JP5410306B2 - Multistage transmission - Google Patents

Description

  The present invention relates to a multi-stage switching type transmission that can change the rotational speed of a main shaft of a main transmission into three stages of high speed, medium speed, and low speed by a sub-transmission.

  Conventionally, a range type transmission including a main transmission and a sub-transmission provided on a surface opposite to the clutch of the main transmission is known (see, for example, Patent Document 1). In this range type transmission, the main transmission is configured to be capable of shifting between the fifth forward speed and the first reverse speed, and the sub-transmission is configured to be capable of shifting to the high speed or low speed second speed. The main transmission includes first to fourth transmission gears and a back transmission gear that are rotatably fitted to the main shaft, a fifth transmission gear fixed to the rear end of the main shaft, and first to first transmission gears fixed to the counter shaft. 5 counter gear and back counter gear, a first sync mechanism provided between the first transmission gear and the back transmission gear, a second sync mechanism provided between the second transmission gear and the third transmission gear, And a third sync mechanism provided between the fourth transmission gear and the fifth transmission gear. The auxiliary transmission has a planetary gear mechanism and an auxiliary sync mechanism. The multi-stage changeable transmission can shift between the ninth forward speed and the first reverse speed by switching between the main transmission and the sub-transmission.

JP 2007-270946 A (paragraph [0009], paragraph [0013], paragraph [0014], FIG. 8)

  However, in the range type transmission shown in the above-mentioned conventional patent document 1, when the number of shift stages is increased by adding the transmission gear and the counter gear of the main transmission, the transmission gear and the counter gear of the main transmission are relatively large. Since it is necessary to add parts, there was a problem that a relatively large additional space had to be secured.

  It is an object of the present invention to increase the number of shift stages of the entire transmission by increasing a relatively small additional space, or to reduce the volume occupied by the entire transmission without changing the number of shift stages of the entire transmission. It is in providing a type transmission.

The first aspect of the present invention is that, as shown in FIG. 1, the output shaft 19 is changed by changing the rotational speed of the main transmission 11 and the main shaft 16 of the main transmission 11 in three stages of high speed, low speed and medium speed. The sub-transmission 13 includes a planetary gear mechanism 104 having a ring gear 106, and the counter-shaft for planetary gears is mounted on the counter shaft 20 of the main transmission 11. 113 is rotatably fitted , the ring gear 106 is provided with an external gear 106b that meshes with the planetary counter gear 113, and when the ring gear 106 is fixed to the case 18 of the auxiliary transmission 13, the output shaft 19 is in a low speed state, the output shaft 19 when the ring gear 106 is fixed to the output shaft 19 becomes the high speed state, the count for Yu star state where the ring gear 106 is not fixed to the case 18 and the output shaft 19 Characterized in that the output shaft 19 is configured such that the medium speed state when the gear 113 is fixed to the counter shaft 20.

The second aspect of the present invention is an invention based on the first aspect, and further, as shown in FIG. 5, an idle shaft 151 is provided at a position symmetrical to the counter shaft 20 with the main shaft 16 as the center. An idle gear 152 that meshes with the external gear 106b is attached to the idle shaft 151.

A third aspect of the present invention is an invention based on the first aspect, and further, as shown in FIG. 6, the counter counter shaft 171 is positioned symmetrically with respect to the counter shaft 20 centering on the main shaft 16. A planetary counter gear 173 that is provided and meshes with the external gear 106 b is attached to the counter counter shaft 171.

In a first aspect of the multi-stage switching type transmission of the present invention, the planetary counter gear rotatably fitted in the counter shaft of the main transmission, provided external gear meshing with the planetary counter gear to the ring gear, Yu By providing a mechanism for fixing the star counter gear to the counter shaft, the sub-transmission capable of switching two stages to high speed or low speed can be switched to medium speed. As a result, when the number of gears is increased by adding transmission gears and counter gears of the main transmission, relatively large parts such as transmission gears and counter gears must be added, and a relatively large additional space must be secured. Compared with a certain conventional range type transmission, in the present invention, it is necessary to attach a relatively large component called a planetary counter gear to the counter shaft of the main transmission, but the external teeth meshing with the planetary counter gear Since it is only necessary to provide the gears on the existing ring gear, the auxiliary transmission can be switched to three stages with a relatively small additional space, and the number of shift stages of the entire transmission can be increased. In the present invention, since the number of switching stages of the sub-transmission is increased from the conventional two to three, the number of speeds of the main transmission can be reduced when the number of speeds of the entire transmission is not changed. As a result, although a relatively large component called a planetary counter gear is added to the counter shaft of the main transmission, it is only necessary to provide an external gear that meshes with the planetary counter gear in the existing ring gear, and the main transmission. Since relatively large parts such as a transmission gear and a counter gear of the machine can be reduced, the volume occupied by the entire transmission can be reduced.

In the multi-stage switching transmission according to the second aspect of the present invention, an idle shaft is provided at a position symmetrical to the counter shaft centered on the main shaft, and an idle gear that meshes with an external gear is attached to the idle shaft. When the planetary counter gear drives the ring gear via the external gear, an offset load is applied to the ring gear, but the offset shaft receives the offset load via the idle gear. As a result, since an uneven load does not act on the ring gear, the durability of the planetary gear mechanism can be improved.

