JP2012013099A - Range type multistage transmission - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent wear in a synchronizing mechanism without increasing the number of components, to prevent a sub-transmission from stopping at a neutral position and to prevent a so-called overrun phenomenon.SOLUTION: A range transmission includes: a main transmission; a sub-transmission that changes a rotation speed of an input to the main transmission or of an output from the main transmission into at least two stages of higher or lower speeds; a plurality of gear shift shafts 51 to 53 disposed in the periphery of a transmission gear of the main transmission, along a circumferential direction at a given interval and parallel to the main shaft of the main transmission, with a main shift fork attached to each shaft; and a select shift lever 67 mounted on a select shift shaft 66 three-dimensionally intersecting the gear shift shafts, and moving in the axial direction of the select shift shaft and rotating in the rotation direction of the select shift shaft. In the strokes of the select shift lever in the axial direction of the select shift shaft, a stroke upon shifting in the main transmission and the bus-transmission is longer than a stroke upon shifting only in the main transmission.

Description

  The present invention relates to a range-type multi-stage transmission capable of shifting the rotational speed of a main shaft of a main transmission to at least two stages of high speed and low speed by a sub transmission.

  Conventionally, the shift-and-select shaft moves in the axial direction by the shift-and-select operation or rotates around the shaft, and the forward-stage inner lever and the reverse-stage inner lever operate integrally with the shift-and-select shaft, When the interlock member is engaged with a shift fork head other than the shift fork head selected by the shift and select shaft, the shift fork head in the non-selected state is prevented from being shifted, and further, during the shift operation to the reverse gear, A reverse gear squeezing prevention transmission is disclosed in which the engagement mechanism is configured to temporarily apply an operation force for causing a shift operation for a synchronous movement to one forward shift fork head by the forward shift inner lever. (For example, refer to Patent Document 1). In this reverse gear squealing prevention transmission, the interlock member movement restricting means restricts the movement of the interlock member other than the movement of the shift fork head in the arrangement direction. By being arranged in one forward shift fork head in the selected state, a shift operation corresponding to the synchronization of one forward shift fork head is made possible. Further, the sub head interlocked with the shift operation of one forward shift fork head contacts the interlock member in the reverse shift state, thereby preventing the shift operation corresponding to the synchronization of one forward shift fork head. At the same time, when the operating force at the time of reverse gear selection is applied to the shift and select shaft, the shift member is brought into a non-contact state with the interlock member, and the shift operation corresponding to the synchronization of one shift gear fork head is permitted. Configured as follows.

  In the reverse gear squeezing prevention transmission configured as described above, the interlock member is restricted from moving in the direction in which the shift fork heads are arranged by the interlock member movement restricting means. Even in such a case, the interlock member itself cannot move so that the synchronizer functions. However, a marginal space is formed in the interlock member, and this marginal space is arranged on one forward shift fork head in the reverse stage selected state, so that one forward stage shift in the reverse stage selected state The fork head can be shifted in synchronization. As a result, even if the interlock member itself does not move so as to function the synchronizer, it is possible to cause a shift operation for a marginal space by a temporary engagement mechanism for one forward shift fork head. It has become. As a result, the shift operation for the synchronization can be executed for one forward shift fork head by the temporary engagement mechanism during the reverse shift, and the transmission input shaft and the output shaft can be synchronized. Gear noise can be prevented.

  However, since a sub head that is linked to the shift operation of one forward shift fork head is provided, this sub head is brought into contact with the interlock member when the interlock member is in the reverse shift state. One forward shift fork head is prevented from shifting in synchronization. However, when the operating force at the time of reverse gear selection is applied to the shift and select shaft, the sub head is not in contact with the interlock member, so that the sub head is 1 when shifting to the reverse gear. It does not prevent the two forward shift fork heads from performing the shifting operation for the synchronization. Therefore, when the shift force is applied to the reverse gear while the operation force is applied when the reverse gear is selected, one shift fork head for the forward gear performs a shift operation corresponding to the synchronization without being blocked by the sub head. become. Thereby, the input shaft and output shaft of a transmission can be synchronized at the time of reverse gear shift operation. After the reverse shift operation is completed, when the operation force in the reverse select direction disappears, the secondary head comes into contact with the interlock member, and the shift operation for the synchronization of one forward shift fork head is prevented. The In this way, it is possible to prevent the forward shift fork head from moving during reverse travel. Since the forward gear synchronizer does not function during traveling in the reverse gear as described above, the wear prevention effect of the synchro cone or the like of the forward gear synchronizer occurs, and the durability of the forward gear synchronizer It is possible to prevent a decline in sex.

JP 2007-327513 A (Claim 1, paragraphs [0010] to [0015])

  However, the reverse gear noise prevention transmission shown in the above-mentioned conventional Patent Document 1 requires a sub head, which increases the number of parts and has a problem in that a space for storing the sub head must be secured. .

On the other hand, in a range type multi-stage transmission in which the rotation speed of the main shaft of the main transmission can be changed in two steps of high speed or low speed by the sub-transmission, as shown in FIG. Of the strokes in the axial direction, the stroke S ₁ when switching between the main transmission and the sub-transmission is configured to be the same as the stroke S ₂ when switching only the main transmission. That is, a predetermined interval is provided in the axial direction of the select shift shaft so that the select shift lever 6 attached to each of the first to third gear shift shafts 5a to 5c is selectively engaged by moving in the axial direction of the select shift shaft. The first to sixth engaging pieces 7a to 7f are provided, and the select shift lever 6 is engaged before and after switching the main transmission and the sub-transmission among these engaging pieces 7a to 7f. The thickness t ₁ of the fifth engagement pieces 7b to 7e is formed to be the same as the thickness t _{2 of the} other engagement pieces 7a and 7f. As a result, when the driver tries to quickly operate the operation lever at the time of switching between the main transmission and the sub-transmission, a so-called oblique operation (FIG. 10A) is performed. There was a risk of simultaneous switching. For this reason, the synchro mechanism of the transmission is worn out, the sub-transmission stops at the neutral position where it cannot be switched to either the low speed side or the high speed side, or the sub transmission is switched from the low speed side to the high speed side. However, there is a possibility that a so-called overrun phenomenon that shifts down instead of upshifts may occur.

