JP2007032772A - Linear actuator - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a linear actuator of a simple structure in which a bearing member can be held, while ensuring the strength of the bearing-holding member. <P>SOLUTION: In the linear actuator 12R constituting a linear actuator device 10, when a feed screw shaft 36 inserted in the main-body housing 24 is rotated, a nut 38 screwed on the feed screw shaft 36 is put in a linear motion. A bearing 42 supporting the rear end 36A of the feed-screw shaft 36 is supported by being caught between an annular wall 118B of an end-housing 22 and a plurality of holding pins 125 provided projectingly from the rear-end face 24D of the main-body housing. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a linear actuator that linearly drives a rod member along a longitudinal direction.

There is known a linear actuator that converts a rotational motion of an electric motor into a linear motion along the longitudinal direction of a rod member (see, for example, Patent Document 1). Patent Document 1 describes a configuration in which a rotary motion of an electric motor is converted into a linear motion of an operating rod by a feed screw mechanism. In this configuration, the spindle that is housed in the outer tube (housing) and the console (cover member) and constitutes the feed screw mechanism is rotatably supported by the ball bearing at the axial end protruding from the console. The ball bearing is held in the rear mount in both the thrust direction and the radial direction by being encapsulated in a recess of the rear mount formed by joining the half parts.
JP-T-2004-511194

  However, since the conventional linear actuator as described above has a structure in which the ball bearing is encapsulated in the recess, the structure in which the rear mount is a separate part from the console and is configured by a half part divided in the radial direction. (A structure with a three-piece cover member). For this reason, there is a problem that the structure is complicated and the strength of the holding portion of the ball bearing (the fixed side of the linear actuator) depends on the joining strength of the half parts.

  An object of the present invention is to obtain a linear actuator capable of holding a bearing member with a simple structure while ensuring the strength of the bearing holding member in consideration of the above facts.

  In order to achieve the above object, a linear actuator according to a first aspect of the present invention includes a rotating shaft that linearly moves an output member by rotating around an axis, a housing into which the rotating shaft is inserted, and a rotating shaft. A bearing member for rotatably supporting an axial end projecting from the open end of the housing; a bearing holding member fixed to the axially outer side of the open end of the housing; and projecting from the open end of the housing And a plurality of holding projections sandwiching the bearing member with the bearing holding member.

  In the linear actuator according to the first aspect, when the rotating shaft rotates around the axis, the output member linearly moves. The rotating shaft is supported by a bearing member at the axial end projecting out of the housing, and the bearing member is sandwiched between the holding projection projecting from the opening end of the housing and the bearing holding member, It is supported. Thereby, the rotating shaft is rotatably supported with respect to the housing via the bearing member.

  Here, since the bearing member is sandwiched and held between the holding convex portion protruding from the opening end of the housing and the bearing holding member, the bearing member is supported (held) with respect to the housing with a simple structure. can do. Further, since the bearing holding member is not a structure that restricts the movement of the bearing member in the thrust direction alone, the bearing holding member does not have to be divided into two in the radial direction of the rotating shaft, and the strength is ensured. be able to.

  Thus, the linear actuator according to claim 1 can hold the bearing member with a simple structure while ensuring the strength of the bearing holding member.

  A linear actuator according to a second aspect of the present invention is the linear actuator according to the first aspect, wherein the holding convex portion is configured by embedding a longitudinal end portion of the pin-shaped member in an opening end of the housing.

  In the linear actuator according to the second aspect, since the holding convex portion is formed by embedding the pin-shaped member in the opening end of the housing, the structure is simple. In particular, in the configuration in which the housing is molded using a mold, it is not necessary to integrally form the holding convex portion, so that the mold structure is prevented from becoming complicated.

  A linear actuator according to a third aspect of the present invention is the linear actuator according to the second aspect, wherein the pin-shaped member is embedded in the open end of the housing by press fitting.

  In the linear actuator according to the third aspect, since the pin-shaped member is embedded in the opening end of the housing by press-fitting, the operation of providing the holding convex portion is easy as compared with a configuration using, for example, screwing or bonding.

  A linear actuator according to a fourth aspect of the present invention is the linear actuator according to any one of the first to third aspects, wherein the bearing holding member houses the bearing member and closes the open end of the housing. It is a cover member to do.

  In the linear actuator according to claim 4, since the cover member is a bearing holding member (also serves as a bearing holding member), the bearing member can be held with a simple structure while ensuring the strength of the bearing holding member without increasing the number of parts. it can.

  A linear actuator according to a fifth aspect of the present invention is the linear actuator according to any one of the first to third aspects, wherein the linear actuator has a larger diameter than the rotary shaft, and the opening end of the housing and the bearing A driven-side external gear that is provided coaxially with the rotary shaft between the member and for transmitting a rotational force to the rotary shaft; and a drive-side gear meshed with the driven-side external gear. The plurality of holding projections are provided in three or more, and are arranged radially outside the driven-side external gear and at an interval of less than 180 ° while avoiding the installation position of the driving-side gear.

  In the linear actuator according to the fifth aspect, when the drive side gear rotates, the driven side external gear rotates, and this rotation is transmitted to the rotation shaft, and the rotation shaft rotates around the axis. The three or more holding convex portions sandwich different portions in the circumferential direction of the bearing member between the bearing holding member without interfering with the driven-side external gear and the driving-side gear, respectively. Even when three or more holding projections cannot be arranged at equal intervals due to the presence of the driving side gear meshing with the outer periphery of the driven-side external gear, the interval between the holding projections adjacent in the circumferential direction is less than 180 °. Therefore, the bearing member can be stably held.