In the multi-stage switching transmission according to the third aspect of the present invention, a counterbalance shaft is provided at a position symmetrical to the countershaft centered on the main shaft, and the planetary gear meshes with the external gear on the counterbalance shaft. Since the counter counter gear is attached, when the planetary counter gear drives the ring gear via the external gear, an offset load is applied to the ring gear, but the planetary counter gear is also connected via the external gear. In order to drive the ring gear, an eccentric load tends to act on the ring gear. However, since the planetary counter gear is provided at a symmetrical position with respect to the planetary counter gear with the main shaft as the center, the two unbalanced loads that act on the ring gear cancel each other, and the ring gear Uneven load does not work. As a result, the durability of the planetary gear mechanism can be improved.

It is a longitudinal section lineblock diagram showing the multistage change-type transmission of a 1st embodiment of the present invention. FIG. 5 is a cross-sectional view taken along line AA of FIG. 4 illustrating a process of shifting the multi-stage switching transmission from the fourth speed stage or the fifth speed stage to the sixth speed stage or the seventh speed stage. FIG. 5 is a cross-sectional view taken along line AA of FIG. 4 showing a process of shifting the multi-stage switching transmission from the eighth speed or the ninth speed to the tenth speed or the eleventh speed. It is the BB sectional view taken on the line of Fig.2 (a). It is a longitudinal cross-sectional block diagram which shows the multistage switching transmission of 2nd Embodiment of this invention. It is a longitudinal cross-sectional block diagram which shows the multistage switching transmission of 3rd Embodiment of this invention.

Next, an embodiment for carrying out the present invention will be described with reference to the drawings.
<First Embodiment>
As shown in FIG. 1, a multi-stage switching transmission 10 mounted on a truck includes a main transmission 11 and a sub-transmission 13 provided on the surface of the main transmission 11 opposite to the clutch 12. Prepare. In this embodiment, the main transmission 11 is configured to be capable of shifting to five forward speeds and the first reverse speed, and the sub-transmission 13 is configured to be capable of shifting to three speeds of high speed, medium speed, or low speed. . The multi-stage changeable transmission 10 can shift between 13 forward speeds and 1 reverse speed. An input shaft 14 is rotatably inserted into the clutch case 12 a via a first bearing 21, and a main shaft 16 is inserted into the clutch case 12 containing the main transmission 11 via second and third bearings 22 and 23. An output shaft 19 is rotatably inserted through the fourth and fifth bearings 24 and 25 into the auxiliary transmission case 18 that is rotatably inserted and accommodates the auxiliary transmission 13. The front end of the input shaft 14 is connected to a crankshaft (not shown) via the clutch 12. The front end of the main shaft 16 is loosely inserted into the rear end of the input shaft 14 and held by the second bearing 22, and the front end of the output shaft 19 is loosely fitted to the rear end of the main shaft 16 and held by the fourth bearing 24. Accordingly, the main shaft 16 is configured to be rotatable relative to the input shaft 14, and the output shaft 19 is configured to be rotatable relative to the main shaft 16. A counter shaft 20 is inserted into the main transmission case 17 and the sub transmission case 18 in parallel with the main shaft 16, and the counter shaft 20 is rotatably held by sixth to eighth bearings 26 to 28.

  On the other hand, above the transmission gears 41 to 46 of the main transmission 11, first to third gear shift shafts 51 to 53 are circumferentially spaced around the transmission gears 41 to 46 and parallel to the main shaft 16. (FIGS. 1 to 4). These gear shift shafts 51 to 53 are arranged in the order of the first gear shift shaft 51, the third gear shift shaft 53, and the second gear shift shaft 52 from the right side, and the first to third gear shift shafts 51 to 53 have the first to third gear shift shafts. Shift forks 61 to 63 (FIG. 1) are respectively fitted. The interval between the first gear shift shaft 51 and the third gear shift shaft 53 adjacent to each other is formed relatively wide, and the interval between the third gear shift shaft 53 and the second gear shift shaft 52 adjacent to each other is formed relatively small (see FIG. 2 to 4), that is, the second gear shift shaft 52 is provided outside the third gear shift shaft 53 and close to the third gear shift shaft 53. Above the first to third gear shift shafts 51 to 53, there is provided a select shift shaft 64 that three-dimensionally intersects with the gear shift shafts 51 to 53 at right angles, and the select shift shaft 64 has a select shift lever 66. Is attached (FIGS. 2 and 3). The select shift lever 66 is fitted to the select shift shaft 64, and is configured to move in this axial direction together with the select shift shaft 64 and to rotate about this axis. The select shift lever 66 has a fitting portion 66a fitted at a predetermined position of the select shift shaft 64, and a single protrusion 66b suspended from the fitting portion 66a. The tip of the projection 66b is configured to enter between the first and third gear shift shafts 51 and 53. It should be noted that the select shift shaft may intersect three-dimensionally at an angle other than a right angle as long as it intersects the gear shift axis.

