JPWO2014049682A1 - Deceleration mechanism - Google Patents

Abstract

Provided is a reduction mechanism that is lighter and more compact. The speed reduction mechanism 20 constitutes a first sun gear 22 and a first pinion gear 24 that meshes with the first sun gear 22, a second sun gear 23, and a second pinion gear 25 that meshes with the second sun gear 23. A second gear mechanism 21b and a planetary carrier 26 that rotatably supports each of the first and second pinion gears 24 and 25 and that can input and output rotational power to the first sun gear 22 and the second sun gear 23 are provided. Yes. The reduction ratio is shared by the first gear mechanism 21a and the second gear mechanism 21b.

Description

  The present invention relates to a speed reduction mechanism, and more particularly to a speed reduction mechanism preferably used on a power drive transmission path.

  Due to recent automobile circumstances, as an environmental countermeasure, while increasing efficiency (low fuel consumption), there is a tendency to improve merchantability (comfort and comfort by expanding boarding space). Therefore, it is essential to reduce the weight and size of the powertrain that is the driving force of the vehicle.

  By the way, a planetary gear mechanism is employed when a reduction mechanism is used in a driving force distribution device for four-wheel drive. As an example of this, there is a transfer device having, for example, a planetary gear mechanism (for example, see Patent Document 1).

Utility Model Registration No. 2604891

  The planetary gear mechanism of this type of transfer device performs speed reduction by engaging an internal gear (internal gear) with two pairs of large and small gears. This planetary gear mechanism is a structure advantageous for the axial space as a speed reduction mechanism, but the radial direction is disadvantageous in terms of space. That is, as the speed reduction ratio increases, the number of teeth of the internal gear increases, and the diameter of the internal gear increases. As a result, not only the weight but also the tendency to increase becomes remarkable.

  This leads to an increase in the indoor protrusion protruding on the center floor of the vehicle and a reduction in the boarding space, thus reducing the merchantability of the vehicle.

  Accordingly, an object of the present invention is to provide a speed reduction mechanism that is reduced in weight and size.

[1] The present invention provides a first gear mechanism that constitutes a first sun gear and a first pinion gear that meshes with the first sun gear, a second sun gear, and a second gear that constitutes a second pinion gear that meshes with the second sun gear. And a planetary carrier capable of rotatably supporting each of the first and second pinion gears and capable of inputting and outputting rotational power to the first sun gear and the second sun gear, and the first gear mechanism, The speed reduction mechanism has a configuration in which a reduction ratio is shared by the second gear mechanism.

[2] In the invention described in [1], the first sun gear is fixed to a casing that houses the first gear mechanism and the second gear mechanism in a state of being separated from the planetary carrier, The second sun gear is fixed to the planetary carrier so as to be relatively rotatable.

[3] In the invention described in [1] or [2], the planetary carrier includes a pinion support portion that rotatably supports the first pinion gear and the second pinion gear via a pinion shaft. It is characterized by becoming.

[4] In the invention described in [3] above, the pinion support portion supports the pinion shaft via a bearing.

[5] In the invention described in [3] or [4], one of the first pinion gear and the second pinion gear is integrally formed at one end of the pinion shaft, and the second pinion gear or the first pinion gear is formed. The other pinion gear is splined to the other end of the pinion shaft.

[6] In the invention described in [1], a speed change mechanism that switches between a high speed stage and a low speed stage is provided so as to be connectable to the second gear mechanism.

[7] In the invention described in [2] above, an oil reservoir for storing oil supplied to the first sun gear is provided on a wall surface of the casing facing the first sun gear. And

[8] In the invention according to any one of [3] to [5], the pinion support portion is formed with an oil hole that guides oil to the pinion shaft.

  According to the present invention, it is possible to reduce the weight and size of the speed reduction mechanism.

