JP3095834B2 - Transmission mis-shift prevention structure - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a structure in which a misshift preventing means for restricting the operation of a shift system so as to prevent an improper shift operation is incorporated in a transmission.

[0002]

2. Description of the Related Art In general, a manual type transmission is provided with a plurality of gear trains for speed change arranged on a main shaft, a counter shaft and the like, and a power transmission between one gear of each gear train and a shift. It is provided with a synchronizing device for performing intermittent operation, and a shift system such as a shift rod for operating the synchronizing device in response to operation of a shift operation unit such as a change lever.

This type of transmission is provided with a misshift prevention means for restricting the movement of the shift system in order to prevent a situation such as a shift from overdrive to reverse due to an erroneous shift operation during traveling. Is known. For example, 55-103158
In the publication, a rear end of a fork rod is connected to a lower end of a change lever, and one of a plurality of forks corresponding to the synchronization device is moved by an operation of a fork rod linked to the change lever. For the shift system, a misshift prevention means such as a cam for restricting the movement of the change lever so as to prevent the shift from the fifth speed to the reverse is attached to a plug provided in the mounting portion of the change lever. The structure is shown.

[0004]

According to the structure disclosed in the above publication, the portion where the mis-shift preventing means is attached to the plug protrudes outward from the change lever mounting portion behind the transmission case. Therefore, an extra space is taken outside the change lever mounting portion, and a problem remains in terms of downsizing and the like. As another conventionally known misshift prevention structure, there is a structure in which a member constituting a misshift prevention means is attached to a transmission case. However, according to such a structure, a gear train is provided in the transmission case. In addition to the work of incorporating the shift system and the like, it is necessary to attach a misshift prevention means to the transmission case, and the workability is poor.

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and provides a structure for preventing a misshift of a transmission in which the misshift preventing means can be compactly incorporated in a transmission case and can be easily assembled. With the goal.

[0006]

According to the present invention, in order to achieve the above object, the rotation of an input shaft is provided inside a transmission case.
The transmission is transmitted through the gears for
That a main shaft, a base <br/> bearings for supporting the main shaft, the transmission is provided a bearing fixing member for fixing the bearing to the transmission case, the shift
Controls that rotate and slide in conjunction with the operation unit
Place the rod parallel to the main shaft and
One piece for both the troll rod and the main shaft
Hold the shift fork on the side of the
Multiple shift rods that can be disengaged from
The control rod and main shaft
On both sides of the shaft, on the side opposite to the shift rod.
The bearing fixing member is provided with misshift prevention means for restricting the movement of the shift system so as to prevent improper shift operation of the control rod .

In this configuration, the above-mentioned hand for preventing misshift is provided.
The step faces the bearing fixing member and the control rod.
And a cam holding projection formed so as to project
The rod is formed with a protrusion toward the cam holding protrusion.
It is preferable to provide a projecting piece .

[0008]

According to the above construction, the misshift preventing means is incorporated into the transmission case without protruding outward. At the time of assembling the transmission, the transmission is mounted on the transmission case in a state where the mis-shift preventing means is previously attached to the bearing fixing member.

[0009]

An embodiment of the present invention will be described with reference to the drawings.
FIGS. 1 to 4 show an example of a transmission to which the present invention is applied. In these figures, reference numeral 1 denotes a transmission case also serving as a clutch housing, which is divided in advance into two parts, a front case 11 and a rear case 12. Are connected by a plurality of bolts 13 in a state where they are brought together by the respective flange portions 110 and 120. The transmission case 1 shown in the figure has a generally cone shape narrowing toward the rear side, and is formed in a cylindrical shape having a substantially constant cross section only in a predetermined range of an intermediate portion including a mating portion of the front and rear cases 11 and 12, A bolt boss 14 is formed in the cylindrical portion. Inside the transmission case 1, a transmission 2 including members such as an input shaft 21, a main shaft 22, and a counter shaft 23, and a clutch 3 located in front of the transmission 2 are housed. Various attachment mechanisms such as a reverse misshift prevention mechanism 60 described later are arranged inside the cylindrical portion.

