Suspension device

Abstract

The invention relates to a suspension device, in particular for a vehicle seat, comprising an upper suspension part and a lower suspension part, which can be connected to one another by a first swivelling connector and a second swivelling connector, wherein a first spring unit can be connected in a first end region on the one hand by means of an adjusting device to the first swivelling connector and can be connected in a second end region on the other hand to the lower suspension part, wherein by means of the adjusting device the position of the first spring unit can be adjusted in order to adjust the spring force and the spring rate of the suspension device.

Claims

1. A suspension device, for a vehicle seat, comprising: an upper suspension part and a lower suspension part, wherein the upper suspension part and the lower suspension part can be connected to one another by a first swivelling connector and a second swivelling connector, wherein a first spring unit can be connected in a first end region by an adjusting device to the first swivelling connector and can be connected in a second end region to the lower suspension part, wherein by means of the adjusting device, a position of the first spring unit can be adjusted, in order to adjust a spring force and a spring rate of the suspension device, wherein the adjusting device comprises an adjusting element, wherein a first lever element is arranged pivotably on the adjusting element by means of a second axis of rotation, wherein a second lever element is arranged pivotably on the first lever element by means of a third axis of rotation and the second lever element is connected pivotably to the first swivelling connector by means of a fourth axis of rotation, wherein the adjusting device comprises a rotary lever which is stationary relative to the first swiveling connector, which rotary lever is rotatably mounted about a first axis of rotation, which is stationary relative to the first swiveling connector, and wherein the adjusting element can be displaced along a displacement axis.

2. The suspension device according to claim 1, wherein a position of the first end region of the first spring unit can be adjusted by means of the adjusting device, and wherein a position of the second end region is constant.

3. The suspension device according to claim 1, wherein the suspension device comprises at least one damper, wherein a first end region of the damper can be connected to the adjusting device.

4. The suspension device according to claim 1, wherein the second swivelling connector is designed to be longer than the first swivelling connector.

5. The suspension device according to claim 1, wherein the displacement axis corresponds to the first axis of rotation.

6. The suspension device according to claim 1, wherein the first spring unit is formed by a spring, wherein preferably the spring is a tension spring.

7. The suspension device according to claim 1, wherein the first spring unit is at least connected operatively to the second lever element.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) Further aims, advantages and benefits of the present invention can be taken from the following description in connection with the drawings, in which:

(2) FIG. 1A shows the suspension device with a true parallelogram and a vehicle seat;

(3) FIG. 1B shows the suspension device with a false parallelogram and a vehicle seat;

(4) FIG. 2A shows the suspension device according to FIG. 1A;

(5) FIG. 2B shows the suspension device according to FIG. 1B;

(6) FIG. 3A is a perspective view of the suspension device according to one embodiment;

(7) FIG. 3B is a perspective view of the suspension device with an adjusting device according to one embodiment;

(8) FIG. 3C is a side view of the suspension device according to FIGS. 3A and 3B;

(9) FIG. 3D shows an adjusting device according to a further preferred embodiment;

(10) FIG. 4A is a side view of the suspension device with an adjusting device according to FIG. 3A;

(11) FIG. 4B is a plan view of the suspension device according to FIG. 4A;

(12) FIG. 5A is a side view of the suspension device with an adjusting device according to FIG. 3D;

(13) FIG. 5B is a plan view of the suspension device according to FIG. 5A;

(14) FIGS. 6A, 6B shows the suspension device with a spring in different adjusting positions;

(15) FIGS. 7A, 7B shows the characteristic curve of the suspension device for a light and a heavy driver;

(16) FIGS. 8A, 8B shows the characteristic curve for the suspension device according to one embodiment with a false parallelogram for a light and heavy driver who is sitting in the front;

(17) FIG. 8C shows the characteristic curve for the suspension device according to FIGS. 8A, 8B for a heavy driver who is sitting in the back.

