JP3849893B2 - Gear transmission structure - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a gear type transmission structure, and more particularly to a structure of a manually operated gear type transmission.
[0002]
[Prior art]
2. Description of the Related Art Conventionally, for example, as a manually operated gear-type transmission in a vertical engine type vehicle, an input shaft and an output shaft are arranged adjacent to each other on the same axis, and a countershaft is parallel to these shafts. A structure having a plurality of transmission gear pairs arranged and meshing with each other in pairs with the input shaft, the output shaft and the counter shaft is generally well known.
[0003]
In such a gear-type transmission, first, the rotational driving force of the input shaft is decelerated at a constant reduction ratio by a reduction gear and transmitted to the counter shaft, and the rotational driving force transmitted to the counter shaft is shifted at each stage. A type of transmission that transmits to the output shaft side by a pair of transmission gears having different ratios is generally used. This type is called an “input reduction gear type” because deceleration is performed between the input shaft and the counter shaft.
[0004]
However, in the case of this input reduction gear type transmission, the reduction gear is provided fixed to the shaft on both the input shaft side and the counter shaft side, and there are various disadvantages as described below, for example. That is,
(1) In the pair of reduction gears of the counter shaft and the output shaft, first, a large decelerated driving torque is input. For example, the tooth width, the shaft diameter, and the distance between the input shaft and the counter shaft are set large. For example, it is necessary to set the strength and rigidity of each gear and shaft to be high, which makes it difficult to reduce the size and weight of the transmission.
[0005]
(2) When the engine is stopped when the vehicle is stopped, so-called idling, all idle gears are idled as the countershaft rotates. (Sound) increases.
[0006]
(3) Since the counter shaft is decelerated by the reduction gear pair and driven with a large torque, and further, the torque is amplified in accordance with the gear ratio of each transmission gear pair, for example, a gear position including a synchronizer (synchromesh device). The inertia weight acting on the switching mechanism (that is, so-called inertia) increases, and it is difficult to reduce the shift operation force.
[0007]
For such problems, for example, as shown in European Patent Application No. 219240, an "output reduction gear type" that decelerates between a counter shaft and an output shaft is considered. .
[0008]
In the case of this type of gear-type transmission, the rotational torque of the input shaft is transmitted to the counter shaft without being amplified, so that the input load to each transmission gear is reduced. In addition, since there is no fixed reduction gear pair between the input shaft and the counter shaft, there is no influence of the gear ratio of the reduction gear pair on the operation of the synchronization device as in the prior art. The inertia that acts on the
[0009]
In addition, the idle rattling sound can be reduced because the counter shaft does not rotate in the neutral state.
[0010]
[Problems to be solved by the invention]
As described above, by using the output reduction gear type, it is basically possible to cope with problems in the conventional input reduction gear type gear type transmission. In the reduction gear type gear-type transmission, there are various technical problems to be solved or various specific technical matters for which further improvement is desired for practical use.
[0011]
For example, there are various problems that occur as the rotational speed of the countershaft increases. That is, in the case of a conventional input reduction gear type transmission, the countershaft is decelerated according to the gear ratio of the reduction gear pair provided between the input shaft and the reduction ratio is basically set to the gear position. Regardless. That is, in this case, the rotation speed of the counter shaft is lower than the rotation speed of the input shaft regardless of the gear position.
[0012]
However, in the case of the output reduction gear type transmission described above, the countershaft is shifted according to the gear ratio of the gear pair of the selected shift stage, and at higher speeds than a certain level, the speed is increased. The number of rotations is higher than that of the shaft.
[0013]
In other words, in this case, if the gear ratios of the respective transmission gear pairs are the same, the rotational speed of the countershaft becomes considerably higher than that in the case of the input reduction gear type at a certain shift stage or higher.
[0014]
Therefore, how to support the countershaft becomes a problem. In particular, in the reduction gear pair, since the driving torque input from the input shaft is decelerated by the reduction gear of the counter shaft and the reduction gear of the output shaft, a large torque acts and the tooth contact of each gear changes. It has an easy structure. If the positional relationship between the reduction gear pair is slightly changed in the thrust direction or radial direction, abnormal noise such as uneven wear or rattling noise may occur in the reduction gear pair, or the life of the reduction gear pair may be reduced. There is a risk of impact.
[0015]
In such an output reduction gear type transmission, one supporting structure is disclosed in the document Proc lnstn Mech Engrs 1974 vol.188 12/74 (P169-187). This supports a main shaft composed of an input shaft and an output shaft, and a counter shaft at three locations, that is, an input side end, an input side of a reduction gear pair, and an output side.
