This non-provisional patent application claims priority under 35 U.S.C. ยง 119(a) from Patent Application No. 201710029027.7 filed in The People's Republic of China on Jan. 16, 2017.
The present invention relates to the field of vehicle doors, and in particular to a window drive apparatus including an electric motor and a gear train, and a vehicle door employing the window drive apparatus.
A vehicle door usually comprises an outer wall, an inner wall, a window glass and a window drive apparatus. The window glass is movably installed between the outer wall and the inner wall. The window drive apparatus is installed between the outer wall and the inner wall for lifting and lowering the window glass. The vehicle door has a limited thickness which requires the volume of the window drive apparatus is as small as possible. A traditional window drive apparatus has a reduction ratio of around 75 which is not big enough.
Thus, there is a desire for a window drive apparatus with an increased reduction ratio.
In one aspect, the present disclosure provides a window drive apparatus which includes an electric motor and a gear train. The gear train includes a first deceleration mechanism and a second deceleration mechanism. The first deceleration mechanism comprises a worm driven by the electric motor and a worm gear meshed with the worm. The second deceleration mechanism comprises a first driving gear and a second driving gear coaxially fixed and respectively located at opposite sides of the worm gear, a first driven gear meshed with the first driving gear and a second driven gear meshed with the second driving gear. The first driven gear and the second driven gear are coaxially fixed together.
Preferably, outer diameters of the first driving gear and the second driving gear are both less than that of the worm gear, and a receiving space is defined between the first driven gear and the second driven gear for receiving a radial external portion of the worm gear.
Preferably, a distance between two surfaces of the first driving gear and the second driving gear opposing from each other is equal to or slightly greater than a distance between two surfaces of the first driven gear and the second driven gear opposing from each other.
Preferably, the worm is coaxially fixed to a first rotation axle, the motor comprises an output shaft, the first rotation axle and the output shaft of the motor are separately formed and coaxially connected together, and the first rotation axle is supported by a bearing which is located between the worm and the electric motor.
In another aspect, the gear train further comprises an output wheel which is coaxially fixed with the first driven gear.
Preferably, the output wheel is positioned to the first driven gear via a positioning projection engaged in a positioning slot.
Preferably, a height of the gear train is substantially equal to a thickness of the motor.
Preferably, the electric motor is a single phase motor.
In another aspect, the present disclosure provides a vehicle door which includes an outer wall, an inner wall, a window glass and a window drive apparatus. The window glass and the window drive apparatus are installed in a space defined between the outer wall and the inner wall. The window drive apparatus includes an electric motor and a gear train. The gear train includes a first deceleration mechanism configured to decelerate an output speed of the electric motor and a second deceleration mechanism configured to decelerate an output speed of the first deceleration mechanism, the electric motor drives the window glass to move via the first and second deceleration mechanism.
Preferably, the gear train has a reduction ratio greater than 90.
Preferably, the electric motor is a single phase motor.
Preferably, the first deceleration mechanism comprises a worm driven by the electric motor and a worm gear meshed with the worm, and the second deceleration mechanism comprises a first driving gear, a second driving gear, a first driven gear meshed with the first driving gear and a second driven gear meshed with the second driving gear, the first driving gear and the second driving gear are coaxially fixed together and located at opposite sides of the worm gear, the first driven gear and the second driven gear are coaxially fixed together.
Preferably, outer diameters of the first driving gear and the second driving gear are both less than that of the worm gear, and a receiving space is defined between the first driven gear and the second driven gear for receiving a radial external portion of the worm gear.
Preferably, a distance between two surfaces of the first driving gear and the second driving gear opposing from each other is equal to or slightly greater than a distance between two surfaces of the first driven gear and the second driven gear opposing from each other.
Preferably, the gear train further comprises an output wheel which is coaxially fixed with the first driven gear.
Preferably, a height of the gear train is substantially equal to a thickness of the motor.
The gear train of the window drive apparatus of the present disclosure has two stages deceleration mechanism and thus has an increased reduction ratio.
Below, embodiments of the present invention will be described in greater detail with reference to the drawings. Elements of similar structures or functions are generally represented by like reference numerals for illustrative purposes throughout the figures. It should be noted that the figures are illustrative rather than limiting. The figures are not drawn to scale, do not illustrate every aspect of the described embodiments, and do not limit the scope of the present disclosure. Unless otherwise specified, all technical and scientific terms used in this disclosure have the ordinary meaning as commonly understood by people skilled in the art.