The front case 11 integrally includes a clutch housing 111 and a transmission housing 112, and a bearing 115 for the input shaft 21 and the counter shaft 23 is provided at a front portion of the transmission housing 112 in the front case 11. , 116
And the front cover 15 and the collar member 16 located in front of the
Installed in. On the other hand, within the rear case 12, bearings 121 and 122 for the main shaft 22 and the counter shaft 23 are provided, and a bearing cover 17 as a bearing fixing member is disposed in front of the bearing 121. The bearing cover 17 is attached to the rear case 17 by bolts 170. A bush 17 for rotatably supporting a sliding yoke is fitted to the rear end of the rear case 12, and oil scraped up by gears 236 and 226 is An oil passage 19 leading to a sliding yoke support portion 18 is formed.

The transmission 2 has an input shaft 21 connected to an engine output shaft (not shown) via the clutch 3, and a sliding yoke at the end of a propeller shaft (not shown) connected to the rear end of the main shaft 22. The input shaft 21 and the main shaft 22 are arranged in a straight line back and forth, and are rotatably connected to each other via a bearing.
Reference numeral 3 is arranged below and parallel to the main shaft 22. These are the bearings 115, 11
The transmission case 1 is rotatably supported on the transmission case 1 via the gears 6, 121, 122.

At the rear end of the input shaft 21, a drive gear 210 is provided. The counter shaft 23 is provided with a counter drive gear 23 in order from the front side.
0, counter third gear 231, counter second gear 2
32, a counter first speed gear 233 and a counter reverse gear 234 constituted by a common tooth portion 235, and a counter overdrive gear 236, and the counter drive gear 230 is connected to the drive gear 21 of the input shaft 21.
By engaging with 0, the counter shaft 23 is interlocked with the input shaft 21.

The main shaft 22 includes a third-speed / fourth-speed synchronizer 24, a third-speed gear 221, a second-speed gear 222, a first-second-speed synchronizer 25, a first-speed gear 223,
A reverse gear 224, an overdrive-reverse synchronizer 26, and an overdrive gear 226 are provided. Each of the gears 221 to 224, 226 is rotatably mounted on the main shaft 22. Each of the synchronizers 24-26 has a sleeve 24a, 25a, 26a which slides in accordance with the operation of shift rods 41-43 described later.
When the sleeve slides forward, the front gear of the synchronizer (the input shaft 2 in the case of the synchronizer 24 for the third and fourth speeds) is used.
1) is connected to the main shaft 22, and when the sleeve slides rearward, the gear behind the synchronizer is connected to the main shaft 22, and when the sleeve is in the neutral position, the gears on the front and rear sides and the main shaft 22 are not connected. It is configured so that

The third gear 221, the second gear 222,
The speed gear 223 and the overdrive gear 226 are respectively gears 231 and 23 of the counter shaft 23.
2,233,236. The reverse gear 224 is linked to a counter reverse gear 234 via first and second idle gears 271 and 272 provided on the idle shaft 27. The idle shaft 27 has an attached portion 273 at the rear end attached to the rear case 12 by bolts 28. A spline 228 for connecting a sliding yoke is formed on the rear side of the main shaft 22.

A control rod 40 is mounted above the transmission case 1, and first, second, and third shift rods 41, 42, and 43 are provided.
These constitute a shift system. The control rod 40 is disposed above the cylindrical portion of the transmission case 1 and has a rear end protruding outside the cone-shaped portion of the rear case 12. This rear end is connected to a change lever (not shown) via a link 401. By doing so, the control rod 40 rotates and slides according to the selection and shift operation of the change lever. Further, on both sides of the link 401, connecting members 404 for connecting the change lever holding portion and the transmission case 1 to prevent unnecessary swing of the change lever and the like are arranged,
The transmission-side end of this connecting member 404 is attached to a bracket 405 jointly fastened with bolts 13 for connecting the front and rear cases 12, a pivot 406 and a rubber bush 407.
Are coupled through.