  An object of the present invention is to provide a range-type multi-stage transmission that can prevent wear of the synchro mechanism without increasing the number of parts, prevent the auxiliary transmission from stopping at the neutral position, and prevent the so-called overrun phenomenon. Is to provide.

The first aspect of the present invention is that, as shown in FIGS. 1, 4 and 9, at least the rotational speed of the main transmission 11 and the input to the main transmission 11 or the output from the main transmission 11 is increased. Alternatively, it is provided in parallel to the main shaft 17 of the main transmission 11 at a circumferential interval around the sub-transmission 13 that transmits the gear by shifting in two stages at low speed and the transmission gears 41 to 46 of the main transmission 11. A plurality of gear shift shafts 51 to 53 to which main shift forks 61 to 63 are respectively attached, and a select shift shaft 66 that is three-dimensionally intersected with the gear shift shafts 51 to 53, are moved in the axial direction of the select shift shaft 66 and rotated. In the range type multi-stage transmission including a select shift lever 67 that rotates in the direction, of the stroke of the select shift lever 67 in the axial direction of the select shift shaft 66, the main transmission 11 and the sub-change Stroke S ₁ at the time of switching of the machine 13, characterized in that it is configured to be longer than the main transmission 11 stroke S ₂ during switching only.

The second aspect of the present invention is an invention based on the first aspect, and further, as shown in FIGS. 1, 4 and 9, are attached to gear shift shafts 51 to 53, and a select shift lever 67 is a select shift. And a plurality of engagement pieces 71 to 76 arranged at predetermined intervals in the axial direction of the select shift shaft 66 so as to move in the axial direction of the shaft 66 and selectively engage. The thickness t ₁ of the engagement pieces 72 to 75 with which the select shift lever 67 engages before and after switching the main transmission 11 and the sub-transmission 13 among the combined pieces 71 to 76 is the same as that of the other engagement pieces 71 and 76. characterized in that it is thicker than the thickness t _2.

A third aspect of the present invention is an invention based on the second aspect, and further includes a select shift lever 67 before and after switching between the main transmission 11 and the sub-transmission 13, as shown in FIGS. When the thickness of the mating engagement pieces 72 to 75 is t ₁ and the thickness of the other engagement pieces 71 and 76 is t ₂ , t ₁ = (1.15 to 1.30) × t ₂ The thickness of each engagement piece 71 to 76 is set so as to satisfy the relationship.

  In the range-type multi-stage transmission according to the first aspect of the present invention, the stroke at the time of switching between the main transmission and the sub-transmission among the strokes of the select shift lever in the axial direction of the select shift shaft is determined only by the main transmission. Since it is configured to be longer than the stroke at the time of switching, the switching operation of the main transmission and the sub-transmission requires more time than the switching operation of only the main transmission. As a result, at the time of switching between the main transmission and the sub-transmission, even if the driver tries to operate the operation lever quickly, the driver does not perform the so-called oblique operation but performs the so-called crank-like operation that takes a relatively long time. become. Therefore, the phenomenon of simultaneous switching of the sub-transmission and the main transmission does not occur without increasing the number of parts, and the switching of the main transmission is performed after the switching of the sub-transmission is completed. The wear of the mechanism can be prevented, the auxiliary transmission can be prevented from stopping at the neutral position where neither the low speed side nor the high speed side is switched, and the sub transmission is switched from the low speed side to the high speed side. It is possible to prevent the so-called overrun phenomenon that shifts down instead of up.

(A) is a figure which shows a motion of an operation lever when changing the transmission gear of the range type multi-stage transmission of this embodiment to 1st-9th speed in order, (b) is a 5th speed change gear. It is a block diagram which shows the movement to a select lever and engagement when switching from speed to 6th stage speed. It is a schematic diagram showing a procedure for sequentially shifting the transmission gear from the first speed to the fourth speed by engaging the first or second select shift lever with the first to fourth engagement pieces. It is a schematic diagram showing a procedure for sequentially shifting the transmission gear from the fifth speed to the ninth speed by engaging the first or second select shift lever with the fifth to ninth engagement pieces. It is a principal part perspective view which shows the arrangement | sequence of a gear shift shaft and a select shift shaft, and the drive mechanism of a range rod. FIG. 5 is a cross-sectional view taken along line AA of FIG. 4 showing the movement of the range sensor when the range rod of the transmission is switched from the low speed side to the high speed side. FIG. 5 is a cross-sectional view taken along the line BB of FIG. 4 showing the movement of the select sensor when the select shift shaft of the transmission is switched from the low speed side to the high speed side. FIG. 6 is a cross-sectional view corresponding to FIG. 5 illustrating the movement of the range sensor when the range rod of the transmission is switched from the high speed side to the low speed side. FIG. 7 is a cross-sectional view corresponding to FIG. 6 illustrating the movement of the select sensor when the select shift shaft of the transmission is switched from the high speed side to the low speed side. It is a longitudinal cross-sectional block diagram of a main transmission and a subtransmission. (A) is a figure which shows the operation | movement of an operation lever when changing the transmission gear of the range type multistage transmission of a prior art example to 1st-9th speed in order, (b) is a figure from 5th speed. It is a block diagram which shows the movement to a selection lever and engagement at the time of switching to a 6th step speed.

