Openable and closable device for a vehicle interior

Abstract: An opening and closing type interior device (10) includes a fixed member (11), a movable member (12) which is capable of being opened and closed and is movable relative to the fixed member (11), an actuator (15) including a driving source (13) and a gear mechanism (14), and a damper (16) coupled to one of the movable member (12) and the fixed member (11). The opening and closing type interior device (10) includes, for example, a display device for an automobile.

Description: The present invention relates to an interior device having an openable and closable movable member which is disposed, for example, in an automobile, and more particularly relates to a device having an operable and closable movable member which can suppress generation of noise. A typical conventional openable and closable device includes a display device for an automobile. The display device includes a fixed member, a movable member rotated about a rotational axis relative to the fixed member so as to be opened and closed, and an actuator for driving the movable member to rotate so as to be opened and closed. The actuator includes a driving source, and at least one gear (generally, a plurality of gears) disposed in a driving force transmission path. A backlash is provided in each engaging portion of gears. The backlash absorbs dimensional deviations between the gears, thermal expansion in the gears and the like, thereby securing an appropriate engagement between the gears. A further known device is described in EP-A-846886. This describes a device for dampening the movement of a pivotally supported structural part using a conventional rotary damper dampening a translatory movement. The device has a pivot arm attached to a structural part and linked to a straight rack. A pinion is mounted on the rotary damper and engages the rack. The rack has a linear guide which keeps the rack in engagement with the pinion. Movement of the structural part is thus dampened via the rotary damper. However, there is the following problem with the conventional device. When the movable member is opened and closed, a center of gravity of a movable assembly, which includes the movable member and a member or members rotatable together with the movable member, crosses above the rotational axis of the movable member and produces a moment. The moment caused about the rotational axis is due to the weight of the movable assembly and changes as the center of gravity of the movable assembly crosses above the rotational axis, so that the load imposed on the actuator for opening and closing the movable member reverses between a positive load and a negative load. As a result, the engagement of a driving side gear of the actuator with a driven side gear of the actuator is reversed, causing hammering in the gears due to the backlash of the gears thereby generating noise. An object of the present invention is to provide an interior device having an openable and closable movable member which can suppress noise generated due to backlash in gears. The present invention is constituted as follows. An interior device having an openable and closable movable member includes a fixed member, a movable member capable of being opened and closed and being movable relative to the fixed member, an actuator for driving the movable member to be opened and closed, and a damper coupled to one of the movable member and the fixed member. The actuator includes a driving source for driving the movable member and at least one gear mechanism disposed in a path transmitting a driving force from the driving source to the movable member. The movable member includes a rotational axis, and is rotatable about the rotational axis relative to the fixed member between a fully-opened and fully-closed position. The movable member, in cooperation with a member or members rotatable together with the movable member, constitutes a movable assembly having a center of gravity. The center of gravity of the movable assembly is located on one side of a vertical line passing through the rotational axis when the movable member is located at the fully-opened position, and is located on the other side of the vertical line passing through the rotational axis when the movable member is located at the fully-closed position. and the center of gravity crosses the vertical line passing through the rotational axis when the movable member is opened and closed. When the movable assembly, including the movable member and members rotatable together with the movable member, is opened and closed, the damper applies a load to the movable assembly in a direction suppressing the opening and closing motion thereby preventing the load imposed on the actuator from being reversed between positive and negative when the center of gravity of the movable assembly crosses the vertical line passing through the rotational axis of the movable member. As a result, the engagement of the driving side gear with the driven side gear of the actuator is prevented from being reversed, so that the noise generated due to the backlash of the gears is suppressed. The objects, features, and advantages of the present invention will become more apparent