It is a principal part cross-sectional schematic diagram for demonstrating the transfer which has a reduction mechanism which concerns on typical embodiment of this invention. It is explanatory drawing which shows operation | movement of the deceleration mechanism in a two-wheel high-speed drive state with a skeleton. It is a skeleton figure for demonstrating operation | movement of the deceleration mechanism in a four-wheel high-speed drive state. It is a skeleton figure for demonstrating operation | movement of the deceleration mechanism in a four-wheel low speed drive state. It is a principal part cross-sectional schematic diagram for demonstrating the oil lubrication path | route of the speed reduction mechanism which concerns on embodiment.

  Preferred embodiments of the present invention will be specifically described below with reference to the accompanying drawings.

(Overall configuration of transfer)
In FIG. 1, reference numeral 1 indicating the whole schematically shows a main part of a typical transfer for a four-wheel drive vehicle according to this embodiment. The transfer 1 according to the illustrated example is applied to, for example, a four-wheel drive vehicle based on an FR (front engine, rear drive) system.

  As shown in FIG. 1, the transfer 1 has a casing 2 that houses components. An input shaft 3 for inputting rotational power from an engine (not shown) is rotatably supported by a front portion of the casing 2 via a ball bearing 4 with a seal. An oil seal 5 is disposed in an annular space formed by the ball bearing 4 with seal, the outer peripheral surface of the input shaft 3, and the casing 2.

  As shown in FIGS. 1 and 2, a rear wheel output shaft 6 that is a main output shaft disposed coaxially in the casing 2 is directly connected to the input shaft 3. The rear wheel output shaft 6 is supported in the input shaft 3 through bearings 7 and 8 so as to be relatively rotatable. A front wheel output shaft (not shown) serving as a sub output shaft for the rear wheel output shaft 6 is provided at a portion parallel to the rear wheel output shaft 6.

  The rear wheel output shaft 6 is provided with a drive sprocket 9 coaxially through a bearing 13 as shown in FIG. A driven sprocket (not shown) for the drive sprocket 9 is provided on the same axis as the front wheel output shaft. An annular front wheel drive chain (not shown) is wound around the drive sprocket 9 and the driven sprocket.

  As shown in FIGS. 1 and 2, the input shaft 3 is coaxially disposed with a speed reduction mechanism 20 that decelerates the rotational power input from the input shaft 3 and outputs it to the rear wheel output shaft 6. An HL switch for switching between high speed H and low speed L in the speed reduction mechanism 20 between the lock gear 10 splined to the input shaft 3 and the hub 11 formed integrally with the rear wheel output shaft 6. The sleeve 12 for use as a transmission mechanism is slidably disposed. In FIG. 1, the sleeve 12 shows a four-wheel high speed drive state, and in FIG. 2, the sleeve 12 shows a two-wheel high speed drive state.

  The hub 11 of the rear wheel output shaft 6 and the hub 9a of the drive sprocket 9 are driven by two-wheel drive (hereinafter referred to as “2WD”) or 4 as shown in FIG. A 2WD-4WD switching sleeve 14 for switching to wheel drive (hereinafter referred to as “4WD”) is provided to be slidable. In FIG. 2, the sleeve 14 shows a two-wheel high-speed drive state.

(Configuration of deceleration mechanism)
The most basic configuration in this embodiment is the speed reduction mechanism 20. As shown in FIGS. 1 and 2, the speed reduction mechanism 20 includes a planetary gear mechanism 21 having a double sun gear structure that does not have a ring gear that meshes with a pinion gear. The planetary gear mechanism 21 includes a first gear mechanism 21a and a second gear mechanism 21b on the same axis, and the first gear mechanism 21a and the second gear mechanism 21b share a reduction ratio. The reduction ratio of the reduction mechanism 20 is ensured.