[0016]
In this configuration, the input side end of the main shaft and the input side of the reduction gear pair are supported by a taper bearing, and the output side of the reduction gear pair is supported by a roller bearing.
[0017]
In this prior art, both sides of the reduction gear are certainly supported, so that the support rigidity can be increased to some extent. However, it is the speed change gear that reliably defines the position in the thrust direction by the taper bearing, and the thrust gear for the reduction gear pair. The definition of the direction position was insufficient.
[0018]
The present invention has been proposed in order to eliminate the drawbacks of the prior art described above. The purpose of the present invention is to determine the position of a reduction gear pair that is susceptible to change in tooth contact by thrust acting in the thrust direction and radial direction. It is an object of the present invention to provide a gear-type transmission structure that can support the shaft reliably and can suppress the occurrence of abnormal noise such as uneven wear and rattling noise of the reduction gear and can improve the service life.
[0019]
[Means for Solving the Problems]
In order to solve the above-described problems and achieve the object, the gear-type transmission structure of the present invention has the following configuration. That is,
An input shaft, a counter shaft disposed in parallel with the input shaft, an output shaft disposed on the same axis as the input shaft, and a pair of the input shaft and the counter shaft are provided to mesh with each other. A plurality of transmission gear pairs, a counter gear pair paired with the counter shaft and the output shaft, which are provided in pairs to decelerate and transmit the rotation of the counter shaft to the output shaft, and the reduction gear In the gear-type transmission structure that transmits the rotation of the input shaft to the output shaft through the counter shaft or directly by selecting one of the pair and the transmission gear pair through a synchronization device, The input shaft and the output shaft are pivotally supported at three places, the power input side end of the input shaft and both sides of the reduction gear of the output shaft, and the counter shaft is supported on the power input side of the counter shaft. The shaft is supported at three locations, one end and the other side of the reduction gear. Is rotatably supported by tapered bearing having a tapered surface inclined to both sides of the reduction gear so as to sandwich the reduction gear pair provided on the output shaft and the counter shaft in the thrust direction, both side portions of the reduction gear of the output shaft The taper bearings provided on the counter shaft are arranged so that the side surfaces in the direction in which the taper surface extends are opposed to the reduction gear, and the taper bearings provided on both sides of the reduction gear of the counter shaft are The side surfaces in the direction in which the surface spreads are arranged so as to face each other with respect to the reduction gear .
[0020]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.
[0021]
<Overall transmission structure>
First, the overall structure of a transmission according to an embodiment of the present invention will be described. FIG. 1 is a side sectional view showing the overall structure of a transmission according to an embodiment of the present invention. FIG. 2 is an upper cross-sectional view showing a mounting position of the reversing mechanism in the transmission case.
[0022]
In FIG. 1, a transmission 1 is a manual transmission type rear wheel drive manual transmission. In a transmission case 2 of the transmission 1, an input shaft 3 and a counter shaft 4 arranged in parallel in the vertical direction are provided in the transmission case. The bearings 50 to 54 are rotatably supported. An output shaft 5 having the same rotation shaft as that of the input shaft 3 is slidably fitted to the rear end of the input shaft 3, that is, the output side, and is supported by bearings 54 and 55. The input shaft 3 is provided with a fifth speed input gear 6, a reverse input gear 7, a first speed input gear 8, a second speed input gear 9, and a third speed input gear 10 in order from the input side. 3 or integrally formed by splines and rotates together with the input shaft 3. On the counter shaft 4, a fifth speed counter gear 12, a reverse counter gear 13, a first speed counter gear 14, a second speed counter gear 15, and a third speed counter gear 16 are provided so as to be rotatable with respect to the counter shaft 4 in order from the input side. A 4-speed counter gear (deceleration input gear) 17 is coupled to the counter shaft 4 by a spline and rotates together with the counter shaft 4. A four-speed drive gear (deceleration output gear) 11 is formed integrally with the output shaft 5 or connected by a spline, and rotates together with the output shaft 5.
[0023]
5-speed input gear 6 and 5-speed counter gear 12, 1-speed input gear 8 and 1-speed counter gear 14, 2-speed input gear 9 and 2-speed counter gear 15, 3-speed input gear 10 and 3-speed counter gear 16, 4-speed The input gear (deceleration output gear) 11 and the 4-speed counter gear (deceleration input gear) 17 are meshed with each other, and the output shaft 5 includes the 4-speed input gear (deceleration output gear) 11 and the 4-speed output gear (deceleration input). The gear rotates together with the counter shaft 4 by meshing with the gear 17.
