JPH05508903A - Suspension system and its spring elements - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed description of the invention] Suspension system and its spring elements OmegaΩ and 3 In its broadest sense, the present invention provides a substantially constant spring force when the element is deformed during use. This relates to a spring element that can give This also works like above Suspension device including a spring element to oppose displacement of one part relative to another part It is possible to provide a constant or substantially constant force that This relates to a suspension system in which the force is adjustable.

The present invention has been developed in connection with vehicle suspension systems.

When the term "vehicle" is used here, it includes passenger cars, trailers and semi-trailers. means to include, but not necessarily be limited to, all types of commercial motor vehicles; Not done. The invention also relates more generally to, for example, parts or assemblies of equipment. said parts or assemblies so as to isolate them from movements or vibrations that affect other parts; Also applicable to plant or equipment where suspension systems are required to support the body. It is possible.

Regular springs, such as coil springs or leaf springs, used in vehicle suspension systems is the relative to the vehicle's spring support structure caused by the motion of the vehicle's wheels. A spring exerts a force to resist deformation, but this force increases with such deformation. come. Does this force increase linearly with spring deformation? '') or increases more rapidly with the deformation of the spring (called ``increasing rate spring action''). call). In vehicle suspension systems involving conventional spring means, the selection of spring characteristics is always , the requirement to provide good riding comfort to vehicle passengers and the safety that vehicles should satisfy. The requirement is to provide stability and maneuverability, as well as the ability to provide a wide range of loading conditions. Compromises are made between demands. When considering vehicle running on irregular surfaces, it is important to consider Assuming no slope, the magnitude of the surface irregularity is determined by the vehicle suspension system. Assuming the range of wheel movement provided is not exceeded, the vehicle's spring structure If the wheels of a vehicle can follow irregular surfaces while following the road, theoretically preferable. Ideally, the spring means used within the suspension system will It is required not to increase or decrease the holding force, which allows the vehicle to fluctuate from its flat run. It never happens. This would be called a constant force (zero rate) spring device. however, Such spring devices themselves do not ensure the vehicle riding height and are not suitable for loading and dynamic conditions. If the conditions are different, the vehicle attitude and stability cannot be maintained.

Thus, while providing a constant or near-constant spring force (zero rate or near-zero rate), so that the force can be controlled to stabilize the vehicle even when driving conditions change. It is preferred to provide a vehicle suspension with spring means that is adjustable. stomach. Such a preferred device is also applicable to other use embodiments of the invention. child It is an object of the present invention to provide a suspension system and a spring element for the suspension system. It is a purpose.

According to one aspect of the invention, the actuation between two relatively movable parts allows the a spring element for changing the distance between said two elements, said element having an elongated shape; have an end section designed to connect to the parts, thereby allowing these parts to The elements tend to take on a progressively more buckled shape when moved in directions facing each other. the shape of said element is the same as its surface when this element is thus deformed. such as to provide substantially uniform stress on the surface and between said two portions. a substantially constant force is exerted on said part by said element during said relative movement; A spring element is provided.

The spring element according to the invention has a medium that lies in a single plane when the spring element is buckled. Preferably, it is in the form of an elongated strip of material with a core. the element is transformed In order to achieve the required uniform stress within the surface of this element when For constant thickness, the amount of material within the width dimension of the element (where dimension is the strip (meaning the dimension perpendicular to the plane occupied by the center line of the or varying from a minimum value adjacent to its ends to a maximum value midway between its ends Must.

The thickness of an element is the dimension parallel to the plane in which the centerline of the buckled element lies. Ru.

The required distribution of material within an element of constant thickness achieves conditions of uniform stress within its surface. In order to It is defined by Eq.

Here, L is the total length of the undeformed element, and WO is the center point between the ends of the element. W is the width of the element at distance X from the center point of the element, R is the maximum width of the element This is the radius of curvature when bent to the maximum deformation state.

The spring element is preferably moon-shaped, but along its length For example, if the moon-shaped element has parallel outer sides, It is also well known that the distribution of material is achieved by a cut section approximately resembling a moon-shaped shape between the stomach.

Use metal or composite material (fiber-reinforced plastic) as the spring material. Can be done.

The ends of the spring element may be pivotally connected to two relatively movable parts. Ta For example, both ends of the spring element can be provided with an abutment surface for abutting the movable part. Wear.