DETAILED DESCRIPTION

(18) The suspension devices 1 shown in FIGS. 1A and 1B comprise an upper suspension part 3, a lower suspension part 4, a first swivelling connector 5 and a second swivelling connector 6. The upper suspension part 3 is connected in a front region 3 by means of a third pivot axis 13 to the first swivelling connector 5 and in a rear region 3 by means of a fourth pivot axis 14 to the second swivelling connector 6. The lower suspension part 4 is thereby connected in a front region 4 by means of a first pivot axis 11 to the first swivelling connector 5 and is connected in a rear region 4 by means of a second pivot axis 12 to the second swivelling connector 6.

(19) In this case FIG. 1A shows the suspension device 1 with a true parallelogram and FIG. 1B shows the suspension device 1 with a false parallelogram.

(20) The difference between the true and the false parallelogram is illustrated more clearly in FIGS. 2A and 2B, wherein FIG. 2A shows the suspension device 1 with the true parallelogram and FIG. 2B shows the suspension device 1 with the false parallelogram, wherein in FIG. 2B the second swivelling connector 6 is designed to be longer than the first swivelling connector 5, wherein in particular the length between the second 12 and fourth pivot axis 14 is longer than the length between the first 11 and third pivot axis 13. In particular the corner points of both the true and false parallelograms are formed by the first, second, third and fourth pivot axis.

(21) As can clearly be seen from a comparison of FIGS. 2A and 2B the upper suspension part 3 at least in the shown lower position is no longer parallel to the lower suspension part 4. Furthermore, it can be seen that the overall height h of the suspension device 1 is only slightly increased to the height h. The heights h and h are measured as the distance between a lower side 18 of the lower suspension part 4 and an upper side 19 of the upper suspension part 3.

(22) According to FIG. 2B however, as described above, the upper side 19 of the upper suspension part 3 in the lower position is no longer parallel to the lower side 18 of the lower suspension part 4, so that the height is measured between the lower side 18 and the highest point of the upper side 19, as viewed in the vertical direction H of the vehicle seat.

(23) However, this slight change in the true parallelogram towards the false parallelogram has a significant effect on the suspension device 1.

(24) By lengthening the second swivelling connector 6, in particular by lengthening the distance between the second 12 and fourth pivot axis 14, the upper suspension part 3 is adjusted in its position or location so that the upper suspension part 3, in particular the upper side 19 of the upper suspension part 3, is no longer parallel to the lower suspension part 4, in particular the lower side 18 of the lower suspension part 4. In this way the direction of force 16 is also changed in position, as the direction of force 16 is defined by the third 13 and the fourth pivot axis 14. As shown from a comparison of FIGS. 2A and 2B, due to the change in position of the direction of force 16, the force lever 17 also changes, which is arranged to be perpendicular to the direction of force 16 and is running through the second pivot axis 12. As said force lever 17 is lengthened by the slight lengthening of the second swivelling connector 6, the joint forces, in particular in the region of the lower suspension part 4, and the frictional forces are reduced. Furthermore, as the upper suspension part 3 is no longer parallel to the lower suspension part 4, a spring characteristic curve of the suspension device 1 and also a spring rate and an extension force are dependent on the actual weight position relative to the upper suspension part.

(25) It is therefore possible to configure the spring characteristic curve of the suspension device 1 to be very progressive. A heavy vehicle driver is generally also taller in body height so that a heavy vehicle driver will sit further back on the vehicle seat 2. The spring rate of the suspension device 1 is then greater with a heavier driver than the spring rate with a lighter and smaller driver. In this way also it is possible to perform an automatic adjustment of the spring rate of the suspension device 1 to the weight of the driver.

(26) In the following the operation of the adjusting device 9 is described in more detail.

(27) FIG. 3A is a perspective view of the structure of the suspension device 1. The lower suspension part 4 comprises a linear displacement means 20 so that the suspension device 1 can be displaced linearly in longitudinal direction L.

