JP3682334B2 - Spring constant switching structure - Google Patents

Description

[0001]
[Industrial application fields]
The present invention relates to a spring constant switching structure, and more particularly to an improvement of a spring constant switching structure in a suspension spring provided in a hydraulic shock absorber mounted on a vehicle.
[0002]
[Prior art and its problems]
As is well known, for example, the spring constant of a suspension spring provided in a hydraulic shock absorber mounted on a vehicle improves the ride comfort and maneuverability of the vehicle. For example, it is preferable to switch between large and small according to the posture.
[0003]
In order to meet this demand, there have been various proposals. For example, in Japanese Patent Application Laid-Open No. 60-94810, the suspension spring is disposed so as to be movable up and down between the suspension springs. It consists of a plate and two coil springs arranged in series above and below the plate, and by selecting whether the plate can be moved up or down, one or both of the two coil springs can be selectively expanded or contracted. Therefore, a configuration has been proposed in which the spring constant of the suspension spring is switched between large and small.
[0004]
That is, in the proposal, in addition to the suspension spring, detection means connected to the plate for detecting displacement accompanying expansion and contraction of the hydraulic shock absorber, and an input signal from the detection means are subjected to arithmetic processing and the like. And a controller that selectively outputs one or both of the two coil springs via a plate by an output signal from the controller. ing.
[0005]
Therefore, in the proposal, although it is via the detection means and the controller, one or both of the two coil springs constituting the suspension spring are activated by the operation of the adjusting mechanism according to the vehicle height situation in the vehicle. Expansion and contraction is selectively enabled, that is, it becomes possible to automatically switch the spring constant of the suspension spring between large and small.
[0006]
However, in the proposal, in the configuration, in addition to the suspension spring having a plate, the detection means, the controller, and the adjustment mechanism are essential, so that the whole is a so-called overhang, for example, mounted on a vehicle. When it is attached to the hydraulic shock absorber, it is easy to deteriorate the mounting property of the hydraulic shock absorber on the vehicle, and it is difficult to reduce the cost, and it is difficult to expect improvement in its versatility. .
[0007]
In this proposal, the adjusting mechanism is a hydraulic cylinder mechanism with an on-off valve. However, since the switching operation of the on-off valve is realized instantaneously, the hydraulic pressure fluctuation in the hydraulic cylinder is instantly expressed, and this influence Is reflected in the switched spring constant of the suspension spring, and thus, for example, a problem that the feeling when improving the riding comfort and maneuverability in the vehicle is easily deteriorated is pointed out.
[0008]
Further, in order to eliminate the influence of the switching operation of the on-off valve, further control for finely switching the on-off valve is required, and as a result, the overall operation becomes even larger. In addition to facilitating the mounting on the vehicle, it causes a problem that the cost cannot be further reduced.
[0009]
The present invention was devised in view of the above-described circumstances, and the object of the present invention is to enable space saving by reducing the size as a whole and to reduce the cost. For example, it is provided in a hydraulic shock absorber. Switching the spring constant of the suspension spring to improve the riding comfort and controllability of the vehicle does not deteriorate the mountability to the vehicle, and the switching of the spring constant is automatically performed according to the vibration frequency. Further, it is to provide a spring constant switching structure which is optimal for preventing the deterioration of the feeling at that time.
[0010]
[Means for Solving the Problems]
In order to achieve the above object, one means of the present invention includes a vehicle body side suspension spring element and an axle side suspension spring element arranged in parallel with a hydraulic shock absorber, a vehicle body side suspension spring element, and an axle side suspension spring element. In the spring constant switching structure having the spring constant switching means disposed between the cylinder, the hydraulic shock absorber is connected to the cylinder body, the rod body movably inserted into the cylinder body, and the upper end of the rod body. An upper spring bearing and a lower spring bearing connected to the lower end side of the cylinder body, the spring constant switching means being fixed to the outer circumference of the cylinder body; and the outer circumference of the cylinder body and the outer circumference of the piston are slidable A cylinder member housed in the cylinder, an extension side oil chamber and a pressure side oil chamber partitioned by a piston in the cylinder member, and a flow path that is opened in the piston or rod body and communicates the extension side oil chamber and the pressure side oil chamber. , Restriction placed in the flow path Consists of a, the vehicle body-side suspension spring element is interposed between the upper spring receiver and the cylinder member, characterized in that the axle-side suspension spring element is interposed between the lower spring receiver and the cylinder member.
