Motor with reduction mechanism

Abstract

Provided is a motor with a reduction mechanism that can suppress disengagement of the engagement of the gears from each other even when a large external force is applied to the output shaft. A support member (70) that maintains the engagement of the pinion gear (61) and the helical gear (62) is provided on the side opposite the helical gear (62) of the pinion gear (61) in the gear box (20). Thus, disengagement of the engagement of the gears from each other (the engagement of the pinion gear (61) and the helical gear (62)) can be suppressed even when a large external force is applied to the output shaft. As a result, damage to the pinion gear (61) and the helical gear (62) (the reduction mechanism (60)) can be prevented for a long period of time, and even the motor with a reduction mechanism (10) can be made long-lasting.

Description

Technical Field

[0001] The present invention relates to a motor with a speed reduction mechanism, which includes a motor part having a rotating shaft and a speed reduction mechanism part for reducing the rotation of the rotating shaft. Background Technology

[0002] Conventionally, the drive sources for windshield wiper systems or power window systems installed in vehicles such as automobiles have been small motors with reduction gears that can deliver large outputs. Such motors with reduction gears for vehicle use are described, for example, in Patent Document 1.

[0003] Patent Document 1 describes a motor with a speed reduction mechanism, comprising: a brushless motor having a pinion gear; and a helical gear having an output shaft that reduces the rotation of the pinion gear to produce an output. The pinion gear and the helical gear form a speed reduction mechanism and mesh with each other. Furthermore, the axis of the pinion gear and the axis of the output shaft are parallel to each other.

[0004] [Existing Technical Documents]

[0005] [Patent Literature]

[0006] [Patent Document 1] Japanese Patent Application Publication No. 2020-018035 Summary of the Invention

[0007] [The problem the invention aims to solve]

[0008] However, in the technology described in Patent Document 1, the pinion inside the gearbox is on the opposite side to the helical gear, forming a relatively large space. This space is necessary to accommodate the first ball bearing, which rotatably supports the pinion, into a designated location inside the gearbox.

[0009] Furthermore, since there is space on the opposite side of the pinion and helical gear, when a large external force is applied to the output shaft, a large load will be applied to the pinion via the helical gear, and the pinion may bend in a way that disengages from the helical gear. If the pinion bends, it will cause the engagement between the pinion and the helical gear to disengage.

[0010] The purpose of this invention is to provide a motor with a reduction mechanism that can prevent the gears from disengaging even when a large external force is applied to the output shaft.

[0011] [Technical means to solve the problem]

[0012] One embodiment of the present invention is a motor with a speed reduction mechanism, comprising: a motor part having a rotating shaft; and a speed reduction mechanism part for reducing the rotation of the rotating shaft. The motor with the speed reduction mechanism includes: a first gear integrally rotatably disposed on the rotating shaft; a second gear meshing with the first gear and rotating at a lower speed than the first gear; an output shaft disposed at the rotation center of the second gear; and a gearbox rotatably housing the first gear and the second gear. On the side of the first gear opposite to the side of the second gear in the gearbox, a meshing retaining member is provided to maintain the meshing of the first gear and the second gear.

[0013] [The effects of the invention]

[0014] According to the present invention, a meshing retaining member is provided on the opposite side of the first gear and the second gear in the gearbox to maintain the meshing of the first gear and the second gear, so that even when a large external force is applied to the output shaft, the meshing of the gears can be prevented from disengaging. Attached Figure Description

[0015] Figure 1 It is a cross-sectional view illustrating the internal structure of a motor with a speed reduction mechanism.

[0016] Figure 2 It is a three-dimensional view showing the inside of the gearbox.

[0017] Figure 3 This is a three-dimensional view showing the helical gear side of the bearing bracket.

[0018] Figure 4 It describes the gaps between parts. Figure 1 An enlarged view of part A of the dashed circle.

[0019] Figure 5 It is an exploded perspective view showing the bearing support, helical gear, and gearbox.

[0020] Figure 6 It is a three-dimensional diagram showing the output shaft, helical gear, pinion, rotor, and supporting components.

[0021] Figure 7 It is a perspective view showing a pair of supporting members surrounding the wall side.

[0022] Figure 8 It is a perspective view showing the fixed body part of the supporting component.

[0023] Figure 9 It refers to the gearbox and its supporting components, along... Figure 1 A cross-sectional view of the BB line.

[0024] Figure 10It describes the movement of the lubricating grease. Figure 1 An enlarged view of part A of the dashed circle.

[0025] Figure 11 This describes the positional relationship between the helical gear and its supporting components. Figure 1 The C-arrow diagram.

[0026] Figure 12 This is a perspective view illustrating embodiment 2 (bearing bracket).

[0027] Figure 13 This is a perspective view illustrating embodiment 3 (support member).

[0028] [Explanation of Symbols]

[0029] 10: Motor with a speed reduction mechanism

[0030] 11: Shell

[0031] 12: First sensor substrate

[0032] 12a: Hall sensor

[0033] 13: Second sensor substrate

[0034] 13a: MR sensor

[0035] 14: Bearing components

[0036] 15: O-ring

[0037] 16: Buckle

[0038] 20: Gearbox

[0039] 21: Bottom wall

[0040] 21a: Boss section (output shaft support section)

[0041] 21b: Reinforcing Ribs

[0042] 21c: Bearing component housing

[0043] 21d: First support protrusion (tilt suppression part)

[0044] 22: Side wall portion

[0045] 22a: Support member receiving part (engagement retaining member support part)

[0046] 22b: Screw hole

[0047] 22c: Inclined side surface (conical surface) of the shell

[0048] 23: Bearing bracket mounting section

[0049] 23a: Bearing bracket positioning recess

[0050] 30: Cover component

[0051] 31: Substrate holding section

[0052] 31a: Through hole

[0053] 32: Motor Housing Department

[0054] 32a: Shaft hole

[0055] 40: Bearing bracket

[0056] 41: Support body

[0057] 41a: Positioning convex part

[0058] 41b: Second support protrusion (tilt suppression part)

[0059] 41c: Screw hole

[0060] 41d: Through hole

[0061] 42: Secondary stent

[0062] 50: Brushless Motor (Motor Section)

[0063] 51: Stator core

[0064] 51a: Coil

[0065] 52: Rotor

[0066] 53: Rotation axis

[0067] 54: Rotor body

[0068] 60: Speed ​​reduction mechanism (Speed ​​reduction mechanism section)