and will more readily be appreciated by the following detailed description of the preferred embodiments illustrated by the accompanying drawings, in which: FIG. 1 is a perspective view of device in a case where the device is a display device for an automobile according to an embodiment of the present invention; FIG. 2 is a side elevational view, as viewed from a bearing portion side. of the device in a case where the device is a display device for an automobile according to the embodiment of the present invention; FIG. 3 is a cross-sectional view of an actuator portion of the device in a case where the device is a display device for an automobile according to the embodiment of the present invention: FIG. 4 is a front elevational view of an actuator of the device in a case where the device is a display device for an automobile and the actuator is a geared motor according to the embodiment of the present invention; FIG. 5 is a front elevational view of an engaging portion of gears of the device in a case where the device is a display device for an automobile and the actuator is a geared motor; FIG. 6 is a side elevational view illustrating a positional relationship between a center of gravity of a movable assembly and a rotational axis of a movable member, which is applicable to both the present invention and a conventional device; FIG. 7 is a side elevational view, as viewed at a damper portion, of the device in a case where the device is a display device for an automobile according to the embodiment of the present invention; FIG. 8 is a side elevational view of a hydraulic damper of the device according to one embodiment of the present invention; FIG. 9 is a front elevational view of a hydraulic damper of the device according to one embodiment of the present invention; FIG. 10 is a side elevational view of a frictional damper of the device according to another embodiment of the present invention; FIG. 11 is a graph illustrating a relationship between the load imposed on the actuator and an opening and closing position of the movable member of the device in a case where the damper is the hydraulic damper according to the first embodiment of the present invention. FIG. 12 is a graph illustrating a relationship between the load imposed on the actuator and an opening and closing position of the movable member of the device in a case where the damper is the frictional damper according to the other embodiment of the present invention. FIGS. 1 - 12 illustrate an interior device having an openable and closable movable member according to an embodiment of the present invention. The device includes, for example, a device for an automobile. The device for an automobile includes, for example, a display device for an automobile. However, the device is not limited to the display device and may include a container for an automobile, an ash tray for an automobile and the like. In the drawings, the display device for an automobile is typically illustrated as an example, but the present invention is not necessarily limited thereto. As shown in FIGS. 1 - 5 and 7, an interior device having an openable and closable movable member 12 10 includes, a fixed member 11, a movable member 12 which is movable relative to the fixed member 11 and is capable of being opened and closed, an actuator 15 for driving the movable member to be opened and closed, and a damper 16 disposed in either the movable member 12 or the fixed member 11. The actuator 15 includes a driving source 13 for driving the movable member 12 and at least one gear mechanism 14 disposed in a path for transmitting a driving force from the driving power source 13 to the movable member 12. In a case where the device 10 is the display device for an automobile, the movable member 12 includes a casing 1, a display 2 and a door 3, which are connected integrally to each other. The movable member 12 includes a rotational axis 4, and rotates about the rotational axis 4 relative to the fixed member 11 to a fully-opened position or a fully-closed position. The actuator (for example, a geared motor) 15 and portions rotating about the rotational axis 4 including at least one gear mechanism 14 are fixed to or supported by the movable member 12, and are rotated about the rotational axis 4 together with the movable member 12 between an opened and closed position. The geared motor 15 includes a gear 14a constituting a part of the gear mechanism 14. A gear 14b is fixed to an output shaft of the actuator 15 protruding from the casing 1 and constitutes a part of the gear mechanism 14. The movable member 12, the actuator 15 and the portions rotatable about the rotational axis 4 including the gear mechanism 14 constitute a movable assembly 5. The movable assemble 5 has a center of gravity 9 located at a position spaced away from the rotational axis 4. More particularly, the center of gravity 9 of the movable assembly 5 is located on one side of a vertical line passing through the rotational axis 4 when the movable member 12 is fully-opened, and the center of gravity 9 is located on the other side of the vertical line passing through the rotational axis 4 when the movable member 12 is fully-closed. A locus of the center of gravity 9 of the