  As shown in FIGS. 1 and 2, the first gear mechanism 21 a constitutes two rotational elements, a first sun gear 22 and a first pinion gear 24 that meshes with the first sun gear 22. One second gear mechanism 21 b constitutes two rotating elements, a second sun gear 23 and a second pinion gear 25 that meshes with the second sun gear 23. In the first gear mechanism 21 a and the second gear mechanism 21 b, a common planetary carrier 26 that can input and output rotational power to the first sun gear 22 and the second sun gear 23 is formed coaxially and integrally with the input shaft 3. Yes.

  As shown in FIGS. 1 and 2, a disk-shaped pinion support portion 26 a is formed on the outer peripheral surface of the planetary carrier 26 so as to protrude. A plurality of shaft holes 26b,..., 26b are formed through the pinion support portion 26a with the same phase difference. A pinion shaft 25a is rotatably supported in each of the shaft holes 26b via a bearing 27.

  As shown in FIGS. 1 and 2, a first pinion gear 24 is splined to one end of the pinion shaft 25a. A second pinion gear 25 is formed integrally with the other end of the pinion shaft 25a. Each of the first pinion gear 24 and the second pinion gear 25 is supported by the planetary carrier 26 so as to freely rotate and revolve.

  As shown in FIGS. 1 and 2, the first sun gear 22 is provided with an arm portion 22 a that is a fixing member extending toward the casing 2. The arm portion 22 a is fastened and fixed to the wall surface of the casing 2 by a bolt 15. The first sun gear 22 and the planetary carrier 26 are arranged in a state of being separated from each other by the arm portion 22a. One second sun gear 23 is supported by a planetary carrier 26 via a needle bearing 28 so as to be relatively rotatable.

  The rotational power of the planetary carrier 26 is input to the first sun gear 22 via the first pinion gear 24 as indicated by the solid line arrow in FIG. Since the first sun gear 22 is fixed to the casing 2, the rotational power input from the first sun gear 22 is output from the second sun gear 23 to the rear wheel output shaft 6 via the second pinion gear 25. It has become.

(Operation of deceleration mechanism in 2WDH state)
When the vehicle travels in a two-wheel high-speed drive (hereinafter referred to as “2WDH”) state, as shown in FIG. 2, the sleeve 14 for 2WD-4WD switching includes the hub 9a of the drive sprocket 9 and the rear wheel output shaft 6. The hub 11 is not connected. On the other hand, the HL switching sleeve 12 meshes with the lock gear 10 of the input shaft 3 and the hub 11 of the rear wheel output shaft 6, and the planetary gear formed integrally with the rear wheel output shaft 6 and the input shaft 3. The carrier 26 is connected.

  As shown in FIG. 2, since the sleeve 12 is detached from the second sun gear 23, the rotational power of the planetary carrier 26 idles the planetary gear mechanism 21 via the needle bearing 28. The output rotation of the planetary gear mechanism 21 is not transmitted to the rear wheel output shaft 6.

  Therefore, in the 2WDH state, the rotational power input from the input shaft 3 to the planetary carrier 26 is output to the rear wheel output shaft 6 via the lock gear 10, the sleeve 12, and the hub 11, as shown in FIG.

(Operation of deceleration mechanism in 4WDH state)
When the vehicle travels in a four-wheel high-speed drive (hereinafter referred to as “4WDH”) state, as shown in FIG. 3, the sleeve 14 for 2WD-4WD switching includes the hub 9 a of the drive sprocket 9 and the rear wheel output shaft. 6 and the drive sprocket 9 and the rear wheel output shaft 6 are connected.

  On the other hand, as shown in FIG. 3, the HL switching sleeve 12 remains engaged with the lock gear 10 of the input shaft 3 and the hub 11 of the rear wheel output shaft 6 as in the 2WDH state. Rotational power from the planetary gear mechanism 21 is not transmitted to the rear wheel output shaft 6.

  Accordingly, in the 4WDH state, the rotational power input from the input shaft 3 to the planetary carrier 26 is output to the rear wheel output shaft 6 via the lock gear 10, the sleeve 12, and the hub 11, as shown in FIG. 11, the sleeve 14, the hub 9a, the drive sprocket 9, the front wheel drive chain, and the driven sprocket, and output to the front wheel output shaft.