[0024]
On the other hand, the reverse input gear 7 of the input shaft 3 meshes with a reverse idle gear described later, and the reverse idle gear meshes with the reverse counter gear 13 to reverse the rotation of the input shaft 3 and transmit it to the counter shaft 4.
[0025]
As described above, in the transmission 1, the counter shaft 4 and the output shaft 5 are always meshed with each other by the meshing of the 4-speed input gear (deceleration output gear) 11 and the 4-speed output gear (deceleration input gear) 17. When a certain gear stage is connected, the rotational force is transmitted from the input shaft 3 to the output shaft 5 via the counter shaft 4, that is, the gear is shifted between the input shaft and the counter shaft, and the counter Since deceleration is performed between the shaft and the output shaft, it can be called a so-called output reduction type.
[0026]
A 5-R shift synchronizer 18 is coupled by splines between the 5-speed counter gear 12 and the reverse counter gear 13 on the counter shaft 4 so as to rotate together with the counter shaft 4. Similarly, a 1-2 speed synchronization device 19 is coupled by a spline between the first speed counter gear 14 and the second speed counter gear 16 on the counter shaft 4 so as to rotate together with the counter shaft 4. Further, a 3-4 shift synchronizer 20 is coupled by a spline between the third speed input gear 10 and the fourth speed drive gear (deceleration input gear) 17 on the input shaft 3 so as to rotate together with the input shaft 3. Yes.
[0027]
The 5-R transmission synchronization device 18 and the 1-2 transmission synchronization device 19 are a clutch hub meshing with the countershaft 4 and a sleeve that is coupled to the clutch hub 8 and is slidable in the longitudinal direction of the shaft by a shift fork 33 described later. The sleeve is meshed with one of the gear chamfers of the counter gears disposed on both sides of the synchronizers 18 and 19, respectively, and the rotation of the input shaft 3 is counterclockwise via the counter gear of the shift stage. 4 is transmitted.
[0028]
In particular, the 1-2 shift synchronization device 19 does not require a large operating force when operating the shift lever (that is, has a large synchronization capacity) as compared with the single cone type 5-R transmission synchronization device 18. Device. The double cone type 1-2 shift synchronizer 19 is engaged with the clutch hub 19a meshed with the countershaft 4 and the clutch hub 19a, as shown in FIG. A sleeve 19b slidable in the axial direction by a shift fork shown in the figure, a synchronizer key 19f fitted in a groove between the clutch hub 19a and the sleeve 19b, an outer cone (synchronizer ring) 19c having a conical inner surface, a clutch An inner cone 19d, which is joined to the hub 19a and has an outer surface conically formed at the same angle as the inner surface of the outer cone 19c, is connected to the first speed counter gear 14 via a synchronized gear 19g, and is connected to the inner cone 19d and the outer cone 19c. An intermediate cone (sink) between which the driving force is transmitted from the clutch hub 19a by friction force And a Na customizing cones) 19e, it is possible to increase the synchronizing capacity by increasing the friction coupling surface between the synchronizer ring 19c and the clutch hub 19a as compared with the single cone.
[0029]
In the mission case 2, a control rod 30 to which an operating force from the shift lever 34 is transmitted via a connecting rod 33 and a joint 32 is provided. The connecting rod 33 is connected to the shift lever 34, and is supported in the transmission case so that it can be tilted in the front-rear direction and the left-right direction of the vehicle around the spherical portion 33a by the driver's shift lever operation. Yes. The control rod 30 is slidably supported by the transmission case 2 above the input shaft 3 and is moved to the center of its own axis by the movement of the connecting rod 33 in the left-right direction (the normal direction of the drawing in FIG. 1). It is pivotally supported. A joint arm 31 extending downward is fixed to the control rod 30 at its boss portion 31a. The joint arm 31 is engaged with the reversing mechanism 40 and transmits the operation of the control rod 30 in the front-rear direction and the rotational direction to the reversing mechanism 40. The reversing mechanism 40 includes a reversing member 41 that is rotatably supported by a support shaft 42 installed in the left-right direction in the mission case 2 and is slidably supported along the longitudinal direction of the support shaft 42. . The reversing member 41 is provided with a select arm 43 extending downward on the opposite side across the connecting shaft to the joint arm 31 and the support shaft 42. The support shaft 42 is provided with a recess 42a in the longitudinal direction of the shaft. As shown in FIG. 16, the ball 41a is fitted into the recess 42a by the urging force of the compression coil spring 41b, and the support shaft 42 is moderately slid. Is given.