According to another aspect of the invention, a suspension for suspending a first member relative to a second member. Apparatus for constraining a first member to a desired path of relative movement with respect to a second member. means and Spring means arranged between two parts attached to said member, one part being The distance between said two parts changes when moving relative to the other part, and the front The spring means maintains a substantially uniform force between the parts when the parts are in relative motion with respect to each other. at least one spring element connected to said portion to provide a constant force. and the at least one spring element and at least one of said members. means for changing the force exerted between members by spring means by changing the geometrical relationship; A suspension system is provided that includes:

the or each spring element being according to the first aspect of the invention as described above; applying a force that forces said parts apart from each other so that they are deformed into said buckled shape; buckling increases as the parts move towards each other It is preferable that it is connected to the part so as to do so. Said in geometry Preferably, the changes include small changes.

As noted above, the present invention has been devised in connection with a vehicle suspension system. therefore, According to another aspect of the invention, the wheel carrier member is moved relative to the vehicle structure. means for restraining the wheel carrier to a generally vertical required path and the wheel carrier relative to the vehicle structure. The two parts are arranged so that the distance between them decreases when moving relatively upwards. spring means disposed between portions of the vehicle suspension system, the spring means comprising: comprises at least one spring element according to the first aspect of the invention as described above; moving said parts away from each other such that both ends of the element are deformed into said buckled shape; and when said parts move in a direction opposite to each other said at least one pivot connected such that buckling increases at said at least one At least one connection position of said portion of the elongated element is adapted to lock the wheel by spring means. Vehicle suspension that is adjustable to vary the force supported on the carrier member. A racking device is provided.

In the vehicle suspension system according to the invention, at least one extension constituting the spring means Such a shape of the element provides a substantially constant spring force (zero rate). whee By adjusting the connection position of the spring means (eventually the force generated on the carrier member (by adjusting the leverage between the eel carrier member and the spring means) , the suspension system is controlled to stabilize the vehicle under different loading and dynamic conditions. It is possible.

Particularly in the vehicle suspension system according to the invention, the To adjust the connection position of the end of the elongated element(s) in order to vary the force. Control equipment shall be provided to operate appropriate means for this purpose. This results in , the vehicle suspension system responds to surface irregularities such as the front suspension around a suitable average position. I'm sure it will work. For example, actuation of such a control device depends on its load. Consideration may be given to the vehicle in the rest position where the weight is increased. of the vehicle As the load on the wheel increases, the spring force in the suspension system causes the wheel to strain. exceeds the force exerted on the vehicle, which causes the suspension system to move the vehicle downwards and The stroke limit of the position will be reached. The start of such a movement of the vehicle Suitable means are provided for detecting and the control device is connected to the suspension spring means. Working to increase the force provided, the wheel finally assumes its previous position. It's going to rise a lot. When this former position is reached, the control adjusting the force applied by the spring means so that the spring means balances the new vehicle weight; This ensures that the vehicle always remains at a predetermined suspension height. the vehicle is being driven When the suspension is moved, the suspension moves around the mean position as described above.

When the vehicle steers around a corner, this causes the vehicle to roll, so The controller controls the rolling by adjusting spring means in response to detecting the onset of rolling. Compensate. Similarly, changes in vehicle attitude due to vehicle pitching, i.e. longitudinal acceleration will also be compensated. the car to add other parameters to which the controller responds. Means may be provided for detecting the profile of the road at some distance in front of both.

The control device has a response time, so when the vehicle is traveling at high speed, No change in spring force occurs from transient high-frequency wheel motion caused by the road surface. system Since the control device operates with a long time constant, load changes, gradients, etc.

It only responds to cornering and longitudinal acceleration.

As mentioned above, the spring element according to the first aspect of the invention does not necessarily have to be in an increased buckling condition. It does not provide an absolutely constant force to resist its deformation. In fact The force exerted by the element may vary by up to about 10% from its normal value; The meaning of "approximately constant force" includes such changes. one or more like this When more elements are used in a vehicle suspension system, the suspension geometry becomes more constant. The wheel carrier member is configured such that a near force or zero rate is provided to the wheel carrier member. Ru.

of the movement of the spring element or its respective ends (preferably) at the point of connection with the vehicle structure; The path is such that it provides the required spring rate in the wheel or the spring element or Apply the minimum force necessary to change the position of each connection. sea urchins are selected. Examples of such movement paths are described below.

