SE1200283A1 - Chair with rocking resistance - Google Patents

Abstract

The invention relates to an adjustment device for chairs, for adjusting a swaying resistance for a backseat part of a chair. The adjustment device comprises a chair base (10), a backrest part (20) pivotally arranged to the chair base (10) around a pivot shaft (40) and at least one spring element (31, 32) having a first end (31 a, 32a) arranged to the chair base (10) and a second end arranged to the backrest part (20), whereby the spring element (31, 32) has a spring force having a force direction parallel to the direction of the spring element from its first end to its second end, and that the spring element is arranged such that when the backrest part is loaded, the spring element will be loaded. The adjustment device further has a setting mechanism (50, 51) for setting the force of the spring element, whereby the setting mechanism (50, 51) is arranged to move the spring element (31, 32) such that the force direction of the spring element is changed and whereby the setting mechanism (50, 51) is arranged to move the first end (31 a, 32a) of the spring element or the second end (31 b, 32b) of the spring element substantially perpendicular to the force direction of the spring element. The invention further relates to a chair provided with such an adjustment device.

Description

TECHNICAL FIELD The present invention relates to a device for giving a resistance in the backrest and / or the seat to a chair when rocking back of the chair.

BACKGROUND A chair such as a work chair has a chair base and a backrest part which are rotatably connected to each other via a pivot axis so that when the user presses his back against the backrest the backrest part will be rotated around the pivot axis so that the backrest is tilted backwards. In addition, the chair has a resistance, for example a so-called rocking resistance, which hails against this movement of the backrest baked. The rocking resistance can be realized with the aid of one or more springs which are connected to the chair base with one of its spirits and to the back of the chair with its other spirits. When the chair's backrest is loaded backwards, the springs will be stretched out so that the spring force will resist the movement of the backrest backwards and / or the seat downwards.

The load on the delta rocking resistor can be adjusted manually by the user by, for example, turning a raft, so that the user can get the resistance that suits that particular user. The steering wheel can change the tension in the spring, or rather the position of the spring so that the spring, when you turn the steering wheel in the direction of increased load, is stacked more when you bend the back of the chair backwards. Today's solutions for the second load on the swing resistor require the user to screw several variables on the steering wheel in order for the second load between its outer layers, and / or that the user must take in a large force to turn the steering wheel in order for the second load.

In order to make it easier for a user to place the second load on a rocking resistor, there is a need to be able to easily change the load on the rocking resistor.

SUMMARY OF THE INVENTION 2 An object of the present invention is thus that a simple and flexible salt can withstand the load of a rocking resistor in a chair with rocking resistance.

This object is achieved according to a first aspect of the invention with an adjusting device for chairs, intended to adjust the rocking resistance of a backrest part of a chair. The adjusting device comprises a seat base, a backrest part rotatably arranged to the seat base about a pivot axis and at least one feeder element with a first spirit arranged to the chair base and with a second end arranged to the backrest part, the spring element having a spring force parallel to the direction of force between its first spirit and its second spirit, and the spring element is arranged so that when the backrest part is loaded so that when the backrest part is rotated in relation to the chair base, the spring element will be loaded. The adjusting device further has an installation mechanism for installing the spring of the spring element which is arranged to move the spring element so that the force direction of the spring element is different and the installation mechanism is arranged to move the first or second spirit of the spring element substantially perpendicular to the direction of spring element.

As a result, a user can, without even having to do so, apply a particularly large force to a single salt second load on the rocking resistor.

Due to the fact that the second position of the first element of the spring element moves so that the first end of the spring element is moved substantially perpendicular to the direction of extension of the spring element, the force which the spring element itself exerts towards the seven movements will be very small, making it easier for a user to load. Thus, the user can also use the second force in the swing resistance with a relatively large gear ratio, but the user also has to take in too much force. This makes it possible, for example, to design the installation mechanism so that if the user with one revolution or even less than one revolution moves on a raft, the second installation on the swing resistance can be from its smallest to its highest resistance.