(Operation of deceleration mechanism in 4WDL state)
When the vehicle travels in a four-wheel low-speed drive (hereinafter referred to as “4WDL”) state, as shown in FIG. 4, the 2WD-4WD switching sleeve 14 is connected to the drive sprocket 9 in the same manner as in the 4WDH state. The rear wheel output shaft 6 is still connected. On the other hand, the HL switching sleeve 12 is detached from the lock gear 10 of the input shaft 3 to connect the second sun gear 23 and the hub 11 of the rear wheel output shaft 6.

  Therefore, the rotational power input to the planetary carrier 26 from the input shaft 3 is transmitted to the first sun gear 22 via the pinion shaft 25a and the first pinion gear 24, as indicated by the solid line arrows in FIG. Since the first sun gear 22 is fixed to the casing 2, the rotational power from the first sun gear 22 is transmitted to the second sun gear 23 via the pinion shaft 25 a and the second pinion gear 25.

  As shown in FIG. 4, the rotational power output from the second sun gear 23 is connected to the second sun gear 23 and the hub 11 of the rear wheel output shaft 6 by the sleeve 12. The rear wheel output shaft 6 is transmitted with the low-speed rotational driving force from the planetary gear mechanism 21 and the front wheel via the hub 11, the sleeve 14, the hub 9a, the driving sprocket 9, the front wheel driving chain, and the driven sprocket. It is transmitted to the output shaft.

  According to the reduction mechanism 20 configured as described above, the number of teeth of the first pinion gear 24 is ZC, the number of teeth of the first sun gear 22 is ZD, the number of teeth of the second sun gear 23 is ZA, and the second pinion gear 25 When the number of teeth is ZB, the gear ratio iO of the speed reduction mechanism 20 is expressed by the following equation (1). When the rotational speed of the rear wheel output shaft 6 is the output rotational speed ωA of the speed reduction mechanism 20 and the rotational speed of the input shaft 3 is the input rotational speed ωS of the speed reduction mechanism 20, the output rotational speed ωA is relative to the input rotational speed ωS. The speed is reduced according to the relationship of the following equation (2).

iO = (ZB / ZA) × (ZD / ZC) (1)
ωA = (1-iO) × ωS (2)

Therefore, the low gear ratio iL of the speed reduction mechanism 20 is calculated based on the following equation (3).
iL = 1 / (1-iO) (3)

  As is apparent from the above formulas (1) to (3), the number of teeth ZC of the first pinion gear 24, the number of teeth ZD of the first sun gear 22, the number of teeth ZA of the second sun gear 23, and the number of teeth of the second pinion gear 25 By appropriately selecting ZB, the low gear ratio iL of the speed reduction mechanism 20 can be set to a required value.

  The low gear ratio iL is not particularly limited, but is set to about 2.717, for example. Thus, when the vehicle travels in the 4WDL state, the rotational power of the rear wheel output shaft 6 is decelerated to a value corresponding to the Low gear ratio iL of about 2.717. This reduced rotational power becomes the driving force for the rear wheel output shaft 6.

(Configuration of oil lubrication path)
An oil reservoir 16 for storing oil can be formed between the wall surface of the casing 2 and the arm portion 22a of the first sun gear 22 as shown in FIG. An annular space 17 formed by the arm portion 22a, the wall surface of the casing 2, the ball bearing 4 with seal, and the input shaft 3 serves as a first oil lubrication path that communicates with the oil reservoir 16 via the guide path 16a. Is formed.

  As shown in FIG. 5, the oil reservoir 16 is disposed on the downstream side of the oil garter 2 a provided in the upper part of the inner surface of the casing 2. For example, the oil garter 16 is subjected to the centrifugal force generated by the rotation of the speed reduction mechanism 20. The oil scraped up to 2 a is configured to be stored in the oil reservoir 16.

