WO2020195648A1

WO2020195648A1 - Opening/closing member driving device

Info

Publication number: WO2020195648A1
Application number: PCT/JP2020/009182
Authority: WO
Inventors: 昭夫石水
Original assignee: 日本電産サンキョー株式会社
Priority date: 2019-03-28
Filing date: 2020-03-04
Publication date: 2020-10-01
Also published as: CN111750056B; JP7320367B2; JP2020162695A; CN111750056A

Abstract

The present invention provides an opening/closing member driving device in which an assist spring that biases an output shaft is doubly disposed, wherein interference between an inner spring and an outer spring is avoided.　An opening/closing member driving device 1 comprises: an output shaft 2 protruding from a case 10; a motor 3, which is a driving source; a transmission mechanism 4 that transmits rotation of the motor 3 to the output shaft 2; and an assist spring 5 that biases the output shaft 2. The assist spring 5 is provided with a first spring 51, and a second spring 52 disposed at an inner circumferential side of the first spring 51. The case 10 is provided with an intermediate plate 161 that partitions an internal space, and a support part 6 and a rib 7 that protrude from the intermediate plate 161 towards the output shaft 2 side. The support part 6 rotatably supports the output shaft 2 and is disposed at an inner circumferential side of the second spring 52. The rib 7 is disposed between the first spring 51 and the second spring 52.

Description

Opening and closing member drive device

The present invention relates to an opening / closing member driving device including an output shaft to which an opening / closing member is connected, a drive source for driving the output shaft, and a case for accommodating the drive source.

As an opening / closing member driving device for opening / closing an opening / closing member such as a toilet seat or a toilet lid of a Western-style toilet, a device that transmits the rotation of a drive source such as a motor to an output shaft via a transmission mechanism such as a train wheel is used. Patent Document 1 discloses this type of opening / closing member driving device (lid opening / closing device). The lid opening / closing device of Patent Document 1 incorporates an assist spring that urges the output shaft to assist the opening / closing of the opening / closing member. Further, a torque limiter is incorporated in order to prevent the motor and the transmission mechanism from being damaged due to an excessive load when the opening / closing member is suddenly opened / closed.

Japanese Unexamined Patent Publication No. 2014-400858

In the lid opening / closing device of Patent Document 1, a motor and a reduction wheel train are housed in a case. The output shaft includes a gear portion that meshes with the final gear of the reduction wheel train and a shaft portion that extends in the axial direction from the center of the gear portion, and the tip of the shaft portion projects to the outside of the case. The assist spring is arranged on the outer peripheral side of the shaft portion. One end of the assist spring is locked in a fixing hole provided on the end face of the gear portion. The other end of the assist spring is locked to a locking portion provided on the inner wall of the case.

In an opening / closing member drive device equipped with an assist spring, it has been proposed to combine a plurality of assist springs in order to increase the assist force and freely set the assist force. For example, it has been proposed to double-arrange a plurality of assist springs. However, if the assist springs are arranged twice, when the output shaft rotates and the assist springs bend, the assist springs may be deformed in an unexpected direction and interfere with each other. If the assist springs interfere with each other, the spring operation cannot be performed normally, and the spring force as designed may not be obtained. In addition, abnormal stress may be generated, which may impair durability.

In view of the above problems, an object of the present invention is to avoid interference between the inner spring and the outer spring in the opening / closing member drive device in which the assist spring for urging the output shaft is doubly arranged. ..

In order to solve the above problems, the opening / closing member driving device of the present invention includes a case, an output shaft protruding from the case, a motor housed in the case, and the rotation of the motor housed in the case. With the transmission mechanism transmitted to the output shaft and the rotation of the output shaft in the first rotation direction, an assist force for urging the output shaft in the second rotation direction opposite to the first rotation direction is generated. The assist spring includes an assist spring, the assist spring includes a first spring, and a second spring arranged on the inner peripheral side of the first spring, and the first spring and the second spring are torsion coils. The case is a spring, and the case includes an intermediate plate that partitions an internal space, and a support portion and a rib that protrude from the intermediate plate toward the output shaft, and the support portion rotatably supports the output shaft. The support portion is arranged on the inner peripheral side of the second spring, and the rib is arranged between the first spring and the second spring.

According to the present invention, as an assist spring for urging the output shaft, a first spring and a second spring arranged on the inner peripheral side of the first spring are provided, and two twists arranged twice. It is equipped with a coil spring. The case is provided with an intermediate plate that partitions the inside, from which the support portion arranged on the inner peripheral side of the assist spring protrudes, and further, the rib arranged between the first spring and the second spring protrudes. ing. By arranging the ribs of the case between the first spring and the second spring in this way, it is possible to prevent the first spring and the second spring from interfering with each other. As a result, it is possible to reduce the possibility that the first spring and the second spring interfere with each other to perform normal spring operation, and the spring force as designed cannot be obtained. Further, it is possible to reduce the possibility that an abnormal stress is generated due to the interference between the first spring and the second spring and the durability is impaired.

In the present invention, it is preferable that at least a part of the outer peripheral edge of the rib has a shape along the inner circumference of the first winding of the first spring. In this way, the first spring can be guided from the inner peripheral side by the rib. Therefore, the position accuracy of the first spring can be improved. Further, since the deformation of the first spring can be suppressed, the interference between the first spring and the second spring can be suppressed.

In the present invention, it is preferable that a radial gap is provided between the rib and the first winding of the first spring. By providing a certain amount of gap between the rib and the first spring in this way, it is possible to suppress the contact between the first spring and the rib when the first spring is deformed by the rotation of the output shaft. Therefore, it is possible to suppress a decrease in durability due to contact between the first spring and the rib.

In the present invention, it is preferable that the rib is provided with a protruding portion that protrudes outward in the radial direction of the first spring. By providing the protruding portion, the rotation of the first spring can be regulated by the protruding portion. Therefore, the rotation of the first spring can be stopped.

In the present invention, it is preferable that the intermediate plate includes an opening in which the end of the first spring is arranged, and the protruding portion projects toward the opening. In this way, the protruding portion functions as a guide portion for extending the spring end portion toward the opening portion. Therefore, the position accuracy of the first spring can be improved. Moreover, the assembly work of the first spring is easy.

