CN211429096U

CN211429096U - Opening and closing member drive device

Info

Publication number: CN211429096U
Application number: CN202020368416.XU
Authority: CN
Inventors: 石水昭夫
Original assignee: Nidec Sankyo Corp
Current assignee: Nidec Instruments Corp
Priority date: 2019-03-28
Filing date: 2020-03-20
Publication date: 2020-09-04
Anticipated expiration: 2030-03-20
Also published as: JP2020162693A; JP7309409B2

Abstract

An opening/closing member driving device capable of coping with various load patterns. The opening/closing member drive device (1) is provided with: an output shaft (2) protruding from a housing (10), a motor (3) as a drive source, a transmission mechanism (4) that transmits the rotation of the motor (3) to the output shaft (2), and an assist spring (5) that biases the output shaft (2). The auxiliary spring (5) is provided with: a first spring (51), the first spring (51) generating an assist force while the rotational position of the output shaft (2) is within a first operating angle range (e.g., 50 DEG to 120 DEG); and a second spring (52), wherein the second spring (52) generates an assisting force when the rotational position of the output shaft (2) is within a second operating angle range (for example, 20 DEG to 120 DEG).

Description

Opening and closing member drive device

Technical Field

The utility model relates to a switching part drive arrangement, it possesses the output shaft of connecting the switching part, drives the driving source of output shaft and accommodates the casing of driving source.

Background

As an opening/closing member drive device for opening/closing an opening/closing member such as a toilet seat and a toilet lid of a western-style toilet, a device is used in which rotation of a drive source such as a motor is transmitted to an output shaft via a transmission mechanism such as a gear train. Patent document 1 discloses such an opening/closing member driving device (lid opening/closing device). In the lid body opening/closing device of patent document 1, an auxiliary spring that urges an output shaft to assist opening/closing of an opening/closing member is incorporated. In addition, a torque limiter is incorporated to prevent an excessive load from being applied to the motor and the transmission mechanism to damage the motor and the transmission mechanism when the opening and closing member is suddenly opened and closed.

Documents of the prior art

Patent document

Patent document 1: japanese patent laid-open publication No. 2014-200458

SUMMERY OF THE UTILITY MODEL

Technical problem to be solved by the utility model

In the lid opening and closing device of patent document 1, the motor and the reduction gear set are housed in the case. The output shaft includes a gear portion that meshes with a final gear of the reduction gear set, and a shaft portion that extends in the axial direction from the center of the gear portion, and the tip of the shaft portion protrudes outside the housing. The auxiliary spring is disposed on the outer peripheral side of the shaft portion. One end of the assist spring is locked to a fixing hole provided in an end face of the gear portion. The other end of the auxiliary spring is locked to a locking portion provided on an inner wall of the housing.

In patent document 1, the assist spring is a coil spring, and an elastic force (assist force) for urging the output shaft is generated by one assist spring. However, since the relationship between the rotational position of the output shaft and the assist force is a simple proportional relationship in one assist spring, the assist force cannot be flexibly set, and it is not possible to cope with various load patterns.

In view of the above problems, an object of the present invention is to provide an opening/closing member drive device including an output shaft connected to an opening/closing member, in which the degree of freedom in setting an elastic force (assist force) for biasing the output shaft is improved so as to be able to cope with various load patterns.

Technical scheme for solving technical problem

In order to solve the above technical problem, the utility model provides a switching part drive arrangement which characterized in that has: a housing; an output shaft protruding from the housing; a motor housed in the case; a transmission mechanism housed in the case and transmitting rotation of the motor to the output shaft; and an assist spring that generates an assist force that urges the output shaft in a second rotational direction opposite to the first rotational direction in accordance with rotation of the output shaft in the first rotational direction, the assist spring including a first spring that generates the assist force when a rotational position of the output shaft is a position within a first operation angle range, and a second spring that generates the assist force when the rotational position of the output shaft is a position within a second operation angle range different from the first operation angle range.

According to the present invention, the two springs that generate the elastic force (the assist force) and have different ranges of the angle of action are provided as the assist spring for applying the force to the output shaft. By thus combining a plurality of springs to generate the assist force, the degree of freedom in setting the assist force is improved as compared with the case where the assist force is generated by one spring. Therefore, various load patterns can be dealt with. Further, by combining a plurality of springs having different operating angle ranges, the assist force can be set for each angle range. For example, in the state where the opening/closing member is closed, the assisting force can be strengthened because a load by the load of the opening/closing member is applied, and in the state where the opening/closing member is opened, the assisting force can be reduced because the load is small. In addition, by combining a plurality of assist springs, the degree of freedom of the spring shape and the wire diameter can be improved. In addition, the degree of freedom of the mounting method can be improved.