  On the other hand, the first to third gear shift shafts 51 to 53 are respectively attached with the first to fourteenth engagement pieces 71 to 84, and these engagement pieces 71 to 84 are all the first and third gear shift shafts 51 and 53. (FIGS. 2 to 4). In other words, the first to fourteenth engaging pieces 71 to 84 are arranged in two rows with a first predetermined interval in the axial direction of the gear shift shafts 51 to 53, and in the axial direction of the select shift shaft 64. A second predetermined interval that is narrower than the interval is provided and arranged side by side in the axial direction of the select shift shaft 64. The first and fourteenth engaging pieces 71, 84 are attached to the first gear shift shaft 51, and the second, third, sixth, seventh, tenth and eleventh engaging pieces 72, 73, 76, 77, 80 are provided. , 81 are attached to the second gear shift shaft 52, and the fourth, fifth, eighth, ninth, twelfth and thirteenth engagement pieces 74, 75, 78, 79, 82, 83 are attached to the third gear shift shaft 53. Mounted. Specifically, the first and fourteenth engagement pieces 71, 84 are provided on the first boss portion 51 a fitted to the first gear shift shaft 51, and have a predetermined interval in the axial direction of the first gear shift shaft 51. It is configured to open and project toward the third gear shift shaft 53. The second and third engagement pieces 72 and 73 are provided on the second boss portion 52 a fitted to the second gear shift shaft 52 via a pair of linear arm portions 52 b and 52 b, and the second gear shift shaft 52. The first and second engaging pieces 84 and 71 are adjacent to each other with a predetermined interval in the axial direction. The pair of linear arm portions 52b, 52b is configured to pass between the third gear shift shaft 53 and the main shaft 16, that is, between the third gear shift shaft 53 and the outer peripheral surfaces of the transmission gears 41 to 46, and The third engaging pieces 72 and 73 project upward from the tip ends of the pair of linear arm portions 52b and 52b, respectively.

  The fourth and fifth engagement pieces 74 and 75 are provided on the third boss portion 53 a fitted to the third gear shift shaft 53 via a pair of bent arm portions 53 b and 53 b, and the axial direction of the third gear shift shaft 53 The first and second engagement pieces 72 and 73 are adjacent to each other with a predetermined interval therebetween. The pair of bent arm portions 53b, 53b are formed to be bent from both ends of the third boss portion 53a so as to face between the first and third boss portions 51a, 53a, respectively, and the fourth and fifth engaging pieces 74, 75 are formed. Are projected upward from the tip ends of the pair of bent arm portions 53b, 53b. The sixth and seventh engaging pieces 76 and 77 are provided so as to project upward from the ends in the longitudinal center of the pair of linear arm portions 52b and 52b, respectively, and the fourth and fifth engaging pieces 74 and 75 are provided. Are adjacent to each other. The eighth and ninth engagement pieces 78 and 79 are respectively upward from the distal end portions of the pair of intermediate arm portions 53c and 53c (FIG. 4) extending in a direction approaching each other from the longitudinal center of the pair of bent arm portions 53b and 53b. The third gear shift shaft 53 is protruded, and is configured to be adjacent to the sixth and seventh engagement pieces 76 and 77 with a predetermined interval in the axial direction. The tenth and eleventh engagement pieces 80, 81 project upward from the proximal end of the longitudinal center of the pair of linear arm portions 52b, 52b, respectively, and the eighth and ninth engagement pieces 78, 79 are provided. Are adjacent to each other. Further, the twelfth and thirteenth engagement pieces 82 and 83 are provided on the third boss portion 53a so as to protrude toward the first gear shift shaft 51 at a predetermined interval in the axial direction of the third gear shift shaft 53. Composed.

  In other words, the first and thirteenth engaging pieces 71 and 83 project laterally from the first and third gear shift shafts 51 and 53 so as to face each other, and between the first and thirteenth engaging pieces 71 and 83. In addition, third, fifth, seventh, ninth and eleventh engagement pieces 73, 75, 79, 81 are provided in this order from the right side in the axial direction of the select shift shaft 64 (FIG. 4). The fourteenth and twelfth engagement pieces 84 and 82 project laterally from the first and third gear shift shafts 51 and 53 so as to face each other, and between the fourteenth and twelfth engagement pieces 84 and 82. In addition, second, fourth, sixth, eighth and tenth engagement pieces 72, 74, 76, 78, 80 are provided in this order from the right side in the axial direction of the select shift shaft 64. Further, the interval between the 14th and first engagement pieces 84, 71, the interval between the second and third engagement pieces 72, 73, the interval between the fourth and fifth engagement pieces 74, 75, the sixth and seventh engagements. The distance between the pieces 76 and 77, the distance between the eighth and ninth engaging pieces 78 and 79, the distance between the tenth and eleventh engaging pieces 80 and 81, and the distance between the twelfth and thirteenth engaging pieces 82 and 83 are: This is an interval at which the tip of the protrusion 66b of the select shift lever 66 can be loosely inserted, and the select shift lever 66 moves in the axial direction of the select shift shaft 64 so that the tip of the protrusion 66b is the first to fourteenth engaging pieces 71. ˜84 are configured to selectively engage.