movable assembly 5, at the time of opening and closing of the movable member 12, intersects the vertical line passing through the rotational axis 4 of the movable member 12. The center of gravity 9 of the movable assembly 5 crosses the vertical line passing through the rotational axis 4 of the movable member 12 when the movable member 12 is opened and closed. In FIG. 6, the center of gravity 9 passes just above the rotational axis 4 of the movable member 12, but the center of gravity 9 may pass just below the rotational axis 4 of the movable member 12. In the case where the device 10 is the display device for an automobile. the fixed member 11 includes right and left side members (rails) 6 and 7, and a retainer 8 connected to the side members 6 and 7. Bearings are disposed in the side members 6 and 7, and a shaft is disposed in the casing 1. The casing 1 is supported by the bearings of the side members 6 and 7 so as to be rotatable about the rotational axis 4. An arcuate gear 14c of an internal gear extending in an arc is fixed to the side members 6. The gear 14c engages a gear 14b fixed to the output shaft of the actuator 15. In the foregoing description, although the actuator 15 is fixed to the movable member 12 and the arcuate gear 14c of the internal gear is fixed to the fixed member 11, the actuator 15 may be fixed to the fixed member 11 and the arcuate gear 14c may be fixed to the movable member 12. A backlash, which is a clearance defined between a driving side gear and a driven side gear, is provided between each gear of the gear mechanism 14, for example, in the gear set 14a, or between the gear 14b and the gear 14c. FIG. 5 illustrates a backlash r of the gear 14a. The backlash r is provided between a worm as a driving side gear 14a-1 and a driven side gear 14a-2 in the case where the actuator 15 is the geared motor. Similarly, the backlash is provided between the gear 14b and the gear 14c. As shown in FIG. 7, the damper 16 is coupled to one of the movable member 12 and the fixed member 11. An internal gear 18 is coupled to the other of the movable member 12 and the fixed member 11 and extends in an arc. The damper 16 includes a shaft to which a gear 17 is coupled, and the gear 17 engages the arcuate internal gear 18. In FIG. 7, which shows the case where the device 10 is the display device for an automobile, the damper 16 is coupled to the fixed member 11 and the internal gear 18 is coupled to the movable member 12. Alternatively, the damper 16 may be fixed to the movable member 12 and the arcuate internal gear 18 may be fixed to the fixed member 11. In FIG. 7, which shows the case where the device 10 is the display device for an automobile, although the damper 16 is fixed to the side member 7 and the internal gear 18 is fixed to the casing 1, the damper 16 may be fixed to the side member 6. The damper 16 may be any kind of damper so long as the damper causes a resistance to rotation of the movable assembly 5. Preferably, the damper 16 is a hydraulic damper using fluid, for example oil, or a frictional damper. FIG. 11 illustrates the load characteristics in a case where the damper 16 is a hydraulic damper. FIG. 12 illustrates the load characteristics in a case where the damper is a frictional damper. The magnitude of the damper load is determined so that the summation (curve C of FIGS. 11 and 12) of the load (curve B of FIGS. 11 and 12) caused by a moment about the rotational axis 4 due to the weight of the movable assembly 5 acting on the center of gravity 9 of the movable assembly 5 and the load (curve A of FIGS. 11 and 12) caused by the damper 16 may not be reversed between a positive load and a negative load during rotation between the fully-opened position and the fully-closed position of the movable member 12. In the case where the damper 16 is a hydraulic damper using fluid, the speed is slow and the damper load is small at the beginning of the movement. The damper load becomes greater as the speed is accelerated. The magnitude of the damper load can be easily set to a desired value by optionally selecting the viscosity of oil, the number of fins of the damper 16, the magnitude of a clearance between the fin and the casing, and the like. In the case where the damper 16 is a frictional damper, the damper load does not vary, and constant. FIGS. 8 and 9 illustrate a structure of the damper 16 in a case where the damper 16 is a hydraulic damper of a viscous damping type. The damper 16 includes a casing 16a, a cap 16b fixed to the casing 16a, and a rotational shaft 16c. A portion 16d of the rotational shaft 16c has a fin-shaped configuration and is disposed in a space defined between the casing 16a and the cap 16b and filled with oil. When the rotational shaft 16c is rotated, the load generated causes the damping effect. The gear 17 is coupled to an outer end of the rotational shaft 16c. FIG. 10 illustrates a structure of the damper 16 in a case where the damper is a frictional damper. The damper 16 includes a casing 16a, a friction plate cap 16b fixed to the casing 16a, a rotational shaft 16c, and a spring washer 16e. A portion 16d of the rotational shaft 16c has a disk configuration. The portion 16d is disposed between the casing 16a and