In the present invention, the protruding portion is a receiving portion that supports a part of the first spring. In this way, for example, the intermediate plate can support the winding start portion of the first roll, and the receiving portion can support the winding end portion of the first roll. Therefore, since the inclination of the first spring can be suppressed, interference between the first spring and the second spring can be suppressed.

In the present invention, the height of the rib is preferably lower than the wire diameter of the first spring. By doing so, it is possible to prevent the first spring from floating from the intermediate plate. Therefore, since the first spring can be supported in a stable state by the intermediate plate, the inclination of the first spring can be suppressed.

In the present invention, it is preferable that the rib has a tapered shape in which the width in the radial direction becomes narrower as the distance from the protruding portion in the circumferential direction increases. In this way, the radial gap between the first spring and the second spring and the rib can be increased as the distance from the protrusion in the circumferential direction increases. Therefore, it is possible to provide a certain amount of gap between the rib and the portion other than the end portion of the first spring while improving the positional accuracy of the end portion of the first spring arranged in the opening. Therefore, when the first spring is deformed by the rotation of the output shaft, the contact between the first spring and the rib can be suppressed, and the decrease in durability due to the contact between the first spring and the rib can be suppressed.

In the present invention, the inner peripheral edge of the rib preferably has a shape along the outer peripheral edge of the second spring. In this way, the second spring can be guided from the outer peripheral side by the rib. Therefore, the position accuracy of the second spring can be improved. Further, since the deformation of the second spring can be suppressed, the interference between the first spring and the second spring can be suppressed.

In the present invention, the support portion includes a groove portion extending in the radial direction, the end portion of the second spring is arranged in the groove portion, and the groove portion is radially outward from the radial center of the support portion. It is preferable that the groove width is increased. In this way, the end portion of the second spring can be tilted in the circumferential direction in the groove portion. Therefore, when the output shaft rotates, it is possible to prevent the urging force of the second spring from being generated from the reference position to a predetermined angle.

In the present invention, the rib preferably has a symmetrical shape with respect to a straight line connecting the opening and the radial center of the support. In this way, the first spring can be attached even if the winding direction is reversed. Therefore, since the first spring in the winding direction corresponding to the rotation direction of the output shaft can be attached, it is not necessary to change the shape of the rib depending on the rotation direction of the output shaft, and it is not necessary to change the shape of the case. Therefore, the parts can be shared.

It is an external perspective view of the opening / closing member drive device to which this invention is applied. It is explanatory drawing of the Western-style toilet bowl provided with the opening / closing member driving device 1 of FIG. It is sectional drawing of the opening / closing member drive device of FIG. It is an exploded perspective view of the opening / closing member drive device of FIG. It is a perspective view which looked at the motor, the driving force transmission mechanism and the output shaft from the other side of the 1st direction. It is an exploded perspective view of an output gear and an output shaft. It is an exploded perspective view of an output gear, an output shaft, and an assist spring. It is a perspective view which looked at the 1st case and the intermediate case from the other side of the 1st direction. It is explanatory drawing which shows the planar shape of a support part, a rib, and an assist spring. It is explanatory drawing which shows the state of the assist spring when the output shaft is in a reference position. It is explanatory drawing which shows the state of the assist spring when the output shaft is in the action start position of the 2nd spring. It is explanatory drawing which shows the state of the assist spring when the output shaft is in the action start position of the 1st spring.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is an external perspective view of an opening / closing member driving device 1 to which the present invention is applied. FIG. 2 is an explanatory view of a Western-style toilet bowl 100 provided with the opening / closing member driving device 1 of FIG. FIG. 3 is a cross-sectional view of the opening / closing member driving device 1 of FIG. FIG. 4 is an exploded perspective view of the opening / closing member driving device 1 of FIG. FIG. 5 is a perspective view of the motor 3, the transmission mechanism 4, and the output shaft 2 as viewed from the other side Z2 of the first direction Z.

In the present specification, the three directions orthogonal to each other are referred to as the first direction Z, the second direction Y, and the third direction X. The first direction Z is the direction of the axis L of the output shaft 2, the second direction Y is the longitudinal direction of the case 10, and the third direction X is the lateral direction (width direction) of the case 10. Further, one side of the first direction Z is Z1, the other side is Z2, one side of the second direction Y is Y1, the other side is Y2, one side of the third direction X is X1, and the other side is X2. .. The side where the output shaft 2 protrudes from the case 10 is the other side Z2 of the first direction Z, and the side where the output shaft 2 is arranged in the case 10 is the one side Y1 of the second direction Y.

(overall structure)
The opening / closing member driving device 1 shown in FIG. 1 is a device that opens / closes by rotating an opening / closing member such as a lid or a door. The Western-style toilet bowl 100 shown in FIG. 2 has a toilet bowl body 110, a toilet seat 120, a toilet lid 130, and a tank 140. The toilet seat 120 and the toilet lid 130 are respectively connected to the output shaft 2 (see FIG. 3) of the opening / closing member driving device 1. The toilet seat 120 and the toilet lid 130 are displaced by the rotation of the output shaft 2 into a closed posture that covers the toilet body 110 and an open posture that rises from the toilet body 110. The Western-style toilet bowl 100 may be configured such that only one of the toilet seat 120 and the toilet lid 130 is rotated by the opening / closing member driving device 1.

As shown in FIG. 3, the opening / closing member driving device 1 includes a motor 3, an output shaft 2, a transmission mechanism 4 that transmits the driving force of the motor 3 to the output shaft 2, and an assist spring 5 that urges the output shaft 2. And a case 10 for accommodating the motor 3 and the transmission mechanism 4. The output shaft 2 includes a base 21 housed in the case 10 and a connecting shaft 22 protruding from the opening 9 of the case 10. An opening / closing member such as a toilet seat 120 and a toilet lid 130 shown in FIG. 2 is connected to the connecting shaft 22. As shown in FIG. 1, the case 10 has an elongated shape in the second direction Y when viewed from the first direction Z, which is the axial direction of the output shaft 2. The opening 9 of the case 10 in which the output shaft 2 is arranged is located at one end of the second direction Y, which is the longitudinal direction of the case 10.

