RU2183565C2 - Transfer case - Google Patents

Abstract

FIELD: transport engineering. SUBSTANCE: proposed transfer case has housing, coaxial primary shaft and secondary shaft and countershaft parallel to primary and secondary shafts, differential coupled with secondary shaft, three-position clutch installed between pairs of low gears on secondary shaft hub, gearshift clutch with reverse gear installed on axis between secondary shaft and countershaft, two twin gearshift clutches, each consisting of one-way clutch members engaged with fork and four-position clutch installed on rim of secondary shaft to selectively engage countershaft gears with secondary shaft gears or with differential gears. EFFECT: reduced metal usage in transfer case, improved operating capabilities and increased efficiency. 3 dwg

Description

 The invention relates to transport engineering, to the transmission of transport vehicles.

 Known transmission units with a step change in gear ratios and torque distribution between output shafts containing gears, shafts, bearings, gear shifting devices used in domestic and foreign cars (Osepchugov V.V., Frumkin A.K. Automobile: Structural analysis, elements of calculation. - M.: Mechanical Engineering, 1989. - 304 p.).

 These units are structurally complex and metal-intensive.

 8-speed gearboxes (gearboxes) combined with a transfer case (RC) are used, for example, KAZ-4540 gearbox (see p. 63, Fig. 40). The basic 4-speed three-shaft gearbox is combined in one unit with a deceleration divider. Installing the front splitter reduced the unit’s metal consumption compared to units of the conventional layout, when a pair of gears is required for each gear, 8 forward gears are implemented by 10 gears and two reverse gears require three more gears. The gearbox is aggregated together with a differential single-stage transfer case (RC), in which three gears operate in the multiplier mode (see p. 74, Fig. 50). The unit as a whole contains 16 external gears, a symmetrical differential, four shift clutches and one differential lock clutch.

 This multi-stage transfer case (RTO) is also complex and metal-intensive, it has insufficient operational capabilities.

 The objective of the invention is to reduce the metal consumption of the unit and the expansion of its operational capabilities.

 The technical result is achieved by the fact that the gear is fixed on the input shaft, the gears of the gears on the intermediate shaft are installed freely, and the drive gear of this shaft is fixed and engaged with the gear freely installed on the output of the secondary shaft, on the wide crown of this gear there is a four-position switching clutch, under the clutch a narrow crown is fixed on the secondary shaft, next to it is a wide crown, which is connected by a tubular shaft to the differential gear.

 In FIG. 1 shows the kinematic diagram of an 8R4 MPK (8 forward gears and 4 reverse gears) with a symmetric differential and a four-position clutch for controlling this differential. Clutches A, B and C are shown in the neutral position, in fact, couplings A and B in this position are not fixed, but only pass it when shifting gears, clutch R in the left position is turned off.

 In FIG. Figure 2 shows a fragment of the kinematic differential circuit with a control clutch of a different switching order.

 Figure 3 presents the beam diagram with a table of positions of the clutch on different gears, the numbers of which (8-1) are indicated above the upper horizontal. Reverse gears are indicated below the lower horizontal (4R-1R). On the horizontal scales of the radiation diagram in a logarithmic form, the gear ratios of gear pairs and gears are presented. On the extreme horizontals, the gear ratios are reduced to the secondary shaft, and on the middle to the intermediate shaft. A vertical beam indicates a gear ratio of one. The tilt of the beam to the right characterizes the decelerating mode of operation of a pair of gears, the more the beam, the greater the gear ratio. The tilt of the beam to the left indicates the accelerating mode of operation of a pair of gears. The tilt of the beam of each pair of gears is constant on any part of the radiation diagram.

 Primary 2 and secondary 3 shafts are located in the bearings of the housing of the RTO 1 (see Fig. 1), the rear axle drive shaft (rear axle carts) 4 is aligned with it, the front axle drive shaft (front axle carts) is located parallel to the coaxial shafts. 5. Gear 6 is made in conjunction with the primary shaft 2 and engaged with a gear 7, which is freely mounted on the shaft 5. On the shaft 5, gears 8, 9 and 10 are freely mounted, which are engaged with gears 11, 12 and 13, respectively, freely mounted on the secondary shaft 3. The reverse gear 14 is located between gears 9 and 10, forms a block of gears with them, opposite gear 14 on the hub of clutch C of the secondary shaft 3, a driven reverse gear 15 is fixed, between gears 14 and 15 a separate reverse gear 16 with a shift clutch R is mounted on the axis. the shaft 3 is fixed to the differential crosspiece (carrier) 17 with the satellites 18. The satellites 18 are engaged with the gear 19, which is mounted on the rear axle drive shaft 4, they are also engaged with the gear 20, which is connected by a tubular shaft to the wide crown 21. Between the gear 13 and the crown 21 m in the secondary shaft 3 is loosely fitted gear 22 with a wide crown, this pinion gear 23 is engaged with the drive shaft 5. Between the broad rims 21 and pinion 22 on the output shaft 3 fixed narrow crown 24.