  A linear actuator according to a sixth aspect of the present invention is the linear actuator according to the fifth aspect, wherein the driven-side external gear is a worm wheel and the drive-side gear is a worm.

  In the linear actuator according to claim 6, the meshing portion of the worm and the worm wheel is longer in the circumferential direction of the worm wheel (driven external gear) than the meshing portion of the spur gear train for reduction. By disposing three or more holding convex portions as described above, the bearing member can be stably held without interfering with these meshing portions.

  A linear actuator according to a seventh aspect of the present invention is the linear actuator according to the fifth or sixth aspect, wherein the bearing holding member houses the bearing member, the driven-side external gear, and the driving-side gear. A cover member for closing an open end of the housing;

  In the linear actuator according to claim 7, since the cover member is a bearing holding member (also serves as a bearing holding member), the bearing member can be held with a simple structure while ensuring the strength of the bearing holding member without increasing the number of parts. it can. In addition, the driven-side external gear (worm wheel) and the bearing member can be arranged close to each other, and the entire linear actuator can be made compact.

  The linear actuator according to an eighth aspect of the present invention is the linear actuator according to the fourth or seventh aspect, wherein the cover member has a temporary holding portion for temporarily holding the bearing member, and the cover member is disposed in the housing. The bearing member is sandwiched between the cover member and the holding convex portion by the operation of assembling.

  In the linear actuator according to claim 8, when the bearing cover member is moved to the housing side along the axial direction of the rotation shaft, each holding convex portion comes into contact with the bearing member temporarily held by the cover member, and the cover member is moved to the housing. If it fixes to, the bearing member will be in the holding state inserted | pinched between a cover member and each holding | maintenance convex part. Thus, the assembly direction of each component is the direction along the axial direction of the rotating shaft, so that the assembly work is easy. Further, assembly by automatic assembly is also easy.

  A linear actuator according to an ninth aspect of the present invention is the linear actuator according to the eighth aspect, wherein the temporary holding portion is a radial support portion that restricts radial movement of the bearing member in the cover member.

  In the linear actuator according to the ninth aspect, the radial movement of the cover member is restricted by the radial support portion of the cover member, and the movement of the bearing member in the axial direction is restricted between the cover member and the holding convex portion as described above. ing. Since the radial support portion also serves as the temporary holding portion, the structure is simple.

  The linear actuator according to claim 10 is the linear actuator according to claim 9, wherein the bearing member has a circular outer periphery that is coaxial with the rotation shaft when viewed from the axial direction of the rotation shaft. The radial support portion of the cover member is a recess into which the bearing member is fitted.

  In the linear actuator according to the tenth aspect, since the directivity when the bearing member is fitted into the concave portion of the cover member does not become a problem, the assembling work is further facilitated.

  The linear actuator according to an eleventh aspect of the present invention is the linear actuator according to any one of the first to tenth aspects, wherein the bearing member includes an inner ring and an outer ring that are coaxially rotatable. The inner ring is fitted to the rotating shaft, and the outer ring is sandwiched between the bearing holding member and the holding convex portion.

  In the linear actuator according to the eleventh aspect, the outer ring of the bearing member is sandwiched between the bearing holding member (cover member) and the plurality of holding convex portions, so that the bearing member having the inner and outer rings is simply disposed in the concave portion. Compared to the configuration, the play is small in both the radial direction and the thrust direction. As described above, the present invention is suitably applied when using a bearing member having inner and outer rings that rotate relative to each other, such as a rolling bearing.

  A linear actuator device 10 according to an embodiment of the present invention will be described with reference to FIGS. First, the schematic overall configuration of the linear actuator device 10 will be described, then the detailed configuration of the rotary / linear motion conversion mechanism 18 including the main part of the present invention will be described, and then the linear actuator device 10 was applied to the liftable toilet seat device 80. An example will be described. For convenience of explanation, the direction indicated by the arrow A in each drawing is the forward direction, that is, the direction facing the person sitting on the toilet seat 86 of the liftable toilet seat device 80, the direction indicated by the arrow B is the upward direction, When using the direction, the left-right direction for the seated person is used.

(Overall configuration of linear actuator)
As shown in FIG. 9, the linear actuator device 10 includes a pair of linear actuators 12 </ b> L and 12 </ b> R configured separately from each other. Each of the linear actuators 12R and 12L independently corresponds to the linear actuator in the present invention.

  As shown in FIGS. 9 and 10, the linear actuators 12L and 12R are provided with drive mechanisms 14L and 14R. The drive mechanisms 14L and 14R have the same configuration in the present embodiment. . As shown in FIGS. 10 and 11, the drive mechanisms 14L and 14R are a drive motor 16, a rotation / linear motion conversion mechanism 18, an output rod 20 (rod), an end housing 22, a main body housing 24, a front housing 26, and a position detection. A substrate 28 is provided.

  The drive motor 16 is composed of a DC motor such as a motor with a brush, for example, and is fixed to the lower end of the end housing 22. In addition, a rotation speed detector 17 is built in the drive motor 16, and the rotation speed detector 17 generates a pulse every rotation of the drive motor 16. The drive motor 16 is provided with a power supply connector 30.

  The rotation / linear motion conversion mechanism 18 converts the rotational drive force of the drive motor 16 into a drive force of linear motion, and moves the output rod 20 as a rod member forward and backward. As shown in FIG. 11, the drive motor A worm 33 as a “driving side gear” formed on a rotating shaft 32 rotated by the worm 16, a worm wheel 34 as a “driven side external gear” meshed with the worm 33, and coaxial with the worm wheel 34. A feed screw shaft 36 provided integrally and a nut 38 screwed to the feed screw shaft 36 are provided.