By a spring element is meant an element which provides a resilient force in the direction of the element, such as a mechanical traction die, a gas spring, etc. By a chair base is meant the 3 part of which the chair itself is made, i.e. the part of the chair which the chair stands on. on a floor, does not perform any twisting motion or the like relative to the floor. The base of the chair can also be called the central nay of the chair, or the yoke of the chair. The seat of the chair can be fisted on the base of the chair. By loading the backrest part is meant that the backrest is pressed backwards so that the backrest part is rotated in relation to the chair base. By the backrest part being loaded so that the spring element is loaded is meant that when the backrest part is pressed backwards / downwards, the spring element will all be pulled out.

According to an embodiment, the adjusting device further comprises a spring frame via which the first spirit of the spring element is arranged to the chair base, which spring frame has a first part arranged to the first spirit of the spring element and a second part rotatably arranged to the chair base. The second part of the spring frame is further rotatably arranged to the chair base in the area where the second part of the spring element is arranged to the backrest part when the backrest part is unloaded.

By using a spring frame arranged for the chair base with its second part, and arranging the first part of the spring frame for the same attachment as the first Linde of the spring element, the spring frame will control the movement of the first element of the spring element for changing the spring element. By all means place the second part of the spring frame in the area ddr, ie. adjacent, the second spirit of the spring element is arranged to the backrest part, when the backrest is unloaded, the spring element will move substantially perpendicular to the direction of extension of the spring element. Thus, it will all be easy for a user to without flagon greater force other rocking resistance. In addition, the spring frame allows the feeder, if the back of the chair is unloaded, to be in a prestressed condition.

According to a second aspect of the invention, there is provided a chair comprising a seat, a backrest, and an adjusting device according to the first aspect of the invention, wherein the seat is arranged to be fastened to the chair base and the backrest is arranged to be fastened to the backrest part.

BRIEF DESCRIPTION OF THE DRAWINGS 4 The invention will now be described, by way of example, with reference to the accompanying drawings, in which: Fig. 1 is a side view of a work chair comprising an adjusting device according to the invention; Fig. 2 is a perspective view of a part of a chair with adjusting device according to an embodiment; Fig. 3 is a schematic illustration of different spring layers K, L, M and N; Fig. 4 is a side view in section of an embodiment of the adjusting device, with the backrest part unloaded and with one end of the spring in a first layer; Fig. 5 is a side view in section of an embodiment of the adjusting device, with the backrest part loaded and with one end of the spring in the first layer; Fig. 6 is a side view in section of an embodiment of the adjusting device, with the backrest part unloaded and with one end of the spring in a second layer; Fig. 7 is a side view in section of an embodiment of the adjusting device, with the backrest part loaded and with one end of the feeder in the other end; and Fig. 8 is a perspective view in section of an embodiment of the adjusting device, with one end of the spring in the other layer.

DESCRIPTION OF EMBODIMENTS Figure 1 shows a work chair having a seat 1, a backrest 2 and a foot (not shown). The work chair also has an adjusting device, with a chair base 10 on which the seat 1 is arranged, and a backrest part 20 on which the backrest 2 is arranged. To arrange the foot of the chair to the chair base, the chair base has a relatively centrally located opening 15 (see Fig. 2) intended to receive the foot of the chair. The backrest portion has a horizontal portion 20a which is located substantially horizontally when the backrest is unloaded, and a vertical portion 20b which is located substantially vertically when the backrest is unloaded. The vertical part is intended to receive the backrest itself. The seat base 10 and the backrest part 20 are arranged to each other via a pivot shaft 40, so that when the backrest is loaded backwards, the backrest part 20 is rotated around the pivot shaft 40 so that the backrest part 20 moves downwards and backwards in relation to the seat base 10. This is also illustrated. 4 and figure 5, ddr figure 4 shows the adjusting device when the backrest is unloaded, and figure 5 shows the adjusting device when the backrest is printed baked.