  Next, an embodiment for carrying out the present invention will be described with reference to the drawings. As shown in FIG. 9, the range-type transmission 10 mounted on the truck has the number of shift stages of the main transmission 11 by a sub-transmission 13 provided on the surface of the main transmission 11 opposite to the clutch 12. This is a multi-stage transmission configured to be capable of shifting with twice the number of stages. The main transmission 11 is configured to be capable of shifting between the fifth forward speed and the first reverse speed, and the sub-transmission 13 is configured to be capable of shifting to a high speed or low speed second speed. As a result, the range type transmission 10 can shift between the ninth forward speed and the first reverse speed. The input shaft 14 is rotatably inserted into the clutch case 12a via the first bearing 21, the main shaft 17 is rotatably inserted into the main transmission case 16 via the second and third bearings 22 and 23, and An output shaft 19 is rotatably inserted into the auxiliary transmission case 18 via fourth and fifth bearings 24 and 25. The front end of the input shaft 14 is connected to the crankshaft via a clutch (not shown). The front end of the main shaft 17 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 17 and held by the fourth bearing 24. Thus, the main shaft 17 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 17. A counter shaft 33 is rotatably inserted into the main transmission case 16 through the sixth and seventh bearings 26 and 27 in parallel with the main shaft 17.

  On the other hand, above the first to fifth transmission gears 41 to 45 and the back transmission gear 46 of the main transmission 11, first to third gear shift shafts 51 to 53 are provided to the first to fifth transmission gears 41 to 45 and Circumferentially spaced apart and provided parallel to the main shaft 17 around the back transmission gear 46 (FIGS. 4, 6, 8, and 9). These gear shift shafts 51 to 53 are arranged in order of the first gear shift shaft 51, the second gear shift shaft 52, and the third gear shift shaft 53 from the right side (FIGS. 4, 6, and 8), and the first to third gear shift shafts. First to third main shift forks 61 to 63 are fitted to 51 to 53, respectively (FIGS. 4 and 9). Above the first to third gear shift shafts 51 to 53, there is provided a select shift shaft 66 that three-dimensionally intersects with the gear shift shafts 51 to 53 at right angles, and the select shift shaft 67 is provided with a select shift lever 67. Is attached (FIGS. 4, 6 and 8). The select shift lever 67 is non-rotatable with respect to the select shift shaft 66 and is fitted by serrations or splines (not shown) so as to be relatively movable in the axial direction. The select shift lever 67 includes a cylindrical tube portion 67a fitted in a predetermined position of the select shift shaft 66, and first and second lever portions 67b suspended from the tube portion 67a with an interval in the axial direction. , 67c. The end portions of these lever portions 67 b and 67 c are configured to enter between the first gear shift shaft 51 and the third gear shift shaft 53. Further, a power shift means (not shown) is connected to the end of the select shift shaft 66, and this power shift means switches the supply and discharge of compressed air with a power shift solenoid valve (not shown). By driving (not shown), rotation of the select shift shaft 66 and the select shift lever 67 is supported. 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, first to fifth engagement pieces 71 to 75 and a back engagement piece 76 are attached to the first to third gear shift shafts 51 to 53, respectively, and these engagement pieces 71 to 76 are all first gear shifts. It is arranged between the shaft 51 and the third gear shift shaft 53 (FIGS. 4, 6, 8, and 9). That is, the first to fifth engagement pieces 71 to 75 and the back engagement piece 76 are arranged in two rows with an interval in the axial direction of the gear shift shafts 51 to 53, and in the axial direction of the select shift shaft 66. Are arranged in three rows. The back engagement piece 76 and the first engagement piece 71 are attached to the first gear shift shaft 51, the second and third engagement pieces 72 and 73 are attached to the second gear shift shaft 52, and the fourth and fifth engagements. The combined pieces 74 and 75 are attached to the third gear shift shaft 53. Specifically, the back engagement piece 76 and the first engagement piece 71 are provided on the first boss portion 81 fitted to the first gear shift shaft 51, and are spaced apart in the axial direction of the first gear shift shaft 51. It is configured to open and project toward the select shift shaft 66. The second and third engagement pieces 72 and 73 are provided on the second boss portion 82 fitted to the second gear shift shaft 52, and are spaced apart in the axial direction of the second gear shift shaft 52 and engaged for back. The piece 76 and the first engagement piece 71 are adjacent to each other with a relatively wide space and project toward the select shift shaft 66. The fourth and fifth engagement pieces 74 and 75 are provided on a third boss portion 83 fitted to the third gear shift shaft 53, and are spaced apart in the axial direction of the third gear shift shaft 53 and are second and third. The engaging pieces 72 and 73 are adjacent to each other with a relatively narrow space, and project toward the select shift shaft 66.

  That is, the back engagement piece 76, the second engagement piece 72, and the fourth engagement piece 74 are provided side by side in the axial direction of the select shift shaft 66, and the first engagement piece 71, the third engagement piece 73, A fifth engagement piece 75 is provided side by side in the axial direction of the select shift shaft 66 (FIGS. 2 to 4, 6 and 8). The distance between the back engagement piece 76 and the first engagement piece 71, the distance between the second and third engagement pieces 72 and 73, and the distance between the fourth and fifth engagement pieces 74 and 75 are select shifts. The first and second lever portions 67b and 67c of the lever 67 are spaced apart from each other at their leading ends, and the select shift lever 67 moves in the axial direction of the select shift shaft 66 to move the first and second lever portions 67b, The distal end portion of 67c is configured to selectively engage with the first to fifth engagement pieces 71 to 75 and the back engagement piece 76.