Refer to
Refer to
Refer to
Refer to
The worm 43 is coaxially fixed to a first rotation axle 16 and is rotatable together with the first rotation axle 16. In this embodiment, the first rotation axle 16 and an output shaft 15 of the motor 10 are separately formed and coaxially connected together. The worm 43 is fixedly mounted around the first rotation axle 16. Alternatively, the worm 43 may be integrally formed with the first rotation axle 16 or connected to the first rotation axle 16 through a connecting part. The first rotation axle 16 may be a part of the output shaft 15 of the motor 10. In all alternative embodiments, the worm 43 is rotatable with the output shaft 15 of the motor 10 coaxially and synchronously.
The worm gear 51 is mounted around the first mounting shaft 50 and is rotatable relative to the casing 33 of the gear train 30. The worm gear 51 is meshed with the worm 43, and the number of teeth of the worm gear 51 is greater than the number of the starts of the worm 43. The first driving gear 61 and the second driving gear 62 are mounted around the first mounting shaft 50 and respectively fixed to opposite axial sides of the worm gear 51, and are rotatable together with the worm gear 51. The outer diameters and teeth numbers of the first driving gear 61 and the second driving gear 62 are less than the outer diameter and the teeth number of the worm gear 51.
The first driven gear 71 and the second driven gear 72 are rotatably mounted in the gear train 30 through the second mounting shaft 81. The first driven gear 71 and the second driven gear 72 are coaxially fixed with each other and meshed with the first driving gear 61 and the second driving gear 62 respectively. The number of the teeth of the driven gear 71 is greater than that of the driving gear 61, and the number of the teeth of the driven gear 72 is greater than that of the driving gear 62. The output wheel 83 is mounted around the second mounting shaft 81 and coaxially fixed with the first driven gear 71 and the second driven gear 72. The outer diameter of the output wheel 83 is less than that of the first driven gear 71 and the second driven gear 72.
In this embodiment, the gear train 30 employs two stages deceleration mechanisms and thus has an increased reduction ratio. Preferably, the reduction ratio of the gear train 30 is bigger than 90. In this embodiment, the reduction ratio of the gear train 30 is in the range from 90 to 120.
Preferably, the electric motor 10 is a single phase motor which has the characteristics of low cost, small volume, light weight, low noise and high output speed. The single phase motor 30 cooperates with the gear train 30 with a high reduction ratio, which can meet the requirement of the window drive apparatus. In this embodiment, the single phase motor 10 is a single phase brushless direct current motor.
Preferably, the tooth pitch of the first driving gear 61 is equal to that of the second driving gear 62 and the tooth pitch of the first driven wheel 71 is equal to that of the second driven wheel 72. The tooth pitches of the driving gears 61, 62 and driven gears 71, 72 are all larger than that of the worm gear 51. Via using dual driving gears 61 and 62 and dual driven gears 71 and 72, the gear train 30 can realize dual side output, which can reduce the axial size (also known as the height of the gear train) of the gear train 30 but keep a high reduction ratio without increasing the thickness significantly.
Preferably, the outer diameter and the teeth number of the first driving gear 61 are equal to that of the second driving gear 62. The outer diameter and the teeth number of the first driven gear 71 are equal to that of the second driven gear 72. Thus, an symmetric structure is arranged at opposite sides of the worm gear 51 in order to keep the stability of transmission.
Preferably, the first driven gear 71 and the second driven gear 72 are symmetrically distributed at opposite sides of the worm gear 51. A space 74 is defined between the first driven gear 71 and the second driven gear 72 for receiving a radial external portion of the worm gear 51, in order to avoid mechanical interference between the driven gears 71, 72 and the worm gear 51.
Preferably, the first rotation axle 16 is supported by a bearing 18 located between the worm 43 and the motor 10, to increase the bearing capacity of the first rotational axle 16.
Preferably, the distance H3 (see
Refer to
Refer to
Therefore, the technical solutions of embodiments of the present invention have been clearly and completely described above. Apparently, the described embodiments are merely part of, rather than all of, the embodiments of the present invention. A person skilled in the art may make various combinations of technical features in the various embodiments to meet practical needs. Based on the described embodiments of the present invention, any other embodiment obtained by a person skilled in the art without paying creative efforts shall also fall within the scope of the present invention.
Number | Date | Country | Kind |
---|---|---|---|
2017 1002 9027.7 | Jan 2017 | CN | national |