[0011]
Similarly, the other means includes a vehicle body side suspension spring element and an axle side suspension spring element arranged in parallel with the hydraulic shock absorber, and a spring constant switching means arranged between the vehicle body side suspension spring element and the axle side spring element. In the spring constant switching structure, the hydraulic shock absorber has a cylinder body, a rod body that is movably inserted into the cylinder body, an upper spring receiver that is connected to the upper end of the rod body, and a lower end side of the cylinder body. A piston member in which the spring constant switching means is fixed to the outer periphery of the rod body, a cylinder member slidably mounted on the outer periphery of the rod body and the outer periphery of the piston, An expansion-side oil chamber and a compression-side oil chamber that are partitioned by a piston, a flow path that is opened in the piston or rod body and communicates with the expansion-side oil chamber and the compression-side oil chamber, and a restriction disposed in the flow path. If the vehicle body side suspension spring element is An axle suspension spring element is interposed between the lower spring receiver and the cylinder member.
[0012]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, the present invention will be described with reference to the drawings. The spring constant switching structure of the present invention basically has a vehicle body side suspension spring element 1 and an axle side as shown in FIGS. The suspension spring element 2 and the spring constant switching means 3 are provided.
[0013]
In other words, the spring constant switching structure according to the embodiment shown in FIG. 1 includes the vehicle body side suspension spring element 1 and the axle side suspension spring element 2 arranged in parallel with the hydraulic shock absorber SA, the vehicle body side suspension spring element 1 and the axle. Spring constant switching means 3 disposed between the side suspension spring elements 2 is provided. The hydraulic shock absorber SA is connected to the cylinder body 4, the rod body 5 movably inserted into the cylinder body 4, an upper spring receiver 51 provided continuously with the upper end of the rod body 5, and the lower end side of the cylinder body 5. A lower spring bearing 41 provided, and a piston 34 in which the spring constant switching means 3 is fixed to the outer periphery of the cylinder body 4, and a cylinder slidably disposed on the outer periphery of the cylinder body 4 and the outer periphery of the piston body 34 The member 31, the extension side oil chamber R1 and the pressure side oil chamber R2 defined by the piston 34 in the cylinder member 31, and the piston 34 or the rod body 5 are opened to communicate the extension side oil chamber R1 and the pressure side oil chamber R2. And a throttle 33 disposed in the flow path L. The vehicle body side suspension spring element 1 is interposed between the upper spring receiver 51 and the cylinder member 31, and the axle side suspension spring element 2 is disposed. The lower spring bearing 41 and the cylinder member 31 In which is interposed between the.
[0014]
Similarly, the spring constant switching structure according to the embodiment shown in FIG. 2 includes the vehicle body side suspension spring element 1 and the axle side suspension spring element 2 arranged in parallel with the hydraulic shock absorber SA, and the vehicle body side suspension spring. The hydraulic shock absorber SA includes a cylinder body 4 and a rod that is movably inserted into the cylinder body 4. The spring constant switching means 3 is disposed between the element 1 and the axle-side spring element 2. A body 5, an upper spring receiver 51 connected to the upper end of the rod body 5, and a lower spring receiver 41 connected to the lower end side of the cylinder body 5, and the spring constant switching means is fixed to the outer periphery of the rod body 5. The provided piston 34, the cylinder member 31 slidably disposed on the outer periphery of the cylinder body 4 and the outer periphery of the piston body 34, the extension side oil chamber R1 and the pressure side oil chamber partitioned by the piston 34 in the cylinder member 31 R2 and piston 34 or rod 5 and a flow path L communicating with the extension side oil chamber R1 and the pressure side oil chamber R2, and a throttle 33 disposed in the flow path L, and the vehicle body side suspension spring element 1 is connected to the upper spring receiver 51. The axle suspension spring element 2 is interposed between the lower spring receiver 41 and the cylinder member 31.
[0015]
In each of the embodiments described above, each throttle 33 allows the hydraulic oil to pass when the vibration frequency of the cylinder body 4 or the rod body 5 in the cylinder member 31 is in the low frequency region, whereas in the cylinder member 31 When the vibration frequency of the rod member 32 is in a high frequency region, the hydraulic oil is set to be blocked.