The characteristic configuration of this embodiment is that, among the strokes of the select shift lever 67 in the axial direction of the select shift shaft 66, the stroke when switching between the main transmission 11 and the sub transmission 13 is only that of the main transmission 11. It is in the place where it became longer than the stroke at the time of switching (FIGS. 1, 4 and 9). That is, the thicknesses of the second to fifth engagement pieces 72 to 75 with which the select shift lever 67 engages before and after switching the main transmission 11 and the sub transmission 13 among the plurality of engagement pieces 71 to 76 are different. The engagement pieces 71 and 76 are thicker than the engagement pieces 71 and 76 (FIGS. 1B and 9). Specifically, the thickness of the second to fifth engagement pieces 72 to 75 with which the select shift lever 67 engages before and after switching between the main transmission 11 and the sub-transmission 13 is t ₁ , and the other engagement pieces When the thicknesses of 71 and 76 are t ₂ , the thicknesses of the engagement pieces 71 to 76 are set so as to satisfy the relationship of t ₁ = (1.15 to 1.30) × t ₂ . In addition, when the switching stroke of the main transmission 11 and the auxiliary transmission 13 is S ₁ and the switching stroke of only the main transmission 11 is S ₂ , S ₁ = (1.10 to 1.20) × each stroke is set so as to satisfy the relation of S _2. For example, when the thickness t ₂ of the other engagement pieces 71 and 76 is set to 8.0 mm, the thickness t ₁ of the second to fifth engagement pieces 72 to 75 is set to 9.7 mm. preferably, the main when the transmission 11 stroke S ₂ during switching only is set to 10.4 mm, the main transmission 11 and the stroke S ₁ at the time of switching of the sub transmission 13 to be set to 12.7mm Is preferred.

  On the other hand, the auxiliary transmission 13 includes a planetary gear mechanism 84 and an auxiliary sync mechanism 86 (FIG. 9). The planetary gear mechanism 84 includes a sun gear 84a that is fitted to the rear end portion of the main shaft 17, a large-diameter substantially bowl-shaped inner case 84b that is rotatably fitted to the output shaft 19, and a large diameter of the inner case 84b. A large-diameter internal gear 84c inserted on the inner surface of the portion, a substantially disc-shaped holding portion 84d provided at the front end portion of the output shaft 19, and a spacing in the circumferential direction between the holding portion 84d. A plurality of planetary gears 84f that are rotatably inserted into a plurality of pins 84e that are projected. The sub-synchronizing mechanism 86 includes a clutch hub 86a fitted to the small diameter portion of the inner case 84b and having an outer spline formed on the outer peripheral surface thereof, and an outer surface identical to the outer spline of the hub 86a fixed to the output shaft 19 on the outer peripheral surface. The high speed side clutch gear 86b formed with splines, the low speed side clutch gear 86c fixed to the auxiliary transmission case 18 and formed with the same outer spline as the outer splines of the hub 86a, and the outer splines of the hub 86a. An inner spline is formed, and a sleeve 86d is slidably fitted to the hub 86a so as to be movable in the axial direction of the main shaft 17 but not relatively rotatable with respect to the hub 86a, and the sleeve 86d is moved in the axial direction of the output shaft 19. The inner spline of the sleeve 86d is connected to the outer spline of the low speed side clutch gear 86c or the high speed side clutch gear 86b. And a meshing possible sub shift fork 86e.

  A single range rod 87 is provided around the planetary gear mechanism 84 in parallel with the output shaft 19, and the sub shift fork 86 e is attached to the range rod 87. The auxiliary transmission 13 is switched to the high speed side or the low speed side by the switching means 88 (FIGS. 4, 6, and 8). The switching means 88 includes an air cylinder 89 that drives the range rod 87 in the axial direction together with the auxiliary shift fork 86e, and low speed side and high speed side switching valves 91 and 92 that switch supply and discharge of compressed air to and from the air cylinder 89. Have. A piston 89a connected to the range rod 87 is slidably accommodated in the air cylinder 89, and the inside of the air cylinder 89 is partitioned into a high-speed side press-fit chamber 89b and a low-speed side press-fit chamber 89c by the piston 89a. The low-speed side and high-speed side switching valves 91 and 92 are 3-port 2-position switching electromagnetic valves. When the low speed side switching valve 91 is turned on, the air tank 90 and the low speed side press-fitting chamber 89c of the air cylinder 89 are communicated with each other. When the low speed side switching valve 91 is turned off, the low speed side pressurization chamber 89c is communicated with the atmosphere. The air tank 90 and the high-speed side press-fit chamber 89c of the air cylinder 89 are communicated with each other, and when the air tank 90 is turned off, the high-speed side press-fit chamber 89c is communicated with the atmosphere. In this embodiment, the air cylinder is exemplified as the driving device for driving the range rod in the axial direction. However, a hydraulic cylinder or other fluid pressure cylinder may be used.

  On the other hand, a substantially sector-shaped select convex portion 67d is provided on the right side portion of the upper surface of the cylindrical portion 67a of the select shift lever 67. The main shift case is arranged above the cylinder portion 67a of the select shift lever 67 at a predetermined interval from the upper surface of the cylinder portion 67a and arranged at a predetermined interval in the longitudinal direction of the select shift lever 67. A select sensor 94 including first and second select detectors 94 a and 94 b fixed to 16 is provided. The first and second select detecting portions 94a and 94b are first and second select cases 94c and 94d, and first and second select cases 94c and 94d that protrude from the select cases 94c and 94d toward the upper surface of the cylindrical portion 67a. Second plungers 94e and 94f are provided. When the select shift lever 67 moves relative to each shift fork in the axial direction of the select shift shaft 66, the select plungers 94e and 94f are configured to face or not face the select convex portion 67d. When the selection plungers 94e and 94f do not face the selection convex portion 67d, the selection plungers 94e and 94f protrude from the selection cases 94c and 94d, the selection detection portions 94a and 94b are turned off, and the selection plungers 94e and 94f are selected. When facing the convex portion 67d, the selector plungers 94e and 94f are pushed by the selector convex portion 67d to be pulled into the selector cases 94c and 94d, and the selector detectors 94a and 94b are turned on. . In this embodiment, the select convex portion is formed on the select shift lever. However, the select concave portion may be formed if there is no problem in the operation of the select sensor.