In the present invention, the spring constant of the first spring is larger than the spring constant of the second spring. In this way, by combining springs having different spring constants, the degree of freedom in setting the assist force is improved, and thus, various load modes can be accommodated.

In the present invention, it is preferable that the first spring and the second spring are torsion coil springs, the second spring is disposed on an inner peripheral side of the first spring, and a spring constant of the first spring is larger than a spring constant of the second spring. In this way, by arranging two springs in a double manner, a plurality of springs can be arranged in a limited arrangement space. Further, since the spring having a large spring constant has high strength, the inner spring can be protected by disposing it on the outer side.

In the present invention, it is preferable that the output shaft includes a resin portion, the transmission mechanism includes a metal output gear fixed to the resin portion, the first spring is engaged with the output gear, and the second spring is engaged with the resin portion. With this configuration, the metal output gear can support the spring having a larger spring constant (i.e., the spring that is less likely to deform), and the resin portion can support the spring having a smaller spring constant (i.e., the spring that is more likely to deform). Therefore, the risk of deformation and damage of the output shaft caused by the load applied from the spring side is small.

In the present invention, it is desirable that the first operation angle range is narrower than the second operation angle range. With this configuration, since the section in which the elastic force of only one of the weak springs acts can be provided, the section in which the assist force is weak can be provided.

The first spring is formed of a wire rod having a rectangular cross section, and the second spring is formed of a wire rod having a circular cross section. The strength of a wire rod having a rectangular cross section is higher than that of a wire rod having the same diameter and a circular cross section. Therefore, a spring having a large spring constant can be formed without increasing the wire diameter.

In the present invention, it is preferable that the housing includes a spring holding portion provided with a spring locking hole in which an end portion of the first spring or the second spring is disposed, and the spring holding portion is supported by the motor from a direction intersecting an opening direction of the spring locking hole. With this configuration, the risk of deformation or damage of the housing due to a load applied to the housing from the spring end can be reduced.

(effects of utility model)

According to the present invention, the two springs that generate the elastic force (the assist force) and have different ranges of the angle of action are provided as the assist spring for applying the force to the output shaft. By thus combining a plurality of springs to generate the assist force, the degree of freedom in setting the assist force is improved as compared with the case where the assist force is generated by one spring. Therefore, various load patterns can be dealt with. Further, by combining a plurality of springs having different operating angle ranges, the assist force can be set for each angle range. For example, in the state where the opening/closing member is closed, the load applied to the opening/closing member is applied to the opening/closing member, and therefore, the assisting force can be enhanced, and in the state where the opening/closing member is opened, the load is small, and therefore, the assisting force can be reduced.

Drawings

Fig. 1 is an external perspective view of an opening/closing member driving device to which the present invention is applied.

Fig. 2 is an explanatory diagram of a western-style toilet including the opening/closing member drive device 1 of fig. 1.

Fig. 3 is a sectional view of the opening and closing member driving device of fig. 1.

Fig. 4 is an exploded perspective view of the opening and closing member driving device of fig. 1.

Fig. 5 is a perspective view of the motor, the driving force transmission mechanism, and the output shaft when viewed from the other side in the first direction.

Fig. 6 is an exploded perspective view of the output gear and the output shaft.

Fig. 7 is an exploded perspective view of the output gear, the output shaft, and the assist spring.

Fig. 8 is a perspective view of the first housing and the intermediate housing as viewed from the other side in the first direction.

Fig. 9 is an explanatory diagram showing a state of the assist spring when the output shaft is at the reference position.

Fig. 10 is an explanatory diagram showing a state of the assist spring when the output shaft is at the action start position of the second spring.

Fig. 11 is an explanatory diagram showing a state of the assist spring when the output shaft is at the action start position of the first spring.