[0016]
The phrase will be explained in detail below. FIG. 1 and FIG. 2 show an embodiment in which the above-described spring constant switching structure is embodied in a mode in which it is combined with the hydraulic shock absorber SA. In the embodiment shown in FIG. The switching means 3 is embodied in the cylinder body 4 constituting the hydraulic shock absorber SA. In the embodiment shown in FIG. 2, the spring constant switching means 3 is embodied in the rod body 5 constituting the hydraulic shock absorber SA. It is a thing.
[0017]
That is, in the embodiment shown in FIG. 1, the upper end of the vehicle body side suspension spring element 1 made of a coil spring is locked to the upper spring receiver 51 connected to the upper end of the rod body 5, and the coil spring is also the same. The lower end of the axle-side suspension spring element 2 is supported by a lower spring receiver 41 connected to the lower end side of the cylinder body 4, while the cylinder member 31 constituting the spring constant switching means 3 is disposed on the outer periphery of the cylinder body 4. It is assumed that it is slidably held.
[0018]
The cylinder member 31 carries the lower end of the vehicle body side suspension spring element 1 at the upper end and the upper end of the axle side suspension spring element 2 is engaged with the lower end. It has been replaced by.
[0019]
Further, in this case, it is assumed that the piston 34 that partitions the expansion side oil chamber R1 and the pressure side oil chamber R2 is fixedly provided on the outer periphery of the cylinder body 4 in the cylinder member 31, and the throttle 33 is disposed on the piston 34. ing.
[0020]
When the vibration frequency is in the low frequency region, the restrictor 33 allows the hydraulic oil to pass, so that the expansion side oil chamber R1 and the pressure side oil chamber R2 can be widened and the cylinder member 31 slides. The spring constant switching means 3 can be expanded and contracted.
[0021]
Accordingly, the vehicle body side suspension spring element 1 connected to the cylinder member 31 can be expanded and contracted. As a result, the vehicle body side suspension spring element 1 and the axle side suspension spring element 2 are expanded and contracted, respectively. The spring constant of the suspension spring composed of the suspension spring element 1 and the axle-side suspension spring element 2 is small.
[0022]
On the other hand, when the vibration frequency is in the high frequency range, the throttle 33 prevents the hydraulic oil from passing through. Therefore, the expansion-side oil chamber R1 and the compression-side oil chamber R2 cannot be widened and the cylinder member 31 does not slide. The expansion and contraction of the spring constant switching means 3 becomes impossible.
[0023]
At this time, by making the spring constant switching means 3 inextensible or non-extensible, that is, by making it into a block, only the axle-side suspension spring element 2 can be expanded and contracted. As a result, the spring constant of the suspension spring is increased. Become.
[0024]
Therefore, according to the switching structure of the spring constant described above, for example, when the vehicle travels on a paved road surface with a large undulation at a relatively low speed tendency, the load changing speed, that is, the flow speed of the hydraulic oil is small. Since the vibration frequency is also in the low frequency region, the spring constant switching means 3 can be expanded and contracted. As a result, the spring constant becomes small and the riding comfort in the vehicle is improved.
[0025]
Also, for example, when the vehicle travels on a road surface with continuous fine irregularities at a relatively high speed, the load changing speed, that is, the flow rate of hydraulic oil is large, and the vibration frequency is in the high frequency range. The expansion and contraction of the spring constant switching means 3 is disabled, and as a result, the spring constant becomes large and the maneuverability in the vehicle is improved.
[0026]
According to the above-described spring constant switching structure, the timing of switching the magnitude of the spring constant depends on the setting of the restrictor 33, for example, when the restrictor 33 comprises an orifice, the setting of the diameter of the orifice, When the throttle 33 is variable, the spring constant of the suspension spring is arbitrarily increased or decreased according to the situation of the vehicle traveling on an arbitrary road surface by forcibly changing the flow rate of hydraulic oil by an appropriate means. It becomes possible to switch to.
[0027]
Further, depending on the setting of the throttle 33, the possibility of passage of hydraulic oil through the throttle 33, that is, the possibility of expansion and contraction of the spring constant switching means 3 decreases with an increase in the vibration frequency. It is possible to prevent sudden expansion / contraction, and no shock is caused when switching the spring constant between large and small, resulting in deterioration of feeling when improving riding comfort and maneuverability in the vehicle. It is possible not to let it.