the cap 16b and is pushed to the friction plate cap 16b by the spring washer 16e. When the rotational shaft 16c is rotated, the load generated causes the damping effect. The gear 17 is coupled to an outer end of the rotational shaft 16. Next, operation according to the embodiments of the present invention will be explained. With the aforementioned structure, the gear 14b is rotated in normal and reverse directions by driving the actuator 15 normally and reversely, so that the movable assembly 5 is rotated to be opened and closed about the rotational axis 4, as shown in FIG. 6. The center of gravity 9 of the movable assembly 5 crosses the vertical line passing through the rotational axis 4 of the movable member 12 during the opening and closing motion of the movable member 12. In FIG. 6, the center of gravity 9 of the movable assembly 5 crosses above the rotational axis 4. A conventional device in which a damper is not provided has the following problem, which will be explained with reference to FIG. 6. The load imposed on the actuator 15 changes according to an opening and closing angle of the movable member 12, and the load changes according to a positional relationship between the center of gravity 9 of the movable assembly 5 and the rotational axis 4, as shown in FIG. 6. When the actuator 15 is driven in a direction to open the movable member 12, a positive load (moment) is at first imposed on the actuator 15 to drive the movable assembly 5. After the center of gravity 9 of the movable assembly 5 crosses above the rotational axis 4, a moment opening the movable assembly 5 by itself is generated, so that a negative load (moment) is imposed on the actuator 15. At that time, the engagement of a driving side gear with a driven side gear is reversed. As a result, the actuator 15 is rotated reversely by the amount of the backlash causing hammering, which generates noise. In contrast, in the present invention in which the damper 16 is provided. as illustrated in FIGS. 11 and 12, when the movable assembly 5 is opened and closed by the actuator 15, the load (curve A of FIGS. 11 and 12) is imposed on the actuator 15 by the damper 16. The load imposed on the actuator by the moment caused about the rotational axis due to the weight of the movable assembly 5 acting on the center of gravity 9 of the movable assembly 5 (curve B of FIGS. 11 and 12) changes as the center of gravity 9 is moved according to the opening and closing position of the movable assembly 5 and is reversed between positive and negative when the center of gravity 9 of the movable assembly 5 crosses the vertical line passing through the rotational axis 4. The total value of the load imposed on the actuator 15 (curve C which is a summation of curve A and curve B of FIGS. 11 and 12) is not reversed between positive and negative in the entire rotational range between the fully-opened position and the fully-closed position. Accordingly, the noise generated by the backlash of gears 14a, 14b and 14c when the load is reversed between positive and negative can be effectively eliminated, or, at least suppressed, during either opening or closing. In the case where the damper 16 is a hydraulic damper, the damper load changes according to the opening and closing speed of the movable assembly 5. At the beginning of the movement, the speed is slow and the damper load is small. As the opening and closing motion progresses and the speed of the movable assembly 5 accelerates, the load of the damper 16 becomes large. Therefore, the total value of the load imposed on the actuator 15 is not reversed between positive and negative, and the load fluctuates less. Further, since the damper load is small at the beginning of the movement, a torque of the actuator 15, especially, a starting torque is only slightly reduced, so that an intensity of the torque of the actuator 15 is not necessary as compared with the conventional actuator. According to the present invention, the following technical advantages are obtained. First, since the device is provided with the damper, when the movable assembly including the movable member is driven between opened and closed, the damper applies a load to the movable assembly in a direction suppressing the opening and closing motion to thereby prevent the load imposed on the actuator from being reversed between a positive load and a negative load when the center of gravity of the movable assembly crosses the vertical line passing through the rotational axis of the movable member. As a result, the engagement of the driving side gear with the driven side gear of the actuator is prevented from being reversed, so that noise due to the backlash of the gear can be suppressed. Second, in the case where the damper is a hydraulic damper using fluid, the damper load generated is small at the beginning of the movement, so that the starting torque of the actuator is only reduced slightly. Therefore, increasing the torque of the actuator is not necessary. Though described and illustrated here in relation to an interior device of an automobile, the invention is applicable to any device having a reversible rotary driving motion in which the centre of gravity of the movable member shifts as herein described.