  The oil stored in the oil reservoir 16 is formed between the first sun gear 22, the first pinion gear 24, and the planetary carrier 26 via the space 17 from the guide path 16 a as indicated by the broken arrow in FIG. 5. Is supplied to the oil groove 17a. Since the 1st sun gear 22 fixed to the wall surface of the casing 2 can be comprised as an oil lubrication path | route, it is not necessary to provide a special component, without receiving the influence of centrifugal force.

  In addition, it is possible to form an oil lubrication path by using an open structure ball bearing instead of the ball bearing 4 with a seal, and supply the oil stored in the oil reservoir 16 to the oil seal 5. Can do.

  An oil hole 26c that can guide oil supplied from a hydraulic pump (not shown) to the bearing 27 can be formed in the pinion support portion 26a of the planetary carrier 26 as a second oil lubrication path. The oil hole 26 c communicates with an oil groove 6 c formed between the outer peripheral surface of the rear wheel output shaft 6 and the planetary carrier 26 through an oil passage 6 a and an oil hole 6 b formed in the rear wheel output shaft 6. doing.

  The oil supplied to the oil hole 26c through the oil passage 6a, the oil hole 6b, and the oil groove 6c is supplied to the bearing 27 as shown by the one-dot chain arrow in FIG. The oil supplied to the bearing 27 is supplied to an oil groove 6 d formed by the second pinion gear 25, the second sun gear 23, and the planetary carrier 26.

(Effect of embodiment)
According to the speed reduction mechanism 20 configured as described above, in addition to the above effects, the following effects can be obtained.

(1) Since the internal gear (ring gear) of the planetary gear mechanism 21 is eliminated, the outer diameter of the entire speed reduction mechanism 20 can be reduced. Accordingly, the weight of the speed reduction mechanism 20 can be reduced.
(2) Since it is possible to reduce the outer diameter of the entire speed reduction mechanism 20, it is possible to prevent interference with other parts such as a striking rod that is interlocked with a shift lever operated by a driver during a shift change. Can do.
(3) The reduction ratio can be shared by the first gear mechanism 21a and the second gear mechanism 21b that are arranged on the same axis with respect to the common planetary carrier 26. The required reduction ratio can be ensured without increasing the diameter.

[Modification]
As described above, the typical configuration example of the speed reduction mechanism 20 in the present invention has been described with the embodiment and the illustrated example. However, the embodiment and the illustrated example limit the invention according to the claims. is not. Various configurations are possible within the scope of the technical idea of the present invention, and the following modifications are also possible.

  In the embodiment and the illustrated example, the configuration in which the oil garter 2a that collects the oil scooped up by the centrifugal force generated by the rotation of the speed reduction mechanism 20 is illustrated, but the present invention is limited to this. However, instead of the oil garter 2a, it is possible to form a configuration for collecting oil in the arm portion 22a of the first sun gear 22 itself.

  For example, the arm portion 22a of the first sun gear 22 is formed in a lid shape, and the outer surface of the arm portion 22a protrudes outward from the oil supply hole and the peripheral edge of the oil supply hole. A concave oil introduction rib can be formed. With this configuration, the oil splashed by the rotation of the speed reduction mechanism 20 can be collected in the oil introduction rib, and the collected oil can be guided from the oil supply hole to the oil reservoir 16.

  In the above embodiment and the illustrated example, the first pinion gear 24 is splined to one end of the pinion shaft 25a, and the second pinion gear 25 is integrally formed with the other end of the pinion shaft 25a. Conversely, the first pinion gear 24 may be integrally formed at one end of the pinion shaft 25a, and the second pinion gear 25 may be splined to the other end of the pinion shaft 25a. The configuration may be such that each of the 24 and the second pinion gear 25 is spline-coupled.

