JPH0444A - Gear type transmission - Google Patents

Abstract

PURPOSE:To connect two clutches smoothly at the time of connecting each gear to an input shaft and an output side shaft freely to disconnect by engaging a synchronous engagement type clutch after engaging a dog clutch. CONSTITUTION:When a shift fork 16 is moved to the right side, a first clutch 40 is engaged, and a second clutch 50 is engaged with a reverse gear device side. As a result a reverse input gear 6 is locked with a counter shaft 3, and a reverse output gear 7 is locked with a main shaft 2 to transmit the power reversely. At this stage, since a reverse side clearance of a synchronizer key 21 is larger than a clearance between a sleeve 15 and a reverse output gear side gear spline 10, the first clutch 40 forming a dog clutch is engaged before, and after the engagement of a gear spline 15a and the gear spline 10, the synchronous engagement type second clutch 50 is engaged. Smooth engagement is thereby performed.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a gear type transmission used in automobile transmissions and the like.

(Prior Art) Gear type transmissions used in vertically mounted automobile transmissions generally have a main shaft that serves as an output shaft,
It is comprised of a countershaft parallel to this, a plurality of sets of transmission gears provided on these shafts, and a synchronous mesh clutch device for selectively synchronously meshing these plurality of sets of transmission gears. In this case, power transmitted from the crankshaft or the like of the engine is transmitted to the countershaft via the drive gear, and then transmitted to the main shaft at a predetermined gear ratio via the selected transmission gear. Further, this type of transmission is generally provided with a reverse gear mechanism that includes a pair of reverse gears provided on a main shaft and a countershaft, and an idle gear meshingly connected between these reverse gears. This reverse gear mechanism can be divided into a selective sliding type and a constant mesh type depending on the reverse selection method.

By the way, in the case of a constant-meshing type reverse gear mechanism, conventionally, the reverse gear on either the main shaft side which is the output side or the counter shaft side which is the input side is rotatable relative to the shaft, and the reverse gear on this one side It was common for the reverse gear and shaft to be connected in a detachable manner using a clutch. By providing a clutch on either side in this way, it is possible to selectively operate the reverse mechanism.

However, it has been known that such a structure in which only a clutch is provided on one side is likely to cause so-called rattling noise. In other words, in this type of reverse gear mechanism, the two reverse gears on the main shaft side and the countershaft side are always engaged with the idle gear, so for example, if the clutch is installed on the countershaft side, during normal driving Rotational fluctuations from the axle are transmitted to the reverse gear via the main shaft,
A so-called rattling noise occurs. Conversely, if the clutch is provided on the main shaft side, especially during idling, rotational fluctuations from the engine side will be transmitted to the countershaft side gear, resulting in so-called idle teeth rattling noise.

Therefore, in order to prevent the occurrence of these rattling noises, for example, as described in Japanese Patent Publication No. 60-37338, clutches are provided on both the main shaft side and the countershaft side, and these are simultaneously connected by one soft fork. It has been proposed that the device be operated to engage and disengage.

(Problem to be Solved by the Invention) When a reverse gear mechanism in a gear type transmission is provided with clutches on both the main shaft side and the countershaft side as described in the above publication, the clutches on the main shaft side and the countershaft side Since the reverse gear is always connected via the idle gear, it is difficult to smoothly engage the two clutches. In particular, when at least one of the pair of clutches is a normal dog clutch that does not have a synchronizer and is difficult to engage, it becomes even more difficult to smoothly engage the two clutches.

In the above reverse gear mechanism, if synchronized mesh clutches can be provided on both the main shaft side and the countershaft side, the above-mentioned disadvantages can be overcome. In reality, this is difficult in terms of space and cost.

The present invention has been made in view of the above problems, and is one of the clutches provided for engaging and disengaging the gears on both the input side and output side shafts in a reverse gear mechanism of a gear type transmission. The purpose of this invention is to enable smooth engagement of these two clutches, with one being a dog clutch and the other being a synchronized mesh type clutch.