Claims: An interior device (10) having an openable and closable movable member (12), comprising: a fixed member (11); said movable member (12) being movable relative to said fixed member (11); and a damper (16) coupled to one of said movable member (12) and said fixed member (11), wherein said movable member (12) has a rotational axis (4), said movable member (12) being rotatable about said rotational axis (4) relative to said fixed member (11) to fully opened and fully closed positions, said movable member (12) and any member rotatable together with said movable member (12) constituting a movable assembly (5) having a center of gravity (9), said center of gravity (9) of said movable assembly (12) being located to one side of a vertical line passing through said rotational axis (4) when said movable member (12) is located at said fully opened position and being located to the other side of the vertical line passing through said rotational axis (4) when said movable member (12) is located at said fully closed position, said center of gravity (9) crossing the vertical line passing through said rotational axis (4) when said movable member (12) is opened and closed, characterized by an actuator (15) for driving said movable member (12) to be opened and closed, said actuator (15) including a driving source (13) for driving said movable member (12) and at least one gear mechanism (14) for transmitting a driving force from said driving source (13) to said movable member (12), and in that the magnitude of the load generated by said damper (16) is determined so that a summation of the load imposed on said actuator (15) by a moment caused about said rotational axis (4) due to the weight of said movable assembly (12) acting on said center of gravity (9) of said movable assembly (12) and a damper load imposed on said actuator (15) by said damper (16) is not reversed between positive and negative while said movable member (12) is rotated between said fully opened position and said fully closed position. A device (10) according to claim 1, wherein said damper (16) is a hydraulic damper. A device (10) according to claim 1, wherein said damper (16) is a frictional damper. A device (10) according to claim 1 or claim 2, wherein said damper (16) includes a casing (16a) and a cap (16b) having a space defined between said casing (16a) and said cap (16b) filled with oil, a fin portion (16d) inserted into the space filled with oil, and a rotational shaft (16c) connected to said fin portion (16d) and protruding from said casing (16a) and said cap (16b). A device (10) according to any one of the preceding claims, further comprising a first internal arcuate gear (18) extending in an arc, wherein said damper (16) includes a rotational shaft and a gear (17) fixed to said rotational shaft, said gear (17) of said damper (16) engaging said first arcuate gear (18), one of said damper (16) and said first arcuate gear (18) being fixed to said movable member (12) and the other of said damper (16) and said first arcuate gear (18) being fixed to said fixed member (11). A device (10) according to any one of the preceding claims, wherein said actuator (15) is supported by one of said movable member (12) and said fixed member (11) and includes a geared motor (15) having a driving side gear (14a-1) and a driven side gear (14a-2), said actuator (15) having an output shaft to which a gear (14b) is fixed, a second internal arcuate gear (14c) engaging said output shaft gear (14b), said at least one gear mechanism (14) including a first gear mechanism of said driving side gear (14a-1) and driven side gear (14a-2) of said geared motor (15) and a second gear mechanism of said output shaft gear (14b) and said second internal arcuate gear (14c), wherein said second arcuate gear (14c) is fixed to the other of said movable member (12) and said fixed member (11). A device (10) according to any one of the preceding claims, wherein said device is a display device for an automobile.

Inventors: OJI KENICHI, TSUKADA MASASHI, OJI, KENICHI, TSUKADA, MASASHI
Applicants: KOJIMA PRESS KOGYO KK, KOJIMA PRESS INDUSTRY CO., LTD.
Application year: 1999
Main classification: B60K35
IPC codes: G09F9, E05F3, B60R11, B60K35