  Returning to FIG. 1, the main transmission 11 includes first to fourth transmission gears 41 to 44 and a back transmission gear 46 that are rotatably fitted to the main shaft 16, and a fifth gear fixed to the rear end of the main shaft 16. A first synchronization mechanism provided between the transmission gear 45, the first to fifth counter gears 91 to 95 and the back counter gear 96 fixed to the counter shaft 20, and the first transmission gear 41 and the back transmission gear 46. 101, a second synchronization mechanism 102 provided between the second transmission gear 42 and the third transmission gear 43, and a third synchronization mechanism 103 provided between the fourth transmission gear 44 and the fifth transmission gear 45. . The first to fourth transmission gears 41 to 44 are rotatably fitted to the main shaft 16 via the ninth to twelfth bearings 29 to 32 and the back transmission gear 46 is rotatably fitted to the main shaft 16 via the thirteenth bearing 33. The first to fifth transmission gears 41 to 45 mesh with the first to fifth counter gears 91 to 95, respectively, and the back transmission gear 46 and the back counter gear 96 are fixed to an intermediate shaft (not shown). It is configured to mesh through an intermediate gear (not shown). Since the first to third synchronization mechanisms 101 to 103 are configured substantially the same, the first synchronization mechanism 101 will be described as a representative, and the description of the second and third synchronization mechanisms 102 and 103 will be omitted. The first sync mechanism 101 includes a clutch hub 101a fitted to the rear portion of the main shaft 16 and having an outer spline formed on the outer peripheral surface thereof, and an outer surface identical to the outer spline of the hub 101a fixed to the first transmission gear 41 on the outer peripheral surface. The first clutch gear 101b formed with a spline, the back clutch gear 101c fixed to the back transmission gear 46 and formed with the same outer spline as the outer spline of the hub 101a, and the outer spline of the hub 101a. An inner spline is formed, and a sleeve 101d is movably fitted to the hub 101a so as to be movable in the axial direction of the main shaft 16 but not relatively rotatable with respect to the hub 101a, and the sleeve 101d is moved in the axial direction of the main shaft 16. The inner spline of the sleeve 101d is connected to the first clutch gear 101b or the back clutch gear. And a first shift fork 61 which can mesh with the outer splines of 101c. The sleeve 101d and the first clutch gear 101b or the back clutch gear 101c are smoothly engaged between the clutch hub 101a and the first clutch gear 101b or between the clutch hub 101a and the back clutch gear 101c. For this purpose, a known synchronizer ring (not shown) is provided.

  On the other hand, the auxiliary transmission 13 includes a planetary gear mechanism 104, a first auxiliary synchronization mechanism 111, and a second auxiliary synchronization mechanism 112 (FIG. 1). The planetary gear mechanism 104 includes a sun gear 105 fitted to the rear end portion of the main shaft 16, a large-diameter substantially bowl-shaped ring gear 106 that is rotatably fitted to the output shaft 19 via a fourteenth bearing 34, A large-diameter internal gear 106a integrally provided on the inner surface of the large-diameter portion of the ring gear 106, a large-diameter external gear 106b integrally provided on the outer surface of the large-diameter portion of the ring gear 106, and an output shaft A plurality of substantially circular disc-shaped holding portions 107 provided at the front end portion of 19 and a plurality of pins 108 that are rotatably fitted to the holding portions 107 at a predetermined interval in the circumferential direction. Planetary gear 109. The first sub-synchronization mechanism 111 is configured in substantially the same manner as the first to third synchronization mechanisms 101 to 103, and is a clutch hub 111a that is fitted to the small diameter portion of the ring gear 106 and has an outer spline formed on the outer peripheral surface thereof. A high speed clutch gear 111b fixed to the output shaft 19 and having the same outer spline as the outer spline of the hub 111a on the outer peripheral surface, and an outer spline fixed to the auxiliary transmission case 18 and the same as the outer spline of the hub 111a. The formed low speed clutch gear 111c and an inner spline that meshes with the outer spline of the hub 111a are formed. The hub 111a is movable in the axial direction of the output shaft 19 and is not rotatable relative to the hub 111a. The fitted sleeve 111d, and the sleeve 111d is moved in the axial direction of the output shaft 19 to move the sleeve And a interlockable first sub shift fork 111e 11d the inner splines of the outer splines of the high-speed clutch gear 111b or low speed clutch gear 111c.

  A planetary counter gear 113 that meshes with the external gear 106 b of the ring gear 106 is rotatably fitted via a fifteenth bearing 35 in a portion of the counter shaft 20 that is accommodated in the auxiliary transmission case 18. The second sub-synchronization mechanism 112 includes a clutch hub 112a that is fitted to the counter shaft 20 and has an outer spline formed on the outer peripheral surface thereof, and an outer surface that is fixed to the planetary counter gear 113 and that has the same outer spline as the hub 112a. A medium speed clutch gear 112b formed with a spline and an inner spline meshing with the outer spline of the hub 112a are formed so that the hub 112a can move in the axial direction of the counter shaft 20 and rotate relative to the hub 112a. A sleeve 112c that is loosely fitted, and a second sub-shift fork 112d that can move the sleeve 112c in the axial direction of the counter shaft 20 and mesh the inner spline of the sleeve 112c with the outer spline of the medium speed clutch gear 112b. And have.