 The double shift clutch A consists of a coupling half 25 mounted on the gear ring 11 and the floor of the coupling 26 mounted on the gear ring 7 opposite the coupling half 25. Both coupling halves are interconnected by the shift fork 27. A similar double coupling B consists of a coupling half 28 mounted on the gear ring 12 , and the coupling half 29 mounted on the gear ring 8, the two coupling halves are interconnected by the shift fork 30. The four-position coupling D (31) is located on the gear ring 21 and the gear ring 22.

 Opposite unfolded half-couplings 25, 26 and 28, 29 of single-acting can be installed differently: half-coupling 25 - on the gear ring 6 of the input shaft 2, and half-coupling 28 - on the gear ring 11, the half-couplings interconnected with them should be installed opposite the first half-couplings: half-coupling 26 - on the ring gear 8, and the coupling half 29 - on the ring gear 9 with the corresponding lengthening of the rims.

 The crowns of the clutches D (31) and gears can also differ: wide crowns of gears and medium widths, the right crown of the coupling, narrow crowns of the left part of the coupling and crown 24, the distance between crown 24 and gear ring 22 is greater than the gap between crowns 21 and 24 (see Fig. .1 on the right); small gaps between the crown gear 24 and the gear crowns (see FIG. 2), the average width of the gear crowns 21, 24 and the clutch 31, the wide gear crown 22. On the tubular shaft of the differential gear 20 between the crown 21 and the housing, it is possible to install another narrow gear.

 The node for dividing the power flow of the Republic of Kazakhstan can be performed separately (see Fig. 2).

 The differential can be symmetrical, as in FIG. 1, or asymmetrical and distribute torque between bridges with 4x4 wheel arrangement, and between bridge trolleys with 8x8 wheel drive, etc., or between a bridge and a bridge trolley with 6x6 wheel drive .

The work of RTOs is as follows:
First gear
Clutches A and C are in the right position, and couplings B and R are in the left (see Fig. 3, the positions of the switching clutches in the table on the right above t. 1). The torque from the input shaft 2 is transmitted by a pair of gears 6-7, a coupling half 26, a pair of gears 8-11, a coupling half 28, a pair of gears 12-9 along the gear block, a pair of gears 10-13 along the coupling D to the secondary shaft 3. From the secondary shaft 3, the torque is supplied to the differential carrier 17 and the satellites 18 are distributed to the gears 19 and 20.

The coupling D (31) can provide four operating modes:
1. The coupling D (31) is in the extreme left position: the right crown of the coupling D is connected to the crown 24 of the secondary shaft 3, and the left crown is connected to the crown of the gear 22, the torque from the secondary shaft 3 is transmitted through a pair of gears 22-23 and shaft 5 on the front axle, in this position of the clutch D differential is disconnected and torque is not supplied to the rear axle (see figure 1). The transmission operates in front-wheel drive mode with a 4x2 wheel formula.

 2. We shift the coupling D one step to the right: the right crown of the coupling D connects the crowns 24 and 21, the differential is locked, the differential torque is transmitted to the rear axle, the left crown of the coupling D is engaged with the crown of the gear 22 and ensures the transmission of torque and to the front axle. The transmission operates in a locked mode with a 4x4 wheel arrangement.

 3. We shift the clutch D one more step to the right (see figure 1 to the right): the clutch D connects the crown 21 to the ring gear 22, while the clutch D is out of engagement with the crown 24 of the secondary shaft. The transmission operates in differential mode with a 4x4 wheel formula.

 4. We shift the clutch D to the extreme right position: the clutch D disengages from the ring gear 22 of the front axle drive, the left narrow crown of the clutch D engages the ring 24 of the secondary shaft, and the right ring of the clutch is engaged with the ring 21 of the differential gear 20, differential blocked because clutch D closed two differential links: carrier 17 and gear 20. The transmission operates in a rear-wheel drive vehicle with a 4x2 wheel arrangement.

 On the ray diagram (see Fig. 3) this transmission is represented by four rays: from t. 7 on the upper horizontal a gentle beam 6-7 to the right down to the middle horizontal, then the vertical beam 8-11 up to t. 5, then beam 12 -9 right down and a gentle beam 10-13 right up to t. 1.

Second gear
We switch the coupling B to the right position, the coupling half 28 is turned off, and the coupling half 29 is turned on, while turning off two pairs of gears: 8-11 and 12-9. The torque from the input shaft 2 is transmitted by a pair of gears 6-7, a coupling half 26, a hub and a ring gear 8, a coupling half 29, a tubular shaft of a gear unit and further, as in the previous gear.