The invention will now be described by way of example with reference to the accompanying drawings. here, 1 is a schematic diagram of a vehicle suspension according to the invention, and FIG. 2 shows that the spring elements of the suspension are is a schematic diagram showing how it is connected to parts of the rack; FIG. 3 is an S diagram showing the shape of the spring element of the suspension system, and FIG. 4 is a diagram showing the geometry of the suspension system.

The vehicle suspension system shown in FIG. 1 supports a stub shaft equipped with a wheel mounting flange 11. The wheel carrier member 10 includes a wheel carrier member 10 having a wheel carrier member 10. The aperture that extends from the wheel carrier member The system 12 provides a connection with the steering link. Similarly, drive shaft 13 and boot A portion of the boot 14 is shown, which is the torque transmitting connection with the stub shaft. It is coated with a constant speed universal joint that provides.

The wheel carrier member is connected to the upper wishbone and It is connected to each of the lower wishbones 17 and 18. Witshubo The chassis or part of the body of the vehicle not shown in the bushes 19 and 20 is Provides a pivot connection with the chassis structure. Wishbone is a predetermined route Vertical or nearly vertical movement of the wheel carrier member 1o relative to the vehicle structure along Provide movement.

In this case, spring means are provided consisting of four elongated elements; One end engages a part of the wheel carrier member not visible in the drawing and the other end The end portion engages with the abutment member 21 . Abutting member 2 supported by the vehicle structure 1 relative to the vehicle structure by means of a hydraulically actuated piston and cylinder arrangement 22. Its position is adjustable. The abutment member 21 is connected to the vehicle structure when the wheel carrier member is When moved upward relative to the structure, the abutment member and the other end of the spring element engage. arranged in such a way that the distance between the parts of the wheel carrier members that are joined together is reduced. There is. When the position of the abutment member is adjusted by the device 22, the wheel carrier member The leverage between the spring element and the spring element is changed.

The spring element, the top one of which is visible as 23, may be made of spring steel plate or other suitable elastic material. These may be made of materials that are buckled into an arcuate shape, thereby making them By applying force between the wheel carrier member and the abutment member 21, the wheel carrier member resisting upward movement relative to the vehicle structure. The shape of the spring element 23 is so that they act as nearly constant force springs i.e. zero rate springs, i.e. The force increases when the straight distance between their ends is decreased and their bending is increased. It is such that there is no substantial increase. As shown (and described in detail below) ), the spring element has a moon-shaped shape, the sides of which are generally arcuate ( is part of a sine curve).

A spring element such as that indicated at 24 for the top element 23 is connected to the abutment member 21. Each end of each engaging spring element is widened to provide an extension knife pivot. I'm getting lost.

Referring now to FIG. 2, the ends of the spring elements are connected to the abutment member 21 and the wheel carrier. It is shown here how it engages parts such as the ear member 10. sa The dollar members 30 are arranged at intervals! = Two generally V-shaped parts 31.32 and a portion 33 extends between these portions, the portion 33 having spaced apart portions therebetween. A plurality of V-shaped recesses 34 are provided, the recesses 34 being located at the ends of the spring element. and two of the spring elements are shown as 35.36 in this figure. ing. The end of the spring element is provided with a knife pivot shape.

The number of such V-shaped recesses 34 will of course depend on the required number of springs used. It is. The saddle member 3o is fitted onto the support member 37, and this support portion The material 37 was placed at a spacing such that the core coincided with the knife support surface 40.41. It has two upright parts 38,39. These are parts 31 and 32 of the saddle member. 42, thereby causing the saddle member to fit within a small range around axis 42. Pivot movement is possible within the surrounding area. the portion 33 with which the end of the spring element engages; is located below the shaft 42 in the arrangement of the drawings, so the saddle member 3o is biased by the spring element. It will automatically center itself according to the direction of the applied force.

As explained above, the above vehicle suspension system uses a fluid pressure operated piston and a cylinder. The suspension device adjusts the position of the abutment member 21 by means such as the suspension device 22. requires a control system to ensure operation around the average position determined. Figure 1 As shown schematically in Figure 4, the control device designated as 45 is a height or distance measuring device. , thereby allowing the members of the suspension system, such as the upper wishbone 17 provides a signal representing the position of the This signal is processed appropriately to control the valve, and the valve Determining the flow of fluid to or from the device 22 to determine the requirements of the abutment member 21. Establish the desired position. Other vehicle operating parameters to which the control responds are e.g. Directional acceleration, longitudinal or angular acceleration, steering angle, or the road the vehicle is approaching Contains detected features or properties of the road surface.

