art) Air springs for strut-type suspensions of automobiles are formed by spanning a diaphragm between a housing fixed to the piston rod of a shock absorber and a cylinder, which is an air piston.
When the shock absorber expands and contracts during rebound or bounce, the diaphragm deforms in a wave-like manner, which is why it is called a rolling diaphragm.
This rolling diaphragm has a large hysteresis during deformation, which adversely affects riding comfort, and the deformable range, that is, the range in which it can follow the stroke of the shock absorber, is relatively small.

(Object of the invention) Therefore, an object of the invention is to obtain an air spring equipped with a rolling diaphragm that can reduce hysteresis and increase the deformable range.

(Structure of the invention) The present invention has an elastic means that spans a housing and an air piston that is disposed at a distance from the housing and is supported so as to be movable in the axial direction of the piston rod with the piston rod of the shock absorber as an axis. a chamber-forming air spring, the elastic means comprising a first diaphragm with a collar fixed at an upper end to the housing, and a bolted first diaphragm fixed at a lower end to the air piston; a cylindrical member interposed between the first diaphragm and the second diaphragm, the lower end of which is located at the lower end of the first diaphragm; and cylindrical members respectively fixed at the upper ends thereof.

(Example) Examples of the present invention will be described below with reference to the drawings.

In the illustrated example, the air spring 10 is provided at the upper end of the shock absorber 12, forming a strut-type suspension. The air spring 10 includes a housing 14, an air piston 16, and elastic means 18, and has an air chamber 20 surrounded by these.

The shock absorber 12 comprises a cylinder, a piston slidably disposed within the cylinder, and a piston rod 22 connected at one end to the piston and projecting outwardly from the cylinder at the other end. The piston is provided with a valve through which oil or other liquid contained within the cylinder flows when the piston rod 22 is extended and retracted. Since the above configuration is well known, illustration thereof is omitted. As the shock absorber 12, in addition to the so-called twin tube type, which includes an inner shell and an outer cylinder, a so-called monotube type, which consists of only a single cylinder, is used.
In the illustrated example, the cylinder constitutes the air piston 16, and the piston rod 22 is connected to the support 2.
1 to the vehicle body 23.

The housing 14 includes a circular fixing plate 26 held between a mounting ring 24 welded to the piston rod 22 and an inner member of the support 21 pressed by a nut 25 screwed to the piston rod 22, and a circular fixing plate 26 that is entirely attached to the fixing plate 26. A flange portion 27 welded around the circumference, a first cylindrical portion 28 extending downward from the flange portion 27, and a second cylindrical portion having a small diameter extending downward from the cylindrical portion via a tapered inclined portion. 29.

In the above example, the air piston 16 is the cylinder of the shock absorber 12, but in order to increase the effective diameter of the air spring, a cylindrical member may be welded to the cylinder and this cylindrical member may be used as an air piston. The air piston 16 is spaced from the housing 14 and supported so as to be movable about the piston rod 22 in the axial direction of the piston rod.

The elastic means 18 includes a first diaphragm 30 which is made of rubber and has a cylindrical groove, and a second diaphragm 32 which is also made of rubber and has a cylindrical groove. and a cylindrical member 34 interposed between the diaphragms.

In the illustrated example, the cylindrical member 34 has an upper end 36 bent radially inward and a lower end 37 bent radially outward. According to this structure of the cylindrical member, when the cylindrical member 34 and the first and second diaphragms 30, 32 are connected as described later, the chances that the joints and loose portions of both diaphragms come into contact with the cylindrical member are reduced. , there is no resistance when the shock absorber expands and contracts, and wear or damage to the diaphragm can be prevented. The cylindrical member 34 is made of iron, fiber-reinforced plastic, or the like.

The upper end 38 of the first diaphragm 30 is sandwiched between the cylindrical portion 29 of the housing 14 and the ring 40, and the upper end 38 is fixed to the housing 14 by caulking the ring 40. And the first
The lower end 39 of the diaphragm 30 of the cylinder member 3
The lower end 39 is fixed to the cylindrical member 34 by sandwiching the ring 42 between the lower end 37 and the ring 42 and caulking the ring 42. On the other hand, the upper end 44 of the second diaphragm 32 is brought to the outside of the upper end 36 of the cylindrical member 34, and is sandwiched between the end 36 and the ring 46, and the ring 46 is caulked to form the upper end. 44 is fixed to the cylindrical member 34. The lower end 45 of the second diaphragm 32 is sandwiched between the air piston 16 and the ring 46, and the ring 46 is caulked to fix the lower end 45 to the air piston 16. As a result, an air chamber 20 is formed by the cooperation of the housing 14, the air piston 16, and the elastic means 18.

(Effects of the invention) According to the invention, since the first and second diaphragms provided in the elastic means of the air spring have ribs, the ribs expand or contract when the shock absorber expands or contracts. , follows the expansion and contraction of the shock absorber and reduces hysteresis.
As a result, riding comfort can be improved. Further, since the elastic means includes two diaphragms and a cylindrical member interposed between these diaphragms, the deformable range is increased and it can follow a large stroke of the shock absorber.

[Brief explanation of the drawing]

The figure is a sectional view showing the air spring according to the present invention installed in a shock absorber. 10... Air spring, 12... Shock absorber, 14... Housing, 16... Air piston, 18... Elastic means, 20... Air chamber, 30...
...First diaphragm, 32... Second diaphragm, 34... Cylindrical member.

Claims (1)

[Scope of utility model registration request] An air spring in which an air chamber is formed by extending an elastic means between a housing and an air piston which is disposed at a distance from the housing and is supported so as to be movable in the axial direction of the piston rod with the piston rod of the shock absorber as an axis. The elastic means includes a first diaphragm with a groove fixed to the housing at an upper end, and a second diaphragm with a groove fixed to the air piston at a lower end. , a cylindrical member interposed between the first and second diaphragms, with a lower end at the lower end of the first diaphragm and an upper end at the upper end of the second diaphragm; and cylindrical members each secured at an end.