Abstract
A bearing device (10) for a pointing device (1) and arranged between an operating cylinder (5) and its center shaft (6) to dampen/eliminate friction, vibrations and/or noises within or from the pointing device (1) can include an insulating bushing (12) formed of a damping material. The damping material can include at least in part fibers or is made of a fibrous material (13).
Claims
1-12. (canceled)
13. A bearing device (10) for a pointing device (1) and arranged between an operating cylinder (5) and a center shaft (6) thereof in order to dampen or eliminate friction, vibrations, or noises in or from the pointing device (1), the bearing device comprising: an insulating bushing (12) comprising a resilient, soft, or damping material, the resilient, soft, or damping material comprising a fibrous material (13), which makes the insulating bushing (12) soft and dampening to vibrations or noises.
14. The bearing device (10) according to claim 13, wherein the resilient, soft, or damping material is made of, or has a layer of, a low friction material.
15. The bearing device (10) according to claim 13, wherein the bushing (12) is arranged in a cylindrical bearing cup (9) which in turn is attached to the operating cylinder (5).
16. The bearing device (10) according to claim 13, wherein the bushing (12) is arranged inside the operating cylinder (5).
17. The bearing device (10) according to claim 13, wherein the insulating bushing (12) consists of at least one part.
18. The bearing device (10) according to claim 13, wherein the insulating bushing (12) is provided with a layer of glue (17).
19. The bearing device (10) according to claim 13, wherein the insulating bushing (12) is provided with a hard material in the form of a layer or coat (16) on the side abutting the center shaft (6).
20. The bearing device (10) according to claim 19, wherein the hard material of the layer or coat (16) consists of a ring which is fixed to the insulating bushing (12) and which ring is arranged between the insulating bushing (12) and the center shaft (6).
21. The bearing device (10) according to one of claim 19, wherein the layer or coat (16) comprises at least one of the materials from the group consisting of Polyamide, Polyester, Polyethylene, and Polytetrafluoroethylene (PTFE).
22. The bearing device (10) according to one of claim 20, wherein the layer or coat (16) comprises at least one of the materials from the group consisting of Polyamide, Polyester, Polyethylene, and Polytetrafluoroethylene (PTFE).
23. The bearing device (10) according to claim 13, wherein radial play between the bushing (12) and the center shaft (6), or between the bushing (12) and the operating cylinder (5), is at least 0.8 mm, resulting in that the friction, vibrations, or noises between these parts is further reduced.
Description
SHORT DESCRIPTION OF THE DRAWINGS
[0028] The invention is described in more detail below in some preferred embodiments with reference to the accompanying drawings.
[0029] FIG. 1 shows a pointing device in perspective obliquely from above.
[0030] FIG. 2 shows a pointing device in the corresponding perspective view as in FIG. 1, but here the upper housing part of the pointing device is removed.
[0031] FIG. 3 shows, in a corresponding perspective view as in FIGS. 1 and 2, a section through the operating cylinder and its center shaft and through some rear housing part of the pointing device.
[0032] FIG. 4 shows in perspective, obliquely from above, an example of an as not yet mounted insulating bushing in the form of a material mainly made of fibers.
[0033] FIG. 5 shows in a corresponding perspective view, as in FIGS. 1-3, in more detail an end portion of the operating cylinder, with a bearing cup surrounding the center shaft.
[0034] FIG. 6a shows in perspective view an exposed bearing device according to the invention.
[0035] FIG. 6b shows in perspective a section through the bearing device according to FIG. 6a.
[0036] FIG. 6c shows in perspective a section through an alternative embodiment of a bearing device.
[0037] FIG. 7a shows in perspective view a bearing device according to the invention corresponding to that shown in FIG. 6a and b but here arranged with an inner hard surface layer in the form of a ring, fixed to the inner surface of the insulating bushing.
[0038] FIG. 7b shows in perspective a section through the bearing device according to FIG. 7a.
[0039] FIG. 8 shows a section through a bearing device according to the invention and where the insulating bushing slides against the center shaft.
[0040] FIG. 9 shows a section through the operating cylinder and the center shaft shown in FIG. 8, but where the insulating bushing is provided with an alternative inner hard surface layer.
DESCRIPTION OF PREFERRED EMBODIMENTS
[0041] The present invention thus relates to a pointing device intended to enable axial and rotating movements of an operating cylinder mounted on a center shaft and with which operating cylinder a user can control a cursor/marker on a display/screen at for example a computer or similar electronic device.
[0042] FIG. 1 shows a pointing device 1 in perspective, obliquely from above. The pointing device 1 basically consists of a housing 2 or a cover which at its upper surface 3 can be provided with wrist support, buttons/keys for various functions, etc. (not shown). The pointing device 1 is intended to be located appropriately between a computer keyboard and a monitor/display/screen (not shown). The pointing device 1 mainly comprises an operating cylinder 5 which rotates/slides on a center shaft 6 which in turn can be a cylinder of smaller diameter (see for example FIG. 2). The center shaft 6 is at its end portions suitably fixedly arranged in the housing/chassis 7 of the pointing device. A user can manually actuate/maneuver the operating cylinder 5 through a control opening 8 arranged in the upper surface 3 of the pointing device 1 by rotating the operating cylinder 5 around its center shaft 6 or displacing it along the center shaft 6 with the hand/fingers and thereby control/move a cursor/marker on a connected computer monitor/display (not shown).