[0028]
In the embodiment of FIG. 1, since the spring constant switching means 3 is provided integrally with the hydraulic shock absorber SA, so-called compactness is possible, and space-saving improves the mountability to the vehicle. It will be.
[0029]
On the other hand, in the embodiment shown in FIG. 2, the upper end of the vehicle body side suspension spring element 1 formed of a coil spring is locked to the upper spring receiver 51 connected to the upper end of the rod body 5, and the coil spring is also the same. The lower end of the axle-side suspension spring element 2 is carried by a lower spring receiver 41 connected to the lower end side of the cylinder body 4, while the cylinder member 31 constituting the spring constant switching means 3 is disposed on the outer periphery of the rod body 5. It is assumed that it is slidably held.
[0030]
Then, the cylinder member 31 supports the lower end of the vehicle body side suspension spring element 1 with the spring receiving portion 31a formed on the outer periphery and engages the upper end of the axle side suspension spring element 2, so that the rod body 5 is a double rod type. It is assumed that the rod member 32 is substituted.
[0031]
Further, in this case, it is assumed that the piston 34 that partitions the expansion side oil chamber R1 and the pressure side oil chamber R2 is fixed to the outer periphery of the rod body 5 in the cylinder member 31, and the throttle 33 is arranged on the piston 34. It is supposed to become.
[0032]
Therefore, in this embodiment, the spring constant switching means 3 is provided integrally with the hydraulic shock absorber SA, so that so-called downsizing is possible. Since the position is the rod body 5 portion in the hydraulic shock absorber SA, it is possible to further reduce the space and further mountability to the vehicle as compared with the embodiment shown in FIG. Will be improved. The effect of the aperture 33 is the same as in the embodiment of FIG.
[0033]
In FIG. 3, the spring constant switching means 3 is embodied in the rod body 5 portion of the hydraulic shock absorber SA (see FIG. 2), the throttle 33 is variable, and the variable throttle 33 is rod body. 5 shows a specific embodiment in the case where it is distributed within 5, and in the following, this embodiment will be described a little.
[0034]
First, the cylinder member 31 constituting the spring constant switching means 3 is slidably interposed on the outer periphery of the rod body 5, and the piston 34 fixed on the outer periphery of the rod body 5 is accommodated in the cylinder member 31. The piston 34 partitions the expansion side oil chamber R1 and the pressure side oil chamber R2 in the cylinder member 31.
[0035]
The extension side oil chamber R1 and the pressure side oil chamber R2 can communicate with each other by a flow path L opened in the rod body 5, and a rotary valve 52 can be rotated in the flow path L. The rotation of the rotary valve 52 allows the rotary valve 52 to communicate with each other through a selected one of a plurality of throttle holes 52a and 52b having different opening and closing channel areas. Yes.
[0036]
In addition, a control rod 53 is connected to the rotary valve 52, and an upper end of the control rod 53 is connected to a drive actuator 55 disposed inside a bracket 54 that is connected to the upper end of the rod body 5.
[0037]
The control rod 53 is disposed on the shaft core portion from the upper end to the lower side of the rod body 5 with a spacer 56 and a seal 57 interposed therebetween.
[0038]
Although not shown, between the cylinder member 31 and the upper spring receiver 51 connected to the upper end of the rod body 5 and between the cylinder member 31 and the lower spring receiver 41 connected to the lower end side of the cylinder body 4. Of course, the vehicle body side suspension spring element 1 and the axle side suspension spring element 2 are interposed.
[0039]
Therefore, in this embodiment, the spring constant switching means 3 is the rod body 5 portion in the hydraulic shock absorber SA, so that the above-described compactness and space saving can be achieved. By making the diaphragm 33 for switching the spring constant variable, the spring constant of the suspension spring can be arbitrarily switched between large and small according to the situation of the vehicle traveling on an arbitrary road surface.
[0040]
【The invention's effect】
As described above, according to the present invention, since the spring constant switching means is provided integrally with the cylinder body or the rod body of the hydraulic shock absorber, so-called compactness is possible, and space saving can be achieved. The mountability will be improved.
Similarly, since the spring constant switching structure includes spring constant switching means that enables expansion and contraction between the vehicle body side suspension spring element and the axle side suspension spring element, no other configuration is required. As a result, it is possible to switch the spring constant between large and small, and therefore, it becomes possible to save space by reducing the size and reduce the cost as a whole.