Description of the reference numerals

1 … opening and closing member driving device; 2 … output shaft; 3 … electric motor; 4 … transfer mechanism; 5 … auxiliary spring; 6 … a support portion; 7 … ribs; 8 … potentiometer; 9 … opening part; 10 … a housing; 11 … a first side wall; 12 … second side wall; 13 … a third side wall; 14 … fourth side wall; 15 … a first housing; 16 … a middle shell; 17 … a second housing; 18 … a reinforcing member; 19 … O-ring; 21 … a base; 22 … connecting shaft; 23 … protrusions; 24 … circular recesses; 25 … spring catch holes; 30 … motor body; 31 … rotating shaft; a 32 … bearing member; 33 … a bay; 34 … spring receivers; a 40 … worm; 41 … a first gear; 42 … second gear; 43 … third gear; 44 … fourth gear; 45 … output gear; 46 … torque limiter; 50A … wire; 50B … wire; 61 … groove parts; 71 … inner periphery; 72A, 72B … arc portions; 73 … projection; 74A, 74B … straight portions; 81 … potentiometer gear; 82 … detection part; 100 … western style toilet; 110 … toilet body; 120 … toilet seat; 130 … toilet lid; 140 … water tank; 151 … bottom panel; 152 … frame portion; 153 … spring holding parts; 154 … spring retention holes; 155 … inclined plane; 161 … intermediate plate; 162 … middle frame portion; 163 … opening; 164 … opening; 165 … box section; 181 … reinforcing the member-side opening; 182 … shaft holding part; 183 … output gear receiving part; 411 … first large diameter gear; 412 … a first small diameter gear; 413 … first fulcrum; 421 … second large diameter gear; 422 … second small diameter gear; 423 … second fulcrum; 431 … third large diameter gear; 432 … third small diameter gear; 433 … third fulcrum; 450 … annular portion; 451 … center hole; 452 … recesses; 453, 453 … notch portion; 454 … a first face; 455 … second side; 510a … first turn, 510 … spring portion; 511 … a first end; 512 … second end; 513 … straight line portion; 520 … spring portion; 521 … a first end; 522 … second end; CCW … second direction of rotation; CW … first direction of rotation; the axis of the L … output shaft; the rotational centerline of the L1 … motor; r1 … first effect start position; r2 … second effect start position; a third direction of X …; a second direction of Y …; z … first direction

Detailed Description

Embodiments of the present invention will be described below with reference to the drawings. Fig. 1 is an external perspective view of an opening/closing member drive device 1 to which the present invention is applied. Fig. 2 is an explanatory diagram of a western-style toilet 100 including the opening/closing member drive device 1 of fig. 1. Fig. 3 is a sectional view of the opening/closing member driving device 1 of fig. 1. Fig. 4 is an exploded perspective view of the opening/closing member driving device 1 of fig. 1. Fig. 5 is a perspective view of the motor 3, the transmission mechanism 4, and the output shaft 2 when viewed from the other side Z2 in the first direction Z.

In the present specification, three directions orthogonal to each other are referred to as a first direction Z, a second direction Y, and a third direction X. The first direction Z is a direction of the axis L of the output shaft 2, the second direction Y is a longitudinal direction of the housing 10, and the third direction X is a short-side direction (width direction) of the housing 10. Further, one side in the first direction Z is Z1, the other side is Z2, one side in the second direction Y is Y1, the other side is Y2, one side in the third direction X is X1, and the other side is X2. The side of the output shaft 2 protruding from the housing 10 is the other side Z2 in the first direction Z, and the side of the housing 10 on which the output shaft 2 is disposed is the one side Y1 in the second direction Y.

(Overall Structure)

The opening/closing member driving device 1 shown in fig. 1 is a device for opening/closing an opening/closing member such as a lid or a door by rotating the opening/closing member. The western-style toilet 100 shown in fig. 2 has a toilet body 110, a toilet seat 120, a toilet lid 130, and a water tank 140. The toilet seat 120 and the toilet lid 130 are connected to an output shaft 2 (see fig. 3) of the opening/closing member drive device 1. The toilet seat 120 and the toilet lid 130 are displaced by the rotation of the output shaft 2 to a closed position where they are covered on the toilet body 110 and an open position where they stand from the toilet body 110. Furthermore, the western-style toilet 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 drive device 1 includes a motor 3, an output shaft 2, a transmission mechanism 4 for transmitting a drive force of the motor 3 to the output shaft 2, an assist spring 5 for biasing the output shaft 2, and a housing 10 for housing the motor 3 and the transmission mechanism 4. The output shaft 2 includes a base 21 housed in the housing 10 and a connecting shaft 22 protruding from the opening 9 of the housing 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 housing 10 has a shape elongated 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 housing 10 in which the output shaft 2 is disposed is located at one end of the housing 10 in the second direction Y, which is the longitudinal direction.

The case 10 is made of resin. As shown in fig. 1, the housing 10 includes a first side wall 11 and a second side wall 12 extending parallel to the second direction Y. The housing 10 includes a third side wall 13 connecting one end of the other side Y2 of the first side wall 11 and the second side wall 12 in the second direction Y, and a fourth side wall 14 connecting one end of the one side Y1 of the first side wall 11 and the second side wall 12 in the second direction Y. 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 in the second direction Y. In the present embodiment, the fourth side wall 14 is a semicircular curved surface when viewed from the other side Z2 in the first direction Z.

As shown in fig. 1 and 3, the casing 10 includes a first casing 15, an intermediate casing 16, and a second casing 17 arranged along the first direction Z. The first casing 15 is located on one side Z1 of the intermediate casing 16 in the first direction Z, and the second casing 17 is located on the other side Z2 of the intermediate casing 16 in the first direction Z. 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 casing 15 includes a bottom plate 151 and a frame portion 152 extending from an 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 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 casing 10. The motor 3 is fixed to the first housing 15. The motor 3 includes a motor main body 30 and a rotating shaft 31 protruding from the motor main body 30. The rotary shaft 31 faces a direction intersecting the axis L of the output shaft 2. In the present embodiment, the rotation center line L1 (see fig. 4) of the rotary shaft 31 is orthogonal to the axis L of the output shaft 2. In addition, the rotation shaft 31 is inclined with respect to the second direction Y (the longitudinal direction of the housing 10) when viewed from the first direction Z. The front end of the rotary shaft 31 is rotatably supported by a bearing member 32 held by the first housing 15.