(Means for Solving the Problems) The present invention provides a method of solving the problems by mutually shifting the engagement timings of two clutches that engage the input side and output side gears that are drivingly connected to each other with respect to the respective shafts. If it is possible to make these two clutches engage smoothly, and if one is a dog clutch and the other is a synchronized mesh clutch, then the inertia of the dog clutch that is difficult to engage due to the fact that the gears are not engaged with their respective shafts It is advantageous to engage the synchronized clutch first when the gear is small, and then engage the synchronous mesh clutch, which is relatively easy to engage, when the gear is engaged with the output or input shaft and the inertia becomes large. The structure is based on the knowledge that two shafts on the input side and the output side are provided with gears that are rotatably connected to each other, and are connected to each other by a pair of clutches. In a gear type transmission equipped with a gear mechanism that can be detachably connected, one clutch is a dog clutch, the other clutch is a synchronized mesh clutch, and the synchronized mesh clutch is engaged after the dog clutch is engaged. The feature is that the engagement timing of both clutches is set to match.

In the above configuration, in order to make both clutches engage smoothly, it is best to set the engagement timing of both clutches so that the synchronous mesh type Kurasochi engages after the side surfaces of the teeth of the dog clutch engage. .

(Operation) When a soft operation is performed, first, the dog clutch is engaged, and a gear is engaged with the shaft on either the input side or the output side. Further, after the dog clutch is engaged, the synchronous mesh clutch is engaged at a predetermined timing, and the other gear is thereby engaged with the shaft. Power is transmitted from the input-side shaft to the output-side shaft through both of these clutches and both gears that are drivingly connected to each other.

In operating the clutch, the dog clutch is engaged relatively easily because it is carried out at a stage when the gears are not engaged with their respective shafts and the inertial force is small.

Also, when the dog clutch engages, the gear engages with the shaft on the output side or the input side, and the inertia force increases.
The other clutch starts to engage in two states, and the clutch that starts to engage in this state is a synchronized mesh clutch that is relatively easy to engage, so smooth engagement is possible.

Further, by making the synchronized mesh clutch engage after the side surfaces of the teeth of the dog clutch engage, the two clutches can engage more smoothly.

(Example) Examples will be described below based on the drawings.

FIG. 1 is a longitudinal cross-sectional view of a reverse gear mechanism portion of a gear type transmission in an automobile transmission according to an embodiment of the present invention, FIG. 2 is a cross-sectional view of FIG. 1, and FIG.
Figure I[l-I[[Cross-sectional view, Figure 4 is IV= of Figure 2]
It is a V sectional view.

In this embodiment, the transmission 1 includes a main shaft 2 serving as an output shaft, and a countershaft 3 that receives power from an input shaft (not shown) disposed coaxially with the main shaft 2. The main shaft 2 and the countershaft 3 are provided with a forward gear mechanism for each stage (FIG. 1 shows a 5-speed driver gear 4 and a 5-speed output gear 5 that constitute a 5-speed gear mechanism). It is provided. In addition, a reverse input gear 6 is provided at the rear end of the countershaft 3.
A reverse output gear 7 is also relatively rotatably provided on the main shaft 2 at a position corresponding to the reverse input gear 6. Further, the idle gear shaft 8, which is arranged parallel to the main shaft 2 and the counter shaft 3 at a predetermined interval, is provided with a reverse idle gear 9 that is constantly engaged with the reverse input gear 6 and the reverse output gear 7. There is. These three constantly meshing gears 6.
7.9 and two clutches 40° and 50, which will be described later, constitute a reverse gear mechanism.

The reverse output gear 7 has an internally toothed gear spline 10 integrally formed at one end in the axial direction, and is relatively rotatably connected to the main shaft 2 via the bearing 11 and the sleeve 12 as described above. Supported.

A sleeve 14 is provided on the main shaft 2 at a position facing the reverse output gear 7 with a spacer 13 in between.
The sleeve 14 is spline-fitted with a sleeve 15 having an externally toothed gear spline 15a that engages with and disengages from the gear spline IO of the reverse output gear 7. This sleeve 15 engages with and disengages from the gear spline lO of the reverse output gear 7 by sliding in the axial direction, and the reverse output gear 7
is connected or unconnected to the main shaft 2.