  The axial position and length of the select convex portion 67d, the axial positions of the first and second select detectors 94a and 94b, and the interval between the first and second select detectors 94a and 94b are the following low speed ranges. The position, the range switching position, and the high speed range position are set to exist. The low speed range position means that the select shift lever 67 moves relative to each shift fork in the axial direction of the select shift shaft 66, and the second lever portion 67c is between the first engagement piece 71 and the back engagement piece 76. The state in which the first lever 67b is located between the fourth engagement piece 74 and the fifth engagement piece 75 (FIGS. 2E and 3) from the state (FIGS. 2A and 2B). (A)) or the state in which the first lever 67b is positioned between the fourth engagement piece 74 and the fifth engagement piece 75 (FIG. 2 (e) and FIG. 3 (a)), the second lever portion 67c is The first select detection unit 94a is turned off and the second select detection unit 94b is turned off until the state (FIGS. 2A and 2B) located between the first engagement piece 71 and the back engagement piece 76. The position (FIG. 6 (a) and FIG.8 (c)) kept so that it turns on is said. Further, the range switching position means that the select shift lever 67 moves relative to each shift fork in the axial direction of the select shift shaft 66, and the first lever portion 67 b moves to the fourth engagement piece 74 and the fifth engagement piece 75. The state in which the second lever 67c is positioned between the second engagement piece 72 and the third engagement piece 73 (FIG. 3B and FIG. 3) from the state located in between (FIG. 2E and FIG. 3A). 3 (c)) or from the state where the second lever 67c is positioned between the second engagement piece 72 and the third engagement piece 73 (FIG. 3 (b) and FIG. 3 (c)). While the lever portion 67b is positioned between the fourth engagement piece 74 and the fifth engagement piece 75 (FIGS. 2E and 3A), the first select detection portion 94a is turned on and This refers to the position (FIG. 6B and FIG. 8B) where the second select detector 94b is turned on. Further, the high speed range position means that the select shift lever 67 moves relative to each shift fork in the axial direction of the select shift shaft 66, and the second lever portion 67 c moves to the second engagement piece 72 and the third engagement piece 73. The state in which the second lever 67c is positioned between the fourth engagement piece 74 and the fifth engagement piece 75 from the state positioned between them (FIGS. 3B and 3C) (FIGS. 3D and 3D). 3 (e)) or from the state where the second lever 67c is positioned between the fourth engagement piece 74 and the fifth engagement piece 75 (FIGS. 3 (d) and 3 (e)). Until the state (FIG. 3 (b) and FIG. 3 (c)) is located between the second engaging piece 72 and the third engaging piece 73, the first select detecting portion 94a is turned on and the second select detecting portion 94b. Refers to a position where FIG. 6C is kept off (FIG. 6C and FIG. 8A).

  On the other hand, as shown in detail in FIGS. 4, 5, and 7, the range rod 87 and the select shift shaft 66 are configured to three-dimensionally intersect, and a range recess 87 a is formed on the outer peripheral surface of the longitudinal center of the range rod 87. Is done. Above the range rod 87, the first and second range detections are fixed to the auxiliary transmission case 18 in the longitudinal direction of the range rod 87, with a predetermined interval from the upper surface of the range rod 87. A range sensor 93 including parts 93a and 93b is provided. The first and second range detectors 93a and 93b include first and second range cases 93c and 93d, and first and second range cases 93c and 93d that project from the range cases 93c and 93d toward the side surface of the range rod 87. It has second range plungers 93e, 93f. When the range rod 87 moves in the axial direction, the range plungers 93e and 93f are configured to face or not face the range recess 87a. When the range plungers 93e and 93f are not opposed to the range recess 87a, the range plungers 93e and 93f are pushed by the outer peripheral surface of the range rod 87 to be pulled into the range cases 93c and 93d, and the range detection units 93a and 93b are turned on. Thus, when the range plungers 93e and 93f face the range recess 87a, the range plungers 93e and 93f protrude from the range cases 93c and 93d into the range recess 87a so that the range detection units 93a and 93b are turned off. Composed. In this embodiment, the range concave portion is formed in the range rod, but the range convex portion may be formed.

  An operation lever (not shown) that is operated by the driver to switch the transmission 10 to the ninth forward speed position or the reverse position is provided in the driver seat of the truck, and this lever is in the neutral position. There is provided a neutral switch 96 which is turned on when positioned at. The detection outputs of the neutral switch 96, the first select detection unit 94a, the second select detection unit 94b, the first range detection unit 93a, and the second range detection unit 93b are connected to the control input of the controller 97, and the control output of the controller 97 Are connected to the low speed side switching valve 91, the high speed side switching valve 92, and the power shift solenoid valve. The controller 98 has moved the select shift lever 67 from the state where the select shift lever 67 is positioned at the gear position immediately before the sub transmission 13 is switched to the gear position position after the sub transmission 13 is switched. Is detected by the select sensor 94, the drive device 89 is driven based on the displacement of the select shift lever 67 detected by the select sensor 94. That is, the controller 98 determines whether the first and second select detectors 94a and 94b are in a state where either one of the first or second select detectors 94a and 94b of the select sensor 94 is on and the other is off. When both are turned on, the auxiliary transmission 13 is configured to be recognized as a switching displacement. Note that the controller is configured such that when both the first and second select detection units are turned off from the state where either the first or second select detection unit of the select sensor is on and the other is off. The auxiliary transmission may be recognized as a displacement at the time of switching.