  Reference numeral 114 in FIGS. 2 and 3 is a change-over switch that can be switched to three positions in order to change the rotational speed of the main shaft 16 in three stages of high speed, medium speed, and low speed and transmit it to the output shaft 19. The changeover switch 114 has a switch main body 114a and a plunger 114b provided so as to be movable in and out of the switch main body 114a. The changeover switch 114 changes to the first to third states depending on the pushing amount of the plunger 114b into the switch main body 114a. And it is comprised so that the signal according to the state may be sent to a controller (not shown). The plunger 114b protrudes toward the upper surface of the fitting portion 66a of the select shift lever 66, and the upper surface of the fitting portion 66a of the select shift lever 66 is gradually increased from the right to the first to third protruding portions 66c, 66d and 66e are provided. In the plunger 114b, the protrusion 66b of the select shift lever 66 is positioned at the first engaging portion 121 (FIG. 4) between the first engaging piece 71 and the fourteenth engaging piece 84, or the second engaging piece. The second engagement portion 122 (FIG. 4) between the second engagement portion 72 and the third engagement piece 73 or the third engagement portion between the fourth engagement piece 74 and the fifth engagement piece 75 When it is positioned at 123 (FIG. 4), it contacts the first protrusion 66c and protrudes most from the switch body 114a to be in the first state (FIG. 2 (a)). Further, the projection 66b of the select shift lever 66 is positioned at the fourth engagement portion 124 (FIG. 4) between the sixth engagement piece 76 and the seventh engagement piece 77, or the eighth engagement piece 78 and the eighth engagement piece 78. When positioned at the fifth engaging portion 125 (FIG. 4) between the nine engaging pieces 79, the second projecting portion 66d comes into contact with and is pushed into the switch body 114a by a predetermined amount to enter the second state. (FIG. 2B and FIG. 3A). Further, the projection 66b of the select shift lever 66 is positioned at the sixth engaging portion 126 (FIG. 4) between the tenth engaging piece 80 and the eleventh engaging piece 81, or the twelfth engaging piece 82 and the When it is located at the seventh engaging portion 127 (FIG. 4) between the 13 engaging pieces 83, it comes into contact with the third protrusion 66e and is pushed most into the switch main body 114a to enter the third state (FIG. 3 (b)).

When the changeover switch 114 is in the first state, the controller does not engage the inner spline of the sleeve 112c of the second sub-sync mechanism 112 with the outer spline of the medium-speed clutch gear 112b, and the sleeve of the first sub-sync mechanism 111. The clutch hub 111a and the low speed clutch gear 111c are connected by 111d. Since thereby the ring gear 106 and the internal gear 106a is fixed to the sub transmission casing 18, configured so that the rotational speed N ₁ of the main shaft 16 is transmitted to the output shaft 19 is decelerated by the large reduction ratio. That is, the rotational speed N ₂ of the output shaft 19 is [N ₁ Z ₁ / (Z ₁ + Z ₂ )] (Z ₁ : number of teeth of the sun gear 105, Z ₂ : number of teeth of the internal gear 106 a, N ₁ : main shaft 16 rotation speed). When the changeover switch 114 is in the second state, the controller does not engage the inner spline of the sleeve 111d of the first sub-sync mechanism 111 with either the outer spline of the high speed clutch gear 111b or the low speed clutch gear 111c. The clutch hub 112a and the medium speed clutch gear 112b are connected by the sleeve 112c of the second sub-sync mechanism 112. As a result, the external gear 106b meshes with the clutch hub 112a via the planetary counter gear 113 , the medium speed clutch gear 112b and the sleeve 112c in a state where the ring gear 106 is not fixed to the auxiliary transmission case 18 and the output shaft 19. The planetary counter gear 113 is fixed to the counter shaft 20, and the rotational speed N ₁ of the main shaft 16 is decelerated at a relatively small reduction ratio and transmitted to the output shaft 19. That is, the rotational speed N ₂ of the output shaft 19 is [{N ₁ Z ₁ / (Z ₁ + Z ₂ )} + {N ₀ Z ₄ Z ₅ / (Z ₃ Z ₆ )}] (Z ₁ : sun gear 105 Number of teeth, Z ₂ : Number of teeth of internal gear 106 a, Z ₃ : Number of teeth of external gear 106 b, Z ₄ : Number of teeth of planetary counter gear 113, Z ₅ : Number of teeth of fifth transmission gear 45, Z ₆ : number of teeth of the fifth counter gear 95, N ₀ : rotational speed of the input shaft 14, and N ₁ : rotational speed of the main shaft 16. Further, when the changeover switch 114 is in the third state, the controller does not mesh the inner spline of the sleeve 112c of the second sub-sync mechanism 112 with the outer spline of the medium-speed clutch gear 112b, and the sleeve of the first sub-sync mechanism 111. The clutch hub 111a and the high speed clutch gear 111b are connected by 111d. As a result, the ring gear 106 and the output shaft 19 are fixed to each other and rotate at the same rotational speed, so that the rotational speed N ₁ of the main shaft 16 is transmitted to the output shaft 19 while keeping the same. That is, the rotational speed N ₂ of the output shaft 19 is the same as the rotational speed N ₁ of the main shaft 16. From the above, when the gear position of the main transmission 11 is fixed, when the changeover switch 114 is switched to the first state, the output shaft 19 rotates at a low speed and the changeover switch 114 is switched to the second state. When the output shaft 19 rotates at a medium speed and the changeover switch 114 is switched to the third state, the output shaft 19 rotates at a high speed. An operation lever (not shown) operated by the driver is provided in the driver seat of the truck, and this operation lever can be switched to either the 13th forward speed position or the first reverse speed position. .