Each of the shift rods 41 to 43 is
The rear part is slidably supported by the subframe 45 in the rear case 12 and the front part is formed integrally with the front case 11 in a state of being arranged on one side of the control rod 40 and being parallel to each other. The front part is slidably supported by the shift rod support part 118 (see FIG. 5). A select engagement piece 40a protrudes from the control rod 40, and a select gate 41a,
42a and 43a are provided, and the control rod 4
The engagement piece 40a is selectively engaged with one of the select gates 41a, 42a, 43a in accordance with the 0 rotation position. In addition, each shift rod 41
43 are provided with shift forks 41b, 42b, 43b which engage with the sleeves 24a, 25a, 26a of the synchronizers 24 to 26 disposed on the main shaft 22.

The sub frame 45 is fixed to the rear case on both sides by bolts (not shown). FIG.
As shown in FIG. 7, the sub-frame 45 includes a spring 53 and a ball 54 housed in a detent mechanism housing 52, and corrugated irregularities 51 formed on the shift rods 41 to 43. A detent mechanism 50 for giving a feeling of movement is provided, and an interlock mechanism for preventing simultaneous operation of a plurality of shift rods is provided.

A reverse miss-shift prevention mechanism 60 is provided for the shift system such as the control rod 40 or the like. This reverse misshift prevention mechanism 60
Is provided to prevent a misshift from overdrive to reverse, and as will be described in detail later, a projecting piece 61 is continuously provided at a predetermined position of the control rod 40, while a bearing 121 for supporting a rear portion of the main shaft 22 is provided. The front bearing cover 17 is provided with a misshift prevention means including a cam 64 and the like. The location of the misshift prevention means in the bearing cover 17 is on the side opposite to the shift rods 41 to 43 with respect to the control rod 40 (see FIG. 4 ). That is, the control rod 40
Is arranged in parallel with the main shaft 22,
Both the control rod 40 and the main shaft 22
Shift rods 41 to 43 on one side
Are arranged, and the bearing cover 17 is provided on the opposite side.
Are provided with misshift prevention means. In FIG. 3, reference numeral 80 denotes a select return mechanism that returns the shift system to the basic position when in neutral. On both sides of the control rod 40, a return piston 82 and a spring 83 housed in a return member housing portion 81 of the rear case 12; The claw 85 is connected to the control rod 40 and abuts against the lower end of the piston 82. The control rod 40 is returned to an intermediate position in the rotation range by the urging force of the spring 83 in neutral.

FIGS. 6 to 8 show a specific structure of the reverse misshift prevention mechanism 60. FIG. In these drawings, the bearing cover 17 has a plurality of bolt bosses 17a at a plurality of locations around its periphery, and a bolt 170 fastened to the bolt boss 17a through the rear case from the rear in a state positioned in front of the bearing 121. Is fixed to the rear case.

A cam holding projection 62 is provided continuously above the periphery of the bearing cover 17 at a position below the control rod 40, and near the upper end of the projection 62, a front and a side. A notch 63 is formed in the notch 63.
4 are attached. This misshift prevention cam 64
Is rotatably supported by a pivot 65,
Is inserted into a vertical hole formed in the projecting portion 62 and is fixed by a spring pin 67. Further, a return spring 66 for elastically holding the misshift preventing cam 64 in a predetermined reference position in the rotation range, is mounted on the pivot shaft 65 in a state of engaging with the cam 64, further of the cut section 63 The mis-shift prevention cam 6
A stopper portion 68 for restricting the rotation range of the shutter 4 is formed.

The tip of the misshift preventing cam 64 projects laterally from the notch 63 of the cam holding projection 62, and the control rod 40 is positioned at one end of its rotation range at an overdrive-reverse select position. , The positional relationship is set so that the protruding piece 61 of the control rod and the tip of the cam 64 for preventing misshift correspond to each other. Thus, the reverse miss shift prevention mechanism 60 is configured.