The intermediate case 16 includes an intermediate plate 161 and an intermediate frame portion 162 extending from an outer peripheral edge of the intermediate plate 161 to the other side Z2 in the first direction Z. The middle frame portion 162 constitutes a middle 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 casing 10. Some of the gears constituting the transmission mechanism 4 are housed in an intermediate case 16. Further, the base portion 21 of the output shaft 2 is housed in the intermediate case 16.

The plate-like reinforcing member 18 is fixed to the end of the intermediate case 16 on the second case 17 side. The rigidity of the reinforcing member 18 is higher than that of the case 10. In the present embodiment, 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 protrudes 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 disposed at an end portion on the opposite side (the other side Y2 in the second direction Y) from the output shaft 2 in the second direction Y.

The potentiometer 8 includes a potentiometer gear 81 (see fig. 5) that meshes with any one of a plurality of gears constituting the transmission mechanism 4, and a detection unit 82 (see fig. 3 and 4) that detects a rotational angle position of the potentiometer gear 81. The detection unit 82 includes a circuit board. The potentiometer gear 81 is positioned on one side Z1 in the first direction Z of the reinforcing member 18, and meshes with a third small-diameter gear of the third gear. The detection portion 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 housing 17 is plate-shaped, and covers the intermediate housing 16 from the other side Z2 in the first direction Z. The second case 17 is connected to an end of the other side Z2 of 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, and covers the reinforcing member 18 from the other side Z2 of the first direction Z. The second case 17 includes an opening 9 that penetrates through a portion overlapping with the reinforcing member side opening 181 when viewed in the first direction Z. As shown in fig. 3, a gap between the output shaft 2 disposed in the opening 9 and the inner peripheral surface of the opening 9 is sealed by an O-ring 19.

As shown in fig. 5, the transmission mechanism 4 includes a worm 40, a first gear 41, a second gear 42, a third gear 43, a fourth gear 44, and an output gear 45 from the upstream side to the downstream side of the drive force transmission path. The worm 40 is fixed to the outer peripheral side of the rotary shaft 31 of the motor 3. As shown in fig. 4, the worm 40 and the first gear 41 are disposed in the first housing 15. As shown in fig. 3, the second gear 42, the third gear 43, the fourth gear 44, and the output gear 45 are disposed in the intermediate housing 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 a smaller outer diameter than the first large-diameter gear 411. The first large-diameter gear 411 is located on one side Z1 in the first direction Z of the first small-diameter gear 412. The first gear 41 is rotatably supported by a first support shaft 413 (see fig. 4) extending in the first direction Z. One end of the first support shaft 413 is held by the bottom plate 151 of the first housing 15, and the other end is held by the intermediate plate 161 of the intermediate housing 16. The first gear 41 includes a torque limiter 46 that maintains and blocks transmission of the driving force between the first large-diameter gear 411 and the first small-diameter gear 412.

The second gear 42 is a composite gear including a second large-diameter gear 421 meshing with the first small-diameter gear 412 and a second small-diameter gear 422 coaxial with the second large-diameter gear 421 and having a smaller outer diameter than the second large-diameter gear 421. The second large-diameter gear 421 is located on one side Z1 of the second small-diameter gear 422 in the first direction Z. 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 housing 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 is a composite gear including a third large-diameter gear 431 meshing with the second small-diameter gear 422 and a third small-diameter gear 432 coaxial with the third large-diameter gear 431 and having an outer diameter smaller than that of the third large-diameter gear 431. The third large-diameter gear 431 is located on one side Z1 in the first direction Z of the third small-diameter gear 432. The third gear 43 is rotatably supported by a third fulcrum 433 extending in the first direction Z. One end of the third support shaft 433 is held by the intermediate plate 161 of the intermediate case 16, and the other end thereof 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 aligned in the second direction Y. The fourth gear 44 is disposed coaxially with the second gear 42 and is rotatably supported by the second fulcrum 423. One end of the second support shaft 423 is held by the intermediate case 16, and the other end 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. The output shaft 2 made of resin is coaxially fixed to the output gear 45. The output gear 45 is an annular member having a center hole 451 that opens in the first direction Z. A plurality of recesses 452 are circumferentially provided on the inner peripheral surface of the center hole 451, and a plurality of protrusions 23 that fit into the recesses 452 on the inner peripheral surface of the output gear 45 are provided on the outer peripheral surface of the base portion 21 of the output shaft 2. Therefore, the output gear 45 and the output shaft 2 are connected in a state of being relatively non-rotatable about the axis L. The base portion 21 of the output shaft 2 is a resin portion and is fixed to the output gear 45 by heat caulking.