In the multi-stage switching transmission 10 configured as described above, the planetary counter gear 113 is rotatably fitted on the counter shaft 20 of the main transmission 11, and the external gear 106b meshing with the planetary counter gear 113 is connected to the ring gear. provided 106, by providing the second synchro mechanism 112 for fixing the Yu star counter gear 113 to the counter shaft 20, and can be switched to medium speed 2 stage switchable auxiliary transmission 13 to high or low speed . As a result, the number of shift stages of the entire transmission 10 can be increased with an increase in additional space that is smaller than when the transmission gear and the counter gear of the main transmission 11 are increased. That is, if a relatively large component such as a transmission gear and a counter gear of the main transmission 11 is added to increase the number of shift stages of the transmission 10 as a whole, a relatively large additional space must be secured. On the other hand, in the present embodiment, it is necessary to attach a relatively large component called the planetary counter gear 113 to the counter shaft 20, but the external gear 106b that meshes with the planetary counter gear 113 is replaced with the existing ring gear 106. Therefore, it is possible to increase the number of shift stages of the entire transmission 10 with a relatively small additional space.

  The operation of the thus configured multi-stage switching transmission 10 will be described. First, the driver starts the engine with the operation lever maintained at the neutral position. Next, when the driver operates the operation lever to the first gear position, the projection 66b of the select shift lever 66 is moved to the first engagement portion 121 (FIG. 4) between the first and fourteenth engagement pieces 71 and 84. After being positioned, the first gear shift shaft 51 is moved in the axial direction (FIGS. 2 and 4). At this time, the plunger 114b of the changeover switch 114 abuts on the first protrusion 66c of the select shift lever 66, and the changeover switch 114 is in the first state (FIG. 2A). Thus, the controller is in a state where the inner spline of the sleeve 112c of the second sub-sync mechanism 112 of the sub-transmission 13 is not meshed with the outer spline of the medium-speed clutch gear 112b, and the clutch hub 111a of the first sub-sync mechanism 111. And the low-speed clutch gear 111c are connected, the first shift fork 61 connects the clutch hub 101a of the first synchro mechanism 101 and the first transmission gear 41 (FIG. 1). As a result, the rotational force of the input shaft 14 is decelerated by the fifth transmission gear 45 and the fifth counter gear 95 and then decelerated at a large reduction ratio by the first counter gear 91 and the first transmission gear 41 and transmitted to the main shaft 16. At the same time, the planetary gear mechanism 104 of the auxiliary transmission 13 is decelerated at a large reduction ratio and transmitted to the output shaft 19. When the driver operates the operation lever to any of the second to fifth gear positions, the controller moves the inner spline of the sleeve 112c of the second sub-sync mechanism 112 of the sub-transmission 13 to the medium-speed clutch gear 112b. The second or third shift forks 62, 63 are in the second or second state when the clutch hub 111a and the low speed clutch gear 111c of the first sub-sync mechanism 111 are connected. The clutch hubs 102a, 103a of the three sync mechanisms 102, 103 are connected to either the second or third transmission gears 42, 43 or the fourth or fifth transmission gears 44, 45. As a result, when the operation lever is sequentially operated up to the second to fifth gear positions, the rotation speed of the output shaft 19 increases stepwise.