[0043] FIG. 2 shows a pointing device 1 in the corresponding perspective as in FIG. 1, but here the upper housing part is removed to show more clearly the location and construction of the operating cylinder device 4. The displaceable and rotatable operating cylinder 5 slides/rotates along/around the center shaft 6. The center shaft 6 is mechanically mounted at its end portions in the housing/chassis 7 of the pointing device in a suitable manner (not shown in detail). The figure shows how two cylindrical bearing cups 9 are mounted, one at each end of the operating cylinder 5 which by means of bearing devices 10 (see e.g. FIG. 3) allows the operating cylinder 5 to slide along, and rotate around, the center shaft 6.
[0044] FIG. 3 shows in a corresponding perspective view as FIGS. 1 and 2 a longitudinal section through the center shaft 6, the operating cylinder 5 and the bearing devices 10. A part of the upper rear part 11 of the housing is also visible here to illustrate how the center shaft 6 can be fixed to the housing at its end portions, but this is not important to this invention; the ends can be fastened for instance to click sensors (not shown) as well. As previously mentioned, the housing 3 is provided with an operating opening 8 which allows the user to reach the operating cylinder 5 with his hand or with his fingers. Bearing cups 9, here with substantially the same outer diameter as the actuating cylinder 5, are in this exemplary embodiment glued edge to edge to the actuating cylinder 5. Alternatively, the bearing cups 9 may be designed to be pressed slightly into the ends of the operating cylinder 5 (not shown).
[0045] Arranged in the bearing cups 9 are insulating bushings 12 located and mounted in such a way that they abut at least partially against the center shaft 6. In order to reduce the friction between the bearing devices 10 and the center shaft 6 as far as possible, a play may be allowed between the insulating bushing 12 and the center shaft 6 (not shown in detail). The play should typically be at least 0.8 mm but can be smaller or larger.
[0046] It should be clarified that the bearing cups 9 are not necessary for the function, they may be left out and the insulating bushings 12 are then fixed directly to the inside of the operating cylinder 5. The bearing cups 9 also do not have to be located at the ends of the operating cylinder 5, they can be located anywhere inside the operating cylinder 5.
[0047] It is essential that the weight of the operating cylinder 5 is low, and it can advantageously be made of aluminum, magnesium, carbon fiber or the like. Of course, other low-density, rigid materials can also be used. Said materials have the disadvantage, however, that they easily transmit sound vibrations to the environment mainly due to their relatively high stiffness.
[0048] According to the present invention, the problem of noise and vibration is solved in that the bearing device(s) 10 according to the invention are arranged to reduce the amount of vibrations occurring when the operating cylinder 5 is rotated around or slid along the center shaft 6, and in that the bearing devices 10 themselves dampen such vibrations or noises and do not lead them on to the operating cylinder 5. This eliminates or reduces the risk of vibrations/noises occurring in the construction being transmitted to the environment by the components of the pointing device 1.
[0049] The bearing cup 9 consists, as mentioned, of an outer ring made of a substantially hard material, such as e.g. of steel, aluminum, magnesium or similar.
[0050] FIG. 4 shows in perspective, obliquely from above, an example of a basic material for an insulating bushing 12 according to the invention which in mounted condition is placed in a bearing cup 9 or directly inside the operating cylinder 5. The insulating bushing 12 consist of, or comprises, a resilient/soft/damping material which is durable and having a low friction, advantageously a fibrous material 13 such as a woven fabric, felt or mat, alternatively a combination of these materials. The fibers themselves do not necessarily have to be made of a soft or damping material, but by arranging the fibers as a fabric 13 or as a blanket or mat, the insulating bushing 12 is given an advantageous damping function in the application according to the invention. The fabric 13 can be a thin fabric made of, for example, polyamide, which provides good wear resistance and low friction. Other materials, such as polyester or the like, are also fully possible to use. In unassembled condition, the insulating bushing 12 preferably consists of a long-narrow punched piece of such a soft/cushioning fabric 13 or fabric/felt/carpet. The insulating bushing 12 can advantageously be provided on one side with a thin layer of an adhesive, such as e.g. a heat adhesive, and is mounted by this against the inside of the bearing cup 9 or the operating cylinder 5 by means of a specially designed tool and simultaneous heating so that the insulating bushing 12 attaches to the bearing cup 9 or to the inside of the operating cylinder 5 and is thereby formed into a circular shape. A groove 14 or a gap (not shown) may be allowed to occur between the ends of the insulating bushing 12 in its mounted condition.