  In the guide groove 46 recessed in the outer peripheral portion of the nut 38, a guide rail 48 projecting from the inner peripheral surface of the main body housing 24 over substantially the entire length is slidably inserted in the axial direction. The main body housing 24 is prevented from rotating. Further, as shown in FIG. 11, the abutting portion 21 that abuts on an all-advance position detection switch 50 or an all-storage position detection switch 52 provided on a position detection board 28 described later is provided at the upper end of the nut 38. ing.

  Fixed to the nut 38 is a rear end 20A of the output rod 20 formed in a cylindrical shape that penetrates the front end of the main body housing 24 and coaxially enters the front end side of the feed screw shaft 36. In addition, the front end of the output rod 20 that is always located outside the main body housing 24 is connected to the first link member 96L of the link mechanism portions 94L and 94R provided in a liftable toilet seat device 80 (see FIGS. 13 and 14) described later. , 96R is provided with a movable side connection portion 23 that is rotatably connected and fixed. The movable side connecting portion 23 is formed in a substantially cylindrical shape, and has a link coupling connecting hole 23A and a relief slit 23B for the first link members 96L and 96R.

  As described above, in the rotation / linear motion conversion mechanism 18, when the drive motor 16 rotates, the worm 33 rotates. When the worm wheel 34 and the feed screw shaft 36 rotate due to the rotation of the worm 33, the nut 38 moves in the axial direction together with the output rod 20. It is supposed to move. In this embodiment, the rotation / linear motion conversion mechanism 18 is configured to convert the rotation of the rotary shaft 32 disposed along the vertical direction of the drive motor 16 into a linear motion of the output rod 20 in a substantially front-rear direction (horizontal direction). It is. The feed screw shaft 36 corresponds to the “rotary shaft” in the present invention, and the nut 38 or the output rod 20 corresponds to the “output member” in the present invention.

  Further, in this embodiment, the rotation / linear motion converting mechanism 18 moves the output rod 20 forward (extends with respect to the main body housing 24) by forward rotation of the drive motor 16, and retracts the output rod 20 by reverse rotation of the drive motor 16. It has become. That is, each drive mechanism 14L, 14R housed in housing cases 40L, 40R described later has an output rod 20 in which the movable side connecting portion 23 is positioned outside the housing cases 40L, 40R. It is designed to expand and contract.

  In the rotation / linear motion conversion mechanism 18, the self-lock is generated in which the linear motion of the nut 38 cannot be converted into the rotation of the feed screw shaft 36. Further, the worm gear composed of the worm 33 and the worm wheel 34 is set to generate a self-lock that cannot transmit rotation on the speed increasing side.

  The end housing 22 houses a worm 33 and a worm wheel 34 that are meshed with each other. In the end housing 22, a bearing 42 for supporting the feed screw shaft 36 so as to be rotatable around the axis is accommodated and held. This holding rod will be described in detail later. Further, the end housing 22 is provided with a fixed-side connection portion 44 that is rotatably connected and fixed to fixed leg portions 90L and 90R of a main body base member 88 provided in an elevating toilet seat device 80 described later. The fixed-side connecting portion 44 has a connecting hole 44A for link connection to the fixed leg portions 90L and 90R, and a slit 44B for allowing relative angular displacement.

  A main body housing 24 is fixed to a front end of the end housing 22 with a screw 25 as a fixing tool, and a front housing 26 is fixed to a front side of the main body housing 24 with a screw 27 as a fixing tool. It is fixed. The front housing 26 has a through hole 26A through which the output rod 20 is inserted, and supports the output rod 20 slidably in the axial direction at the hole edge of the through hole 26A.

  Further, a feed screw shaft 36 whose rear end is held by the end housing 22 is inserted into the main body housing 24, and the front end of the feed screw shaft 36 is connected to the output rod 20 via a bearing 49 (see FIG. 11). It is in contact with the inner peripheral surface so as to be relatively rotatable and slidable in the axial direction. That is, the front end of the feed screw shaft 36 is supported by the front housing 26 via the bearing 49 and the output rod 20. As described above, the guide rail 48 that engages with the guide groove 46 of the nut 38 is formed along the longitudinal direction inside the main body housing 24.

  The position detection board 28 detects the fully advanced position and the fully retracted position of the output rod 20, and when the output rod 20 is fully advanced, the fully advanced position detection switch 50 that contacts the contact portion 21 of the nut 38 is provided at the front end. In addition to being provided in the vicinity, an all-storage position detection switch 52 that contacts the contact portion 21 when the output rod 20 is fully stored is provided in the vicinity of the rear end. The position detection board 28 is disposed above the feed screw shaft 36 in the main body housing 24, and one end thereof is supported by the end housing 22 and the other end is supported by the front housing 26.

  In addition, on the rear side of the all-storage position detection switch 52 on the position detection board 28, there is a connector 31 for outputting detection signals of the all-advance position detection switch 50 and the all-storage position detection switch 52 to a control circuit board 66 described later. Is provided. As shown in FIGS. 10 and 11, the connector 31 is exposed from the connector housing portion 22 </ b> A formed integrally with the upper end of the end housing 22.

  The drive units 14R and 14L described above are accommodated and held in the corresponding housing cases 40R and 40L so that the movement direction of the output rod 20 substantially coincides with the horizontal direction. The connection part 23 side and the fixed side connection part 44 penetrate the housing cases 40R and 40L and protrude outside. The output rod 20 is in contact with a seal member (not shown) provided in the through portion of the housing cases 40R and 40L so as to be slidable in the axial direction. The drive units 14R and 14L have a main body housing 24 formed in a substantially rectangular container shape arranged at the upper part in the housing cases 40R and 40L, and the drive motor 16 arranged at the rear part in the housing cases 40R and 40L. .