[0069] 61: Small gear (first gear)

[0070] 61a: Spiral teeth

[0071] 62: Helical gear (second gear)

[0072] 62a: Gear body

[0073] 62b: Gear forming part

[0074] 62c: Helical teeth

[0075] 62d: Occlusal recess

[0076] 63: Output shaft

[0077] 70: Supporting component (engagement and retention component)

[0078] 71: Fixed body part

[0079] 71a: Female threaded portion (fixed portion)

[0080] 71b: Side inclined surface (conical surface) of the supporting member

[0081] 72: Enclosing wall section (second grease leakage prevention wall)

[0082] 72a: Inclined surface

[0083] 73: Annular wall section (first grease leakage prevention wall)

[0084] 73a: Pinion gear through hole

[0085] 80: Bearing bracket

[0086] 81: Annular platform

[0087] 82: Second support protrusion (tilt suppression part)

[0088] 90: Supporting components

[0089] 91: Another annular wall section (first grease leakage prevention wall)

[0090] BR: Bearing components

[0091] BR1: First ball bearing

[0092] BR2: Second ball bearing

[0093] BS: Base component

[0094] CC: Connector connection part

[0095] CN: External Connector

[0096] MG: Permanent Magnet

[0097] SF1: First Page

[0098] SF2: Second Side

[0099] SM: Sensor magnet

[0100] SP: Space

[0101] δS1: Micro-gap

[0102] δS2: Micro-gap

[0103] δS3: Micro-gap (gap)

[0104] δS4: Micro-gap

[0105] δS5: Micro-gap Detailed Implementation

[0106] Hereinafter, Embodiment 1 of the present invention will be described in detail using the accompanying drawings.

[0107] Figure 1 A cross-sectional view illustrating the internal structure of a motor with a speed reduction mechanism is shown. Figure 2 A perspective view showing the inside of the gearbox is shown. Figure 3 A perspective view showing the helical gear side of the bearing support is shown. Figure 4 This illustrates the gaps between parts. Figure 1 An enlarged view of part A of the dashed circle. Figure 5 An exploded perspective view showing the bearing support, helical gear, and gearbox is shown. Figure 6 A perspective view showing the output shaft, helical gear, pinion, rotor, and support components is provided. Figure 7 A perspective view showing a pair of sides surrounding the wall portion of the supporting member is shown. Figure 8 A perspective view showing the fixed body portion of the support member is shown. Figure 9 The diagram shows the gearbox and supporting components along... Figure 1 A cross-sectional view of the BB line. Figure 10 This illustrates the movement of the grease. Figure 1 Enlarged view of part A of the dashed circle. Figure 11 This illustrates the positional relationship between the helical gear and the supporting components. Figure 1 The C-arrow diagram.

[0108] [Overview of motors with speed reduction mechanisms]

[0109] Figure 1 The motor 10 with a reduction gear shown is used, for example, as a drive source for a windshield wiper unit mounted in a vehicle such as an automobile. Specifically, the motor 10 with the reduction gear causes a wiper component (not shown) to swing within a predetermined wiping range between a lower reverse position and an upper reverse position. The wiper component is disposed on the front side of the windshield (not shown) of the vehicle and is oscillating freely on the windshield.

[0110] The motor 10 with a reduction gear includes a housing 11 forming its outer contour. Inside the housing 11, a brushless motor 50 and a reduction gear 60 are rotatably housed. Furthermore, the brushless motor 50 corresponds to the motor section in this invention, and the reduction gear 60 corresponds to the reduction gear section in this invention.

[0111] Furthermore, inside the housing 11, a first sensor substrate 12 and a second sensor substrate 13, used to detect the rotational state of the rotor 52 and the helical gear 62, are respectively housed. The housing 11 also includes a gearbox 20 made of aluminum diecasting and a cover member 30 formed by stamping steel plates.

[0112] [Gearbox]

[0113] like Figure 1 as well as Figure 2 As shown, the gearbox 20 is formed into a roughly bowl-shaped form by injection molding molten aluminum. Specifically, the gearbox 20 includes a bottom wall portion 21, side wall portions 22 integrally formed around it, and a bearing mounting bracket 40 (see reference). Figure 3 ) Bearing bracket mounting part 23.

[0114] At approximately the center of the bottom wall portion 21, a cylindrical boss portion 21a is provided to rotatably support the output shaft 63. The boss portion 21a corresponds to the output shaft support portion in this invention. On the radially outer side of the boss portion 21a, a plurality of reinforcing ribs 21b formed in a generally triangular shape are provided. These reinforcing ribs 21b are the part that improves the fixing strength of the boss portion 21a relative to the bottom wall portion 21, and for example, eight are arranged at equal intervals along the circumference of the boss portion 21a.

[0115] A cylindrical bearing member 14, referred to as a "bearing (metal)," is installed on the radially inner side of the boss portion 21a. This allows the output shaft 63 to rotate smoothly relative to the boss portion 21a without wobbling. Additionally, on the front end side of the boss portion 21a ( Figure 1 An O-ring 15, made of elastic material such as rubber, is installed on the upper side and radially inward side of the output shaft 63. This prevents rainwater or dust from entering between the output shaft 63 and the bearing component 14.

[0116] Here, a retaining ring 16 is fixed at the center of the long side of the output shaft 63. The retaining ring 16 is snapped into the front end of the boss portion 21a. As a result, the boss portion 21a is clamped between the helical gear 62 and the retaining ring 16, and the output shaft 63 is in a state of being prevented from disengaging relative to the boss portion 21a. Therefore, the wobble of the output shaft 63 relative to the boss portion 21a is suppressed, and even more so, the quietness of the motor 10 with the reduction mechanism is ensured.

[0117] A bearing component receiving portion 21c is provided at a position eccentric to the boss portion 21a on the bottom wall portion 21. The bearing component receiving portion 21c is formed into a bottomed cylindrical shape and extends from the bottom wall portion 21 toward the outside of the gearbox 20. Figure 1The upper side protrudes. Furthermore, inside the bearing component housing 21c, a first ball bearing BR1 that rotatably supports the front end side of the pinion 61 is housed.