[0051] FIG. 5 shows in a corresponding perspective view as in FIGS. 1-3, in more detail, one end portion of the operating cylinder 5 and the center shaft 6. Here the bearing device 10 according to the invention is mounted in a bearing cup 9, which is fixed to the end portion of the operating cylinder 5 and which holds the actuating cylinder 5 at a certain distance in relation to the center shaft 6 but allows the actuating cylinder 5 to slide against or rotate about the center shaft 6. The bearing cup 9 is made of a substantially hard circular/cylindrical material. The bearing cup 9 can be pressed completely or partially into the ends of the operating cylinder 5 or alternatively fastened/glued to the end edges of the operating cylinder 5 and is thus mechanically fixedly arranged in/against the operating cylinder 5. It should be noted that the construction of the bearing device 10 with an inner softer insulating bushing 12, a substantial clearance may be allowed between the insulating bushing 12 and the center shaft 6, for example 0.8 mm. However, the gap can be both larger and smaller. A bearing device 10 of conventional type of e.g. hard plastic, such as polyethylene, gives rise to a disturbing “rattling” noise when the operating cylinder 5 e.g. is operated quickly by the user, provided that such a bearing device 10 is designed with a larger play (i.e. if it is manufactured with a substantially larger inner diameter compared to the outer diameter of the center shaft 6).
[0052] FIG. 6a shows in perspective view an exposed bearing device 10 according to the invention comprising a bearing cup 9 and a softer inner annular insulating bushing 12. The figure shows the ring of the bearing cup 9 in more detail and at its inside, the fixedly arranged and softer insulating bushing. The figure shows a gap 14 between the ends of the punched bushing material 12. This gap can in practice be for instance about 1 mm wide without compromising the function of the insulating bushing.
[0053] FIG. 6b shows in more detail the bearing device 10 according to the invention according to FIG. 6a, but here in section to show the constructive design of the bearing cup 9 and the insulating bushing 12 more clearly. The insulating bushing 12 thus consists of an inner ring of a substantially soft or cushioning material comprising a wear-resistant fibrous material. The insulating bushing 12 is fixedly arranged by means of an adhesive layer 17 at the bearing cup 9 and slides against the center shaft 6. The insulating bushing 12 may consist of one or more parts.
[0054] FIG. 6c shows in a section that the insulating bushing 12 does not necessarily have to be fixed to the bearing cup 9. The bearing cup 9 can for instance be made with a groove 15 which holds the insulating bushing 12 in place.
[0055] FIG. 7a shows in perspective view a bearing device 10 according to the invention corresponding to that shown in FIG. 6a and b but here also provided with an inner hard surface layer 16 in the form of a ring, fixed to the inner surface of the insulating bushing 12. This harder surface layer 16, may thus consist of a ring of a substance from the group of Polyamide, Polyester, Polyethylene, Teflon or the like and the purpose of this harder surface layer 16 is to reduce the friction further in the construction, at the same time as vibrations/noises from the bearing device 10 and the center shaft 6 still is damped by the insulating bushing 12.
[0056] FIG. 7b shows in perspective view and in a section corresponding bearing device 10 according to the invention shown in FIG. 7a. The adhesive layer 17 which fixes the insulating bushing 12 against the bearing cup 9 is also shown.
[0057] FIG. 8 shows in cross section a bearing device 10 according to the invention comprising an insulating bushing 12 mounted against the inside of the operating cylinder 5. The figure shows that there is a certain gap between the insulating bushing 12 and the center shaft 6, or the operating cylinder 5. This gap is typically about 0.8 mm but can be both larger and smaller. The gap is arranged to further reduce the risk for friction, vibration and/or noise. Also shown here is the adhesive layer 17 which fixes the insulating bushing 12 to the inside of the operating cylinder 5.
[0058] FIG. 9 shows that the inner harder layer/coat 16, can be provided by a coat/layer of e.g. a hard plastic. This hard plastic can be sprayed or brushed on the insulating bushing 12 in liquid form, or otherwise attached directly to the insulating bushing 12. Thin Teflon tape can also be used and fixed suitably via glue or self-adhesive to the insulating bushing 12.
[0059] Other embodiments are of course also possible within the scope of the presented inventive concept. The inner part of the bearing device 10 may consist of, or comprise, a substantially soft cushioning material of, for example, rubber. The surface of this material is advantageously in that case covered by a thin layer/layer of a harder material 16 with low friction such as e.g. Polyamide, Polyester, Teflon or the like which may be in the form of a fabric or a fabric/felt/mat or alternatively a hard ring as described above.
[0060] According to the invention, bearing devices 10 thus consist of the insulating bushing 12, with or without the harder layer/coat 16.
[0061] Of course, several layers of fibrous material can be used in the insulating bushing 12.
[0062] It is also conceivable to design a single long bearing device 10 (not shown) which is mounted between the center shaft 6 and the inside of the operating cylinder 5 as well as the insulating bushing 12, instead of being arranged in or against the inside of the operating cylinder 5, is mounted on the center shaft 6, preferably along the major part of the center shaft 6.
[0063] The above description is primarily intended to facilitate the understanding of the invention and the invention is of course not limited to the stated embodiments but also other variants of the invention are possible and conceivable within the scope of the inventive concept and the scope of the appended claims.