  When the driver operates the operation lever to the sixth speed position, the projection 66b of the select shift lever 66 is positioned at the fourth engagement portion 124 (FIG. 4) between the sixth and seventh engagement pieces 76, 77. Later, the second gear shift shaft 52 is moved in the axial direction (FIGS. 2 and 4). At this time, the plunger 114b of the changeover switch 114 comes into contact with the second protrusion 66d of the select shift lever 66, and the changeover switch 114 is in the second state (FIG. 2B). Thus, the controller is in a state where the clutch hub 111a of the first sub-sync mechanism 111 of the sub-transmission 13 is not connected to either the low-speed clutch gear 111c or the high-speed clutch gear 111b, and the second sub-sync mechanism 112 With the inner spline of the sleeve 112c engaged with the outer spline of the medium speed clutch gear 112b, the second shift fork 62 connects the clutch hub 102a of the second sync mechanism 102 and the second transmission gear 42 (FIG. 1). ). As a result, the rotational force of the input shaft 14 is decelerated by the fifth transmission gear 45 and the fifth counter gear 95, and then decelerated by the second counter gear 92 and the second transmission gear 42 with a relatively small reduction ratio, so that the main shaft 16 , And the planetary gear mechanism 104 of the auxiliary transmission 13 is decelerated at a relatively small reduction ratio and transmitted to the output shaft 19. At this time, the rotational speed of the output shaft 19 is higher by one step than the rotational speed of the output shaft 19 when the operation lever is operated to the fifth speed position. When the driver operates the operation lever to any of the seventh to ninth gear positions, the controller moves the clutch hub 111a of the first sub-sync mechanism 111 of the sub-transmission 13 to the low-speed clutch gear 111c and the high-speed gear. The second or third shift fork is in a state where it is not connected to any of the clutch gears 111b and the inner spline of the sleeve 112c of the second sub-sync mechanism 112 is engaged with the outer spline of the medium speed clutch gear 112b. 62 and 63 connect the clutch hubs 102a and 103a of the second or third synchronization mechanism 102 and 103 to either the third transmission gear 43 or the fourth or fifth transmission gears 44 and 45, respectively. As a result, when the operation lever is sequentially operated from the seventh to ninth gear positions, the rotation speed of the output shaft 19 increases stepwise.

  When the driver operates the operation lever to the tenth speed position, the projection 66b of the select shift lever 66 is positioned at the sixth engagement portion 126 (FIG. 4) between the tenth and eleventh engagement pieces 80 and 81. Later, the second gear shift shaft 52 is moved in the axial direction (FIGS. 3 and 4). At this time, the plunger 114b of the changeover switch 114 comes into contact with the third protrusion 66e of the select shift lever 66, and the changeover switch 114 is in the third state (FIG. 3B). Thus, the controller is in a state where the inner spline of the sleeve 112c of the second sub-sync mechanism 112 of the sub-transmission 13 is not meshed with the outer spline of the medium-speed clutch gear 112b, and the clutch hub 111a of the first sub-sync mechanism 111. And the high speed clutch gear 111b are connected, the second shift fork 62 connects the clutch hub 102a of the second synchro mechanism 102 and the second transmission gear 42 (FIG. 1). As a result, the rotational force of the input shaft 14 is decelerated by the fifth transmission gear 45 and the fifth counter gear 95, and then decelerated by the second counter gear 92 and the second transmission gear 42 with a relatively small reduction ratio, so that the main shaft 16 Is transmitted to the output shaft 19 without being decelerated or increased by the planetary gear mechanism 104 of the auxiliary transmission 13. At this time, the rotational speed of the output shaft 19 is higher by one step than the rotational speed of the output shaft 19 when the operating lever is operated to the ninth gear position. When the driver operates the operation lever to any one of the first to thirteenth speed positions, the controller moves the inner spline of the sleeve 112c of the second sub-sync mechanism 112 of the sub-transmission 13 to the medium-speed clutch gear 112b. The second or third shift forks 62, 63 are in the second or second state when the clutch hub 111a and the high-speed clutch gear 111b of the first sub-sync mechanism 111 are connected to each other. The clutch hubs 102a, 103a of the three synchro mechanisms 102, 103 are connected to either the third transmission gear 43 or the fourth or fifth transmission gears 44, 45. As a result, when the operation lever is operated in order from the 11th to 13th speed positions, the rotation speed of the output shaft 19 increases stepwise.

<Second Embodiment>
FIG. 5 shows a second embodiment of the present invention. 5, the same reference numerals as those in FIG. 1 denote the same components. In this embodiment, an idle shaft 151 is provided at a symmetrical position with respect to the counter shaft 20 centering on the main shaft 16, and an idle gear 152 that meshes with the external gear 106 b of the ring gear 106 is attached to the idle shaft 151. Both ends of the idle shaft 151 are rotatably attached to the main transmission case 17 and the auxiliary transmission case 18 via bearings 153 and 154, respectively, and the idle gear 152 is rotatably fitted to the idle shaft 151 via the bearing 155. The idle gear 152 is formed in the same shape as the planetary counter gear 113. The configuration other than the above is the same as that of the first embodiment.

  In the multi-stage switching transmission 150 configured as described above, when the planetary counter gear 113 drives the ring gear 106 via the external gear 106b, an eccentric load tends to act on the ring gear 106. Is received by the idle shaft 151 via the idle gear 152. As a result, no eccentric load acts on the ring gear 106, so that the durability of the planetary gear mechanism 104 can be improved. Since the operation other than the above is substantially the same as the operation of the first embodiment, repeated description will be omitted.