The gear spline lO of the reverse output gear 7 and the sleeve 15 constitute a first clutch 40. and,
The sliding operation of the sleeve 15 is performed by the shift fork 1, which will be described later, being engaged with a fitting groove 15b formed on the outer periphery of the sleeve 15.
6.

The reverse input gear 6 has a gear spline 17 integrally formed on one end in the axial direction, and is connected to the counter non-nut 3 via the hair ring 18 with the gear spline 17 facing inward. is supported for relative rotation. Further, the above-mentioned 5-speed input gear 4 is supported on the counter nut 3 so as to be relatively rotatable so as to face the reverse input gear 6. The fifth-speed input gear 4 is meshed with a fifth-speed output gear 5 spline-fitted to the main shaft 2.

A clutch hub 19 is spline-fitted onto the countershaft 3 between the fifth speed gear 4 and the reverse input gear 6. A sleeve 20 having a gear spline 20a on the inner periphery is spline-fitted to the outer periphery of the clutch hub 19, and the sleeve 20 and the clutch hub 1
A synchronizer key 21 is locked between the synchronizer key 9 and the synchronizer key 9. Further, on both left and right sides of the clutch hub 19, a synchronizer ring 24 is formed on the end surface of the fifth speed input gear 4, and a synchronizer ring 24 is formed on the end surface of the fifth speed input gear 4, which faces the tapered cone portion 22 formed on the end surface of the gear spline 17 that is integrated with the reverse input gear 6. A synchronizer ring 25 is arranged to face the tapered cone portion 23.

A gear spline 26 is provided at the host portion of the second and fifth speed input key gears 4 so as to face the synchronizer ring 25 .

The clutch hub 19 and sleeve 20, the left and right gear splines 17.26 and the synchronizer ring 2
4.25 and the synchronizer key 21 constitute a second clutch 50 that engages synchronously on the left and right sides. Further, on the lower surface side of the synchronizer key 21, there is a notch 27 for positioning at a position closer to the reverse input gear 6 side than the center.
On the other hand, a pin hole 28 is provided in the clutch hub 19 opposite to this recess 27. A spring key 29 whose head engages with a recess 27 on the side of the synchronizer key 21 to regulate the position of the synchronizer key 21 is set in the pin hole 28 .

The synchronizer key 21 is normally locked by the spring key 29, and in this state there is a large rearance between the synchronizer ring 24 on the reverse input gear 6 side and the synchronizer ring 25 on the 5th speed input gear 4 side. A small clearance is formed between the two. Further, the above-mentioned clearance between the synchronizer key 21 and the synchronizer ring 24 on the reverse input gear 6 side is between the gear spline IO on the reverse output gear 7 side in the first clutch 40 and the gear spline 15λ on the sleeve 15 side that meshes therewith. The clearance is set to be larger than the set clearance by a predetermined amount.

The shift operation of the sleeve 20 of the second clutch 50 is performed by the common shift fork 16 together with the shift operation of the sleeve 15 of the first clutch 40. Therefore, a fitting groove 20b for engaging the shift fork 16 is formed on the outer periphery of the sleeve 20 of the second clutch 50, and the first clutch 40 and the second clutch 50 are located at the same position in the axial direction. It is located in

The shift fork 16 includes first
The sleeve 15 of the first clutch 40 and the sleeve 20 of the second clutch 50 are simultaneously engaged from the sides, and the sleeve 15 of the first clutch 40
The first arm 16a has a circular arc shape along the outer circumference, and the second arm 16b has a circular arc shape along the outer circumference of the sleeve 20 of the second clutch 5o. And this first arm 16
The fitting groove 15b of the sleeve 15 of the first clutch 40 and the second
A fitting portion 31.3233 that engages with the fitting groove 20b of the sleeve 20 of the clutch 5o is provided. This knot fork 16 has a sleeve-shaped support portion 16 located approximately midway between the first clutch 4o and the second clutch 50.
C, and is slidably supported by a guide shaft 35 that is fixedly arranged on the canong 34 side parallel to the main shaft 2 and counter nut 3. Further, in this shift fork 16, a lever portion 16d for a shift operation is provided on the upper surface side of the support portion 16c, and the lever portion 16d is provided at right angles to the guide shaft 35. A rod 36 is provided upright. On the other hand, the f-nymph lever 38, which is arranged to be rotated in conjunction with the operation of the knot knob 37, has a cam groove 39 at its tip that lies down toward the reverse gear device. The tip of 36 is engaged.