 On the beam diagram, this transmission corresponds to two beams: from t.7 a gentle beam 6-7 to the right down, then a gentle beam 10-13 to the right up to t.2.

Third gear
We switch the couplings A and B to the left position, turn off the coupling halves 26 and 29, and turn on the coupling halves 25 and 28, instead of the pair of gears 6-7, turn on the pair 12-9. Torque is transmitted from the input shaft 2 by the coupling half 25, the crown and hub of the gear 11, the coupling half 28, a pair of gears 12-9 and further, as in previous gears. In this position, the clutch gears 7 and 8 rotate idle.

 Two rays belong to this transmission on the radiation diagram: from t.7, the middle ray is 12–9 down to the right, then a gentle ray 10–13 to t. 3.

Fourth gear
Return clutch B to the right position, as in second gear. The torque from the input shaft 2 is transmitted by the coupling half 25, a pair of gears 11-8, the coupling half 29 and further, as in previous gears.

 On the beam diagram, this transmission is represented by two beams: from t.7 a vertical beam 11-8 down, then a gentle beam 10-13 to the right up to t.4.

Fifth gear
We return the clutch A to the right position, as in the first and second gears, we switch the clutches B and C to the left position. The coupling halves 25 and 29 are turned off and the coupling halves 26 and 28 are turned on, clutch C connected gear 12 to the secondary shaft 3 instead of gear 13. The torque is transmitted from the input shaft 2 by a pair of gears 6-7, coupling half 26, a pair of gears 8-11, which Compared with the first gear, it works in a different direction, with a coupling half 28, a gear ring and a gear hub 12, a coupling C on the secondary shaft 3 and further, as in all gears.

 On the beam diagram, this transmission corresponds to two beams: from t.7 a gentle beam 6-7, then vertically up to t.5 beam 8-11.

Sixth gear
Switch clutch B to the right position. The torque from the input shaft 2 is transmitted by a pair of gears 6-7, a coupling half 26, a hub and a ring of gears 8, a coupling half 29, a pair of gears 9-12, which, in comparison with the first gear, works in the other direction, by the coupling C to the secondary shaft 3.

 In the beam diagram, this transmission is represented by two beams: a gentle beam 6-7 to the right downward and an accelerating beam 9-12 to the left up to point 6.

Seventh gear - direct
All couplings are in the left position. The torque from the input shaft 2 is transmitted by the coupling half 25, the crown and hub of the gear 11, the coupling half 28, the crown and hub of the gear 12, then by the coupling C to the secondary shaft 3.

 On the beam diagram, this transmission is represented by t.7 on the left on the upper horizontal.

Eighth gear - accelerating
Switch clutch B to the right position. Torque is transmitted from the input shaft 2 by the coupling half 25, a pair of gears 11-8, the coupling half 29 and further, as in the sixth gear.

 On the beam diagram, this transmission is represented by two beams: from t.7 vertically downward, ray 11-8, then ray 9-12 to the left, abruptly upward to t. 8.

 The reverse gears are engaged by moving the clutch R from the left to the right position, the clutch C must be in the neutral position, while a separate reverse gear 16 will engage with the driving gear 14 and the driven gear 15. The positions of the remaining couplings correspond to the positions of the four first forward gears (see figure 3, the lower and upper tables).

First Reverse - 1R
Clutches A, C and R are in the right position, and clutch B is in the left (see Fig. 3, the lower table on the right under t. 1R). The torque from the input shaft 2 to the gear block is transmitted, as in the first forward gear, from the gear block the torque is transmitted by a number of reverse gears 14-16-15 and through the coupling C to the secondary shaft 3, then to the differential and further, as on previous gears (see figure 1).

 Four rays correspond to this transmission on the radiation diagram: from point 7 on the upper horizontal a gentle beam 6-7 to the right down, then vertically upward the beam 8-11 to 5, then the beam 12-9 to the right down and the gentle beam 14-16 -15 also right down to t. 1R.

Second Reverse - 2R
All couplings in the right position, in comparison with the first reverse gear, turned off two pairs of gears: 8-11 and 12-9. The torque to the gear block is transmitted, as in the second forward gear, and from the block, as in the previous gear.

 Two rays belong to this transmission on the radiation diagram: a gentle beam 6–7 to the right downward and then a gentle beam 14–16–15 also to the right downward to point 2R.

Third Reverse - 3R
We switch couplings A and B to the left position. The torque to the gear block is transmitted, as in the third forward gear, then, as in the previous two gears.

 On the beam diagram, this transmission corresponds to two beams: from t.7, the middle ray is 12-9 to the right down, then the gentle beam 14-16-15 to the right down to t. 3R.