Case 10 is made of resin. As shown in FIG. 1, the case 10 includes a first side wall 11 and a second side wall 12 extending parallel to the second direction Y. Further, the case 10 has a third side wall 13 connecting the ends of the other side Y2 of the first side wall 11 and the second side wall 12 in the second direction Y, and a second side wall Y of the first side wall 11 and the second side wall 12. A fourth side wall 14 connecting the ends of Y1 on one side is provided. The third side wall 13 extends linearly in the third direction X. The fourth side wall 14 has a convex shape protruding toward one side Y1 of the second direction Y. In this embodiment, the fourth side wall 14 is a semicircular curved surface when viewed from the other side Z2 of the first direction Z.

As shown in FIGS. 1 and 3, the case 10 includes a first case 15, an intermediate case 16, and a second case 17 arranged along the first direction Z. The first case 15 is located on one side Z1 of the first direction Z of the intermediate case 16, and the second case 17 is located on the other side Z2 of the first direction Z of the intermediate case 16. The case 10 is assembled by fixing the intermediate case 16 to the first case 15 and fixing the second case 17 to the intermediate case 16.

The first case 15 includes a bottom plate 151 and a frame portion 152 extending from the outer peripheral edge of the bottom plate 151 to the other side Z2 in the first direction Z. The frame portion 152 constitutes an end portion of one side Z1 of the first side wall 11, the second side wall 12, the third side wall 13, and the fourth side wall 14 of the case 10. The motor 3 is fixed to the first case 15. The motor 3 includes a motor main body 30 and a rotating shaft 31 protruding from the motor main body 30. The rotation shaft 31 faces in a direction intersecting the axis L of the output shaft 2. In this example, the rotation center line L1 of the rotation axis 31 (see FIG. 4) is orthogonal to the axis line L of the output axis 2. Further, the rotation shaft 31 is inclined with respect to the second direction Y (longitudinal direction of the case 10) when viewed from the first direction Z. The tip of the rotating shaft 31 is rotatably supported by a bearing member 32 held in the first case 15.

The intermediate case 16 includes an intermediate plate 161 and an intermediate frame portion 162 extending from the outer peripheral edge of the intermediate plate 161 to the other side Z2 in the first direction Z. The intermediate frame portion 162 constitutes an intermediate portion in the first direction Z of the first side wall 11, the second side wall 12, the third side wall 13, and the fourth side wall 14 of the case 10. The intermediate case 16 accommodates a part of the gears constituting the transmission mechanism 4. Further, the intermediate case 16 accommodates the base 21 of the output shaft 2.

A plate-shaped reinforcing member 18 is fixed to the end portion of the intermediate case 16 on the side of the second case 17. The reinforcing member 18 has a higher rigidity than the case 10. In this example, the reinforcing member 18 is made of metal. The reinforcing member 18 is provided with a reinforcing member side opening 181, and the output shaft 2 projects from the reinforcing member side opening 181 to the other side Z2 in the first direction Z. Further, a potentiometer 8 is attached to the reinforcing member 18. The potentiometer 8 is arranged at the end portion of the second direction Y on the side opposite to the output shaft 2 (the other side Y2 of the second direction Y).

The potentiometer 8 includes a potentiometer 81 (see FIG. 5) that meshes with one of a plurality of gears constituting the transmission mechanism 4, and a detection unit 82 (FIG. 3, FIG. 3) that detects the rotational angle position of the potentiometer 81. (See FIG. 4). The detection unit 82 includes a circuit board. The potentiometer 81 is located on one side Z1 of the first direction Z of the reinforcing member 18 and meshes with the third small diameter gear of the third gear. The detection unit 82 is located on the other side Z2 of the reinforcing member 18, and the circuit board is fixed to the reinforcing member 18.

The second case 17 has a plate shape and is covered from the other side Z2 of the first direction Z to the intermediate case 16. The second case 17 is connected to the end portion of the first side wall 11, the second side wall 12, the third side wall 13, and the fourth side wall 14 of the case 10 on the other side Z2 of the first direction Z, and is connected to the end portion of the first side wall Z of the first direction Z. The reinforcing member 18 is covered from the other side Z2. The second case 17 includes an opening 9 that penetrates a portion that overlaps with the reinforcing member side opening 181 when viewed from the first direction Z. As shown in FIG. 3, the gap between the output shaft 2 arranged in the opening 9 and the inner peripheral surface of the opening 9 is sealed by the O-ring 19.

As shown in FIG. 5, the transmission mechanism 4 has a worm 40, a first gear 41, a second gear 42, a third gear 43, a fourth gear 44, and the like from the upstream side to the downstream side of the driving force transmission path. The output gear 45 is provided. The worm 40 is fixed to the outer peripheral side of the rotating shaft 31 of the motor 3. As shown in FIG. 4, the worm 40 and the first gear 41 are arranged in the first case 15. As shown in FIG. 3, the second gear 42, the third gear 43, the fourth gear 44, and the output gear 45 are arranged in the intermediate case 16.

The first gear 41 includes a first large-diameter gear 411 that meshes with the worm 40, and a first small-diameter gear 412 that is coaxial with the first large-diameter gear 411 and has an outer diameter smaller than that of the first large-diameter gear 411. The first large-diameter gear 411 is located on one side Z1 of the first small-diameter gear 412 in the first direction Z. The first gear 41 is rotatably supported by a first support shaft 413 (see FIG. 4) extending in the first direction Z. One end portion of the first support shaft 413 is held by the bottom plate 151 of the first case 15, and the other end portion is held by the intermediate plate 161 of the intermediate case 16. The first gear 41 includes a torque limiter 46 that connects and disconnects the transmission of the driving force between the first large-diameter gear 411 and the first small-diameter gear 412.

The second gear 42 includes a second large-diameter gear 421 that meshes with the first small-diameter gear 412 and a second small-diameter gear 422 that is coaxial with the second large-diameter gear 421 and has an outer diameter smaller than that of the second large-diameter gear 421. It is a compound gear provided. The second large-diameter gear 421 is located on one side Z1 of the first direction Z of the second small-diameter gear 422. The second large-diameter gear 421 meshes with the first small-diameter gear 412 via an opening 163 (see FIG. 8) provided in the intermediate plate 161 of the intermediate case 16. The second gear 42 is rotatably supported by a second support shaft 423 (see FIG. 5) extending in the first direction Z.