[0118] A support member receiving portion 22a is provided on the side wall portion 22 near the bearing bracket mounting portion 23. The support member receiving portion 22a corresponds to the engagement retaining member support portion in this invention and is disposed near the bearing member receiving portion 21c. A support member 70 is housed inside the support member receiving portion 22a. Here, the support member 70 is supported by the support member receiving portion 22a and is provided to cover the area around the pinion 61. Furthermore, the support member 70 functions to prevent the pinion 61 from bending when a large external force is applied to the output shaft 63.

[0119] Furthermore, a single screw hole 22b is provided in the support member housing portion 22a. The screw hole 22b faces radially toward the pinion 61 and the helical gear 62. Figure 1 The opening is located in the left and right directions. Furthermore, a fixing screw SC1 for securing the support member 70 to the support member receiving portion 22a is inserted into the screw hole 22b. Thus, the support member 70 is securely fixed inside the support member receiving portion 22a without wobbling. This also ensures the quietness of the motor 10 with the reduction gear.

[0120] like Figure 2 as well as Figure 9 As shown, inside the support member housing 22a, a pair of housing-side inclined surfaces 22c are provided. These housing-side inclined surfaces 22c interact with the pinion 61 and the helical gear 62 (see reference). Figure 1 The axially intersecting directions of the two components are opposite to each other. A pair of shell side inclined surfaces 22c are arranged on the support member 70 (see reference). Figure 7 as well as Figure 8 The front end of the gearbox 20 is positioned relative to the insertion direction of the support member receiving portion 22a. That is, a pair of housing-side inclined surfaces 22c are disposed on the portion of the gearbox 20 that is biased towards the bottom wall portion 21.

[0121] Furthermore, the pair of inclined surfaces 71b on the support member 70 (refer to...) Figures 7 to 9 ) are placed on a pair of inclined surfaces 22c on the sides of the shell. Thus, as Figure 9 As indicated by arrow M1, when the support member 70 is installed in the support member receiving portion 22a, a pair of support member side inclined surfaces 71b collide with a pair of housing side inclined surfaces 22c, thereby positioning (centering) the support member 70 at a predetermined position in the support member receiving portion 22a.

[0122] That is, the pair of inclined surfaces 22c on the housing side and the pair of inclined surfaces 71b on the support member side have the function of positioning the support member 70 relative to the support member receiving portion 22a in a standard position. Therefore, the subsequent tightening of the fixing screw SC1 can be easily performed (see reference). Figure 9 (arrow M2). In addition, a pair of shell side inclined surfaces 22c and a pair of support member side inclined surfaces 71b are respectively equivalent to the conical surfaces in this invention.

[0123] like Figure 1 as well as Figure 2 As shown, on the inner side of the bottom wall portion 21, that is, on the side of the bottom wall portion 21 opposite to the reinforcing rib 21b, a first support protrusion 21d formed in a generally annular shape is provided. The cross-section of the first support protrusion 21d is formed in a generally semi-circular shape and faces the inner side of the gearbox 20. Figure 1 The first support protrusion 21d protrudes at a predetermined height (on the lower side of the output shaft 63). It functions to suppress tilting of the helical gear 62 when a large external force is applied to the output shaft 63. Furthermore, the first support protrusion 21d corresponds to the tilt suppression part in this invention.

[0124] Moreover, such as Figure 2 As shown, a bearing bracket positioning recess 23a is provided in the bearing bracket mounting portion 23. The bearing bracket positioning recess 23a is provided to surround the support member receiving portion 22a and is recessed towards the support member receiving portion 22a. Furthermore, a positioning protrusion 41a (see reference 40) is provided in the bearing bracket 40. Figure 3 It fits into the positioning recess 23a of the bearing bracket.

[0125] Therefore, the bearing bracket 40 can be accurately installed in the standard position relative to the bearing bracket mounting part 23. Consequently, subsequent use of the fastening screw SC2 (see reference) can be easily performed. Figure 1 The bearing bracket 40 is fixed to the bearing bracket mounting portion 23, and the second ball bearing BR2 held by the bearing bracket 40 and the first ball bearing BR1 housed in the bearing member housing portion 21c are precisely and coaxially positioned. Therefore, deviations in the rotational resistance of the pinion 61 can be suppressed in each product.

[0126] [Bearing bracket]

[0127] like Figure 1 as well as Figure 3As shown, the bearing bracket 40, mounted on the bearing bracket mounting portion 23, holds the first sensor substrate 12 and the second ball bearing BR2, which rotatably supports the bottom end of the pinion 61. The bearing bracket 40 includes a bracket body 41 and a sub-bracket 42, which are formed facing each other. The second ball bearing BR2 is disposed between the bracket body 41 and the sub-bracket 42.

[0128] Furthermore, both the main support 41 and the sub-support 42 are made of die-cast aluminum, ensuring a secure and stable fixation relative to the gearbox 20 (bearing bracket mounting part 23) without wobbling. Moreover, Figure 3 Only the support body 41 that forms the bearing support 40 is shown in the diagram.

[0129] like Figure 3 As shown, a positioning protrusion 41a is provided on the helical gear 62 side of the bracket body 41, which fits into the positioning recess 23a of the bearing bracket (see reference). Figure 2 The positioning protrusion 41a is formed in a generally C-shape; and a pair of second support protrusions 41b are formed in a generally arc shape. In addition, the protrusion height of the positioning protrusion 41a is higher than the protrusion height of the pair of second support protrusions 41b.

[0130] Furthermore, with the bearing bracket 40 (bracket body 41) mounted on the gearbox 20 (bearing bracket mounting part 23), a pair of second support protrusions 41b face each other axially from the output shaft 63 toward the first support protrusion 21d provided on the gearbox 20 (see reference). Figure 1 That is, the pair of second support protrusions 41b also have the function of preventing the helical gear 62 from tilting when a large external force is applied to the output shaft 63. In addition, the cross-section of the pair of second support protrusions 41b is also formed in a generally semi-circular shape. Here, the pair of second support protrusions 41b corresponds to the tilt suppression part in the present invention.

[0131] Three screw holes 41c are provided on the outer periphery of the bracket body 41. Within these screw holes 41c, such as... Figure 1 As shown, fastening screws SC2 are inserted to secure the cover component 30 and the bearing bracket 40 to the gearbox 20. However... Figure 1 Only one fastening screw, SC2, is shown in the image.