[0030]
The reversing mechanism 40 is a space in which the 1-2 transmission synchronization device 19 of the input shaft 3 is disposed and is a space above the input shaft 3, that is, the first speed input gear 8 above the input shaft 3. It arrange | positions at the cyclic | annular recessed part 3a between the 2nd-speed input gears 9. FIG. Thereby, the layout in the vertical direction of the transmission is advantageous, and for example, the length in the vertical direction of the transmission can be shortened.
[0031]
In FIG. 2, both ends of the support shaft 42 that pivotally supports the reversing mechanism 40 are attached in the vicinity of the case dividing surface X of the mission case 2 divided into three along the axial direction of the shaft, It is fixed with bolts 45 etc. near the case split surface X. An opening 41 c that engages with the joint arm 31 is formed on the upper surface of the reversing member 41. A compression coil spring 44 is wound around the outer peripheral surface of the support shaft 42 located at both ends in the longitudinal direction of the reversing member 41 so that when the reversing member 41 moves in the left-right direction along the axis, it returns to its original position. Press from one side to hold the reversal member in the neutral position.
[0032]
The reversing mechanism 40 is assembled to the transmission case 2 in a sub-assembly state in which the reversing member 41, the support shaft 42, the compression coil spring 44, and the like are assembled in advance. In this way, the support shaft 42 is provided near the case dividing surface X. Thus, the assembly can be easily performed at a position where the hand of the worker can reach.
[0033]
[Other Embodiments]
Next, the structure of a transmission according to another embodiment will be described.
[0034]
FIG. 3 is a side sectional view showing the overall structure of a transmission according to another embodiment of the present invention.
[0035]
The arrows shown in FIG. 3 indicate the flow of the lubricating oil in the mission case 2, and the broken line L indicates the oil level of the lubricating oil when the vehicle is mounted in the mission case 2.
[0036]
The countershaft 4 is sufficiently immersed in the lubricating oil in the transmission case 2, and the lubricating oil is scraped up by the rotational force of the counter gears 13 to 17 on the countershaft 4, Supplied to the shafts 3 to 5 and the bearings of idle gears rotatably supported on the shafts 3 to 5.
[0037]
For the other components, the same members as those in FIG.
[0038]
Next, with reference to FIG.1 and FIG.3, the feature point of the transmission of this embodiment is demonstrated.
[0039]
As shown in FIGS. 1 and 3, the input shaft 3 and the output shaft 5 arranged on the same axis are arranged at three locations by a ball bearing 50 and tapered roller bearings (conical roller bearings in JIS standards) 54 and 55. It is pivotally supported. The ball bearing 50 is disposed at the input side end of the input shaft 3 close to the fifth speed input gear 6. The tapered roller bearings 54 and 55 are arranged on both sides of the output shaft 5 so as to sandwich the fourth speed drive gear 11. Further, the tapered roller bearings 54 and 55 are arranged such that the side surfaces in the direction in which the tapered surfaces expand are opposed to the 4-speed drive gear 11.
[0040]
The counter shaft 4 is pivotally supported at three locations by a cylindrical roller bearing (cylindrical roller bearing in JIS standard) 51 and tapered roller bearings 52 and 53. The cylindrical roller bearing 51 is disposed at the input side end of the counter shaft 4 close to the fifth speed counter gear 12. The tapered roller bearings 52 and 53 are arranged on both sides of the counter shaft 4 so as to sandwich the 4-speed counter gear 17. Further, the tapered roller bearings 52 and 53 are arranged such that the side surfaces in the direction in which the tapered surfaces expand are opposed to the 4-speed counter gear 17.
[0041]
The tapered roller bearings 54 and 55 are arranged so as to face each other with respect to the 4-speed drive gear 11 so as to reliably position the position of the 4-speed drive gear 11 in the thrust direction and the radial direction. Similarly, the tapered roller bearings 52 and 53 are disposed so as to face each other with respect to the 4-speed counter gear 17, thereby reliably positioning the position of the 4-speed counter gear 17 in the thrust direction and the radial direction. Acts as follows.
[0042]
Therefore, the position of the reduction gear pair (four-speed drive gear 11 and four-speed counter gear 17) that easily changes the tooth contact due to the large torque can be securely supported in the thrust direction and the radial direction. It is possible to improve the service life by suppressing the generation of abnormal noise such as wear and rattling noise.