According to the transmission of this embodiment as described above,
When the control rod 40 is rotated and slid according to the operation of the change lever select direction and the shift direction (not shown), the gear is selectively operated by the synchronizer via the shift rod. When the shift operation is erroneously performed to the reverse side from the state of FIG.
Blocked by 0. That is, as shown in FIG. 8, when the control rod 40 slides from the overdrive shift position to the reverse shift position (arrow a), the misshift prevention cam 64 causes the protrusion 61 to move.
To rotate (arrow b), and the cam 6
When the wheel 4 rotates to a certain extent, it comes into contact with the stopper portion 68 to prevent further rotation, thereby preventing the shift to reverse. When the control rod 40 rotates in the neutral state and the select position changes, the protruding piece 61 separates from the cam 64, and the cam 64 returns to the reference position (arrow c). At the time of the reverse shift operation, the shift operation is performed without being hindered by the cam 64.

The means for preventing misshift such as the cam 64 is
Since the bearing cover 17 is provided inside the transmission case 1, no extra space is taken outside the transmission case 1.
Is arranged on the side opposite to the shift rod with respect to the transmission case 1 so as to be compactly assembled in the transmission case 1. Further, when assembling the transmission, a sub-assembly for preventing misshift is previously provided on the bearing cover 17 and the bearing cover 17 is attached to the transmission case 1.
, The misshift preventing means can be easily assembled.

[0024]

As described above, according to the present invention, since the bearing fixing member for fixing the bearing for supporting the rotary shaft of the transmission inside the transmission case to the transmission case is provided with the means for preventing misshift, It is possible to compactly provide the misshift prevention means without taking extra space outside the machine, and to assemble the transmission by assembling the misshift prevention means to the bearing fixing member in advance when assembling the transmission. Can be simplified.

Further, the control rod and the main
Multiple shift locks on one side of both shafts
The bearings in parallel, and place the bearings on the opposite side.
Since the fixing member is provided with the misshift prevention means, the shift rod and the misshift prevention means can be arranged compactly inside the transmission case.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view of an entire transmission according to an embodiment of the present invention.

FIG. 2 is a partially sectional plan view of the transmission.

FIG. 3 is a sectional view taken along line III-III in FIG. 1;

FIG. 4 is a sectional view taken along the line IV-IV in FIG. 1;

FIG. 5 is a cross-sectional view of a shift rod arrangement portion.

FIG. 6 is a partially enlarged side view of a portion provided with a misshift prevention mechanism.

FIG. 7 is an enlarged partial cross-sectional front view of a portion provided with a misshift prevention mechanism.

FIG. 8 is an enlarged partial cross-sectional plan view of a portion provided with a misshift prevention mechanism.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Transmission case 2 Transmission 22 Main shaft 121 Bearing 17 Bearing cover 40 Control rod 41-43 Shift rod 60 Misshift prevention mechanism

Claims (2)

(57) [Claims] 1. The rotation of an input shaft is provided inside a transmission case.
The transmission is transmitted by being shifted through a gear for shifting.
The main shaft that rotates and the main shaft
In a transmission provided with a bearing and a bearing fixing member for fixing the bearing to a transmission case, a control that rotates and slides in conjunction with a shift operation unit is provided.
Place the roll rod parallel to the main shaft and attach it to both the control rod and the main shaft.
Hold the shift fork on one side
Multiple shift rods that can be disengaged from the control rod
Are arranged in parallel, and both the control rod and the main shaft are
On the side opposite to the shift rod, the bearing
A mis-shift preventing structure for a transmission , wherein a fixing member is provided with a mis-shift preventing means for restricting movement of a shift system so as to prevent an improper shifting operation of a control rod . 2. The apparatus according to claim 1, wherein said misshift preventing means includes a bearing.
The fixing member protrudes toward the control rod.
With a cam retaining projection, and the control rod
The misshift prevention structure for a transmission according to claim 1, further comprising a projection formed to project toward the cam holding projection .