The work chair also has two parallel-arranged tension springs 31 and 32, respectively, intended to function as a rocking resistor, that is to say to prevent this movement of the backrest being baked. The tension springs are arranged on each side of the opening 15 intended to receive the foot of the chair. The tension springs each have a first end 31a, 32a, which first spirits are connected to the seat base 10 via a common spring shaft 13, which in turn is rotatably connected to the seat base via a spring frame 14 one end of which is attached to the seat base 10. The spring shaft 13 has an extension which is substantially perpendicular to the tension springs. The tension springs each have a second end 31b, 32b, which other spirits are connected to the backrest part 20 via a mounting shaft 23. The mounting shaft 23 has an extension which is substantially perpendicular to the tension springs and it is mounted in the backrest part 20. This mounting shaft 23 may be broken, i.e. the mounting shaft of the tension springs may have a common mathematical axis but different physical axes. The rocking resistor works as follows: The backrest is pressed backwards, the backrest part is rotated around the axis of rotation 40, whereby the mounting shaft 23 moves away from the feeder shaft 13 and the tension springs 31, 32 are extended. When the tension springs are stacked when the backrest is pushed backwards, the spring will again give a resistance to the backrest being pushed backwards. Figure 4 shows one of the tension springs 31 when the backrest is in an unloaded condition. Figure 5 shows the same tension spring 31 when the backrest is pressed back. Figure 5 shows how the mounting shaft 23 for the feeder 31 has been moved neatly and baked when the backrest has been moved backwards.

The resistance that the traction guides provide depends on how much these are pulled out in relation to how much the backrest is pushed back. Since the traction force in a traction spring is directed in the same direction as the traction feather itself between these two spirits, the direction of the spring, the viii saga direction of the feather in relation to how the movement between chair base and backrest part takes place, will determine the rocking resistance of the spring. In other words, where the first and second spirits of the traction fiad are located, respectively, decides the rocking resistance. This is shown schematically in Figure 3. In a first layer KM, the first end 31a of the tension spring 31 is in position K, which meant a low load, and the second Linde 31b of the tension spring, in position M, which meant a resting position, i.e. the backrest is in an unloaded condition. When the backrest is loaded, the second Linde 31b of the tension spring will move to position N, which meant a maximum extended position for the spring, so that the spring ends up in a second position KN where the spring is more extended than in the first layer. The first and second teams are illustrated with dashed lines.

By moving the first end of the spring 31a frail layer K to layer L, the spring ends up in a third layer LM when the backrest is unloaded. When the backrest is loaded, the traction spring's second Linde 3 lb will move to position N so that the spring ends up in a fourth position LN where the spring is more extended than in the third layer. The third and fourth teams are illustrated with solid lines. As can be seen in the figure, illustrated by lines 102 and 104 showing the length of the load in the unloaded layer projected on the length of the fiad in the loaded layer, the spring will be stretched more as it moves from the third layer LM to the fourth layer LN as it moves from the first team KM to the second team KN. Thus a higher rocking resistance is achieved for the spring when the first Linde of the spring is moved from position K to 'age L. In general it can be said that the more parallel the direction of extension of the spring is with the distance that the spring moves when the backrest is loaded, ie the distance from M to N in the figure, the greater the swing resistance.