When the driver is operating the control lever between the first speed position on the low speed side to the fifth speed position or to the reverse position, as shown in FIGS. 5 (a), 7 (c), and 9 In addition, the sleeve 86d of the auxiliary sync mechanism 86 is maintained in a state where the clutch hub 86a and the low speed side clutch gear 86c are connected, and the inner case 84b and the internal gear 84c are fixed to the auxiliary transmission case 18, so that the main shaft 17 Is reduced at a predetermined reduction ratio (Z ₁ / (Z ₁ + Z ₂ ), Z ₁ : number of teeth of the sun gear 84 a, Z ₂ : number of teeth of the internal gear 84 c) and transmitted to the output shaft 19. Configured to be When the driver operates the operation lever between the sixth speed position and the ninth speed position, as shown in FIGS. 5C and 7A, the sleeve 86d of the auxiliary sync mechanism 86 is provided. Is maintained in a state in which the clutch hub 86a and the high speed side clutch gear 86b are connected, and the inner case 84b and the output shaft 19 are fixed to each other and rotate at the same rotational speed, so that the rotational speed of the main shaft 17 is kept the same. It is configured to be transmitted to the output shaft 19 as it is.

  Returning to FIG. 9, 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 17, and a fifth transmission that is fixed to the rear end of the main shaft 11. A first synchronization mechanism 111 provided between the gear 45, the first to fifth counter gears 101 to 105 and the back counter gear 106 fixed to the counter shaft 33, and the first transmission gear 41 and the back transmission gear 46. And a second synchronization mechanism 112 provided between the second transmission gear 42 and the third transmission gear 43, and a third synchronization mechanism 113 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 17 via the eighth to eleventh bearings 28 to 31, and the back transmission gear 46 is rotatably fitted to the main shaft 17 via the twelfth bearing 32. The first to fifth transmission gears 41 to 45 mesh with the first to fifth counter gears 101 to 105, respectively. The back transmission gear 46 and the back counter gear 106 are idle gears (not shown) fixed to the idle shaft. Z)). Since the first to third sync mechanisms 111 to 113 are configured substantially the same, the first sync mechanism 111 will be described as a representative, and the description of the second and third sync mechanisms 112 and 113 will be omitted. The first sync mechanism 111 is fitted to the rear portion of the main shaft 17 and has an outer spline formed on the outer peripheral surface thereof. The first sync mechanism 111 is fixed to the first transmission gear 41 and has the same outer spline as the hub 111a on the outer peripheral surface thereof. The first clutch gear 111b having the outer spline formed thereon, the back clutch gear 111c fixed to the back transmission gear 46 and having the same outer spline as the outer spline of the hub 111a, and the outer spline of the hub 111a An inner spline that meshes with the hub 111a is movably fitted in the axial direction of the main shaft 17 and loosely fitted to the hub 111a so as not to rotate relative to the hub 111a. The inner spline of the first sleeve 111d is moved in the axial direction of the first clutch gear 111b or the bar. And a first main shift fork 61 which can mesh with the outer splines of the click clutch gear 111c. Between the first clutch hub 111a and the first clutch gear 111b, or between the first clutch hub 111a and the back clutch gear 111c, the first sleeve 111d and the first clutch gear 111b or the back clutch gear 111c Each of them is provided with a known synchronizer ring (not shown) for smooth engagement.

  The operation of the range type transmission 10 configured as described above will be described. When the truck is traveling at any one of the first speed to the fifth speed, the neutral switch 96 is turned off, the first select detector 94a is turned off, the second select detector 94b is turned on, and the first The range detector 93a is turned off, and the second range detector 93b is turned on (FIGS. 5A and 6A). Further, as shown in FIGS. 5A and 9, the auxiliary transmission 13 is maintained in a state in which the sleeve 86d of the auxiliary sync mechanism 86 is connected to the clutch hub 86a and the low-speed clutch gear 86c. Since the internal gear 84 c is fixed to the auxiliary transmission case 18, the rotational speed of the main shaft 17 is reduced at a predetermined reduction ratio and transmitted to the output shaft 19.

  When the operation lever is operated to the neutral position in order to shift up from this state to the sixth to ninth gears on the high speed side, for example, the sixth gear, the neutral switch is turned on. The select shift lever passes the range switching position. That is, the select shift lever 67 moves relative to each shift fork in the axial direction of the select shift shaft 66, and the first lever portion 67b is positioned between the fourth engagement piece 74 and the fifth engagement piece 75. From FIGS. 2 (e) and 3 (a), the second lever 67c is positioned between the second engaging piece 72 and the third engaging piece 73 (FIG. 31 (b) and FIG. 3 (c)). Until the first select detector 94a is turned on and the second select detector 94b is turned on (FIG. 6B). When this range switching position is passed, the controller 97 turns on the high speed side switching valve 92 and turns off the power shift solenoid valve. As a result, the compressed air in the air tank 90 flows into the high speed side press-fitting chamber 89b of the air cylinder 89, the range rod 87 moves in the direction of the solid line arrow in FIG. 5A, and reaches the position in FIG. The first and second range detectors 93a and 93b are turned off, and the range rod 87 is further moved in the direction of the solid line arrow in FIG. 5B to reach the position in FIG. 5C. Range detectors 93a and 93b are turned on. In this state, the sleeve 86d of the auxiliary sync mechanism 86 connects the clutch hub 86a and the high speed side clutch gear 86b, and the inner case 84b and the output shaft 19 are fixed to each other and rotate at the same rotational speed. The speed is not reduced but transmitted to the output shaft 19 while maintaining the same rotational speed.