The third gear 43 includes a third large-diameter gear 431 that meshes with the second small-diameter gear 422 and a third small-diameter gear 432 that is coaxial with the third large-diameter gear 431 and has an outer diameter smaller than that of the third large-diameter gear 431. It is a compound gear provided. The third large-diameter gear 431 is located on one side Z1 of the first direction Z of the third small-diameter gear 432. The third gear 43 is rotatably supported by a third support shaft 433 extending in the first direction Z. One end portion of the third support shaft 433 is held by the intermediate plate 161 of the intermediate case 16, and the other end portion is held by the second case 17 through the reinforcing member 18.

The fourth gear 44 is a spur gear that meshes with the third small diameter gear 432 and the output gear 45. The fourth gear 44 and the output gear 45 are arranged in the second direction Y. The fourth gear 44 is arranged coaxially with the second gear 42 and is rotatably supported by the second support shaft 423. One end portion of the second support shaft 423 is held by the intermediate case 16, and the other end portion is held by the reinforcing member 18. That is, the reinforcing member 18 includes a shaft holding portion 182 (see FIG. 3) that holds the second support shaft 423 that supports the second gear 42 and the fourth gear 44.

FIG. 6 is an exploded perspective view of the output gear 45 and the output shaft 2. The output gear 45 is made of metal. A resin output shaft 2 is coaxially fixed to the output gear 45. The output gear 45 is an annular member provided with a center hole 451 that opens in the first direction Z. A plurality of recesses 452 are provided in the circumferential direction on the inner peripheral surface of the center hole 451, and a plurality of convex portions 23 fitted in the recesses 452 on the inner peripheral surface of the output gear 45 are provided on the outer peripheral surface of the base 21 of the output shaft 2. It is provided. Therefore, the output gear 45 and the output shaft 2 are connected around the axis L in a state in which they cannot rotate relative to each other. The base 21 of the output shaft 2 is a resin portion and is fixed to the output gear 45 by thermal caulking.

The output gear 45 is rotatably supported by the reinforcing member 18. The output gear 45 includes an annular portion 450 having no tooth portion on the outer peripheral surface at the end portion of Z2 on the other side of the first direction Z. On the other hand, the reinforcing member 18 includes an output gear receiving portion 183 that rotatably supports the annular portion 450 of the output gear from the outer peripheral side at the outer peripheral edge portion of the reinforcing member side opening 181 (see FIG. 3). The output gear receiving portion 183 is an annular tubular portion that bends and extends to the other side of the reinforcing member side opening 181 in the reinforcing member 18 in the first direction, and is formed by, for example, burring.

FIG. 7 is an exploded perspective view of the output gear 45, the output shaft 2, and the assist spring 5. As shown in FIGS. 3 and 7, the assist spring 5 includes a first spring 51 and a second spring 52. The first spring 51 and the second spring 52 are torsion coil springs. As shown in FIG. 3, the second spring 52 is arranged on the inner peripheral side of the first spring 51. The first spring 51 is located on one side Z1 of the output gear 45 in the first direction Z. Further, the second spring 52 is located on one side Z1 of the first direction Z of the output shaft 2 and is located on the inner peripheral side of the first spring 51.

As shown in FIG. 7, the first spring 51 includes a spring portion 510 in which a wire rod 50A having a rectangular cross section is spirally wound, a first end portion 511 extending from the spring portion 510 to one side Z1 in the first direction Z, and a spring. A second end portion 512 extending from the portion 510 to the other side Z2 in the first direction Z is provided. As shown in FIG. 5, the second end portion 512 of the first spring 51 is arranged in the notch portion 453 notched from the outer peripheral surface of the output gear 45 toward the inner peripheral side. The output gear 45 has teeth formed on the outer peripheral surface of the range excluding the notch 453. The notch 453 includes a first surface 454 provided at one end in the circumferential direction and a second surface 455 provided at the other end in the circumferential direction. As will be described later, when the output shaft 2 rotates to a predetermined angular position, the second end portion 512 comes into contact with the second surface 455. When the output shaft 2 further rotates, the output shaft 2 is urged by the first spring 51 via the output gear 45.

FIG. 8 is a perspective view of the first case 15 and the intermediate case 16 as viewed from the other side Z2 of the first direction Z. As shown in FIGS. 3 and 8, the intermediate case 16 includes a support portion 6 projecting from the intermediate plate 161 to the other side Z2 in the first direction Z. As shown in FIG. 3, the support portion 6 is located on the inner peripheral side of the first spring 51 and the second spring 52, and protrudes from the first spring 51 and the second spring 52 to the other side Z2 in the first direction Z. To do. That is, the first spring 51 and the second spring 52 are held by the support portion 6 and supported by the intermediate plate 161 from one side Z1 of the first direction Z.

In this embodiment, the motor 3 is arranged on one side Z1 of the first direction Z of the intermediate plate 161. The intermediate plate 161 divides the internal space of the case 10 into a lower space in which the motor 3 is arranged and an upper space in which the output shaft 2 and the assist spring 5 and the like are arranged. The motor 3 includes a receiving portion 33 that supports the intermediate plate 161 from one side Z1 of the first direction Z. The receiving portion 33 is a side surface of the motor body 30 on the other side Z2 in the first direction Z, and is composed of, for example, a metal motor case. In this embodiment, since the motor body 30 has a square cross section, the receiving portion 33 is a flat surface perpendicular to the axis L. The receiving portion 33 supports the intermediate plate 161 and also supports the supporting portion 6 from the side opposite to the output shaft 2 in the axis L direction (that is, one side Z1 of the first direction Z).

The output shaft 2 and the output gear 45 are rotatably supported by the tip portion of the support portion 6. The output shaft 2 is provided with a circular recess 24 recessed in the other side Z2 on the end surface of one side Z1 of the first direction Z of the base 21, and the tip portion of the support portion 6 is arranged in the circular recess 24. It is in contact with the bottom surface of the circular recess 24. Here, the tip of the other side Z2 of the support portion 6 in the first direction Z is a position on the inner peripheral side of the output gear receiving portion 183 of the reinforcing member 18 that rotatably supports the annular portion 450 of the output gear 45. Extends to.