Fourth Reverse - 4R
Switch clutch B to the right position. The torque from the input shaft 2 is transmitted by the coupling half 25, a pair of gears 11-8, the coupling half 29, the gear block, a number of reverse gears 14-16-15, the coupling C to the secondary shaft 3 and further in accordance with the operating mode specified by the coupling D ( see figure 1).

 On the beam diagram, this transmission belongs to two beams: from t. 7 vertically down beam 11-8, then a gentle beam 14-16-15 right down to t. 4R (see figure 3).

With another design of the clutch 31 (D) and the rims of the gears 20 and 22 (see figure 2), a different procedure is implemented:
I - coupling 31 in the extreme left position: the left crown of the coupling is on the wide crown of the gear 22 on the left (see figure 2, the upper position of the coupling), the right crown of the coupling blocks the differential, because closes between itself a narrow crown 24 of the secondary shaft 3 and the differential carrier 17, as well as a narrow crown 21 of the differential gear 20. The transmission operates in a locked mode with a 4x4 wheel arrangement.

 II - we shift the coupling 31 one step to the right (see figure 2, the second position from above): the left crown of the coupling is located on the wide crown of the gear 22 to the right, the right crown of the coupling has disengaged from the narrow crown 24 of the secondary shaft 3 and is located on the crown 21 gears 20 differential - differential unlocked. The transmission operates in differential mode with a 4x4 wheel formula.

 III - we shift the coupling 31 one more step to the right (see figure 2, the second position from the bottom): the right crown of the coupling has disengaged from the crown 21 of the differential gear 20 — the differential is disconnected, the left crown of the coupling 31 closes the crown 24 of the secondary shaft 3 and a wide crown of the gear 22. The torque from the secondary shaft 3 is transmitted along the left crown of the clutch 31 by a pair of gears 22-23, shaft 5 to the front axle drive. The transmission operates in front-wheel drive mode with a 4x4 wheel formula.

 IV - we move the coupling 31 to the extreme right position (see figure 2, the lower position of the coupling): the left crown disengaged from the wide crown of the gear 22 and disengaged the front axle drive, this coupling crown closed the crown 24 of the secondary shaft 3 and the carrier 17 of the differential, as well as the crown of the 21 gears of the differential 20 - the differential is locked, the torque from the secondary shaft 3 is transmitted via a blocked differential to the shaft 4 of the rear axle drive. The transmission operates in rear-wheel drive mode with a 4x2 wheel formula. In another design, two narrow crowns on the tubular shaft of the gear 20, the left crown of the clutch 31 will close the crown 24 of the secondary shaft 3, and the right crown will close the second crown of the gear 20 located between the crown 21 and the housing wall.

 The positive effect is expressed in the reduction of the metal consumption of the unit by three gears and the expansion of its operational capabilities - four operating modes instead of two, as well as in an increase in transmission efficiency due to the direct transmission of torque from the differential to the rear axle (rear axle bridges).

Claims (1)

 A transfer case comprising a housing with primary, secondary and intermediate shafts located therein, the primary and secondary shafts being installed coaxially, and the intermediate shaft parallel to the coaxial shafts, gears on the secondary shaft mounted freely and constantly engaged with the gears of the intermediate shaft, between pairs of lower gears a three-position clutch is installed on the hub of the secondary shaft, a driven reverse gear is fixed on it, a separate reverse gear with a shift clutch is installed on axis, located between the secondary and intermediate shafts, the secondary shaft is connected to the differential, characterized in that the gear is mounted on the input shaft and engaged with the gear freely mounted on the intermediate shaft, which is also freely mounted another gear and a block of two lower gears and a reverse gear, between the first three rows of gears there are two twin shifting clutches, each of which consists of two single-acting coupling halves interconnected by a shifting fork one half-coupling is mounted on the ring gear of the intermediate shaft, the other half-coupling is opposite the first half-coupling either on the gear of the input shaft or on the gear of the secondary shaft, one half-coupling of the second twin coupling is mounted on the intermediate-shaft gear of the second or third row of gears, the other half-coupling is opposite the gear of the secondary shaft, the differential carrier with satellites is fixed at the output of the secondary shaft, one differential gear is fixed to the rear axle drive shaft, the other gear the gear shaft with a tubular shaft located on the secondary shaft is connected to the wide rim, next to it is a narrow rim mounted on the secondary shaft, a gear with a wide rim freely engaged on the shaft fixed to the intermediate shaft on the rims of the differential gears is freely mounted on this shaft Also, a four-position clutch is installed on the secondary shaft crown, which selectively connects the wide gear wheel of the intermediate shaft drive gear to the secondary shaft gear or the same crowns with a wide differential gear crown Ala or just wide crowns or gears secondary shaft crown with wide crown gear differential.

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