[0043]
Further, the tapered roller bearings 54 and 55 drive the four-speed drive from the transmission gear side and the output shaft side by rotating the rolling element as indicated by arrows S1 and S2 in FIG. It acts to guide to the gear 11 side.
[0044]
Accordingly, the lubricating oil is sufficiently supplied to the meshing portion of the 4-speed drive gear 11 and the 4-speed counter gear 17, the bearing portion that pivotally supports the input gear 3 and the output gear 5, and the like. Can be prevented.
[0045]
The present invention can be applied to modifications or variations of the above-described embodiment without departing from the spirit of the present invention.
[0046]
【The invention's effect】
As described above, according to the present invention, the tapered bearings provided on both sides of the reduction gear of the output shaft are arranged so that the side surfaces in the direction in which the tapered surface expands face each other with respect to the reduction gear. The position of the reduction gear of the output shaft is surely positioned in the thrust direction and the radial direction, and similarly, tapered bearings provided on both sides of the reduction gear of the counter shaft are arranged in the direction in which the tapered surface widens. Since the side surfaces of the counter shaft are arranged so as to face each other with respect to the reduction gear, the position of the reduction gear of the countershaft is surely positioned in the thrust direction and the radial direction. Therefore, the position of the pair of reduction gears, which can easily change the tooth contact due to the large torque , can be pivotally supported in the thrust direction and radial direction, and the occurrence of abnormal noise such as uneven wear of the reduction gears and rattling noise can be suppressed. Life can be improved.
[0047]
In addition, the taper bearing is arranged so that the end faces in the direction in which the taper surface spreads face each other with respect to the reduction gear pair, so that it is easy to guide the lubricant to the reduction gear side and prevent seizure of the reduction gear pair. it can.
[0048]
[Brief description of the drawings]
FIG. 1 is a side sectional view showing an overall structure of a transmission according to an embodiment of the present invention.
FIG. 2 is an upper cross-sectional view showing a mounting position of a reversing mechanism in a transmission case.
FIG. 3 is a side sectional view showing an overall structure of a transmission according to another embodiment of the present invention.
FIG. 4 is a side cross-sectional view showing a detailed configuration of the first-speed stage side of the 1-2 transmission synchronization device.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Transmission 2 ... Mission case 3 ... Input shaft 4 ... Counter shaft 5 ... Output shaft 6 ... 5-speed input gear 7 ... Reverse input gear 8 ... 1-speed input gear 9 ... 2-speed input gear 10 ... 3-speed input gear 11 ... 4-speed drive gear 12 ... 5-speed counter gear 13 ... reverse counter gear 14 ... 1-speed counter gear 15 ... 2-speed counter gear 16 ... 3-speed counter gear 17 ... 4-speed counter gear 18 ... 5-R transmission synchronizer 19 ... 1 -2 shift synchronizer 20 ... 3-4 shift synchronizer 30 ... control rod 31 ... joint arm 32 ... joint 33 ... connecting rod 34 ... shift lever 40 ... reversing mechanism 50-55 ... bearing

Claims (1)

An input shaft, a counter shaft disposed in parallel with the input shaft, an output shaft disposed on the same axis as the input shaft, and a pair of the input shaft and the counter shaft are provided to mesh with each other. A plurality of transmission gear pairs, a counter gear pair paired with the counter shaft and the output shaft, which are provided in pairs to decelerate and transmit the rotation of the counter shaft to the output shaft, and the reduction gear In the gear-type transmission structure that transmits the rotation of the input shaft via the counter shaft or directly to the output shaft by selecting one of the pair and the transmission gear pair via a synchronization device,
The input shaft and the output shaft are pivotally supported at three positions, that is, a power input side end portion of the input shaft and both sides of the reduction gear of the output shaft, and the counter shaft is supported on the power input side of the counter shaft. Are tapered at three locations, one end of each reduction gear and both sides of the reduction gear , and the both sides of each reduction gear are inclined in the thrust direction so as to sandwich the reduction gear pair provided on the counter shaft and the output shaft. It is supported by a taper bearing with a surface ,
Tapered bearings provided on both sides of the reduction gear of the output shaft are arranged so that side surfaces in the direction in which the taper surface expands face each other with respect to the reduction gear,
A gear-type transmission structure in which taper bearings provided on both sides of a reduction gear of the counter shaft are arranged such that side surfaces in a direction in which the taper surface expands face each other with respect to the reduction gear.

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