As shown in FIG. 8, the intermediate case 16 is provided with an opening 164 that penetrates the intermediate plate 161 in the first direction Z. The opening 164 is an intermediate frame portion 162 of the intermediate case 16 that includes a frame portion 165 and a support portion 6 located on one side X1 of the third direction X among a pair of frame portions extending parallel to the second direction Y. It is provided in between. The opening 164 is provided at a position where the first end portion 511 of the first spring 51 can be arranged when the first spring 51 and the second spring 52 are mounted on the outer peripheral side of the support portion 6. Further, the first case 15 is provided with a spring holding portion 153 at a position overlapping the opening 164 of the intermediate case 16 when viewed from the first direction Z. The spring holding portion 153 includes a spring locking hole 154 that is recessed in one side Z1 of the first direction Z. The first spring 51 is inserted into a spring locking hole 154 provided in the spring holding portion 153 of the first case 15 with the first end portion 511 protruding from the opening 164 of the intermediate case 16 to one side Z1 of the first direction Z. Will be done.

In the first case 15, the spring holding portion 153 is supported by the motor 3 from a direction intersecting the first direction Z, which is the direction in which the spring locking hole 154 opens. That is, the motor 3 includes a spring receiving portion 34 that receives the spring holding portion 153 from a direction intersecting the opening direction (first direction Z) of the spring locking hole 154. As shown in FIG. 8, the spring holding portion 153 projects from the inner surface of the frame portion 152 of the first case 15 to the side where the motor body 30 is located (the other side X2 in the third direction X). The spring holding portion 153 includes an inclined surface 155 cut out at the end of the other side X2 in the third direction X so as to be parallel to the side surface of the motor main body 30. When the motor 3 is housed in the first case 15, the inclined surface 155 of the spring holding portion 153 is supported by the side surface of the motor body 30 from the other side X2 in the third direction X. That is, the spring receiving portion 34 is a side surface of the motor main body 30, and is composed of, for example, a metal motor case.

As shown in FIG. 7, the second spring 52 is bent inward in the radial direction from a spring portion 520 in which a wire rod 50B having a circular cross section is spirally wound and an end portion of one side Z1 of the first direction Z of the spring portion 520. It includes a first end portion 521 extending linearly and a second end portion 522 extending from the spring portion 520 to the other side Z2 in the first direction Z. The first end portion 521 of the second spring 52 is arranged in the groove portion 61 (see FIGS. 8, 9 (b) and 10 (b)) provided in the support portion 6. As a result, the first end portion 521 of the second spring 52 is locked to the intermediate case 16. Further, as shown in FIG. 7, the output shaft 2 includes a spring locking hole 25 provided on the end surface of the other side Z2 of the base portion 21. The second end portion 522 of the second spring 52 is arranged in the spring locking hole 25 of the output shaft 2.

(Rib shape)
As shown in FIG. 8, the intermediate case 16 includes ribs 7 extending in the circumferential direction on the outer peripheral side of the support portion 6. The rib 7 projects from the intermediate plate 161 to the other side Z2 in the first direction Z. When the first spring 51 and the second spring 52 are mounted on the outer peripheral side of the support portion 6, one end of the rib 7 in the circumferential direction is arranged between the first spring 51 and the second spring 52 (see FIG. 3). ). The inner peripheral edge 71 of the rib 7 has an arc shape. That is, the inner peripheral edge 71 of the rib 7 has a shape along the outer peripheral edge of the spring portion 520 of the second spring 52, which is a spring arranged on the inner peripheral side. On the other hand, the outer peripheral edge of the rib 7 is provided with

arc portions

72A and 72B along the inner circumference of the spring portion 510 of the first spring 51 at both ends in the circumferential direction, and protrudes radially outward in the center of the circumferential direction. A protruding portion 73 is provided. The protruding portion 73 has a shape that protrudes inward of the opening 164. Further, the outer peripheral edge of the rib 7 is provided with

straight portions

74A and 74B extending in the tangential direction of the

arc portions

72A and 72B, respectively, on both sides of the tip of the protruding portion 73 in the circumferential direction.

As shown in FIG. 7, the first spring 51 includes a linear portion 513 extending in the tangential direction of the first winding 510A from the winding start position of the first winding 510A of the spring portion 510, and the first end portion 511 , It bends and extends from the tip of the linear portion 513 to one side Z1 of the first direction Z.

FIG. 9 is an explanatory view showing the planar shapes of the support portion 6, the rib 7, and the assist spring 5. The planar shape of the first spring 51 shown in FIG. 9 is the planar shape of the first roll 510A, the linear portion 513, and the first end portion 511. In the rib 7 provided in the intermediate case 16, the arc portion 72A provided at one end in the circumferential direction of the outer peripheral edge extends along the inner circumference of the winding start portion of the first winding 510A of the spring portion 510. ing. Further, the straight portion 74A extending from the arc portion 72A to the tip of the protruding portion 73 extends along the linear portion 513. The first spring 51 is arranged in a state in which the winding start portion and the linear portion 513 of the first winding 510A of the spring portion 510 extend along the outer peripheral edge of the rib 7. As a result, the protrusion 73 of the rib 7 prevents the first spring 51 from rotating, and the linear portion 513 of the first spring 51 is positioned at an angle position extending toward the opening 164.

The rib 7 has a symmetrical shape with respect to a straight line L0 connecting the opening 164 in which the first end portion 511 is arranged and the radial center P of the support portion 6. As shown in FIG. 9, the tip of the protrusion 73 is located on the straight line L0, and the rib 7 extends from the tip of the protrusion 73 to the straight portion 74A extending to one side in the circumferential direction and to the other side in the circumferential direction. A straight portion 74B is provided. Further, the rib 7 includes an arc portion 72A extending to one side in the circumferential direction of the straight portion 74A and an arc portion 72B extending to the other side in the circumferential direction of the straight portion 74B. That is, the straight line portion 74A and the arc portion 72A and the straight line portion 74B and the arc portion 72B have symmetrical shapes with respect to the straight line L0. The rib 7 is provided in an angle range of 180 ° about the straight line L0 as the center in the circumferential direction.

That is, as shown in FIG. 9, the first spring 51 of the present embodiment has a shape in which the linear portion 513 is guided by the linear portion 74A located on one side in the circumferential direction with respect to the tip of the protruding portion 73. When the winding direction of the first spring 51 is reversed, the linear portion 513 is guided by the straight portion 74B located on the other side in the circumferential direction with respect to the tip of the protruding portion 73, and the first spring 51 Can be installed. That is, it is not necessary to change the shape of the rib 7 even when the winding direction of the first spring 51 is reversed.