[0132] Furthermore, a through hole 41d is provided at approximately the center of the support body 41 for the pinion 61 to be inserted in a non-contact manner. Additionally, the length of the pair of second support protrusions 41b is arbitrary and not limited to any particular dimension. Figure 3 The short length dimension shown by the solid line can also be set to a long length dimension as shown by the dashed arrow in this figure.

[0133] [Cover component]

[0134] like Figure 1 As shown, the cover member 30 forming the housing 11 includes a substrate holding portion 31 formed in a generally flat plate shape and a motor receiving portion 32 formed in a generally bottomed cylindrical shape. When the cover member 30 is mounted on the gearbox 20, the substrate holding portion 31 faces the helical gear 62 in the axial direction of the output shaft 63. Furthermore, a second sensor substrate 13 is fixed to the inside of the substrate holding portion 31 via a base member BS.

[0135] Furthermore, a through hole 31a is formed in the substrate holding portion 31 for the connector connection portion CC of the external connector CN on the vehicle side to be inserted. Here, the connector connection portion CC is fixed to the base member BS via a conductive member (not shown) and is electrically connected to the first sensor substrate 12, the second sensor substrate 13, and the brushless motor 50. As a result, the vehicle controller (not shown) connected to the external connector CN can drive the brushless motor 50 with good accuracy based on the detection signals from the first sensor substrate 12 and the second sensor substrate 13.

[0136] Here, three Hall sensors 12a (only one is shown in the figure) are mounted on the first sensor substrate 12. These Hall sensors 12a correspond to the U phase, V phase, and W phase, respectively. Furthermore, the three Hall sensors 12a are positioned axially opposite to the permanent magnet MG located on the rotor 52. Additionally, the vehicle controller uses the detection signals from the three Hall sensors 12a to determine the rotational state (rotational speed or direction, etc.) of the brushless motor 50 (pindle 61), thereby accurately controlling the rotation of the brushless motor 50.

[0137] On the other hand, a single MR sensor 13a is mounted on the second sensor substrate 13. The MR sensor 13a faces the sensor magnet SM, which is fixed to the rotation center of the helical gear 62, in the axial direction of the output shaft 63. Furthermore, the vehicle controller determines the rotational state (rotational position, etc.) of the output shaft 63 based on the detection signal of the MR sensor 13a, and accordingly controls the wiping position of the wiper component (not shown) relative to the windshield (not shown) with high precision.

[0138] With the cover member 30 installed in the gearbox 20, the motor housing 32 faces the side opposite to the gearbox 20 side. Figure 1 The motor housing 32 protrudes from the lower side. Furthermore, when the cover member 30 is installed in the gearbox 20, the motor housing 32 faces the bearing member housing 21c of the gearbox 20. A brushless motor 50 is housed inside the motor housing 32.

[0139] Furthermore, a shaft hole 32a is provided approximately at the center of the motor housing 32, and a bearing member BR is provided in the portion of the shaft hole 32a. The bearing member BR rotatably supports the bottom end of the long side of the rotating shaft 53 of the brushless motor 50. Figure 1 (on the lower side). Thus, the rotating shaft 53 containing the pinion 61 is rotatably supported by a total of three bearings (first ball bearing BR1, second ball bearing BR2, and bearing component BR).

[0140] [Brushless Motor]

[0141] The brushless motor 50 housed in the motor housing 32 includes a stator core (stator) 51 formed in a generally cylindrical shape. The stator core 51 is securely fixed inside the motor housing 32 in a state where it is stopped from rotating relative to the sub-support 42 of the bearing support 40 (details not shown).

[0142] The stator core 51 is formed by stacking multiple thin steel plates (magnetic bodies), and has multiple teeth (not shown) arranged radially on its outer side. Furthermore, the coils 51a corresponding to the U phase, V phase, and W phase are respectively wound onto these teeth by concentrated windings with a specified number of turns.

[0143] Furthermore, the on-board controller alternately supplies drive current to the coils 51a of the U-phase, V-phase, and W-phase at predetermined times, thereby causing the rotor (rotor) 52, located radially outside the stator core 51, to rotate in a predetermined direction with a predetermined drive torque. That is, the brushless motor 50 of this embodiment is an external rotor type brushless motor.

[0144] A rotor 52 is provided radially outside the stator core 51, rotating freely with a tiny gap (air gap). Figure 1 as well as Figure 6 As shown, the rotor 52 is a component that rotates the rotating shaft 53, which is integrally equipped with a pinion 61. It includes a rotor body 54, which is formed into a roughly U-shaped cross-section by stamping or other processes on a steel plate (magnetic material). Furthermore, a plurality of permanent magnets MG, formed into a roughly tile-like shape, are fixed to the radially inner side of the rotor body 54. The rotating shaft 53, which integrally provides the pinion 61, is securely fixed to the rotation center of the rotor body 54 by pressing or other methods.

[0145] [Speed ​​reduction mechanism]

[0146] like Figure 1 as well as Figure 6As shown, the reduction mechanism 60, rotatably housed within the housing 11 (gearbox 20), includes: a pinion (first gear) 61 integrally mounted on the rotating shaft 53; and a helical gear (second gear) 62 meshing with the pinion 61 and rotating at a lower speed than the pinion 61. Here, the axes of the pinion 61 and the helical gear 62 are parallel to each other. That is, the rotating shaft 53 and the output shaft 63 are parallel to each other. Therefore, the reduction mechanism 60 can be made more compact than a worm gear reducer that includes a worm and a worm wheel whose axes intersect.

[0147] Furthermore, the pinion 61 is positioned on the rotating shaft 53 side (inlet side) of the motor 10 with the reduction mechanism, and the helical gear 62 is positioned on the output shaft 63 side (outlet side) of the motor 10 with the reduction mechanism. That is, the reduction mechanism 60 reduces the high-speed rotation of the pinion 61 with fewer teeth to the low-speed rotation of the helical gear 62 with more teeth. Therefore, the helical gear 62 rotates at a lower speed than the pinion 61.

[0148] The rotating shaft 53 containing the pinion 61 is made of metal, and the pinion 61 is in the shape of... Figure 1 as well as Figure 7 The shape is as shown. Specifically, around the pinion 61, helical teeth 61a are integrally provided, the axial length of which is slightly longer than the axial length of the helical gear 62. Thus, the helical teeth 61a reliably mesh with the helical gear 62.