  In the above embodiment and the illustrated example, the FR type four-wheel drive vehicle transfer has been described. However, the present invention is not limited to this, and for example, an FR type with a center differential is used. It can be effectively used for four-wheel drive vehicle transfer, FF type four-wheel drive vehicle transfer, and the like.

  In the above-described embodiments and illustrated examples, the case where the speed reduction mechanism of the present invention is applied to a transfer has been described. However, the present invention is not limited to this, and various types of power such as a differential, for example, may be used. The speed reduction mechanism 20 of the present invention can be effectively used on the drive transmission path.

  Needless to say, the present invention can be used for various devices that transmit torque between the input side and the output side, for example, working vehicles such as agricultural machines, construction civil engineering machines, and transporting machines, and four for rough terrain. The present invention can also be applied to various vehicles such as a wheeled vehicle (ATV), a railway, various industrial machines, machine tools, and the like, and the initial object of the present invention can be sufficiently achieved.

  As is clear from the above description, not all the combinations of features described in the above-described embodiments, modifications, and illustrated examples are necessarily essential to the means for solving the problems of the present invention. Of course, various configurations are possible within the scope of the technical idea of the present invention.

DESCRIPTION OF SYMBOLS 1 ... Transfer, 2 ... Casing, 2a ... Oil garter, 3 ... Input shaft, 4 ... Sealed ball bearing, 5 ... Oil seal, 6 ... Rear-wheel output shaft, 6a ... Oil path, 6b, 26c ... Oil hole, 6c , 6d, 17a ... oil groove, 7, 8, 13, 27 ... bearing, 9 ... drive sprocket, 9a, 11 ... hub, 10 ... lock gear, 12, 14 ... sleeve, 15 ... bolt, 16 ... oil reservoir, 16a DESCRIPTION OF SYMBOLS ... Guide path, 17 ... Space, 20 ... Deceleration mechanism, 21 ... Planetary gear mechanism, 21a ... First gear mechanism, 21b ... Second gear mechanism, 22 ... First sun gear, 22a ... Arm part, 23 ... Second sun gear, 24 ... 1st pinion gear, 25 ... 2nd pinion gear, 25a ... Pinion shaft, 26 ... Planetary carrier, 26a ... Pinion support part, 26b ... Shaft hole, 28 ... Needle bearing

Claims (8)

A first gear mechanism constituting a first sun gear and a first pinion gear meshing with the first sun gear;
A second gear mechanism constituting a second sun gear and a second pinion gear meshing with the second sun gear;
A planetary carrier capable of rotatably supporting each of the first and second pinion gears and capable of inputting and outputting rotational power to the first sun gear and the second sun gear;
With
A speed reduction mechanism having a configuration in which a reduction ratio is shared by the first gear mechanism and the second gear mechanism. The first sun gear is fixed to a casing that houses the first gear mechanism and the second gear mechanism in a state of being separated from the planetary carrier,
The speed reduction mechanism according to claim 1, wherein the second sun gear is fixed to the planetary carrier so as to be relatively rotatable.   The speed reduction mechanism according to claim 1 or 2, wherein the planetary carrier includes a pinion support portion that rotatably supports the first pinion gear and the second pinion gear via a pinion shaft.   The speed reduction mechanism according to claim 3, wherein the pinion support portion supports the pinion shaft via a bearing.   One of the first pinion gear or the second pinion gear is formed integrally with one end of the pinion shaft, and the other of the second pinion gear or the first pinion gear is splined to the other end of the pinion shaft. The speed reduction mechanism according to claim 3 or 4.   2. The speed reduction mechanism according to claim 1, wherein a speed change mechanism for switching between a high speed stage and a low speed stage is provided so as to be connectable to the second gear mechanism.   The speed reduction mechanism according to claim 2, wherein an oil reservoir for storing oil supplied to the first sun gear is provided on a wall surface of the casing facing the first sun gear.   The speed reduction mechanism according to claim 3, wherein an oil hole that guides oil to the pinion shaft is formed in the pinion support portion.

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