The protruding height of the rib 7 in the first direction Z is smaller than the wire diameter of the wire rod 50A constituting the first spring 51. In the first spring 51, the winding end portion of the first winding 510A of the spring portion 510 extends in the circumferential direction on one side Z1 of the first direction Z of the protruding portion 73 of the rib 7. Therefore, the protruding portion 73 functions as a receiving portion that supports a part of the first spring 51 from one side Z1 of the first direction Z.

Both ends of the rib 7 in the circumferential direction (the portions where the

arc portions

72A and 72B are provided) have a tapered shape in which the width in the radial direction is not constant and the width in the radial direction becomes narrower as the distance from the protruding portion 73 in the circumferential direction increases. .. Therefore, a radial gap S is formed between the first winding 510A of the first spring 52 and the arc portion 72A of the rib 7.

Further, the inner peripheral edge 71 of the rib 7 is an inclined surface in which the distance from the radial center P of the support portion 6 increases toward the other side Z2 of the first direction Z. Therefore, the second spring 52 is supported by the inner peripheral edge 71 from one side Z1 of the first direction Z.

(motion)
In the opening / closing member driving device 1, when the motor 3 is driven in the forward direction or the reverse direction, the driving force of the motor 3 is transmitted to the output shaft 2 via the transmission mechanism 4, and the output shaft 2 is transferred to the first rotation direction CW or It rotates in the second rotation direction CCW. As a result, the opening / closing members such as the toilet seat and the toilet lid fixed to the output shaft 2 rotate in the opening direction or the closing direction. When the opening / closing member rotates, the potentiometer 8 outputs a signal corresponding to the position of the opening / closing member. Further, when the opening / closing member connected to the output shaft 2 rotates in the first rotation direction CW, the assist spring 5 rotates the output shaft 2 around the axis L in the second rotation direction CCW opposite to the first rotation direction CW. The urging force to be made is applied to the output shaft 2. That is, when driving the opening / closing member, an assist force for urging the output shaft 2 is applied to the output shaft 2. Further, since the transmission mechanism 4 includes the torque limiter 46 on the first gear 41, the torque limiter 46 functions when an excessive load is applied to the transmission mechanism 4 from the opening / closing member via the output shaft 2. The transmission of the driving force transmission by the transmission mechanism 4 is cut off. As a result, it is possible to prevent the transmission mechanism 4 from being damaged due to an excessive load from the outside.

(Working angle range of assist spring)
The assist spring 5 has different working angle ranges (angle ranges for generating urging force) between the first spring 51 and the second spring 52. When the opening / closing member is a toilet seat or a toilet lid, the load curve showing the relationship between the rotational load when rotating the opening / closing member from the reference position by a predetermined angle and the rotation angle from the reference position has a shape showing a simple proportional relationship. Absent. Therefore, by combining a plurality of springs having different working angle ranges, a graph showing the relationship between the total force of the driving force of the motor 3 and the urging force of the first spring 51 and the second spring 52 and the rotation angle is shown as a load curve. Is approaching.

FIG. 10 is an explanatory diagram showing a state of the assist spring 5 when the output shaft 2 is at the reference position R0. FIG. 11 is an explanatory diagram showing a state of the assist spring 5 when the output shaft 2 is at the action start position R2 of the second spring 52. 10 (a) and 11 (a) show the rotation position of the output shaft 2, and FIGS. 10 (b) and 11 (b) show the state of the assist spring 5. FIG. 12 is an explanatory diagram showing a state of the assist spring 5 when the output shaft 2 is at the action start position R1 of the first spring 51.

As shown in FIG. 10A, when the output shaft 2 is at the reference position R0, the second end portion 512 of the first spring 51 is located on one side of the notch portion 453 of the output gear 45 in the circumferential direction. , Away from the second surface 455. Therefore, no urging force is applied from the first spring 51 to the output gear 45. Further, as shown in FIG. 10B, the first end portion 521 of the second spring 52 is located at the center in the circumferential direction of the groove portion 61 provided in the support portion 6. The width of the groove portion 61 in the circumferential direction (groove width) increases from the radial center of the support portion 6 toward the outside in the radial direction, and the first end portion 521 is in the circumferential direction within a range that does not contact the inner surface of the groove portion 61. It is a shape that can be moved. Therefore, no urging force is applied from the second spring 51 to the output shaft 2.

As shown in FIG. 11A, when the output shaft 2 rotates in the first rotation direction CW to the action start position R2 of the second spring 52, the second end portion 512 of the first spring 51 becomes the second surface 455. It approaches, but is still far from the second side 455. Therefore, no urging force is applied from the first spring 51 to the output gear 45. On the other hand, as shown in FIG. 11B, in the second spring 52, the first end portion 521 of the second spring 52 tilts in the groove portion 61 in the first rotation direction CW as the output shaft 2 rotates, and comes into contact with the inner surface of the groove portion 61. are doing. Therefore, when the output shaft 2 further rotates in the first rotation direction CW from here, the second spring 52 is deformed to generate an urging force.

Next, as shown in FIG. 12, when the output shaft 2 further rotates in the first rotation direction CW and reaches the action start position R1 of the first spring 51, the first spring 51 has a second end portion 512. Contact the second surface 455. Therefore, when the output shaft 2 further rotates in the first rotation direction CW from here, the first spring 51 is deformed to generate an urging force. From the above, the assist spring 5 does not generate an assist force from the reference position R0 to the action start position R2 of the second spring 52, and only the second spring 52 has an urging force from the action start position R2 to the action start position R1. Is generated, so that the assist force is generated by only one spring. Then, from the action start position R1, both the second spring 52 and the first spring 51 generate an urging force, so that the total becomes the assist force.

In this embodiment, when the rotation angle of the output shaft 2 at the reference position R0 is 0 ° and the rotation angle of the output shaft 2 at the maximum rotation position is Rmax °, the action angle range of the first spring 51 (first action angle range). ) Is the range from the action start position R1 of the first spring 51 to the maximum rotation position. The action angle range of the second spring 52 (second action angle range) is a range from the action start position R2 of the second spring 52 to the maximum rotation position. For example, when Rmax ° is 120 ° and the rotation angle of the first spring 51 at the action start position R1 is 50 °, the first action angle range is 50 ° to 120 °. Further, when the rotation angle of the second spring 52 at the action start position R2 is 20 °, the second action angle range is 20 ° to 120 °. Therefore, the assist force is not generated until the output shaft 2 rotates 20 ° from the reference position R0, and the urging force of the second spring 52 becomes the assist force when the rotation angle from the reference position R0 is in the range of 20 ° to 50 °. In the range of the rotation angle from the reference position R0 of 50 ° to 120 °, the sum of the urging force of the second spring 52 and the urging force of the first spring 51 is the assist force.