The output gear 45 is rotatably supported by the reinforcing member 18. The output gear 45 includes an annular portion 450 having no teeth on the outer peripheral surface at the end portion on the other side Z2 in the first direction Z. On the other hand, the reinforcing member 18 includes an output gear receiving portion 183 (see fig. 3) at an outer peripheral portion of the reinforcing member side opening portion 181, and rotatably supports the annular portion 450 of the output gear from the outer peripheral side. The output gear receiving portion 183 is an annular tube portion that extends while being bent toward the other side in the first direction of the reinforcing member side opening portion 181 of the reinforcing member 18, 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 fig. 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 disposed on the inner peripheral side of the first spring 51. The first spring 51 is located on one side Z1 of the first direction Z of the output gear 45. The second spring 52 is located on one side Z1 in the first direction Z of the output shaft 2 and on the inner peripheral side of the first spring 51.

As shown in fig. 7, the first spring 51 includes a spring portion 510 formed by winding a wire 50A having a rectangular cross section in a spiral shape, a first end portion 511 extending from the spring portion 510 to one side Z1 in the first direction Z, and a second end portion 512 extending from the spring portion 510 to the other side Z2 in the first direction Z. As shown in fig. 5, the second end portion 512 of the first spring 51 is disposed in the cutout portion 453, and the cutout portion 453 is formed by cutting the outer peripheral surface of the output gear 45 to the inner peripheral side. The output gear 45 has a tooth portion formed on the outer peripheral surface of the range excluding the notched portion 453. The cutout 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 described later, when the output shaft 2 rotates to a predetermined angular position, the second end 512 contacts 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 casing 15 and the intermediate casing 16 when viewed from the other side Z2 in the first direction Z. As shown in fig. 3 and 8, the intermediate case 16 includes the support portion 6 protruding 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 further than the first spring 51 and the second spring 52 toward the other side Z2 in the first direction Z. That is, the first spring 51 and the second spring 52 are held by the support portion 6 and are supported by the intermediate plate 161 from the first direction Z1 side.

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

The output shaft 2 and the output gear 45 are rotatably supported by the tip end portions of the support portions 6. The output shaft 2 is provided with a circular recess 24 recessed toward the other side Z2 on the end surface of one side Z1 in the first direction Z of the base 21, and the tip end portion of the support portion 6 is disposed in the circular recess 24 and contacts the bottom surface of the circular recess 24. Here, the other side Z2 in the first direction Z of the support portion 6 has a distal end extending to 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.

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

In the first housing 15, the spring holding portion 153 is supported by the motor 3 from a direction intersecting the first direction Z, which is a direction in which the spring locking hole 154 opens. That is, the motor 3 includes the 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 protrudes from the inner surface of the frame portion 152 of the first case 15 toward 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 parallel to the side surface of the motor main body 30 at the end portion on the other side X2 in the third direction X. When the motor 3 is housed in the first housing 15, the inclined surface 155 of the spring holding portion 153 is supported by the side surface of the motor main 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 formed of, for example, a metal motor case.

As shown in fig. 7, the second spring 52 includes a spring portion 520 formed by winding a wire 50B having a circular cross section in a spiral shape, a first end portion 521 bent radially inward from one end portion of the spring portion 520 at one side Z1 in the first direction Z and extending linearly, and a second end portion 522 extending from the spring portion 520 at the other side Z2 in the first direction Z. The first end 521 of the second spring 52 is disposed in the groove 61 provided in the support portion 6 (see fig. 8, 9 b, and 10 b), whereby the first end 521 of the second spring 52 is locked to the intermediate case 16, as shown in fig. 7, the output shaft 2 includes a spring locking hole 25 provided in the end surface of the other side Z2 of the base portion 21, and the second end 522 of the second spring 52 is disposed in the spring locking hole 25 of the output shaft 2.