(28) The structure of the suspension device 1 with a true parallelogram corresponds to the structure of a false parallelogram, the difference only being the second swivelling connector 6. The other structural components are designed to be essentially identical. The rotary lever 15 of the adjusting device can also be seen as well as a suspending device, by means of which springs of the suspension device 1 and dampers (not shown here) can be connected to the lower suspension part.

(29) The lower suspension part 4 comprises two longitudinal elements 23, 24, which each extend in longitudinal direction L and two transverse elements 25, 26, which extend in width direction B.

(30) The suspending device 21, which is arranged here in the rear region 4 of the lower suspension part 4, comprises a first suspending element 27, which extends in width direction B and is designed to be tubular, wherein other configurations are also possible, for example square or hexagonal shapes. However, a tubular configuration is preferred, as eyelets of springs (not shown here) can be held particularly effectively. Furthermore, the suspending device 21 comprises at least one first damper suspension element 28, by means of which one end of a damper 22 can be connected to the lower suspension part 4.

(31) FIG. 3B shows a first embodiment of the adjusting device 9. As shown the adjusting device 9 comprises a rotary lever 15 which is rotatable about a first axis of rotation 29, wherein preferably both the rotary lever and the first axis of rotation are arranged to be stationary relative to the first swivelling connector 5. In this case stationary means that the position of the component is constant, but rotations are permitted. The rotary movement of the axis 29 is transmitted by means of two cone gear wheels (not shown here) to the axis 30. Of course other configurations for transmitting the rotary movement are possible.

(32) Furthermore, the adjusting device 9 comprises an adjusting element 33, which can be connected to the first axis of rotation and can be displaced with an adjustment along a displacement axis 35. According to the embodiment shown, the displacement axis 35 corresponds to the axis of a threaded rod 34 and is arranged to be perpendicular to the first axis of rotation 29.

(33) Furthermore, a first lever element 36 can be arranged pivotably on the adjusting element by means of a second axis of rotation 30, wherein on said first lever element 36 a second lever element is arranged pivotably by means of third axis of rotation 31 and the second lever element 37 can be connected pivotably by means of a fourth axis of rotation 32 to the first swivelling connector 5.

(34) Here a second suspending element 38 is arranged on the second lever element 37 for suspending an eyelet of a spring. Preferably, also a second damper suspending element 39 is secured to the second lever element 37.

(35) FIG. 3C shows the embodiment of a suspension device 1 shown in FIG. 3A and 3B in a side view with a damper 22 and a spring 40.

(36) In FIG. 3D a further embodiment of the adjusting device 9 is shown. However, in this case the displacement axis 35 is not perpendicular to the first axis of rotation 29, but corresponds to the first axis of rotation 29. Furthermore, the rotary movement of the axis of rotation 29 is not transmitted by gear transmission to the axis of rotation 30 but is transmitted by means of a gate-type gear.

(37) It is also possible that, independently of the design of the adjusting device 9, with at least two springs 40, as shown in FIG. 3D, only one spring 40 is connected to the second suspending element 38 and the other spring 40 is connected directly to the first swivelling connector 5. In this way the suspension device 1 has a certain minimum spring output, defined by the spring 40, which is not connected to the adjusting device 9.

(38) FIGS. 4A and 4B show once again the embodiment according to FIG. 3B and FIGS. 5A and 5B show the embodiment according to FIG. 3D, in both side view and in plan view.

(39) As shown in particular in FIG. 4A and 5A, the first swivelling connector 5 comprises a recess 42, which corresponds essentially to the transverse element 25, so that the first swivelling connector can be pivoted downwards as far as possible in vertical direction H. Furthermore, by means of said recess 42 the suspension device 1 can be made to have smaller dimensions overall, otherwise the first swivelling connector 5 cannot be lowered so far. However, this is possible by means of the recess 42, as shown in FIG. 4A and 5A. The embodiment of the adjusting device 9 of FIGS. 3D, 5A and 5B compared to the embodiment of the adjusting device 9 according to FIGS. 3B, 4A and 4B has reduced friction of the components so that the adjusting device 9 can be activated with less force.