  As shown in FIG. 9, a power supply circuit portion 54 is accommodated in the housing case 40R of the linear actuator 12R. The power supply circuit unit 54 is disposed in the space below the drive unit 14R and in front of the drive motor 16 in the housing case 40R. The power supply circuit unit 54 receives power supply (for example, AC100V) from the external power supply 60 (see FIG. 12), and supplies power (for example, DC24V) necessary for driving each of the pair of linear actuators 12L and 12R, that is, the drive motors 16. ).

  As shown in FIG. 12, the power supply circuit unit 54 of the present embodiment is provided with a power supply circuit board 56 provided with a power supply circuit, and the power supply circuit board 56 is provided with connectors 58 </ b> A to 58 </ b> D. ing. A power cable 62 extending from the external power source 60 is connected to the connector 58A, whereby the power circuit board 56 receives power from the external power source 60.

  Further, the power supply circuit unit 54 is provided with a transformer 64 for transforming the voltage supplied from the external power supply 60. A wiring member extending from the transformer 64 is connected to the power supply circuit board 56 via connectors 58C and 58D. Connected. In the present embodiment, the transformer 64 is also disposed in the housing case 40R.

  On the other hand, as shown in FIG. 9, a control circuit board 66 provided with a control circuit is housed in the housing case 40L of the linear actuator 12L. The control circuit board 66 is disposed in the space below the drive unit 14L and in front of the drive motor 16 in the housing case 40L. The control circuit of the control circuit board 66 (hereinafter simply referred to as the control circuit board 66) is configured to control each of the pair of linear actuators 12L and 12R based on the power supply from the power supply circuit unit 54.

  As shown in FIG. 12, the control circuit board 66 is provided with connectors 68A to 68G. The connector 68A is for motor output, and is connected to the connector 30 provided on the drive motor 16 of the linear actuator 12R via a connection cable 72. The connector 68B is for inputting a position detection signal, and is connected to the connector 31 provided on the position detection board 28 of the linear actuator 12R via a connection cable 72. In the present embodiment, the connection cable 72 is configured as one wire harness that connects the power supply circuit board 56 and the control circuit board 66 of the power supply circuit section 54, as shown in FIG.

  The connector 68C is for motor output. As shown in FIG. 12, the connector 68C is connected to the connector 30 provided on the drive motor 16 of the linear actuator 12L via a connection cable 73A, and the connector 68D is for position detection signal input. And connected to the connector 31 provided on the position detection board 28 of the linear actuator 12L via the connection cable 73B.

  The connector 68E is for power supply input and is connected to the connector 58B of the power supply circuit section 54 via the connection cable 72. The connectors 68F and 68G are for operation signal input, and are respectively a hand switch 70A and a foot switch 70B. Connected to.

  Control by the control circuit board 66 will be described later together with the configuration of the liftable toilet seat device 80.

(Detailed configuration of rotation / linear motion conversion mechanism)
FIG. 4 shows a rear view of the main body housing 24. As shown in this figure, the main body housing 24 is formed in a cylindrical shape having a substantially drop-like outer edge shape when viewed from the axial direction. In the main body housing 24, a feed screw shaft 36 is inserted in the lower part and a motion conversion space 24 </ b> A for reciprocating the nut 38 and a board installation space for arranging the position detection board 28 in the upper part are disposed. A communication space 24C that connects the motion conversion space 24A and the substrate installation space 24B is formed.

  In the motion conversion space 24A, a plurality of the above-described guide rails 48 protrude from the main body housing 24 (the peripheral wall thereof). In this embodiment, three guide rails 48 are provided, and the communication space 24C is formed by cutting out the guide rail 48 located between the motion conversion space 24A and the substrate installation space 24B. Therefore, it is possible to grasp that four guide rails 48 are provided.

  The three guide rails 48 are respectively formed with screw holes 48A into which the screws 25 are screwed. As shown in FIG. 11, the screw hole 48 </ b> A is also formed at the front opening end of the main body housing 24, and the screw 27 is screwed into the screw hole 48 </ b> A.

  A pair of left and right slits 110 for supporting the position detection board 28 is formed in the upper part of the board installation space 24B. The position detection board 28 is inserted into each slit 110 from the rear end side and set in the main body housing 24. At this time, the swing arm portions 50A and 52A (see FIGS. 4 and 6) of the all advanced position detection switch 50 and all stored position detection switch 52 pass through the communication space 24C.

  As shown in FIGS. 6 and 7, the front end of the position detection board 28 is held between a pair of upper and lower engagement protrusions 112 protruding rearward from the back surface of the front housing 26. A configuration in which the front end of the position detection board 28 enters between the engagement protrusions 112 in accordance with the attaching operation of the front housing 26 to the main body housing 24 or in the main body housing to which the front housing 26 is attached. It is.

  On the other hand, as shown in FIGS. 1 and 2, the rear end of the position detection board 28 enters and is held in the recess 114 provided in the rear wall 22 </ b> B of the connector housing portion 22 </ b> A in the end housing 22. . The front end of the position detection board 28 is configured to enter between the recesses 114 as the end housing 22 is attached to the main body housing 24.

  Further, as shown in FIG. 5, the lower portion of the communication space 24 </ b> C of the main body housing 24 is provided with a contact portion 21 protruding from the nut 38, and the arm of the full advance position detection switch 50 and the full storage position detection switch 52. The parts 50A and 52A can be contacted. The all advanced position detection switch 50 and the all retracted position detection switch 52 are configured to output detection signals when the swinging arm portions 50A and 52A are pushed up by the contact portion 21.