As shown in fig. 8, the intermediate case 16 includes a rib 7 extending in the circumferential direction on the outer circumferential side of the support portion 6. The rib 7 protrudes from the intermediate plate 161 to the other side Z2 in the first direction Z. When first spring 51 and second spring 52 are attached to the outer peripheral side of support portion 6, one end of rib 7 in the circumferential direction is disposed between first spring 51 and second spring 52 (see fig. 3). The inner circumferential edge 71 of the rib 7 is circular-arc shaped. That is, the inner peripheral edge 71 of the rib 7 is shaped to follow the outer periphery of the spring portion 520 of the second spring 52, which is a spring disposed on the inner peripheral side. On the other hand, the outer peripheral edge of the rib 7 is provided with

circular arc portions

72A and 72B along the inner periphery of the spring portion 510 of the first spring 51 at both ends in the circumferential direction, and is provided with a protruding portion 73 protruding outward in the radial direction at the center in the circumferential direction. The protruding portion 73 is shaped to protrude inward of the opening 164. The outer peripheral edge of the rib 7 is provided with

linear portions

74A and 74B extending in the tangential direction of the arcuate portion 72 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 from a winding start position of the first turn 510A of the spring portion 510 in a tangential direction of the first turn 510A, and the first end 511 extends from a tip of the linear portion 513 to a side Z1 in the first direction Z. In the rib 7 provided on the intermediate case 16, the circular arc portion 72A provided at one end portion in the circumferential direction extends along the inner circumference of the winding start portion of the first turn 510A of the spring portion 510. Further, a straight portion 74A extending from the circular arc portion 72A to the tip of the protruding portion 73 extends along the straight portion 513. The first spring 51 is arranged in a state where the winding start portion and the linear portion 513 of the first turn 510A of the spring portion 510 extend along the outer peripheral edge of the rib 7. Thereby, the rotation stop of the first spring 51 is achieved by the protruding portion 73 of the rib 7, and the linear portion 513 of the first spring 51 is positioned at an angular position extending toward the opening portion 164.

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

(action)

In the opening/closing member drive device 1, when the motor 3 is driven in the forward direction or the reverse direction, the drive force of the motor 3 is transmitted to the output shaft 2 via the transmission mechanism 4, and the output shaft 2 rotates in the first rotation direction CW or the second rotation direction CCW. Thereby, the opening/closing member such as a toilet seat and a toilet lid fixed to the output shaft 2 is rotated in the opening direction or the closing direction. When the opening and closing member rotates, the potentiometer 8 outputs a signal corresponding to the position of the opening and closing member. When the opening/closing member connected to the output shaft 2 rotates in the first rotation direction CW, the assist spring 5 applies an elastic force to the output shaft 2 to rotate the output shaft 2 about the axis L in a second rotation direction CCW opposite to the first rotation direction CW. That is, when the opening/closing member is driven, an assisting force that urges the output shaft 2 is applied to the output shaft 2. Further, since the transmission mechanism 4 includes the torque limiter 46 in the first gear 41, when an excessive load is applied to the transmission mechanism 4 from the opening/closing member via the output shaft 2, the torque limiter 46 acts to block the transmission of the driving force by the transmission mechanism 4. This can prevent the transmission mechanism 4 from being damaged by an excessive load from the outside.

(range of angle of operation of auxiliary spring)

The first spring 51 and the second spring 52 of the assist spring 5 have different operating angle ranges (angle ranges in which the elastic force is generated). In the case where the opening/closing member is a toilet seat or a toilet lid, a load curve showing a relationship between a rotational load when the opening/closing member is rotated by a predetermined angle from a reference position and a rotational angle from the reference position is not a shape showing a simple proportional relationship. Therefore, by combining a plurality of springs having different operating angle ranges, a graph showing the relationship between the driving force of the motor 3 and the sum of the elastic forces of the first spring 51 and the second spring 52 and the rotation angle is made to approach the load curve.

Fig. 9 is an explanatory diagram showing a state of the assist spring 5 when the output shaft 2 is at the reference position R0. Fig. 10 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. Fig. 9 (a) and 10 (a) show the rotational position of the output shaft 2, and fig. 9 (b) and 10 (b) show the state of the assist spring 5. 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 R1 of the first spring 51.

As shown in fig. 9 (a), when the output shaft 2 is at the reference position R0, the second end portion 512 of the first spring 51 is located closer to the one side of the notch 453 of the output gear 453 in the circumferential direction and is away from the second surface 455. Therefore, the first spring 51 applies an elastic force to the output gear 45. As shown in fig. 9 (b), the first end 521 of the second spring 52 is located at the circumferential center of the groove 61 provided in the support portion 6. The groove 61 has the following shape: the circumferential width (groove width) increases from the center of the support portion 6 in the radial direction toward the radially outer side, and the first end portion 521 moves in the circumferential direction within a range not contacting the inner surface of the groove portion 61. Therefore, no elastic force is applied from the second spring 51 to the output shaft 2.

As shown in fig. 10 (a), when the output shaft 2 rotates in the first rotational direction CW to the action start position R2 of the second spring 52, the second end 512 of the first spring 51 approaches the second surface 455 but is still separated from the second surface 455. Therefore, the first spring 51 does not apply an elastic force to the output gear 45. On the other hand, as shown in fig. 10 (b), as the output shaft 2 rotates, the first end portion 521 of the second spring 52 is inclined in the first rotation direction CW in the groove portion 61 and contacts the inner surface of the groove portion 61. Therefore, when the output shaft 2 further rotates in the first rotation direction CW from this, the second spring 52 deforms and generates an elastic force.