  Thereafter, when the second lever portion 67c of the select shift lever 67 reaches between the second engaging piece 72 and the third engaging piece 73, the second select detecting portion 94b of the select sensor 94 is turned off. As a result, the controller 97 turns off the high-speed side switching valve 92 and turns on the power shift solenoid valve. As a result, the compressed air in the high-speed side press-fitting chamber 89b of the air cylinder 89 is discharged into the atmosphere, and the driver's operation to the sixth speed stage is supported by the power shift means. Easy operation. In this embodiment, when the second select detection unit 94b is turned off (FIG. 6C), the controller 97 determines that the switching of the auxiliary transmission 13 is completed and turns off the high-speed side switching valve 92. However, when both the first and second range detectors 93a and 93b are turned on (FIG. 5C), the controller 97 determines the completion of switching of the auxiliary transmission 13, and turns off the high-speed side switching valve 91. May be.

Here, the thicknesses of the second to fifth engagement pieces 72 to 75 with which the select shift lever 67 is engaged before and after switching between the main transmission 11 and the sub transmission 13 are changed to the thicknesses of the other engagement pieces 71 and 76. By forming it thicker than this, the stroke S ₁ of the select shift lever 67 when shifting up from the fifth low gear on the low speed side to the sixth high gear on the high speed side (when the main transmission 11 and the sub-transmission 13 are switched). Since the stroke S ₁ ) of the select shift lever 67 is configured to be longer than the stroke S ₂ when only the main transmission 11 is switched, the switching operation of the main transmission 11 and the sub-transmission 13 is performed in the main transmission. It takes more time than only 11 switching operations. As a result, at the time of shifting up from the fifth speed to the sixth speed (when the main transmission 11 and the sub-transmission 13 are switched), even if the driver tries to operate the operation lever quickly, FIG. ), Since the straight portion is provided, a so-called oblique operation is not performed, and a relatively time-consuming crank-like operation is performed. Accordingly, the phenomenon of simultaneous switching of the sub-transmission 13 and the main transmission 11 does not occur, and the switching of the main transmission 11 is performed after the switching of the sub-transmission 13 is completed as described above. The first to third synchronization mechanisms 111 to 113 and the auxiliary synchronization mechanism 86 can be prevented from being worn, and the auxiliary transmission 13 can be prevented from stopping at the neutral position where the low speed side and the high speed side are not switched. Further, it is possible to prevent a so-called overrun phenomenon in which the sub-transmission 13 is not switched from the low speed side to the high speed side but is not shifted up but down.

  On the other hand, when the truck is traveling at any one of the sixth speed to the ninth speed, the neutral switch is turned off, the first select detector 94a is turned on, the second select detector 94b is turned on, The first range detector 93a is turned on, and the second range detector 93b is turned off (FIGS. 7A and 8A). Further, as shown in FIG. 7A, the auxiliary transmission 13 maintains the sleeve 86d of the auxiliary sync mechanism 86 in a state where the clutch hub 86a and the high speed side clutch gear 86b are connected, and the inner case 84b and the output shaft 19 are connected. Are fixed to each other and rotating at the same rotational speed, the rotational speed of the main shaft 17 is transmitted to the output shaft 19 while being kept at the same rotational speed without being decelerated.

  When the operation lever is operated to the neutral position in order to shift down from this state to the first to fifth gears on the low speed side, for example, the fifth gear, the neutral switch 96 is turned on. Then, the select shift lever 67 passes through the range switching position. That is, the select shift lever 67 moves relative to each shift fork in the axial direction of the select shift shaft 66, and the second lever 67c is positioned between the second engagement piece 72 and the third engagement piece 73 ( 3 (b) and 3 (c)), the first lever portion 67b is located between the fourth engagement piece 74 and the fifth engagement piece 75 (FIG. 2 (e) and FIG. 3 (a)). Until the first select detector 94a is turned on and the second select detector 94b is turned on (FIG. 8B). After passing this range switching position, the controller 97 turns on the low-speed side switching valve 91 and turns off the power shift solenoid valve. As a result, the compressed air in the air tank 90 flows into the low speed side press-fitting chamber 89c of the air cylinder 89, the range rod 87 moves in the direction of the solid line arrow in FIG. 7A, and reaches the position in FIG. The first and second range detectors 93a and 93b are turned off, and the range rod 87 is further moved in the direction of the solid line arrow in FIG. 7B to reach the position in FIG. 7C. Range detectors 93a and 93b are turned on. As a result, the sleeve 86d of the auxiliary sync mechanism 86 connects the clutch hub 86a and the low speed side clutch gear 86c, and the inner case 84b and the internal gear 84c are fixed to the auxiliary transmission case 18, so that the rotational speed of the main shaft 17 is predetermined. And is transmitted to the output shaft 19.

  Thereafter, when the first lever portion 67b of the select shift lever 67 reaches between the fourth engaging piece 74 and the fifth engaging piece 75, the first select detecting portion 94a of the select sensor 94 is turned off. As a result, the controller 97 turns off the low speed side switching valve 91 and turns on the power shift solenoid valve. As a result, the compressed air in the low-pressure side press-fitting chamber 89c of the air cylinder 89 is discharged into the atmosphere and the driver's operation to the fifth speed stage is assisted by the power shift means. Easy operation. As described above, at the time of shifting accompanied by switching of the sub-transmission 13, the sub-transmission 13 is quickly switched in response to the operation of the operation lever, so that the range type transmission 10 can be shifted quickly.