[0041]
At this time, since the spring constant switching means is configured to enable or disable expansion / contraction by the diaphragm effect by the diaphragm, for example, when the diaphragm diameter is set, or when the diaphragm is set to a variable type In addition, the switching timing of the spring constant can be arbitrarily set by, for example, forcibly changing the flow rate of the hydraulic oil by an appropriate means.
[0042]
In particular, whether or not the hydraulic oil can pass through the throttle, that is, whether or not the expansion and contraction of the spring constant switching means decreases with an increase in the vibration frequency, suddenly expresses whether or not the spring constant switching means can expand and contract. Thus, when the spring constant is switched between large and small, no shock is caused, and there is no concern about the deterioration of the feeling when improving the riding comfort and maneuverability of the vehicle.
[0043]
As a result, according to the present invention, it is possible to save space by reducing the size as a whole and to reduce the cost, and in the case of traveling on a paved road surface having a large undulation at a relatively low speed tendency, Decreasing the spring constant in the spring improves the ride comfort in the vehicle, and increases the spring constant in the suspension spring when the vehicle is traveling at a relatively high speed on a road surface with continuous fine irregularities. Further, there is an advantage that the timing of switching the spring constant at that time is automatically set, and the switching is not suddenly realized, so that the feeling is not deteriorated.
[Brief description of the drawings]
FIG. 1 is a longitudinal front view of a spring constant switching structure according to an embodiment of the present invention.
FIG. 2 is a longitudinal front view of a spring constant switching structure according to another embodiment.
FIG. 3 is a longitudinal front view of a spring constant switching structure according to another embodiment.
[Explanation of symbols]
SA Hydraulic shock absorber 1 Car body side suspension spring element 2 Axle side suspension spring element 3 Spring constant switching means 4 Cylinder body 4
5 Rod body 5
51 Upper spring holder 51
41 Lower spring support 41
33 Aperture 34 Piston 34
31 Cylinder member 31
R1 Extension side oil chamber R1
R2 Pressure side oil chamber R2
L Flow path L

Claims (2)

  A spring constant comprising: a vehicle body side suspension spring element and an axle side suspension spring element arranged in parallel with the hydraulic shock absorber; and a spring constant switching means arranged between the vehicle body side suspension spring element and the axle side suspension spring element. In this switching structure, the hydraulic shock absorber includes a cylinder body, a rod body movably inserted into the cylinder body, an upper spring receiver connected to the upper end of the rod body, and a lower spring receiver connected to the lower end side of the cylinder body. A piston fixed to the outer periphery of the cylinder body, a cylinder member slidably disposed on the outer periphery of the cylinder body and the outer periphery of the piston, and the piston separated in the cylinder member A vehicle body side suspension spring comprising an extension side oil chamber and a pressure side oil chamber, a flow path that is opened in the piston or rod body and communicates with the extension side oil chamber and the pressure side oil chamber, and a throttle disposed in the flow path. The upper spring support and the element It is interposed between the cylinder member, the switching structure of the spring constant, characterized in that interposed between the axle-side suspension spring element and the lower spring receiver and the cylinder member   A spring constant comprising a vehicle body side suspension spring element and an axle side suspension spring element arranged in parallel with the hydraulic shock absorber, and a spring constant switching means arranged between the vehicle body side suspension spring element and the axle side spring element. In the switching structure, the hydraulic shock absorber includes a cylinder body, a rod body that is movably inserted into the cylinder body, an upper spring receiver that is connected to the upper end of the rod body, and a lower spring receiver that is connected to the lower end side of the cylinder body. A piston fixed to the outer periphery of the rod body, a cylinder member slidably mounted on the outer periphery of the rod body and the outer periphery of the piston, and an extension defined by the piston in the cylinder member. A vehicle body side suspension spring element comprising a side oil chamber and a pressure side oil chamber, a flow path opened in the piston or rod body and communicating with the expansion side oil chamber and the pressure side oil chamber, and a throttle disposed in the flow path. The upper spring support and the cylinder Is interposed between the timber 3, the switching structure of the spring constant, characterized in that interposed between the axle-side suspension spring element and the lower spring receiver and the cylinder member

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