FIG. 3 shows a schematic representation of one moon-shaped shape of the spring element 23, from which it can be seen that the expanded Ifetuji end portion has been omitted. The shape of the element is defined by the following formula.

R Here, L is the total length of the undeformed element, and WO is the center point between the ends of the element. W is the width of the element at distance X from the center point of the element, R is the maximum width of the element This is the radius of curvature when bent to the maximum deformation state.

For an element of constant thickness, such a shape reduces the response of the element when it is buckled. Provides approximately uniform stress on the force surface.

Spring elements such as the shape above may be made of composite material (fiber reinforced plastic) or other suitable materials. It can be made of any suitable elastic material.

Referring now to FIG. 4, the spring geometry shown in FIG. 1 is diagrammatically illustrated.

A pivot-connected suspension member, such as a wishbone, is shown by line A-B. and the member is pivoted at B about an axis perpendicular to the drawing plane. . At A, a wheel carrier member etc. can be fixed. Spring of the present invention The element is pivotally connected to the suspension member at point C, and the other end of the spring element The appropriate position for the abutment is a semicircle on the line C-B when the suspension member A-B is horizontal. (center of curvature 0). The other end of the spring element is Pivot connection is made at a point D on the semicircle, for example. At this time, the force at A has an approximately constant relationship to the force exerted by the spring element itself, and therefore The leverage will be approximately constant.

When the position of the dot is moved to Dl, for example, the force at A becomes D'' in the ratio of B:DB. , but the force will again be constant regardless of wheel position.

In this way the force at the wheel can be adjusted to an appropriate value by the control device described above. It is.

Adjustment ranges for the dots can be provided, for example from E to El. The point is actually can be moved in a straight line as shown in the figure. That is, this allows It can be well approximated to the theoretical motion path that operates. For example, linear motion is shown in Figure 1. by a hydraulically actuated piston and cylinder arrangement as shown at 22 in or Easily provided by an electric motor driven screw and nut device.

Abutment of a spring element on a semicircle with center of curvature 0 (or on an arc of such a semicircle) As an alternative to the movement of the member, the point of abutment is such that the suspension member is in a horizontal position (or ) at the connection point C of the spring element with the suspension member. It is possible to move on an arc with a center of curvature. This is the adjustment range of the spring contact member. This reduces the amount of force applied by the actuator when changing the contact position. The force exerted on the wheel carrier member is minimal, but since the suspension pivots, There are large variations in the force applied to the

The vehicle suspension system has been described above, and the suspension system and the vehicle suspension system according to the present invention have been described above. It has been found that spring devices are more generally applicable where similar requirements occur. It will cost you money. For example, the invention provides a method for moving parts or assemblies to other plants or equipment. parts or assemblies so as to insulate them from motion or vibration affecting parts of the parts or assemblies. Applicable to plant or equipment for which suspension systems are required for support. Ru. Dynamic changes in the operating parameters of equipment occur in the same way as for vehicles. If not, the connection point of the spring element(s) with one or more of the suspended parts. This would be possible by making the position manually adjustable. Other applications of the invention An example is a rail-based vehicle or a watercraft, in which case some type of suspension location is required.

means for performing the disclosed functions or methods for obtaining the disclosed results; The above-disclosed aspects, claims, and other aspects of the process suitably described in a particular form or terminology. The scope of the claims and the accompanying drawings are intended to illustrate the invention in its various forms. These forms can be used independently or in any combination.

abstract The spring element has a moon-shaped shape with arched sides, which gives the spring element an arcuate shape. When bent into a shape, it resists movement of its ends toward each other to provide almost constant force. This element changes the suspension geometry and Vehicle suspension with devices for modification to change vehicle loading and dynamic conditions available for equipment.