For this purpose, the chair has an installation mechanism for second load in the rocking resistor, comprising an actuator 50 coupled to the pivot shaft 40, (around which the backrest part 20 moves in relation to the seat base 10) and an eccentric 51 arranged on the pivot shaft which in turn lies against the spring shaft 13 of the tension springs By rotating the actuator 50 so that the rotary shaft 40 is rotated, the eccentric 51 will secondly move and move the spring shaft 13 of the drawstrings. If a user turns the actuator in a direction, for example clockwise (illustrated by "+" in Figure 2) , the eccentric 51 will move the spring shaft 13 upwards, which is why the layer for the first spirits 31a, 32a of the traction spring 7 will change so that the rocking resistance becomes stone. Figure 6 shows the adjusting device installed with this stone rocking resistor. The tension spring frames are now arranged in such a way that they have a direction which Or they are pulled out more. The backrest is loaded on what is the case when the tension spring is installed as in Figure 4. Figure 7 shows a tension spring with installation as in Figure 6 fixed to the backrest. is printed baked. Which can be distinguished if, compared with Figure and Figure 7, the tension springs are more elongated at the rear-pushed backrest when the spring is in a slightly higher load (Fig. 7) than when the spring is in the team according to the lower load (Fig. 5). By turning the actuator in the opposite direction, for example counterclockwise (illustrated by "-" in Figure 1), the spring shaft 13 will be moved downwards again in the direction of a height as in Figure 5. In this embodiment the eccentric is located on the rotary shaft 40. It is also possible to refuel that the eccentric 51 and the actuator 50 are mounted on a separate actuator shaft, i.e. separately from the rotary shaft 40. Other variants of actuators may also be envisaged which may cause the first spirits of the tension fiddles to be displaced. In an alternative embodiment, the installation mechanism may be adapted to move the other spirits of the tension springs, i.e. the spirits were born to the backrest part, instead of the first spirits of the traction feathers.

However, the fact that the other direction of the tension springs in order to thereby move the second oscillation resistance by moving the bed for the first (or other) spirits of the tension cadres may mean that a user has to screw on the control member with a certain force. In order to facilitate this movement, according to the invention the installation mechanism is arranged so that it moves the first teeth of the tension springs substantially perpendicular to the direction of extension of the tension springs between their first spirits 31a, 32a and their second spirits 31b, 32b. Because the first spirits of the tension springs are moved approximately perpendicular to the direction of extension of the tension springs, the tension springs will have approximately the same extent before as after the movement. That is to say, no or very little force from the tension springs must be overcome to move the ldge of its first spirits.

According to the invention, the chair carried a so-called spring frame 14 attached to the chair base 10 in order to maintain a substantially perpendicular movement of the first springs 31a, 32a of the tension springs when adjusting the rocking resistance. The spring frame 14 has a first end 14a which is coupled to the spring shaft 13, and a second end 14b which is rotatably attached to the seat base 10 via a spring frame shaft 14c. This meant that the spring shaft 13 is connected to the seat base 8 via the spring frame 14. In other words, the first spirits 31a, 32a of the draw springs are connected to the seat base 10 via the foot shaft 13 and further via the spring frame 14 to the foot frame shaft 14c which is rotatably mounted to the chair base 10.

When the actuator 50 is rotated so that the eccentric 51 moves the spring shaft 13 A. so that the traction feathers 31, 32 of the first breaths 31a, 32a are slightly changed, the length of the first spirit 14a of the feather frame will change. Thus, the spring frame will pivot about the spring frame axis 14c. Since the feeder frame is a fixed construction, the feeder frame will control how the first spirits 31a, 32a of the springs are moved. Because the spring frame shaft 14c is located in approximately the same region as the mounting shaft 23, the tension springs will only be stretched very little when the first spirits of the tension springs are different, so that the user will have little load on the tension springs This means that the traction springs will move without being stretched, or will only be stretched very slightly when the first spirits of the traction springs are moved in relation to the other spirits of the traction springs. Since the spring frame shaft 14c is located in approximately the same region as the tensioning shaft 23 of the tension springs in the backrest part may mean that the spring frame shaft 14c has an adjacent mathematical axis as the tensioning shaft 23 of the tension springs. for a user who is going to change the swing resistance with the help of the actuator. In an advantageous embodiment, the tether frame shaft 14c is concentric with the spring mounting shaft 23. In some cases, when changing the position of the tether feeder shaft 13, a user would not have any resistance from the springs, so the rocking resistance can be easily changed. Since the drawbar springs are fixed in a spring frame, they can have a basic voltage, ie. they can in sift rest mode be! to treat. Thus, no gap arises when the load is to be increased from the resting day.