  As shown in FIGS. 6 and 7, a cover member 116 that restricts the downward swing of the swing arm portion 50 </ b> A of the all-advance position detection switch 50 is attached to the position detection board 28. The cover material 116 is formed in a U-shape that opens upward so as to cover the front portion of the swing arm portion 50A from below. When the abutting portion 21 moving forward as shown in FIG. 8 (A) passes through the swing arm portion 50A and moves backward as shown in FIG. The contact portion 21 can push up the swing arm portion 50A. When the cover member 116 is not provided, the contact portion 21 that moves forward as shown in FIG. 8C passes through the swing arm portion 50A and moves backward as shown in FIG. 8D. When moving, there may occur a phenomenon that the backward movement of the contact portion 21 is hindered when the swinging arm portion 21 is rotated downward.

  As shown in FIGS. 1 to 3, in the end housing 22, there are a bearing insertion portion 118 in which the bearing 42 is accommodated and a wheel accommodation portion 120 in which the worm wheel 34 is accommodated in the front-rear direction (of the feed screw shaft 36. Axis direction). Further, a worm accommodating part 122 for accommodating the worm 33 is provided on the side of the wheel accommodating part 120 in the end housing 22, and the worm accommodating part 122 is connected to the wheel accommodating part 120 via a window part 124. The worm 33 and the worm wheel 34 are communicated with each other so that they can be engaged with each other. FIG. 2 is an exploded perspective view before the output rod 20 is assembled.

  As shown in FIGS. 1 and 2, the bearing 42 includes an inner ring 42 </ b> A fitted to the rear end 36 </ b> A of the feed screw shaft 36 and an outer ring 42 </ b> B fitted to the bearing fitting portion 118 of the end housing 22. It is configured to be smoothly and relatively rotatable via balls and rollers. The outer diameter of the outer ring 42 </ b> B is larger than the outer diameter of the worm wheel 34.

  As schematically shown in FIG. 3, the bearing insertion portion 118 includes a cylindrical surface portion 118A coaxial with the feed screw shaft 36 with which the outer ring 42B is fitted, and an annular wall that defines the rear end and abuts the outer ring 42B. Part 118B, and a relief space 118C for escaping the rear end 36A of the feed screw shaft 36 located on the radially inner side of the annular wall part 118B and projecting rearward of the inner ring 42A. Therefore, the bearing 42 inserted into the bearing insertion portion 118 and having the outer ring 42B brought into contact with the annular wall portion 118B is restricted from moving in the radial direction and the rearward direction.

  In the end housing 22, a fitting portion 22 </ b> D (see Zu 2) protruding forward from the front end surface 22 </ b> C is fitted into the motion conversion space 24 </ b> A of the main body housing 24, and the front end surface 22 </ b> C is opened to the rear side of the main body housing 24. The screw 25 penetrating through itself is screwed into (threaded into) the screw hole 48 </ b> A in a state of being abutted against the end 24 </ b> D, thereby being fixedly attached to the main body housing 24.

  Here, as shown in FIGS. 1 to 3, in the rotation / linear motion conversion mechanism 18, the holding pins 125 as a plurality of “holding protrusions” protruding rearward from the rear opening end 24 </ b> D of the main body housing 24. Thus, the forward movement of the bearing 42 is restricted. Each holding pin 125 is provided along the longitudinal direction of the main body housing 24, that is, the axial direction of the feed screw shaft 36.

  Specifically, the plurality of holding pins 125 are disposed along a virtual circumference that is larger than the outer diameter of the worm wheel 34 and smaller than the outer diameter of the outer ring 42B of the bearing 42, and each has a rear end. The bearing 42 is brought into contact with the front surface of the outer ring 42B. Thus, when the end housing 22 is attached to the main body housing 24 with the screw 25, the outer ring 42B of the bearing 42 is sandwiched between the annular wall portion 118B of the end housing 22 and each holding pin 125, and forward of the bearing 42. Movement is regulated.

  In this embodiment, the holding pins 125 protrude from the respective guide rails 48 at the rear opening end 24 </ b> D of the main body housing 24 to be a total of three. Further, as shown in FIG. 4, the holding pins 125 are arranged at unequal intervals in the circumferential direction so as to avoid the worm 33 meshing with the worm wheel 34. The holding pins 125 are arranged so that the holding pins 125 adjacent in the circumferential direction are present at a position of less than 180 ° around the axis of the bearing 42 (feed screw shaft 36).

  Each holding pin 125 is comprised, for example with metal wires, such as stainless steel, and the front end is each hold | maintained by the main body housing 24 by press-fitting in the main body housing 24 comprised with the aluminum alloy. The main body housing 24 is an aluminum alloy drawn material or extruded material. The end housing 22 and the front housing 26 are each formed by resin molding.

  In this embodiment, the main body housing 24 is the “housing” in the present invention, the end housing 22 is the “bearing holding member, cover member” in the present invention, and the bearing fitting portion 118 is the “temporary holding portion, radial support portion in the present invention. , “Recesses” respectively.

(Example of application to a liftable toilet seat device)
Next, an example in which the linear actuator device 10 having the above configuration is applied to an elevating toilet seat device 80 will be described with reference to FIGS. 13 and 14.

  The elevating toilet seat device 80 according to the present embodiment is preferably used for, for example, a western-style toilet 82 and includes an elevating mechanism 84. The linear actuator device 10 described above is used as a driving device for operating the lifting mechanism 84 to raise and lower the toilet seat 86 as a driven member.