The soft fork 16 is operated by the knot knob 37.
It is moved along the guide shaft 35 via the shift lever 38 and rod 36. When the shift fork 16 is moved to the right side (toward the reverse gear device) in FIG. 1, the first clutch 40 is engaged and the second clutch 50 is engaged to the reverse gear device side. As a result, the reverse input gear 6 is locked to the counter shaft 3 via the sleeve 20 and the clutch hub 19, and the reverse output gear 7 is locked to the main shaft 2 via the sleeve 15. ．． Due to the meshing of the reverse idle gear 9 and the reverse output gear 7, power is reversely transmitted from the counter shaft 3 to the main shaft 2. In that case, the second
Since the reverse side clearance of the synchronizer key 21 in the first clutch 50 is set larger than the clearance between the sleeve 15 in the first clutch 40 and the gear spline IO on the reverse output gear 7 side, the engagement of the two clutches 40 and 50 is reduced. In this case, the first clutch 40 constituting a normal dog clutch is engaged first,
Then, in the first clutch 40, after the teeth of the gear spline +5a of the sleeve 15 and the teeth of the reverse output gear 7 side gear spline IO are engaged, the second clutch 50 of the synchronous mesh type is engaged, and both clutches are engaged. 40
．． 50 degrees of smooth engagement is achieved. Here, the above two clearances are set so that the second clutch 50 starts to engage after the side surfaces of the teeth of the gear splines 15a and 10 in the first clutch 40 are securely engaged.

Next, the operation of the above device will be explained with reference to FIGS. 5 to 14. In addition, in FIGS. 5 to 14, (a) shows the operating state of the first clutch 40 based on the gear spline 10.
．． 15a and a longitudinal cross-sectional view of the first clutch 40, and (b) shows the operating state of the second clutch 50 with gear splines 17, 20a, teeth of synchronizer rings 24 and 25, and a synchronizer key. 21 and key grooves 24a and 25a, and a longitudinal sectional view of the clutch 50.

(i) FIG. 5 shows the transmission 1 in a neutral state.

In this state, both the first clutch 40 and the second clutch 50 are disengaged.

(11) FIGS. 6 to 9 are state diagrams showing a gear shift to the reverse side. When the knot knob 37 is moved to the reverse side, the gear splines 10 and 15a of the first clutch 40 first engage with each other, and as shown in FIG. The synchronous operation of the clutch 50 is started.

That is, the synchronizer key 21 that is locked and moved by the sleeve 20 is connected to the synchronizer ring 2 on the reverse side.
The synchronizer ring 24 is brought into contact with the tapered cone portion 22 of the reverse input gear 6 by contacting the end face of the keyway 24a of the reverse input gear 6 and pushing the synchronizer ring 24. In addition, in this state, the synchronizer ring 24 rotates relative to the taper cone portion 22 by the gap needle in the keyway 24a,
The chamfered surface of the gear spline 20a on the inner surface of the sleeve 20 is in a position opposite to the chamfered surface of the reverse side synchronizer ring 24.

Then, when the sleeve 20 tries to move further, as shown in FIG. 7, the gear spline 20a on the sleeve 20 side
The chamfer surface of the synchronizer ring 24 comes into contact with the chamfer surface of the synchronizer ring 24 to prevent movement of the sleeve 20, and the tapered cone portion 22 of the reverse input gear 6 is pushed to generate frictional torque and perform synchronization.

Then, when synchronization is completed, the above friction torque disappears,
The blocking force of the sleeve 20 is also released, and the sleeve 20
moves, the gear spline 202L of the sleeve 20 passes through the teeth of the synchronizer ring 24 as shown in FIG. 8, and engages with the gear spline 17 on the reverse input gear 6 side as shown in FIG. Shift software is completed.