The solution above has been described with reference to specific embodiments. However, the description should not be construed as limiting the scope of the invention but should be seen as intended to illustrate the idea of the invention. For example, the rocking resistance above is realized with tension springs. However, within the scope of the invention, other types of spring elements (with resistance in their longitudinal direction) can be imagined, such as gas springs, etc. The rocking resistance is also realized with the aid of two spring elements. However, it is possible to use one spring element or more than two spring elements. The installation mechanism for installing the force of the spring element is challenged in the figures as a control member connected to an eccentric. However, one can think of many other variants of installation mechanism. For example, the eccentric may be a screw or gas spring whose longitudinal extent is controlled by a control member.

Claims (10)

PATENT REQUIREMENTS Adjusting device for chairs, intended to adjust resistance to the backrest part of a chair, the adjusting device comprising: a chair base (10); a backrest member (20) rotatably mounted to the seat base (10) about a pivot axis (40); at least one spring element (31, 32) with a first side (31a, 32a) arranged to the seat base (10) and with a second spirit (31b, 32b) arranged to the backrest part (20), the spring element (31, 32) having a spring force with a direction of force parallel to the direction of the spring element between its first spirit and its second spirit, and that the spring element is arranged so that when the backrest part is loaded so that the backrest part is rotated in relation to the seat base, the spring element will be loaded; an installation mechanism (50, 51) for installing the force of the spring element, characterized in that the installation mechanism (50, 51) is arranged to move the spring element (31, 32) so that the direction of force of the spring element changes and wherein the installation mechanism (50, 51) is arranged to move the first end of the spring element (31a, 32a) substantially perpendicular to the direction of force of the spring element. Adjusting device according to claim 1, wherein the first end (31a, 32a) of the spring element is arranged to the seat base (10) via a spring shaft (13), and the second end (31b, 32b) of the spring element is arranged to the backrest part via a fastening shaft (23). Adjusting device according to claim 2, wherein the spring shaft (13) is rotatably attached to the seat base (10) via a spring frame shaft (14c) so that the spring shaft can be moved parallel to its own extent, the spring frame shaft (14c) being arranged to the seat base (10) in the area ddr. the mounting shaft (23) is arranged to the backrest part (20), when the backrest part is unloaded. Adjusting device according to any one of claims 1-3, wherein the adjusting device further comprises a spring frame (14) via which the first dricle (31a, 32a) of the spring element is arranged to the chair base, which spring frame (14) has a first part (14a) arranged to the first end (31a, 32a) of the spring element 11 and a second part (14b) rotatably arranged to the seat base (10). Adjusting device according to claim 4, wherein the second part (14b) of the spring frame is rotatably arranged to the chair base (10) in the area where the second part (31b, 32b) of the spring element is arranged to the backrest part and the backrest part (20) is unloaded. Adjusting device according to claim 5, wherein the second part (14b) of the spring frame is rotatably arranged to the chair base (10) via a spring frame shaft (14c) and the second end (31b, 32b) of the spring element is arranged to the backrest part via a fastening shaft (23). Adjusting device according to any one of claims 3 or 6, wherein the spring frame shaft (14c) and the mounting shaft (23) are concentric when the backrest part is unloaded. Adjusting device according to any one of claims 3 or 6-7, wherein the spring frame shaft (14c) and the mounting shaft (23) are substantially parallel. Adjusting device according to any one of claims 3 or 6-8, wherein the spring frame shaft (14c) and the spring shaft (13) are substantially parallel. A chair comprising a seat (1), a backrest (2), and an adjusting device (4) according to any one of the preceding claims, wherein the seat (1) is arranged to be fixed to the chair base (10) and the backrest (2) is arranged to fastened to the backrest part (20). o 1/8 -. 0) ir: R 3 '6H £' 6H 4/8 7-b 01 913H LS 01 e-by 01 acz