  The elevating toilet seat device 80 is provided with a main body base member 88 extending from one side to the other side. The main body base member 88 is fixed to the toilet 82, and fixed leg portions 90L and 90R which are respectively hung from the left and right ends of the main body base member 88 and are located on the outer side in the left and right direction of the toilet bowl 82 are linear. Fixed-side connection portions 44 provided on the linear actuators 12L and 12R of the actuator device 10 are connected so as to be rotatable around an axis along the left-right direction. In this embodiment, the forward and backward movement directions of the output rods 20 in the linear actuators 12L and 12R connected and fixed to the fixed-side connection portion 44 are the same.

  Further, in the liftable toilet seat device 80 of the present embodiment, the mounting table 92 is moved up and down by the operation of the mounting table 92 on which the toilet seat 86 is mounted and the pair of left and right linear actuators 12L and 12R provided in the linear actuator device 10. A pair of left and right link mechanism portions 94L and 94R are provided. The link mechanism portions 94L and 94R include first link members 96L and 96R and second link members 98L and 98R, respectively. In addition, leg plate portions 100L and 100R that are located on the outer sides in the left-right direction of the toilet 82 are suspended from the left and right ends of the mounting table 92, respectively. The leg plate portions 100L, 100R overlap the rear upper portions with the fixed leg portions 90L, 90R in a side view.

  In the link mechanism portion 94L provided on the left side surface of the toilet seat 86, the first link member 96L is connected to the movable side connection portion 23 of the output rod 20 of the linear actuator 12L so as to be rotatable around an axis along the left-right direction. At the same time, it is connected to the fixed leg portion 90L of the main body base member 88 and the leg plate portion 100L of the mounting table 92 so as to be rotatable about an axis along the left-right direction. Further, the second link 98L is connected at both ends in the longitudinal direction thereof to the fixed leg portion 90L of the main body base member 88 and the leg plate portion 100L of the mounting table 92 so as to be rotatable about an axis along the left-right direction.

  Similarly, in the link mechanism portion 94R provided on the right side surface of the toilet seat 86, the first link member 96R is connected to the output rod 20 of the linear actuator 12R so as to be rotatable about an axis along the left-right direction, and the main body. The base member 88 is connected to the fixed leg portion 90R and the leg plate portion 100R of the mounting table 92 so as to be rotatable around an axis along the left-right direction. Further, the second link 98R is connected at both ends in the longitudinal direction to the fixed leg portion 90R of the main body base member 88 and the leg plate portion 100R of the mounting base 92 so as to be rotatable around an axis along the left-right direction.

  Although not shown, the hand switch 70A is attached to one of the leg plate portions 100L and 100R (the portion that moves up and down together with the toilet seat 86), and the foot switch 70B is arranged on the floor on which the toilet 82 is installed. It is installed.

  In the liftable toilet seat device 80 configured as described above, when the hand switch 70A or the foot switch 70B is operated in the upward direction, the control circuit board 66 connects the output rods 20 of the linear actuators 12L and 12R to the housing cases 40L and 40R. The power is supplied to each drive motor 16 so as to be simultaneously slid in the advancing direction (in the direction of the arrow X1) (the drive motor 16 is rotated forward).

  In the liftable toilet seat device 80, when the left and right output rods 20 are simultaneously slid in the arrow X1 direction, the first link members 96L and 96R and the second link members 98L and 98R of the link mechanism portions 94L and 94R are in the R1 and R2 directions. Accordingly, as shown by an imaginary line in FIG. 14, the toilet seat 86 is raised together with the mounting table 92. At this time, the linear actuators 12 </ b> L and 12 </ b> R are configured to rotate around the connection point of the fixed side connection portion 44 so as to incline forward as a whole.

  Furthermore, when the control circuit board 66 detects a full advance position detection signal from any of the left and right full advance position detection switches 50, the control circuit board 66 rotates the drive motors 16 of the pair of drive mechanisms 14L and 14R to the full advance side. Is configured to stop.

  On the other hand, in the liftable toilet seat device 80, when the hand switch 70A or the foot switch 70B is operated in the descending direction, the control circuit board 66 stores the left and right output rods 20 in the housing cases 40L and 40R (in the direction of arrow X2). ) Are simultaneously fed to each drive motor 16 (reverse rotation of each drive motor 16). Further, in the elevating toilet seat device 80, when the output rods 20 are simultaneously slid in the direction of the arrow X2, the toilet seat 86 is lowered by an operation opposite to the upward rising.

  In this lowering operation, the control circuit board 66 rotates each drive motor 16 to the full storage side until the full storage position detection signal is detected by the signal from the corresponding full storage position detection switch 52. It has become. That is, the control circuit board 66 simultaneously stops power supply to each drive motor 16 at the end of the raising operation of the toilet seat 86, and supplies power to each drive motor 16 at the end of the lowering operation. Based on the signal from 52, it is comprised so that it may stop independently.

  Further, in the liftable toilet seat device 80, the rotation / linear motion conversion mechanism 18 of the linear actuator device 10, and the worm gear including the worm 33 and the worm wheel 34 are both set to cause self-locking. Inconveniences such as the toilet seat 86 moving up and down due to the load associated with this are prevented. Further, by using a worm gear that is a staggered shaft gear, even when an axial load is input from the output rod 20 to the feed screw shaft 36 via the nut 38, the load acts in the axial direction of the drive motor 16. And the rotation of the worm 33 and the drive motor 16 can be maintained smoothly even while a load in the axial direction is applied to the output rod 20. Further, the rotational speed detector (pulse) of the drive motor 16 can be accurately detected by the rotational speed detector 17 disposed on the drive motor 16 side.

  As described above, the linear actuator device 10 applied to the elevating toilet seat device 80 has the linear actuators 12R and 12L accommodated in the housing cases 40R and 40L, so that the drive units 14R and 14L, High humidity air contact is prevented.