[0149] The helical tooth 61a extends continuously in a helical shape along the axial direction of the pinion 61, and there is only one helical tooth 61a in the pinion 61. That is, the pinion 61 has "1" teeth. Furthermore, the helical tooth 61a is formed in a circular cross-sectional shape and enters (meets) into the meshing recess 62d of the helical gear 62.

[0150] The helical gear 62 forming the reduction mechanism 60 is made of plastic and is in the shape of... Figure 1 as well as Figure 6 The shape is as shown. Specifically, the helical gear 62 includes a gear body 62a formed in a generally disc shape, and the bottom end of the output shaft 63 is firmly fixed to the rotation center of the gear body 62a by pressing or the like. Thus, the output shaft 63 rotates together with the helical gear 62. Furthermore, at the rotation center of the gear body 62a and on the side of the second sensor substrate 13 ( Figure 1 The sensor magnet SM is fixed on the lower side.

[0151] On the radially outer side of the gear body 62a, there is a gear forming portion 62b formed in a generally cylindrical shape. In the gear forming portion 62b, a plurality of helical teeth 62c are arranged circumferentially. These helical teeth 62c are inclined at a predetermined angle relative to the axial direction of the pinion 61, thereby causing the helical gear 62 to rotate along with the rotation of the helical teeth 61a. Specifically, there are engagement recesses 62d between adjacent helical teeth 62c, into which the helical teeth 61a enter and engage. Furthermore, the engagement recesses 62d are also formed in a circular cross-sectional shape.

[0152] On both axial sides of the gear forming section 62b, a first surface SF1 and a second surface SF2 are respectively provided. Furthermore, as... Figure 1 as well as Figure 5 As shown, the first surface SF1 is disposed on the bottom wall 21 side of the gearbox 20, and the second surface SF2 is disposed on the bearing bracket 40 side. Furthermore, in the axial direction of the output shaft 63, the first surface SF1 faces the first support protrusion 21d, and the second surface SF2 faces the pair of second support protrusions 41b. Therefore, when a large external force is applied to the output shaft 63, tilting of the helical gear 62 is suppressed.

[0153] In addition, such as Figure 4 As shown, when no large external force is applied to the output shaft 63, a small gap δS1 is formed between the first surface SF1 and the first support protrusion 21d. On the other hand, when no large external force is applied to the output shaft 63, a small gap δS2 (δS1≒δS2) is formed between the second surface SF2 and a pair of second support protrusions 41b. Thus, during the "normal operation" of the motor with the reduction mechanism on the output shaft 63 when no large external force is applied to it, the helical gear 62 is in a non-contact state with both the gearbox 20 and the bearing support 40, allowing for smooth rotation.

[0154] Conversely, during "overload operation" of the motor with a reduction gear mechanism on the output shaft 63, due to the tilting of the helical gear 62c, the helical gear 62 tends to tilt relative to the axis of the output shaft 63. Therefore, corresponding to the rotation direction of the helical gear 62, the first surface SF1 contacts (see reference). Figure 5 (The dashed arrow) to the first support protrusion 21d, the second surface SF2 contacts (refer to) Figure 5 (The dashed arrow indicates the direction of the helical gear 62) to a pair of second support protrusions 41b. Thus, the helical gear 62 is supported by the first support protrusion 21d and the second support protrusion 41b, thereby preventing further tilting of the helical gear 62. Therefore, it prevents the deterioration of the meshing state between the helical gear 62 and the pinion 61, and prevents damage to the plastic helical gear 62 caused by being bitten by the metal pinion 61.

[0155] Here, the number of helical teeth 62c (meshing recesses 62d) provided on the helical gear 62 is "40". That is, in this embodiment, the reduction ratio of the reduction mechanism 60, which includes the pinion 61 and the helical gear 62, is "40".

[0156] [Supporting Components]

[0157] like Figure 1 , Figure 4 , Figures 6 to 8 As shown, the support member 70 housed in the support member housing 22a of the gearbox 20 is formed into a generally rectangular parallelepiped shape by injection molding of a resin material such as plastic. The support member 70 includes: a fixed body portion 71, fixed to the gearbox 20; a pair of surrounding wall portions 72 integrally provided on the fixed body portion 71, surrounding the pinion 61 together with the fixed body portion 71; and an annular wall portion 73 integrally provided on one side of the long side of these surrounding wall portions 72. Figure 7 as well as Figure 8 (on the right side), and it forms a roughly ring shape.

[0158] A female threaded portion 71a is provided on the fixed body portion 71. The female threaded portion 71a corresponds to the fixing portion in this invention and is provided at the center of the support member 70 in the long side direction of the pinion 61. Moreover, the female threaded portion 71a is arranged on the side opposite to the pinion 61 side (back side) of the fixed body portion 71. Furthermore, a fixing screw SC1 is tightened in the female threaded portion 71a to fix the support member 70 to the gearbox 20.

[0159] Furthermore, on one side of the fixed body 71 in the long side direction ( Figure 7 as well as Figure 8 On the right side), a pair of support member inclined surfaces 71b are provided. These support member inclined surfaces 71b are connected to a pair of housing inclined surfaces 22c provided on the gearbox 20 (see reference). Figure 2 as well as Figure 9 (These are placed opposite each other.) Here, as... Figure 9 As shown, with the inclined surface 71b of the support member facing the inclined surface 22c of the housing, a space SP is formed between the front end of the support member 70 in the insertion direction and the bottom of the support member receiving portion 22a. This allows the pair of inclined surfaces 71b of the support member to be aligned with the pair of inclined surfaces 22c of the housing without wobbling, improving the positioning accuracy of the support member 70 relative to the gearbox 20.

[0160] like Figure 1 , Figure 4 , Figure 6 as well as Figure 10As shown, with the support member 70 assembled into the gearbox 20, the fixed body portion 71 forming the support member 70 is located on the opposite side of the pinion 61 and the helical gear 62 in the gearbox 20. Furthermore, a small gap (clearance) δS3 is formed between the pinion 61 and the fixed body portion 71. Here, the small gap δS3 is approximately the same size as the small gap δS1 between the first surface SF1 and the first support protrusion 21d, and the small gap δS2 between the second surface SF2 and a pair of second support protrusions 41b (δS1≒δS2≒δS3).

[0161] Thus, during the "normal operation" of the motor 10 with the reduction gear mechanism on the output shaft 63 without a large external force being applied, no load that would bend the pinion 61 is applied from the helical gear 62 to the pinion 61, so the pinion 61 can rotate smoothly relative to the support member 70 in a non-contact state.