Next, as shown in fig. 11, when the output shaft 2 further rotates in the first rotational direction CW and reaches the action start position R1 of the first spring 51, the second end 512 of the first spring 512 contacts the second surface 455. Therefore, when the output shaft 2 further rotates in the first rotation direction CW from this, the first spring 51 deforms and generates an elastic force. Thus, the assist spring 5 generates no assist force from the reference position R0 to the action start position R2 of the second spring 52, and generates only the second spring 52 with an elastic force from the action start position R2 to the action start position R1, so that the assist force is generated by only one spring. Since both the second spring 52 and the first spring 51 generate elastic force from the action start position R1, the resultant force thereof becomes the assist force.

In the present embodiment, when the rotation angle of the output shaft 2 at the reference position R0 is set to 0 ° and the rotation angle of the output shaft 2 at the maximum rotation position is set to Rmax °, the operation angle range (first operation angle range) of the first spring 51 is a range from the operation start position R1 of the first spring 51 to the maximum rotation position. The operation angle range (second operation angle range) of the second spring 52 is a range from the operation start position R2 of the second spring 52 to the maximum rotation position. For example, when Rmax ° is 120 ° and the rotation angle at the action start position R1 of the first spring 51 is 50 °, the first action angle range is 50 ° to 120 °. When the rotation angle at the operation start position R2 of the second spring 52 is 20 °, the second operation angle range is 20 ° to 120 °. Therefore, the assisting force is not generated until the output shaft 2 rotates 20 ° from the reference position R0, but the elastic force of the second spring 52 is the assisting force in the range of the rotation angle from the reference position R0 of 20 ° to 50 °, and the sum of the elastic force of the second spring 52 and the elastic force of the first spring 51 is the assisting force in the range of the rotation angle from the reference position R0 of 50 ° to 120 °.

The spring constant of the first spring 51 of the auxiliary spring 5 is larger than that of the second spring 52. The first spring 51 is formed of a wire 50A having a square cross section, the second spring 52 is formed of a wire 50B having a circular cross section, and the wire diameters of the

wires

50A and 50B are the same. When the wire diameter is the same, the spring constant of the coil spring formed of the wire rod having a square cross section is larger than the spring constant of the coil spring formed of the wire rod having a circular cross section.

In addition, the auxiliary spring 5 has a smaller operating angle range (first operating angle range) for the first spring 51 having a large spring constant than for the second spring 52 having a small spring constant. As described above, when the operation start position R1 of the first spring 51 is 50 ° and the operation start position R2 of the second spring 52 is 20 °, the second spring 52 having a small spring constant first starts to generate an elastic force when the opening/closing member is rotated from the closed position to the open position.

(main effect of the present embodiment)

As described above, the opening/closing member driving device 1 of the present embodiment includes: a housing 10; an output shaft 2 protruding from the housing 10; a motor 3 housed in the case 10; a transmission mechanism 4 housed in the casing 10 and transmitting rotation of the motor 3 to the output shaft 2; and an assist spring 5 that generates an assist force that urges the output shaft 2 in a second rotational direction CCW opposite to the first rotational direction CW in accordance with rotation of the output shaft 2 in the first rotational direction CW. The assist spring 5 includes a first spring 51 and a second spring 52, and the first spring 51 generates an assist force when the rotational position of the output shaft 2 is a position within a first operation angle range (for example, a rotational position within a range of 50 ° to 120 °), and the second spring 52 generates an assist force when the rotational position of the output shaft 2 is a position within a second operation angle range different from the first operation angle range (for example, a rotational position within a range of 20 ° to 120 °).

In the present embodiment, two springs having different ranges of angles of action for generating the elastic force (assist force) are provided as the assist spring 5 for urging the output shaft 2. In this way, by combining a plurality of springs to generate the assist force, the degree of freedom in setting the assist force is improved as compared with the case where the assist force is generated by one spring. Therefore, it is possible to cope with various load patterns. Further, by combining a plurality of springs having different operating angle ranges, the assist force can be set for each angle range. For example, the following structure is possible: in the closed position where the opening/closing member is closed, a load due to the load of the opening/closing member is applied, and therefore, the elastic forces of the two springs are made to act to reinforce the assisting force, and as the opening/closing member is opened, the load becomes smaller, and therefore, the springs that generate the elastic forces are reduced, and the assisting force becomes smaller.

In addition, by combining a plurality of assist springs 5 in this way, the degree of freedom of the spring shape and the wire diameter can be improved. That is, a large assisting force can be obtained without increasing the wire diameter. In addition, the degree of freedom of the mounting method can be improved. In the present embodiment, a space for arranging the assist spring 5 is secured not on the outer peripheral side of the output shaft 2 but on the outer peripheral side of the support portion 6 that rotatably supports the output shaft 2. This allows the first spring 51 and the second spring 52 to be arranged in a double manner.