In the assist spring 5, the spring constant of the first spring 51 is larger than the spring constant of the second spring 52. The first spring 51 is made of a wire rod 50A having a square cross section, the second spring 52 is made of a wire rod 50B having a circular cross section, and the wire diameters of the wire rod 50A and the wire rod 50B are the same. When the wire diameters are the same, the spring constant of the coil spring formed of the wire having a square cross section is larger than that of the coil spring formed of the wire having a circular cross section.

Further, in the assist spring 5, the working angle range (first working angle range) of the first spring 51 having a large spring constant is smaller than the working angle range (second working angle range) of the second spring 52 having a small spring constant. As described above, when the action start position R1 of the first spring 51 is 50 ° and the action start position R2 of the second spring 52 is 20 °, when the opening / closing member is rotated from the closed position to the open position, The second spring 52, which has a smaller spring constant, starts to generate the urging force first.

(Main effect of this form)
As described above, the opening / closing member driving device 1 of the present embodiment includes the case 10, the output shaft 2 protruding from the case 10, the motor 3 housed in the case 10, and the rotation of the motor 3 housed in the case 10. Assist to urge the output shaft 2 to the second rotation direction CCW opposite to the first rotation direction CW as the output shaft 2 rotates in the first rotation direction CW. It has an assist spring 5 for generating a force. The assist spring 5 includes a first spring 51 and a second spring 52 arranged on the inner peripheral side of the first spring 51, and the first spring 51 and the second spring 52 are torsion coil springs. The case 10 includes an intermediate plate 161 that partitions the internal space, and a support portion 6 and ribs 7 that project from the intermediate plate 161 toward the output shaft 2. The support portion 6 rotatably supports the output shaft 2 and is arranged on the inner peripheral side of the second spring 52. Further, the rib 7 is arranged between the first spring 51 and the second spring 52.

According to this embodiment, the assist spring 5 for urging the output shaft 2 includes a first spring 51 and a second spring 52 arranged on the inner peripheral side of the first spring 51, and is arranged in a double manner. It is equipped with two torsion coil springs. The case 10 includes an intermediate plate 161 that partitions the internal space in the first direction Z, and a support portion 6 arranged on the inner peripheral side of the assist spring 5 projects from the intermediate plate 161, and further, with the first spring 51. Ribs 7 arranged between the second springs 52 project. By arranging the rib 7 provided in the case 10 between the first spring 51 and the second spring 52 in this way, it is possible to prevent the first spring 51 and the second spring 52 from interfering with each other. Therefore, there is little possibility that the first spring 51 and the second spring 52 interfere with each other to perform normal spring operation, and the spring force as designed cannot be obtained. Further, there is little possibility that an abnormal stress is generated due to the interference between the first spring 51 and the second spring 52 and the durability is impaired.

In the present embodiment, at least the arc portion 72A of the outer peripheral edge of the rib 7 has a shape along the inner circumference of the first winding 510A of the first spring 51. Therefore, the rib 7 allows the first spring 51 to be moved from the inner circumference side. Since it can be guided, the position accuracy of the first spring 51 can be improved. Further, since the deformation of the first spring 51 can be suppressed, the interference between the first spring 51 and the second spring 52 can be suppressed.

Further, a radial gap S is provided between the arc portion 72A of the rib 7 and the first winding 510A of the first spring 51. By providing a certain amount of gap S between the rib 7 and the first spring 51 in this way, the contact between the first spring 51 and the rib 7 even when the first spring 51 is deformed by the rotation of the output shaft 2 Can be suppressed. Therefore, it is possible to suppress a decrease in durability due to contact between the first spring 51 and the rib 7.

In the present embodiment, since the rib 7 includes a protruding portion 73 protruding outward in the radial direction of the first spring 51, the linear portion 513 of the first spring 51 can be locked by the protruding portion 73. Therefore, the protrusion 73 can stop the rotation of the first spring 51.

In the present embodiment, the intermediate plate 161 is provided with an opening 164 in which the end portion of the first spring 51 is arranged, and the rib 7 has a protruding portion 73 protruding toward the opening 164. It functions as a guide portion for extending the spring end portion of the first spring 51 toward the opening 164. Therefore, the position accuracy of the first spring 51 can be improved. Further, since the positioning of the first spring 51 at the time of assembly is easy, the assembly work is easy.

The rib 7 of this embodiment functions as a receiving portion in which the protruding portion 73 supports a part of the first spring 51. Therefore, for example, the intermediate plate 161 can support the winding start portion of the first winding 510A, and the receiving portion (protruding portion 73) can support the winding end portion of the first winding 510A. As a result, the inclination of the first spring 51 can be suppressed. Therefore, it is possible to prevent the first spring 51 and the second spring 52 from interfering with each other.

In this embodiment, the height of the rib 7 is lower than the wire diameter of the first spring 51, so that the first spring 51 can be prevented from floating from the intermediate plate 161. Therefore, since the first spring 51 can be supported in a stable state by the intermediate plate 161, the inclination of the first spring 51 can be suppressed.

In this embodiment, the rib 7 has a tapered shape in which the width in the radial direction becomes narrower as the distance from the protrusion 73 in the circumferential direction increases. As a result, the radial gap between the first spring 51 and the second spring 52 and the rib 7 can be increased as the distance from the protruding portion 73 in the circumferential direction increases. Therefore, it is possible to provide a certain amount of gap between each portion of the first roll 510A and the rib 7 while improving the positional accuracy of the first end portion 511 arranged in the opening 164. Therefore, when the first spring 51 is deformed by the rotation of the output shaft 2, the contact between the first spring 51 and the rib 7 can be suppressed. Therefore, it is possible to suppress a decrease in durability due to contact between the first spring 51 and the rib 7.

In this embodiment, since the inner peripheral edge 71 of the rib 7 has a shape along the outer circumference of the second spring 52, the second spring 52 can be guided from the outer peripheral side. Therefore, the position accuracy of the second spring 52 can be improved. Further, since the deformation of the second spring 52 can be suppressed, the interference between the first spring 51 and the second spring 52 can be suppressed.