  Next, operations and effects of the liftable toilet seat device 80 and the linear actuator device 10 having the above-described configuration will be described.

  In the elevating toilet seat device 80 according to the present embodiment, when the user or an assistant operates the hand switch 70A or the foot switch 70B to the ascending side, the pair of output rods 20 of the linear actuator device 10 slide simultaneously in the arrow X1 direction. The toilet seat 86 rises. When the hand switch 70A or the foot switch 70B is operated to the lowering side while the user is seated on the toilet seat 86, the pair of output rods 20 of the linear actuator device 10 are simultaneously slid in the arrow X2 direction, and the toilet seat 86 is seated. Descent while supporting the user in the state.

  Further, when the hand switch 70A or the foot switch 70B is operated to the ascending side in the seated state of the user, the pair of output rods 20 of the linear actuator device 10 slide simultaneously in the arrow X1 direction, and the toilet seat 86 is used in the seated state. Rise while supporting the person. When the hand switch 70A or the foot switch 70B is operated to the lowering side after the user leaves the toilet seat 86, the pair of output rods 20 of the linear actuator device 10 slide simultaneously in the arrow X2 direction, and the toilet seat 86 is lowered. To return to the initial position.

  As described above, in the liftable toilet seat device 80 to which the linear actuator device 10 according to the embodiment of the present invention is applied, the user's seating operation on the toilet seat 86 and the standing operation from the toilet seat 86 are assisted, and these operations are easy. become.

  Here, in each of the linear actuators 12 </ b> L and 12 </ b> R of the linear actuator device 10, the bearing 42 is sandwiched and held between the plurality of holding pins 125 and the end housing 22 provided to protrude from the rear opening end 24 </ b> D of the main body housing 24. Therefore, the bearing 42 can be supported (held) with respect to the main body housing 24 with a simple structure. Further, since the end housing 22 is not a structure that restricts the movement of the bearing 42 in the thrust direction alone, it is not necessary to have a structure that bisects the feed screw shaft 36 in the radial direction, and the strength can be ensured. . For this reason, the structure which provides the stationary side connection part 44 which has sufficient intensity | strength in the end housing 22 was realizable.

  In particular, in each of the linear actuators 12L and 12R, a worm wheel 34 for driving the feed screw shaft 36 is disposed between the rear opening end 24D of the main body housing 24 and the bearing 42. A configuration in which the bearing 42 is held without interfering with the worm wheel 34 and the worm 33 meshing with the worm wheel 34 is realized by partially protruding the holding pin 125 from the side opening end 24D in the circumferential direction. In this embodiment, the engaging portion becomes relatively wide by using the worm 33 and the worm wheel 34. However, by using the holding pin 125 having a small diameter as the holding convex portion, the plurality of holding pins 125 are 180 °. It was possible to arrange them at intervals less than. Thereby, the bearing 42 can be stably held.

  Here, in the linear actuators 12R and 12L, since the holding pin 125 is embedded in the rear opening end 24D of the main body housing 24 and held by the main body housing 24, the structure is simple. And since it is not necessary to form the "holding convex part" which the holding pin 125 comprises integrally with the main body housing 24, this main body housing 24 can be obtained cheaply and easily by extrusion molding or pultrusion molding. In addition, since the holding pin 125 is embedded in the main body housing 24 by the pressurized milk, the attaching operation of the holding pin 125 is easy as compared with a configuration using, for example, screwing or bonding.

  Further, in the linear actuators 12R and 12L, the end housing 22 that closes the rear opening end of the main body housing 24 functions as a bearing holding member that holds the bearing 42. Therefore, the structure is further increased without increasing the number of parts. It will be easy. Moreover, as described above, the end housing 22 in which the bearing 42 is sandwiched between the holding pins 125 can be configured as one part (one piece), and the structure is much simpler and the required strength can be easily secured (the design can be improved). Easy).

  Further, since it is not necessary for the end housing 22 itself to have a restricting portion for restricting the forward movement of the bearing 42, the bearing 42 and the worm wheel 34 can be disposed close to each other, so that the apparatus becomes compact as a whole. .

  Furthermore, in the linear actuators 12R and 12L, the end housing 22 is assembled to the main body housing 24 along the axial direction of the feed screw shaft 36 in a state where the bearing 42 is fitted into the bearing fitting portion 118 of the end housing 22, that is, temporarily held. Since the bearing 42 can be held between each holding pin 125 and the annular wall portion of the end housing 22 by the operation, the assembly of the drive portions 14R and 14L is easy. In particular, since each component can be assembled by moving the feed screw shaft 36 in the axial direction, the assembly process (system) by automatic assembly can be simplified.

  Moreover, the portion of the end housing 22 that drives and holds the bearing 42, that is, the bearing insertion portion 118 is a radial support portion that supports the bearing 118 in the radial direction, and thus the structure of the end housing 22 is simple. Further, since the outer ring 42B of the bearing has a circular shape whose outer edge is coaxial with the feed screw shaft 36, and is fitted into the bearing fitting portion 118 having a shape corresponding thereto, the directionality in the circumferential direction at the time of fitting is a problem. Therefore, the assembling work is easier.

  The linear actuators 12R and 12L include a rolling bearing having an inner ring 42A and an outer ring 42B as the bearing 42. The inner ring 42A is fitted to the rear end 36A of the feed screw shaft 36, and the outer ring 42B is an annular wall portion. Since the structure is sandwiched between 118B and the holding pin 125, the radial and thrust play of the bearing 42 is reduced.

  As described above, the linear actuators 12R and 12L constituting the linear actuator device 10 according to the present embodiment can hold the bearing 42 with a simple structure while ensuring the strength of the end housing 22.