[0162] Furthermore, the boss portion 21a supporting the output shaft 63 and the support member receiving portion 22a supporting the support member 70 are respectively provided in the aluminum gearbox 20, which is formed with high precision. Therefore, the positions of the output shaft 63 and the support member 70 can be arranged with high precision relative to each other. Thus, the pinion 61 can rotate smoothly relative to the support member 70 in a non-contact state, and the tiny gap δS3 between the pinion 61 and the fixed body portion 71 can be filled.

[0163] On the other hand, during "overload operation" of the motor 10 with a reduction gear on the output shaft 63, the helical gear 62c tilts, causing it to tilt relative to the axis of the output shaft 63. Consequently, a large lateral force is applied to the pinion 61 from its radially outer side. Therefore, although the pinion 61 is made of metal, the portion where it is located is particularly thin, resulting in weak resistance to lateral loads. As a result, the pinion 61 is radially pressed and bent by the helical gear 62.

[0164] At this time, the approximately central portion of the long side of the pinion 61 is pressed by the helical gear 62. Therefore, the approximately central portion of the long side of the pinion 61 contacts the fixed body portion 71. Since the approximately central portion of the long side of the pinion 61 is supported by the fixed body portion 71, further bending of the pinion 61 can be suppressed, and even the meshing state of the pinion 61 and the helical gear 62 can be maintained. Here, the support member 70 corresponds to the meshing retention member in this invention.

[0165] Furthermore, as the pinion 61 bends, the approximately central portion along the long side of the fixing body 71 is pressed down. However, the approximately central portion along the long side of the fixing body 71 is the least likely to wobble part, which is fixed to the gearbox 20 by the fixing screw SC1. Therefore, even when the pinion 61 bends repeatedly, the support member 70 can support the pinion 61 relative to the gearbox 20 without wobbling. Thus, premature damage to the support member 70 is effectively suppressed.

[0166] Furthermore, the minute gap δS3 between the pinion 61 and the fixed body 71 is set to a gap size that prevents the pinion 61 from disengaging from the helical gear 62. Furthermore, as... Figure 4 as well as Figure 10 As shown, in this embodiment, the fixing body portion 71 is provided over approximately the entire area along the long side of the pinion 61. However, as has been determined above, during "overload operation" of the motor 10 with the reduction mechanism, approximately the central portion along the long side of the pinion 61 will bend. Therefore, it is sufficient to simply place the fixing body portion 71 of the support member 70 at least at the central portion along the long side of the pinion 61. Specifically, it is also possible to delete... Figure 10 The shadow line portion enclosed by the two chain lines. At this time, it is possible to achieve weight reduction of the support member 70 and improve the forming accuracy of the support member 70 by reducing the wall thickness of the support member 70.

[0167] Moreover, such as Figure 11 As shown, a pair of surrounding wall portions 72 extend from the fixed body portion 71 toward the helical gear 62, and a small gap δS4 is formed between the front end sides of these surrounding wall portions 72 and the helical gear 62. These surrounding wall portions 72 are provided on both sides of the support member 70 in the rotation direction of the helical gear 62, corresponding to the second grease leakage prevention wall in the present invention. Furthermore, on the front end sides of the pair of surrounding wall portions 72, inclined surfaces 72a are respectively provided in a manner inclined toward the circumference of the helical gear 62, and these inclined surfaces 72a extend along the circumference of the helical gear 62 in a manner that follows the outer circumferential shape of the helical gear 62. Therefore, the small gap δS4 formed between the pair of inclined surfaces 72a and the helical gear 62 can be filled.

[0168] Here, as Figure 11 As shown, a small gap δS4 is formed between the pair of surrounding wall portions 72 and the helical gear 62. Therefore, when the helical gear 62 rotates in one direction, the grease (not shown) applied to the meshing portion of the pinion 61 and the helical gear 62 is prevented from leaking out to the outside of the surrounding wall portion 72, as indicated by the solid × arrow. On the other hand, when the helical gear 62 rotates in the other direction, the grease applied to the meshing portion of the pinion 61 and the helical gear 62 is also prevented from leaking out to the outside of the surrounding wall portion 72, as indicated by the dashed × arrow.

[0169] Furthermore, the minute gap δS4 is approximately the same size as the minute gap δS1 between the first surface SF1 and the first support protrusion 21d, the minute gap δS2 between the second surface SF2 and a pair of second support protrusions 41b, and the minute gap δS3 between the pinion 61 and the fixed body portion 71 (δS1≒δS2≒δS3≒δS4). Moreover, either of the pair of surrounding wall portions 72 can be removed, and at least one side of the support member 70 in the rotational direction of the helical gear 62 can be provided. In this case, grease leakage to the outside of the surrounding wall portion 72 can also be suppressed by the single surrounding wall portion 72.

[0170] like Figure 7 as well as Figure 8 As shown, the annular wall portion 73 is provided on one side of the support member 70 along the long side direction of the pinion 61. Figure 7 as well as Figure 8 On the right side), a pinion insertion hole 73a is provided approximately at the center of the annular wall portion 73. The pinion 61 rotates freely into the pinion insertion hole 73a in a non-contact state, and a small gap δS5 is formed between the pinion 61 and the pinion insertion hole 73a (see reference). Figure 8 ).

[0171] In addition, the minute gap δS5 and the minute gap δS3 between the pinion 61 and the fixed body 71 have the same gap size (δS3=δS5).

[0172] Thus, a tiny gap δS5 is formed between the pinion 61 and the pinion insertion hole 73a, thereby, as Figure 10 As shown, when the pinion 61 rotates in one direction, the grease (not shown) that is about to move as indicated by the solid arrow passes over the annular wall portion 73 and leaks to the outside of the annular wall portion 73 (refer to the solid × arrow). Furthermore, the grease that is partially caught by the annular wall portion 73 when the pinion 61 rotates in one direction returns towards the center of the long side of the pinion 61 as indicated by the dashed ○ arrow when the pinion 61 rotates in the other direction. Additionally, the annular wall portion 73 corresponds to the first grease leakage prevention wall in this invention.