In the present embodiment, the spring constant of the first spring 51 is larger than the spring constant of the second spring 52. In this way, by combining springs having different spring constants, the degree of freedom in setting the assist force is improved, and thus, various load modes can be accommodated. The second spring 52 is disposed on the inner peripheral side of the first spring 51, and the spring constant of the first spring 51 disposed on the outer peripheral side is larger than the spring constant of the second spring 52. In this way, by arranging two springs in a double manner, a plurality of springs can be arranged in a limited arrangement space. Further, since the spring having a large spring constant has high strength, the inner spring can be protected by being disposed outside.

In the present embodiment, the output shaft 2 is made of resin, the transmission mechanism 4 includes the metal output gear 45 fixed to the base portion 21 of the output shaft 2 as a resin portion, the first spring 51 is engaged with the output gear 45, and the second spring 52 is engaged with the resin portion. Therefore, the spring having the larger spring constant (i.e., the spring that is not easily deformed) can be supported by the output gear 45 made of metal, and the spring having the smaller spring constant (i.e., the spring that is easily deformed) can be supported by the output shaft 2 that is the resin portion, so that the risk of deformation or damage of the output shaft 2 due to a load applied from the spring side is small.

In the present embodiment, the first operating angle range in which the first spring 51 generates the spring force is narrower than the second operating angle range in which the second spring 52 generates the spring force. Therefore, since the section in which the elastic force of the second spring 52 acts, which is only the weaker spring, can be provided, the section in which the assist force is weak can be provided. Therefore, the degree of freedom in setting the assist force is improved.

In the present embodiment, the first spring 51 is formed of a wire 50A having a rectangular cross section, and the second spring 52 is formed of a wire 50B having a circular cross section. The strength of the wire 50A having a rectangular cross section is higher than that of the wire 50B having a circular cross section and the same diameter. Therefore, a spring having a large spring constant can be formed without increasing the wire diameter.

The magnitude relation between the ranges of the operating angles of the first spring 51 and the second spring 52 and the spring constants may be different from those described above, and may be set as appropriate according to the load curve when the opening/closing member is driven. The auxiliary spring 5 may be formed of three or more springs. The shape and the wire diameter of the wire forming the assist spring 5 are not limited to the above combination, and may be appropriately changed.

In the present embodiment, the first housing 15 includes the spring holding portion 153, the spring holding portion 153 is provided with the spring locking hole 154 in which the end portion of the first spring 51 is disposed, and the spring holding portion 153 is supported by the spring receiving portion 34 provided in the motor 3 from a direction intersecting the opening direction (the first direction Z) of the spring locking hole 154. Therefore, the risk of the first housing 15 being deformed or damaged by the load applied to the first housing 15 from the spring end can be reduced. The spring receiving portion 34 that supports the spring holding portion 153 is formed by a metal motor case. Therefore, the spring holding portion 153 can be supported by a component having high rigidity. Further, the end of the second spring 52 may be held instead of the first spring 51 with the same structure.

Claims

1. An opening/closing member driving device comprising:

a housing;

an output shaft protruding from the housing;

a motor housed in the case;

a transmission mechanism housed in the case and transmitting rotation of the motor to the output shaft; and

an assist spring that generates an assist force that urges the output shaft in a second rotational direction opposite to the first rotational direction in accordance with rotation of the output shaft in the first rotational direction,

the auxiliary spring is provided with: a first spring that generates the assist force during a period in which a rotational position of the output shaft is a position within a first operation angle range; and a second spring that generates the assist force during a period in which a rotational position of the output shaft is within a second angle range of action different from the first angle range of action.

2. The shutter drive device according to claim 1,

the spring constant of the first spring is greater than the spring constant of the second spring.

3. The shutter drive device according to claim 2,

the first spring and the second spring are torsion coil springs,

the second spring is disposed on the inner peripheral side of the first spring,

4. The shutter drive device according to claim 2,

the output shaft is provided with a resin part,

the transmission mechanism includes a metal output gear fixed to the resin portion,

the first spring is clamped with the output gear,

the second spring is engaged with the resin portion.

5. The shutter drive device according to claim 2,

the first angle of action range is narrower than the second angle of action range.

6. The shutter drive device according to claim 2,

the first spring is made of a wire rod with a rectangular section,

the second spring is formed of a wire rod having a circular cross section.

7. The opening-closing member driving device according to any one of claims 1 to 6,

the housing includes a spring holding portion provided with a spring locking hole in which an end portion of the first spring or the second spring is disposed,

the spring holding portion is supported by the motor from a direction intersecting an opening direction of the spring locking hole.