  In the above embodiment, the linear actuators 12R and 12L that convert the rotation of the drive motor 16 into the linear motion of the output rod 20 by the feed screw mechanism are exemplified, but the present invention is not limited to this, and for example, a ball screw mechanism Alternatively, the rotation of the drive motor 16 may be converted into the linear motion of the output rod 20 by a rack and pinion mechanism or the like.

  Further, the present invention is not limited to the configuration including the two linear actuators 12R and 12L, and it goes without saying that the present invention may be applied to the linear actuator 12R that functions alone.

  Furthermore, the application of the linear actuator 12R and the like according to the present invention is not limited to the liftable toilet seat device 80, and can be used for various applications.

It is the perspective view which notched part of the rear part of the drive part which comprises the linear actuator apparatus which concerns on embodiment of this invention. It is a disassembled perspective view of the rear part of the drive part which comprises the linear actuator apparatus which concerns on embodiment of this invention. It is the sectional side view which notched the rear part of the drive part which comprises the linear actuator apparatus which concerns on embodiment of this invention. It is a rear view of the main body housing which comprises the linear actuator apparatus which concerns on embodiment of this invention. It is a perspective view which shows the assembly process of the rear part of the drive part which comprises the linear actuator apparatus which concerns on embodiment of this invention. It is a perspective view which shows the assembly process of the front part of the drive part which comprises the linear actuator apparatus which concerns on embodiment of this invention. It is the perspective view which notched some front parts of the drive part which constitutes the linear actuator device concerning the embodiment of the present invention. (A) is a schematic diagram showing a relationship with the swing arm when the abutting portion of the nut moves forward, and (B) is a schematic diagram showing a relationship with the swing arm when the abutting portion of the nut moves backward. FIGS. 9C and 9D are schematic views corresponding to FIGS. 8A and 8B in a comparative example that does not include a cover material. It is a perspective view showing composition of a linear actuator device concerning an embodiment of the present invention. It is a perspective view which shows the internal structure of the linear actuator apparatus which concerns on embodiment of this invention. It is a disassembled perspective view which shows the structure of the drive part of the linear actuator which concerns on embodiment of this invention. It is a figure which shows the wiring connection of the linear actuator apparatus which concerns on embodiment of this invention. It is a figure which shows the state which mounted | wore the toilet bowl with the raising / lowering toilet seat apparatus which concerns on embodiment of this invention, Comprising: (a) is a front view, (b) is a side view. It is a figure which shows a mode that the toilet seat of a toilet bowl raises / lowers with the raising / lowering toilet seat apparatus which concerns on embodiment of this invention, Comprising: (a) is a front view, (b) is a side view.

Explanation of symbols

12L, 12R ... Linear actuator, 20 ... Output rod (output member), 22 ... End housing (bearing holding member, cover member), 24 ... Body housing (housing), 33 ... Worm (Drive side gear), 34 ... worm wheel (driven side external gear), 36 ... feed screw shaft (rotary shaft), 38 ... nut (output member), 42 ... bearing (bearing member) ), 42A... Inner ring, 42B... Outer ring, 118... Bearing insertion part (temporary holding part, radial support part, concave part)

Claims (11)

A rotating shaft that linearly moves the output member by rotating around the axis;
A housing into which the rotating shaft is inserted;
A bearing member for rotatably supporting an axial end portion protruding from the opening end of the housing in the rotating shaft;
A bearing holding member fixed to the outside in the axial direction of the opening end of the housing;
A plurality of holding projections provided protruding from the opening end of the housing, and sandwiching the bearing member with the bearing holding member;
Linear actuator with   The linear actuator according to claim 1, wherein the holding convex portion is configured by embedding a longitudinal end portion of a pin-shaped member in an opening end of the housing.   The linear actuator according to claim 2, wherein the pin-shaped member is embedded in the opening end of the housing by press fitting.   4. The linear actuator according to claim 1, wherein the bearing holding member is a cover member that accommodates the bearing member and closes an opening end of the housing. 5. A driven-side external tooth having a diameter larger than that of the rotating shaft and provided coaxially with the rotating shaft between the open end of the housing and the bearing member and transmitting a rotational force to the rotating shaft Gears,
A drive-side gear meshed with the driven-side external gear;
3. The plurality of holding convex portions are provided in three or more, and are disposed radially outside the driven-side external gear, avoiding an installation position of the driving-side gear, and arranged at an interval of less than 180 °. The linear actuator according to claim 3.   The linear actuator according to claim 5, wherein the driven-side external gear is a worm wheel, and the drive-side gear is a worm.   The linear actuator according to claim 5, wherein the bearing holding member is a cover member that houses the bearing member, the driven-side external gear, and the driving-side gear and that closes the opening end of the housing. The cover member has a temporary holding portion that temporarily holds the bearing member;
The linear actuator according to claim 4 or 7, wherein the bearing member is sandwiched between the cover member and the holding convex portion by an operation of assembling the cover member to the housing.   The linear actuator according to claim 8, wherein the temporary holding portion is a radial support portion that restricts radial movement of the bearing member in the cover member. The bearing member has a circular outer periphery whose outer edge is coaxial with the rotating shaft when viewed from the axial direction of the rotating shaft.
The linear actuator according to claim 9, wherein the radial support portion of the cover member is a recess into which the bearing member is fitted.   The bearing member includes an inner ring and an outer ring which are coaxially rotatable relative to each other. The inner ring is fitted to the rotation shaft, and the outer ring is formed between the bearing holding member and the holding projection. The linear actuator according to claim 1, wherein the linear actuator is sandwiched between the linear actuators.

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