(Mountain) Figures 10 and 11 show the software for returning from the reverse position to the neutral position (without reverse).
FIG. When the sleeve 20 is moved in the direction of return from the reverse state shown in FIG. 9, as the sleeve 20 moves, the synchronizer key 21 moves as shown in FIG.
After the sleeve 20 moves to a position where it is locked by the spring key 29, the sleeve 20 may move further and lock the synchronizer key 21, returning to the state shown in FIG. In some cases, the synchronizer key 21 is locked as shown in FIG. 11, and then the sleeve 20 and synchronizer key 21 are moved together to the position shown in FIG. It doesn't matter which form it takes.

(iv) FIGS. 12 and 13 are operating state diagrams illustrating a shift to the fifth speed side. When the sleeve 20 is moved from the neutral position shown in FIG.
Press 5 and set the synchronizer ring 25 to 5th gear input gear 4.
It is brought into contact with the tapered cone portion 23 at the end. Then, the synchronizer ring 24 rotates relatively by the gap needle of the keyway 25a, and faces either the chamfer surface of the gear spline 20a on the inner surface of the sleeve 20 or the chamfer surface of the fifth speed side non-chronizer ring 25, as shown in FIG. sleeve 20
The chamfer surface of the side gear spline 20a and the chamfer surface of the synchronizer ring 25 come into contact to perform synchronization. When the synchronization is completed, the sleeve 20 moves further and its gear spline 20a engages with the gear spline 26 on the 5th speed input gear 4 side, as shown in FIG. 13, and the shift is completed.

(v) FIG. 14 is an operating state diagram illustrating a shift (without 5th gear) to return from the 5th gear position to the neutral position. When the sleeve 20 is moved in the return direction from the 5th gear position in FIG. Ru. By locking the spring key 29 with the synchronizer key 21 in this manner, erroneous operation toward the reverse side is prevented.

In the above embodiment, the engagement timing of the two clutches is shifted by making a difference between the clearance in the first clutch and the clearance in the second clutch, or the engagement timing of the two clutches is changed. As a means for shifting, it is also possible to provide a plurality of shift forks and to control the two clutches independently.

Further, the present invention is not limited to reverse gear mechanisms in automobile transmissions, but can also be applied to gear mechanisms in gear type transmissions for various other uses.

(Effects of the Invention) Since the present invention is configured as described above, one of the clutches provided for engaging and disengaging the gears from the two shafts on the input side and the output side is a dog clutch, and the other is a synchronous mesh type clutch. When used as a clutch, the dog clutch is engaged when the inertia is small, and then when the inertia is large, the synchronous mesh clutch is engaged, thereby achieving smooth engagement of the two clutches. can.

[Brief explanation of the drawing]

FIG. 1 is a longitudinal cross-sectional view of a reverse gear mechanism portion of a gear type transmission in an automobile transmission according to an embodiment of the present invention, FIG. 2 is a cross-sectional view of FIG. 1, and FIG.
FIG. 4 is a sectional view taken along IV-IV in FIG. 2, and FIGS. 5 to 14 are explanatory views of the operating state of the same embodiment. 1: Transmission, 2. Main shaft (output side), 3: Counter shaft (input side), 6. Reverse input gear, 7
・Reverse output gear, 9. Reverse idle gear! 0
・Gear spline, 15 sleeve, 15a gear spline, 16 soft fork, 17 gear spline, 19 clutch hub, 20 sleeve, 21. Non-chronized key 22, 23 taper cone part, 24.25,
Synchronizer ring, 40. 1st clutch, 50・
Second clutch.

Claims (2)

[Claims] (1) A gear type equipped with a gear mechanism in which gears are provided on two shafts on the input side and output side so that they can rotate freely relative to each other, and are mutually drivingly connected. A pair of clutches connects the gears to each shaft in a freely engaging and disengaging manner. In the transmission, one clutch is a dog clutch, the other clutch is a synchronized mesh clutch, and the engagement timings of both clutches are set so that the synchronized mesh clutch is engaged after the dog clutch is engaged. Gear type transmission. (2) The gear type transmission according to claim 1, wherein the engagement timing of both clutches is set so that the synchronized mesh clutch is engaged after the side surfaces of the teeth of the dog clutch are engaged.