[0173] In this embodiment, the motor 10 with a reduction gear is used as the drive source for the windshield wiper assembly. Therefore, when the wiper component (not shown) is oscillated, the pinion 61 and the helical gear 62 rotate in opposite directions at predetermined cycles. Thus, as... Figure 10 As shown, through repeated rotation in one direction (forward) and the other direction (reverse) of the pinion 61 and helical gear 62, the grease reciprocates along the axial direction of the pinion 61 on the inner side of the support member 70. That is, the grease can be retained in the meshing part of the pinion 61 and the helical gear 62 for a long time.

[0174] Furthermore, with the support member 70 housed in the support member housing portion 22a and a pair of support member side inclined surfaces 71b respectively facing a pair of housing side inclined surfaces 22c, the annular wall portion 73 enters into the opening of the bearing member housing portion 21c provided in the gearbox 20 (see reference). Figure 1 , Figure 4 as well as Figure 10 This can suppress the shaking of the support member 70 inside the gearbox 20.

[0175] As detailed above, according to this embodiment, a support member 70 is provided on the opposite side of the pinion 61 and the helical gear 62 in the gearbox 20 to maintain the meshing of the pinion 61 and the helical gear 62. Therefore, even when a large external force is applied to the output shaft 63, the meshing of the gears (the meshing of the pinion 61 and the helical gear 62) can be prevented from disengaging.

[0176] Therefore, damage to the pinion 61 and helical gear 62 (reduction mechanism 60) can be prevented for a long time, and even the lifespan of the motor 10 with the reduction mechanism can be extended. In other words, in this embodiment, by extending the lifespan of the motor 10 with the reduction mechanism, energy consumption in manufacturing the motor 10 with the reduction mechanism can be saved, and even the Sustainable Development Goals (SDGs) set by the United Nations can be achieved, especially Goal 7 (ensuring access to clean energy for all) and Goal 13 (taking concrete strategies to address climate change).

[0177] Furthermore, according to this embodiment, a small gap δS3 is provided between the pinion 61 and the fixed body portion 71 of the support member 70. Therefore, during the "normal operation" of the motor 10 with a reduction gear mechanism on the output shaft 63 without a large external force being applied, the pinion 61 can rotate smoothly relative to the support member 70 in a non-contact state. As a result, the generation of abnormal noise from the motor 10 with the reduction gear mechanism can be effectively suppressed, making it suitable for vehicles requiring quietness, such as electric vehicles.

[0178] Furthermore, according to this embodiment, the gearbox 20 includes a boss portion 21a supporting the output shaft 63 and a support member receiving portion 22a supporting the support member 70, thus enabling the output shaft 63 and the support member 70 to be positioned relative to each other with good precision. Therefore, the pinion 61 can rotate smoothly relative to the support member 70 in a non-contact state, and the tiny gap δS3 between the pinion 61 and the fixed body portion 71 can be filled, thereby preventing the motor 10 with the reduction mechanism from becoming unnecessarily large.

[0179] Furthermore, according to this embodiment, the support member 70 and the support member receiving portion 22a each include a pair of support member-side inclined surfaces 71b and a pair of housing-side inclined surfaces 22c, which position the support member 70 relative to the support member receiving portion 22a. Therefore, when the support member 70 is installed in the support member receiving portion 22a, the pair of support member-side inclined surfaces 71b collide with the pair of housing-side inclined surfaces 22c, thereby enabling the support member 70 to be positioned (centered) at a predetermined position in the support member receiving portion 22a. Consequently, the motor 10 with a reduction gear can be easily assembled.

[0180] Furthermore, according to this embodiment, the rotating shaft 53 and the output shaft 63 are arranged parallel to each other, the pinion 61 has a helical tooth 61a, and the helical gear 62 includes a helical tooth 62c that meshes with the helical tooth 61a. This allows the reduction mechanism 60 to be compact while achieving a large reduction ratio. Consequently, the motor 10 with the reduction mechanism can be miniaturized, making it easily applicable to small vehicles such as light automobiles.

[0181] Furthermore, according to this embodiment, the support member 70 may be disposed at least at the center of the long side of the pinion 61. That is, as... Figure 10 As shown, the shadow line portion enclosed by the two-point chain line can also be deleted. In this case, the support member 70 can be made lighter, and the wall thickness of the support member 70 can be reduced, thereby improving the molding accuracy of the support member 70 (injection molded article).

[0182] Furthermore, according to this embodiment, a female threaded portion 71a for fixing the support member 70 to the gearbox 20 is provided at the center of the support member 70 along the long side direction of the pinion 61. Therefore, when the pinion 61 bends, the least wobbly part of the fixing body 71 is pressed down, and even when the pinion 61 bends repeatedly, the support member 70 can support the pinion 61 relative to the gearbox 20 without wobbling. Thus, premature damage to the support member 70 can be prevented.

[0183] Furthermore, according to this embodiment, on one side of the support member 70 in the long side direction of the pinion 61 ( Figure 7 as well as Figure 8 On the right side, an annular wall portion 73 is provided, which prevents leakage of grease applied between the pinion 61 and the helical gear 62. Therefore, as Figure 10As shown, when the pinion 61 rotates in one direction, it can prevent the grease that is about to move as indicated by the solid arrow from leaking out of the annular wall 73. Therefore, the grease can be retained at the meshing part of the pinion 61 and the helical gear 62 for a long time, and even more so, the motor 10 with the reduction mechanism can operate smoothly for a long time.

[0184] Furthermore, according to this embodiment, a pair of surrounding wall portions 72 are provided on both sides of the support member 70 in the rotational direction of the helical gear 62. These surrounding wall portions 72 prevent leakage of the lubricating grease applied between the pinion 61 and the helical gear 62. Therefore, as... Figure 11 As shown, when the helical gear 62 rotates in one direction and in the other direction, the leakage of grease applied to the meshing portion of the pinion 61 and the helical gear 62 into the exterior of the surrounding wall 72 can be prevented. As a result, the motor 10 with the reduction gear mechanism can operate smoothly for a long time.

[0185] Furthermore, according to this embodiment, the gearbox 20 includes a first support protrusion 21d and a second support protrusion 41b, which suppress the tilting of the helical gear 62 relative to the gearbox 20. Therefore, when a large external force is applied to the output shaft 63, the tilting of the helical gear 62 can be suppressed, and even premature damage to the plastic helical gear 62 can be prevented, thereby extending the lifespan of the motor 10 with the reduction mechanism.