Claims (23)

[Claims] 1. Actuation between two parts that are movable relative to each other to change the distance between them a spring element for connecting said two parts, said element being in an elongated shape and touching said two parts; having end portions designed to be connected, such that said portions are facing each other. When moved in the matching direction, the element is deformed in a direction that gradually increases the buckled shape. , the shape of said element is substantially uniform on its surface when said element is thus deformed. such that it provides an equal stress and that the relative movement between the two parts a spring element between which a substantially constant force is exerted by said element on said part; . 2. Extensional struts with centerlines that lie in a single plane when the spring element is buckled including lip material, the amount of material within the width dimension of the strip being at or near its ends; varies from a minimum value at adjacent locations to a maximum value midway between its ends Spring element according to claim 1. 3. The change in the amount of material in the width dimension of the strip corresponds to the change in the width of the moon-shaped element. Spring elements according to claim 2, which are the same. 4. Spring element according to claim 3, which is moon-shaped. 5. The spring element according to claim 3 or 4, wherein the moon-shaped shape is defined by the following formula: W=WO((cos(X/R)-cos(L/2R))/(1-cos(L/2 R))) (where L is the total length of the undeformed element and WO is the center between the ends of the element. The maximum width of the element at the point , W is the width of the element at distance X from the center point of the element, R is the radius of curvature when the element is bent to its maximum deformation). 6. A spring element according to any of the preceding claims consisting of metal. 7. Spring element according to any one of claims 1 to 5, consisting of a composite material. 8. such that the ends of the spring element are pivotally connected to two relatively movable parts. A spring element according to any of the preceding claims designed. 9. 9. Both ends of the spring element have contact surfaces for contacting the movable part. spring element. 10. A suspension device for suspending a first member relative to a second member, , means for constraining the first member to a desired path of relative movement relative to the second member; Spring means arranged between two parts attached to said member, one part being The distance between said two parts changes when moving relative to the other part, and the front The spring means maintains a substantially uniform force between the parts when the parts are in relative motion with respect to each other. at least one spring element connected to said portion to provide a constant force. and the at least one spring element and at least one of said members. means for changing the force exerted between members by spring means by changing the geometrical relationship; and a suspension system including. 11. The or each spring element is an element according to any one of claims 1 to 9. and the spring element is configured to move the portions together such that the spring element is deformed to the buckled configuration. in such a way as to apply a force that causes the parts to move apart, and in a direction in which said parts face each other. 11. Connected to said portion in such a way that buckling increases when moved. suspension system. 12. said change in geometry of one of said portions of at least one spring element; 12. The suspension device according to claim 10 or 11, including a change in the connection position between the two. 13. a suspension system for a vehicle, the member comprising a wheel carrier member and a spring; Claims 10 to 12, comprising a part of a supporting vehicle structure. suspension system. 14. In response to at least the measurement of the relative position between the two members, said geometric shape Claim 10 further comprising control means operative to produce a change in the relationship. 14. The suspension device according to any one of 13. 15. The wheel carrier member is moved along a generally perpendicular demand path relative to the vehicle structure. means for restraining the road and the wheel carrier moving upwards relative to the vehicle structure; placed between the two parts such that the distance between the two parts decreases when 10. A vehicle suspension system comprising: a spring means, wherein the spring means is the spring means according to any one of claims 1 to 9. at least one spring element according to any one of the preceding claims, wherein both ends of the spring element Applying a force that forces the parts apart from each other so that they are deformed into the buckled shape. so that the buckling increases when said parts move towards each other. the at least one elongated element is pivotally connected so as to At least one connection location of the portion is mounted on the wheel carrier member by spring means. A vehicle suspension system that is adjustable to vary the supported forces. 16. said at least one elongation in response to at least one operational parameter; a control hand for adjusting the connection position of the at least one portion of the member; 16. The vehicle suspension system of claim 15, further comprising a step. 17. said control means causing the suspension to operate around a desired average position; 17. The vehicle suspension system of claim 16, wherein the vehicle suspension system is operative. 18. When the wheel carrier member moves relative to the vehicle structure, the the force applied to the wheel carrier member is substantially constant at each connection position; such that the contact with the at least one portion of the at least one elongated element is 18. The connecting position is movable along a path. vehicle suspension system. 19. The small The connection position with the at least one portion of at least one elongate element is one The vehicle suspension system according to any one of claims 15 to 17, which is movable along a path. . 20. Both ends of the at least one spring element are supported by at least one spring element. the connected parts so that they self-center in response to the direction of the applied force. 12. The suspension system of claim 11, wherein A vehicle suspension system according to any one of claims 15 to 19. 21. A spring element substantially as shown in the accompanying drawings. 22. A suspension system substantially as shown in the accompanying drawings. 23. Novel aspects or aspects described herein and/or in the accompanying drawings A new combination of