Here, the thicknesses of the second to fifth engagement pieces 72 to 75 with which the select shift lever 67 is engaged before and after switching between the main transmission 11 and the sub transmission 13 are changed to the thicknesses of the other engagement pieces 71 and 76. By forming it thicker than this, the stroke S ₁ of the select shift lever 67 when shifting down from the sixth speed on the high speed side to the fifth speed on the low speed side (when the main transmission 11 and the sub-transmission 13 are switched) Since the stroke S ₁ ) of the select shift lever 67 is configured to be longer than the stroke S ₂ when only the main transmission 11 is switched, the switching operation of the main transmission 11 and the sub-transmission 13 is performed in the main transmission. It takes more time than only 11 switching operations. As a result, at the time of downshift from the sixth speed to the fifth speed (when the main transmission 11 and the sub-transmission 13 are switched), even if the driver tries to operate the operation lever quickly, FIG. ), Since the straight portion is provided, a so-called oblique operation is not performed, and a relatively time-consuming crank-like operation is performed. Accordingly, the phenomenon of simultaneous switching of the sub-transmission 13 and the main transmission 11 does not occur, and the switching of the main transmission 11 is performed after the switching of the sub-transmission 13 is completed as described above. The first to third synchronization mechanisms 111 to 113 and the auxiliary synchronization mechanism 86 can be prevented from being worn, and the auxiliary transmission 13 can be prevented from stopping at the neutral position where the low speed side and the high speed side are not switched. Further, it is possible to prevent a so-called overrun phenomenon in which the sub-transmission 13 is not switched from the low speed side to the high speed side but is not shifted up but down.

  In the above embodiment, the truck is exemplified as the vehicle equipped with the range type transmission of the present invention. However, a bus or other vehicles may be used. In the above embodiment, two lever portions are provided on the select shift lever, but one lever portion may be provided on the select shift lever. In this case, it is necessary to provide 10 engaging pieces (2 rows × 5 pieces) when assuming 9 steps forward and 1 step backward. Moreover, in the said embodiment, although the air cylinder was mentioned as a fluid pressure cylinder, you may use a hydraulic cylinder. In the above embodiment, the auxiliary transmission is provided on the surface opposite to the clutch mounting surface of the main transmission. However, the auxiliary transmission may be provided between the clutch and the main transmission. In this case, the sub-transmission is configured to change the rotational speed of the crankshaft of the engine in two stages, high speed and low speed, and transmit it to the main shaft. In the above embodiment, the sub-transmission is constituted by the planetary gear mechanism and the sub-synchronizing mechanism. However, the counter shaft is provided to extend rearward, and gears are respectively attached to the rear portion and the output shaft of the counter shaft. You may comprise by the gear mechanism and sub-synchronization mechanism which obtain a reduction ratio. Further, in the above embodiment, the transmission is configured to be capable of shifting to the 9th forward speed and the first reverse speed, but the transmission can be configured to be capable of shifting to the 13th forward speed and the first reverse speed. May be configured with 8 forward speeds and 2 reverse speeds, or the transmission may be configured with 12 forward speeds and 2 reverse speeds, and further equipped with 5 gear shift shafts and the transmission is 16 forward speeds. Alternatively, it may be configured as a second reverse speed, or six or more gear shift shafts may be provided to further increase the number of transmission stages.

DESCRIPTION OF SYMBOLS 10 Range type transmission 11 Main transmission 13 Subtransmission 17 Main shaft 19 Output shaft 41-46 Transmission gear 51-53 Gear shift shaft 61-63 Main shift fork 66 Select shift shaft 67 Select shift lever 71-76 Engagement piece

Claims (3)

A main transmission (11) and a sub-transmission that transmits the rotational speed of the input to the main transmission (11) or the output from the main transmission (11) by shifting it to at least two stages of high speed and low speed ( 13) and a main shift fork provided parallel to the main shaft (17) of the main transmission (11) with a circumferential interval around the transmission gear (41 to 46) of the main transmission (11) A plurality of gear shift shafts (51 to 53) to which (61 to 63) are respectively attached, and a select shift shaft (66) that is three-dimensionally intersected with the gear shift shaft (51 to 53). ) In the range-type multi-stage transmission equipped with a select shift lever (67) that moves in the axial direction and rotates in the rotational direction.
Of the strokes in the axial direction of the select shift shaft (66) of the select shift lever (67), the stroke (S ₁ ) at the time of switching between the main transmission (11) and the sub-transmission (13), A range-type multi-stage transmission configured to be longer than a stroke (S ₂ ) at the time of switching only the main transmission (11). The select shift shaft (66) is attached to the gear shift shaft (51-53), so that the select shift lever (67) moves in the axial direction of the select shift shaft (66) and selectively engages. A plurality of engagement pieces (71 to 76) arranged at predetermined intervals in the axial direction;
Among the plurality of engagement pieces (71 to 76), engagement pieces (73 to 76) with which the select shift lever (67) is engaged before and after switching the main transmission (11) and the sub transmission (13). the thickness of) (t ₁₎ is the thickness of the other engaging piece (71,72) (t ₂₎ than the thick claims 1 range multistage transmission according. The main transmission (11) and the thickness of the engaging piece of the select shift lever before and after switching the auxiliary transmission (13) (76) is engaged (72-75) and t _1, other engagement when the thickness of the strip (71, 76) and _{t 2, t 1 = (1.15~1.30} ) thickness of the respective engagement pieces (71 to 76) so as to satisfy the relationship × t ₂ is The range type transmission according to claim 2, wherein the range type transmission is set.

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