[0186] [Implementation Method 2]

[0187] Next, Embodiment 2 of the present invention will be described in detail using the accompanying drawings. Furthermore, parts having the same function as those in Embodiment 1 will be labeled with the same symbols, and their detailed descriptions will be omitted.

[0188] Figure 12 A perspective view illustrating embodiment 2 (bearing bracket) is shown.

[0189] like Figure 12 As shown, the bearing bracket 80 of Embodiment 2 and the bearing bracket 40 of Embodiment 1 (see reference) Figure 3 In contrast, the difference lies in that an annular platform 81 is provided around the insertion hole 41d of the support body 41 and on the side of the positioning protrusion 41a. Moreover, the difference is that a pair of second support protrusions (tilt suppression portions) 82 are extended to connect them to the annular platform 81.

[0190] The annular platform 81 is in the state where the motor 10 with the reduction gear is assembled (see reference). Figure 1 Below, on the other side in the direction of the long side of the support member 70 (enclosing wall portion 72) Figure 1The portion facing the lower side. Therefore, in the annular platform portion 81, it also faces the annular wall portion 73 of the support member 70 (see reference). Figure 7 as well as Figure 8 Similarly, it can prevent grease from leaking out of the annular platform 81 to the outside of the annular platform 81.

[0191] In Embodiment 2, as described above, the same effects as in Embodiment 1 can be achieved. Furthermore, in Embodiment 2, since the bearing support 80 has an annular platform 81, grease can be prevented from reaching the brushless motor 50. Therefore, it is possible to prevent leaked grease from adversely affecting the operation of the brushless motor 50. Moreover, by extending a pair of second support protrusions 82 to connect them to the annular platform 81, tilting of the helical gear 62 can be further suppressed.

[0192] [Implementation Method 3]

[0193] Next, Embodiment 3 of the present invention will be described in detail using the accompanying drawings. Furthermore, parts having the same function as those in Embodiment 1 will be labeled with the same symbols, and their detailed descriptions will be omitted.

[0194] Figure 13 A perspective view illustrating embodiment 3 (support member) is shown.

[0195] like Figure 13 As shown, the support member 90 of Embodiment 3 and the support member 70 of Embodiment 1 (see reference) Figure 7 as well as Figure 8 Compared to the previous one, the difference lies in the fact that, on the long side of the pinion 61, on the other side of the support member 90 (equivalent to...) Figure 7 as well as Figure 8 On the right side, another annular wall portion (first grease leakage prevention wall) 91 is also provided. In addition, the other annular wall portion 91 is also provided with the same pinion insertion hole 73a as the annular wall portion 73. Furthermore, the other annular wall portion 91 faces the annular wall portion 73 in the direction of the long side of the pair of surrounding wall portions 72.

[0196] In Embodiment 3, as described above, the same effects as in Embodiment 1 can be achieved. Furthermore, in Embodiment 3, since another annular wall portion 91 is also provided on the other side of the support member 70 (the brushless motor 50 side), similar to Embodiment 2, grease can be prevented from reaching the brushless motor 50. Therefore, it is possible to prevent leaked grease from adversely affecting the operation of the brushless motor 50.

[0197] Of course, the present invention is not limited to the embodiments described, and various modifications can be made without departing from its spirit. For example, the embodiments shown illustrate the use of a motor 10 with a reduction mechanism as a drive source for a windshield wiper unit mounted in a vehicle, but the present invention is not limited thereto and can also be applied to other drive sources such as power window units or sunroof units.

[0198] Furthermore, the embodiments described show a motor 10 with a reduction mechanism including a brushless motor 50, but the present invention is not limited thereto, and a brushed motor may also be used as the motor unit.

[0199] In addition, as long as the present invention can be achieved, the material, shape, size, quantity, and placement of each component in each embodiment are arbitrary and not limited to each embodiment.

Claims

1. A motor with a reduction gear, comprising: The motor section has a rotating shaft; as well as The speed reduction mechanism reduces the rotation of the rotating shaft. The motor with a speed reduction mechanism has: The first gear is integrally rotatable on the rotating shaft; The second gear meshes with the first gear and rotates at a lower speed than the first gear. The output shaft is located at the rotation center of the second gear; and The gearbox includes a bottom wall portion and side wall portions integrally formed around the bottom wall portion, and rotatably houses the first gear and the second gear. On the opposite side of the meshing portion of the first gear and the second gear in the gearbox, a meshing retaining member is provided to maintain the meshing of the first gear and the second gear. The engagement retaining member includes a fixed body portion and a female threaded portion. The fixed body portion is fixed to the gearbox, and the female threaded portion is disposed on the side of the fixed body portion opposite to the first gear side. The side wall of the gearbox is provided with a meshing and retaining member support, and the fixed body is fixed to the meshing and retaining member support. The retaining member support portion is provided with a single screw hole. A fixing screw for fixing the fixing body part to the retaining member support part is inserted into the screw hole. The fixing screw is tightened to the female threaded portion. When the first gear is bent by the pressure of the second gear, the first gear can contact the fixed body part.

2. The motor with a reduction gear according to claim 1, wherein... The gearbox includes: An output shaft support section supports the output shaft.

3. The motor with a reduction gear according to claim 2, wherein... The bite retention member and the bite retention member support each include a tapered surface, which positions the bite retention member relative to the bite retention member support.

4. The motor with a reduction gear according to claim 1, wherein... The rotating shaft and the output shaft are arranged parallel to each other. The first gear is a small gear with one tooth. The second gear is a helical gear that includes helical teeth for meshing with the first gear.

5. The motor with a reduction gear according to claim 4, wherein... The engagement retaining member is disposed at least at the center of the long side of the pinion.

6. The motor with a reduction gear according to claim 5, wherein... A fixing part for fixing the engagement retaining member to the gearbox is provided at the center of the engagement retaining member in the long side direction of the pinion.

7. The motor with a reduction gear according to claim 4, wherein... At least one side of the engagement retaining member in the long side direction of the pinion is provided with a first grease leakage prevention wall, which prevents leakage of grease applied between the pinion and the helical gear.

8. The motor with a reduction gear according to claim 4, wherein... At least one side of the engagement retaining member in the rotational direction of the helical gear is provided with a second grease leakage prevention wall, which prevents leakage of grease applied between the pinion and the helical gear.

9. The motor with a reduction gear according to claim 1, wherein... The gearbox includes a tilt-suppressing part that suppresses the second gear from tilting relative to the gearbox.

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