(40) In FIGS. 6A and 6B the kinematics of the suspension device 1 is shown schematically, wherein the suspension device 1 is formed by a true parallelogram. FIG. 6A shows the situation for a light driver, FIG. 6B the situation for a heavy driver.

(41) As shown clearly from a comparison of FIGS. 6A and 6B, by activating the adjusting device 9 a lever length 43 is changed. For a light driver said lever 43 is shorter than for a heavy driver, so that with a heavy driver force or energy can be absorbed by the spring 40. The resulting lever length 43 is therefore shorter.

(42) The characteristic curve of the suspension for a light driver is shown in FIG. 7A and for a heavy driver in FIG. 7B. The values are given by way of example, but other values may also be used.

(43) The following drawings relate to an embodiment with a false parallelogram and two springs 40, wherein a first spring 40 is connected to the adjusting device 9 and can be adjusted in position accordingly, wherein the second spring 40 is connected directly to the first swivelling connector 5 and cannot be adjusted. The characteristic curves shown relate to the whole suspension, i.e. to both springs 40.

(44) The characteristic curves shown in FIGS. 8A and 8B show a comparison between the suspension device 1 with a true parallelogram and a false parallelogram for both a light driver and a heavy driver, who has an effect on the suspension device 1 as viewed in the longitudinal direction at the front of the suspension device 1. The characteristic curve for the true parallelogram is on the left, the characteristic curve for the false parallelogram is on the right.

(45) As can be seen from a comparison, the spring rate of the true parallelogram is significantly different from the false parallelogram and relates more to the driving comfort of the respective user.

(46) However, as a heavy driver is generally taller than a light driver, the heavy driver has more of an effect on the rear of the suspension device 1. This is illustrated in FIG. 8C. As can be seen, the characteristic curve of the suspension can be configured to be very progressive. In this case the characteristic curve is more or less linear up to 1417 N, and after this it changes significantly. In addition, due to this very progressive configuration, the weight of the suspension device 1 can be reduced, as it is possible to avoid having end-stop buffers.

(47) All of the features disclosed in the application are claimed as being essential to the invention, insofar as they are novel over the prior art either individually or in combination.

LIST OF REFERENCE NUMERALS

(48) 1 suspension device

(49) 2 vehicle seat

(50) 3 upper suspension part

(51) 3 front region of the upper suspension part

(52) 3 rear region of the upper suspension part

(53) 4 lower suspension part

(54) 4 front region of the lower suspension part

(55) 4 rear region of the lower suspension part

(56) 5 first swivelling connector

(57) 6 second swivelling connector

(58) 7 first spring unit

(59) 8 first end region of the first spring unit

(60) 9 adjusting device

(61) 10 second end region of the first spring unit

(62) 11 first pivot axis

(63) 12 second pivot axis

(64) 13 third pivot axis

(65) 14 fourth pivot axis

(66) 15 rotary lever

(67) 16 force direction

(68) 17 force lever

(69) 18 lower side lower suspension part

(70) 19 upper side upper suspension part

(71) 20 linear displacement means

(72) 21 suspending device

(73) 22 damper

(74) 23 longitudinal element

(75) 24 longitudinal element

(76) 25 transverse element

(77) 26 transverse element

(78) 27 first suspending element

(79) 28 first damper suspending element

(80) 29 first axis of rotation

(81) 30 second axis of rotation

(82) 31 third axis of rotation

(83) 32 fourth axis of rotation

(84) 33 adjusting element

(85) 34 threaded rod

(86) 35 displacement axis

(87) 36 first lever element

(88) 37 second lever element

(89) 38 second suspending element

(90) 39 second damper suspending element

(91) 40 spring

(92) 41 eyelet

(93) 42 recess

(94) 43 lever length

(95) B width direction

(96) L longitudinal direction

(97) H vertical direction