In this embodiment, the support portion 6 arranged on the inner peripheral side of the second spring includes a groove portion 61 extending in the radial direction, and the first end portion 521 of the second spring 52 is arranged in the groove portion. The groove portion 61 has a shape in which the groove width increases from the radial center P of the support portion 6 toward the outside in the radial direction. As a result, the first end portion 521 of the second spring 52 can be freely tilted in the groove portion 61 in the circumferential direction to some extent. Therefore, when the output shaft 2 rotates, it is possible to prevent the urging force of the second spring 52 from being generated from the reference position to a predetermined angle.

In this embodiment, the rib 7 arranged between the first spring 51 and the second spring 52 has an opening 164 in which the spring end portion of the first spring 51 is arranged and a radial center P of the support portion 6. Since the shape is symmetrical with respect to the straight line L0 connecting the springs 51, the first spring 51 can be mounted in the opposite direction. Therefore, it is not necessary to change the shape of the rib 7 depending on the rotation direction of the output shaft 2, and it is not necessary to change the shape of the case 10, so that the parts can be shared.

1 ... Opening / closing member drive device, 2 ... Output shaft, 3 ... Motor, 4 ... Transmission mechanism, 5 ... Assist spring, 6 ... Support part, 7 ... Rib, 8 ... Potential meter, 9 ... Opening, 10 ... Case, 11 ... 1st side wall, 12 ... 2nd side wall, 13 ... 3rd side wall, 14 ... 4th side wall, 15 ... 1st case, 16 ... intermediate case, 17 ... 2nd case, 18 ... reinforcing member, 19 ... O ring, 21 ... base, 22 ... connecting shaft, 23 ... convex, 24 ... circular recess, 25 ... spring locking hole, 30 ... motor body, 31 ... rotating shaft, 32 ... bearing member, 33 ... receiving part, 34 ... spring receiving part , 40 ... worm, 41 ... 1st gear, 42 ... 2nd gear, 43 ... 3rd gear, 44 ... 4th gear, 45 ... output gear, 46 ... torque limiter, 50A ... wire rod, 50B ... wire rod, 61 ... groove , 71 ... Inner peripheral edge, 72A, 72B ... Arc part, 73 ... Protruding part, 74A, 74B ... Straight part, 81 ... Potential gear, 82 ... Detection part, 100 ... Western style toilet, 110 ... Toilet body, 120 ... Toilet seat, 130 ... Toilet lid, 140 ... Tank, 151 ... Bottom plate, 152 ... Frame part, 153 ... Spring holding part, 154 ... Spring locking hole, 155 ... Inclined surface, 161 ... Intermediate plate, 162 ... Intermediate frame part, 163 ... Opening , 164 ... Opening, 165 ... Frame part, 181 ... Reinforcing member side opening, 182 ... Shaft holding part, 183 ... Output gear receiving part, 411 ... First large diameter gear, 412 ... First small diameter gear, 413 ... 1 support shaft, 421 ... 2nd large diameter gear, 422 ... 2nd small diameter gear, 423 ... 2nd support shaft, 431 ... 3rd large diameter gear, 432 ... 3rd small diameter gear, 433 ... 3rd support shaft, 450 ... Circular portion, 451 ... Center hole, 452 ... Recess, 453 ... Notch, 454 ... First surface, 455 ... Second surface, 510A ... 1st roll, 510 ... Spring part, 511 ... 1st end, 512 ... 2nd end, 513 ... Linear part, 520 ... Spring part, 521 ... 1st end, 522 ... 2nd end, CCW ... 2nd rotation direction, CW ... 1st rotation direction, L ... Output shaft Axial line, L1 ... Motor rotation center line, L0 ... Straight line connecting the opening and the radial center of the support, P ... Radial center of the support, R1 ... First action start position, R2 ... Second action Start position, S ... radial gap, X ... third direction, Y ... second direction, Z ... first direction

Claims

With the case
The output shaft protruding from the case and
The motor housed in the case and
A transmission mechanism housed in the case and transmitting the rotation of the motor to the output shaft,
It has an assist spring that generates an assist force that urges the output shaft in the second rotation direction opposite to the first rotation direction as the output shaft rotates in the first rotation direction.
The assist spring includes a first spring and a second spring arranged on the inner peripheral side of the first spring, and the first spring and the second spring are torsion coil springs.
The case includes an intermediate plate that partitions an internal space, and a support portion and ribs that project from the intermediate plate toward the output shaft, and the support portion rotatably supports the output shaft.
The support portion is arranged on the inner peripheral side of the second spring.
An opening / closing member driving device characterized in that the rib is arranged between the first spring and the second spring.
The opening / closing member driving device according to claim 1, wherein at least a part of the outer peripheral edge of the rib has a shape along the inner circumference of the first winding of the first spring.
The opening / closing member driving device according to claim 1 or 2, wherein a gap in the radial direction is provided between the rib and the first winding of the first spring.
The opening / closing member driving device according to any one of claims 1 to 3, wherein the rib includes a protruding portion protruding outward in the radial direction of the first spring.
The intermediate plate comprises an opening in which the end of the first spring is located.
The opening / closing member driving device according to claim 4, wherein the protruding portion projects toward the opening.
The opening / closing member driving device according to claim 5, wherein the protruding portion is a receiving portion that supports a part of the first spring.
The opening / closing member driving device according to claim 6, wherein the height of the rib is lower than the wire diameter of the first spring.
The opening / closing member driving device according to any one of claims 4 to 7, wherein the rib has a tapered shape in which the width in the radial direction becomes narrower as the distance from the protruding portion in the circumferential direction increases.
The opening / closing member driving device according to any one of claims 1 to 8, wherein the inner peripheral edge of the rib has a shape along the outer periphery of the second spring.
The support portion includes a groove portion extending in the radial direction, and an end portion of the second spring is arranged in the groove portion.
The opening / closing member driving device according to any one of claims 1 to 9, wherein the groove width increases from the radial center of the support portion toward the outer side in the radial direction.
The opening / closing member driving device according to any one of claims 5 to 7, wherein the rib has a symmetrical shape with respect to a straight line connecting the opening and the radial center of the support portion. ..