<Third Embodiment>
FIG. 6 shows a third embodiment of the present invention. 6, the same reference numerals as those in FIG. 1 denote the same components. In this embodiment, a counterbalance shaft 171 is provided at a symmetrical position with respect to the countershaft 20 with the main shaft 16 as the center, and the counterbalance fishing shaft 171 meshes with the external gear 106b of the ring gear 106 for planetary fishing. A combined counter gear 173 is attached. The counter counter shaft 171 is rotatably attached to the main transmission case 17 and the sub transmission case 18 via bearings 174, 175 and 176, and the planetary counter gear 173 is connected to the counter counter shaft 171 via a bearing 177. And is rotatably inserted. The planetary counter gear 173 is formed in the same shape as the planetary counter gear 113. Further, the counter counter shaft 171 includes first to fifth counter gears 181 to 185 and a counter counter gear 186 for back that mesh with the first to fifth gears 41 to 45 and the back gear 46, respectively. It is inserted. The first to fifth counter gears 181 to 185 and the back counter gear 186 are formed in the same shape as the first to fifth counter gears 91 to 95 and the back counter gear 96, respectively. The configuration other than the above is the same as that of the first embodiment.

  In the multi-stage switching transmission 170 configured as described above, when the planetary counter gear 113 drives the ring gear 106 via the external gear 106b, an offset load is applied to the ring gear 106. Since the counter counter gear 173 also drives the ring gear 106 via the external gear 106 b, an unbalanced load tends to act on the ring gear 106. However, the counter counter shaft 171 is provided at a position symmetric with respect to the counter shaft 20 with the main shaft 16 as the center, and the planetary balance is at a position symmetrical with respect to the planetary counter gear 113 with the main shaft 16 as the center. Since the counter gear 173 is provided, the two unbalanced loads to be applied to the ring gear 106 cancel each other, and the unbalanced load does not act on the ring gear 106. As a result, the durability of the planetary gear mechanism 104 can be improved. Since the operation other than the above is substantially the same as the operation of the first embodiment, repeated description will be omitted.

  In the first and second embodiments, the truck is described as the vehicle on which the multistage switching transmission of the present invention is mounted. However, a bus or other vehicles may be used. In the first and second embodiments, the auxiliary transmission is provided on the surface opposite to the clutch of the main transmission. However, the auxiliary transmission may be provided between the clutch and the main transmission. Good. Further, in the first and second embodiments, three gear shift shafts of the main transmission are provided so that the entire transmission can be shifted to the 13th forward speed and the first reverse speed. Three gear shift shafts are provided and the entire transmission is configured with 12 forward speeds and 2 reverse speeds, or two gear shift shafts of the main transmission are provided and the entire transmission is 11 forward speeds and 1 reverse speed. Alternatively, it is configured with 9 forward speeds and 1 reverse speed, 4 gear shift shafts of the main transmission are provided, and the entire transmission is configured with 18 forward speeds and 2 reverse speeds, or the gear shift of the main transmission. Five or more shafts may be provided to further increase the number of shift stages of the entire transmission. Here, the gear shift shaft of the main transmission is reduced from three to two, and the entire transmission is configured with 11 forward speeds and 1 reverse speed, or 9 forward speeds and 1 reverse speed. In the present invention, when the number of gears is slightly increased or not changed, the main transmission is compared with a conventional multi-stage switching transmission (range transmission) having a two-stage switching sub-transmission. Although a comparatively large component called a planetary counter gear is added to the counter shaft of this planetary gear, it is only necessary to provide an external gear that meshes with the planetary counter gear on the existing ring gear, and two sets of gear shifts of the main transmission. Since relatively large parts such as a gear and a counter gear can be reduced, there is an advantage that the volume occupied by the entire transmission can be reduced.

10, 150, 170 Multi-stage switchable transmission 11 Main transmission 13 Sub transmission 16 Main shaft 18 Sub transmission case 19 Output shaft 20 Counter shaft 104 Planetary gear mechanism 106 Ring gear 106b External gear 113 Planetary counter gear 151 Idle shaft 152 Idle Gear 171 Counter counter shaft 173 Planetary counter counter gear

Claims (3)

A sub-transmission (13) capable of shifting the rotational speed of the main transmission (11) and the main shaft (16) of the main transmission (11) in three stages of high speed, low speed or medium speed and transmitting it to the output shaft (19). )
The auxiliary transmission (13) is constituted by a planetary gear mechanism (104) having a ring gear (106),
A planetary counter gear (113) is rotatably fitted on the counter shaft (20) of the main transmission (11),
The ring gear (106) is provided with an external gear (106b) that meshes with the planetary counter gear (113),
When the ring gear (106) is fixed to the case (18) of the auxiliary transmission (13), the output shaft (19) is in a low speed state,
When the ring gear (106) is fixed to the output shaft (19), the output shaft (19) is in a high speed state,
Said output shaft when said ring gear (106) is the case (18) and before Symbol planetary counter gear in a state not fixed to the output shaft (19) (113) is fixed to the counter shaft (20) (19) A multi-stage changeable transmission characterized by being configured to be in a medium speed state. An idle gear (151) is provided at a position symmetrical to the counter shaft (20) about the main shaft (16), and the idle gear meshes with the external gear (106b) on the idle shaft (151). The multi-stage transmission according to claim 1, wherein (152) is attached. A counter counter shaft (171) is provided at a position symmetric with respect to the counter shaft (20) with the main shaft (16) as the center, and the counter gear (106) is connected to the counter counter shaft (171). The multi-stage switching transmission according to claim 1, further comprising a planetary counter gear (173) that meshes with the planetary counter gear.

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