JP4778224B2 - Sub-transmission synchronizer - Google Patents

Description

  The present invention relates to a synchronizer for an auxiliary transmission.

As an example of a synchronizer used for a sub-transmission of a conventional transmission with a sub-transmission, there is a so-called triple cone type synchronizer (see Patent Document 1). This synchronizer is configured such that an outer ring and an inner ring are disposed between a synchronizer hub and a gear which are assembled to each other on a shaft so as to be rotatable relative to each other, and these rings are connected to the synchronizer hub so as to be integrally rotatable. A double cone is arranged between the rings and connected to the gear so as to be integrally rotatable, and three tapered cone clutches are formed between the three rings and the gear.
JP-A-7-63251

  However, in this conventional sub-transmission synchronizer, the load generated by the detent mechanism provided in the synchronizer has a configuration in which the acting force is always constant during the synchronizing process. Is not required, for example, even when the synchro ring is pulled away from the synchronized gear, the detent force acts, and there is a problem that gear shift is difficult to enter particularly at low temperatures.

  SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a sub-transmission synchronizer that optimizes the action of detent force and improves gear shift entry at low temperatures.

  According to a first aspect of the present invention, there is provided a synchronizer hub that is fixedly assembled on a rotating shaft, a synchronized gear that is assembled so as to be freely rotatable with respect to the rotating shaft, a sleeve that is splined to the synchronizer hub, the sleeve, and the sleeve A synchronizer ring disposed between the synchronized gears, and a detent that is splined to the sleeve and moves in the rotational axis direction, and an axial end thereof frictionally engages with the synchronizer ring. Consists of two teeth arranged parallel to the axial direction and a bottom portion connecting the two teeth, and is urged outward by an elastic member installed on the synchronizer hub and pressed against the spline of the sleeve. In the sub-transmission synchronizing device, the teeth constituting the spline of the sleeve have a high height in the axial direction. Teeth and consists lower second tooth, said detent comprises a protrusion protruding outwardly at the bottom between the two teeth.

In the first invention, when the second tooth of the sleeve faces the convex portion of the detent, the tooth of the detent is pressed against the tooth of the sleeve, and the first tooth of the sleeve and the detent of the detent When the convex portion is in contact, the detent tooth is released from being pressed against the sleeve tooth, and the detent force is greater than when the second tooth of the sleeve faces the convex portion of the detent. The teeth of the sleeve and the convex part of the detent are formed to be smaller .

The second invention is, in the first invention, the splines of the sleeve be in engagement with the splines of the synchronized gear, and the convex portion of the first tooth of the sleeve detent contacts.

According to a third invention, in the first invention or the second invention, the convex part of the detent is slidably installed in a hole penetrating in the radial direction formed in the bottom part of the detent. It is formed with a hat-shaped plunger whose sliding amount is regulated.

In a fourth aspect based on the first aspect or the second aspect, the convex portion of the detent is formed integrally with the bottom portion.

  Therefore, in the present invention, the detent force can be changed according to the positional relationship between the convex portion of the detent and the two teeth having different heights of the sleeve, and the spline of the sleeve and the spline of the gear to be synchronized are synchronized. Can be engaged, the detent force can be reduced to improve the gear shift.

In the fourth invention , since the convex part of the detent is formed integrally with the bottom part, the structure can be simplified.

  FIG. 1 shows a transmission 100 to which the present invention is applied. The transmission 100 includes a main transmission gear train 100A as a main transmission and a splitter gear train 100B and a range gear train 100C as auxiliary transmissions. The gear train is selected so as to be a combination of gear trains to be the target shift speed.

  In the transmission according to the present embodiment, the main transmission gear train 100A and the range gear train 100C constitute six gears, and each of these gears is shifted half a gear by the splitter gear train 100B, so that there are 12 forward gears and 2 reverse gears. Are configured.

  FIG. 2 is a diagram illustrating a detailed shape of the synchronization device 10 installed in the splitter gear train 100B and the range gear train 100C.

  The synchronizer 10 will be described. A synchronizer hub 11 that is spline-coupled on a shaft (not shown) and integrally rotates, and is rotatably mounted on the shaft via a bearing so as to be rotatable relative to the synchronizer hub 11. A synchronized gear 12 on the synchronized side, a sleeve 13 splined to the synchronizer hub 11 so as to be movable in the axial direction, and a synchronizer ring disposed between the synchronizer hub 11 and the synchronized gear 12 to form a tapered cone clutch. The outer ring 14, the double cone 15 and the inner ring 16 are used.

  A detent 17 is installed between the synchronizer hub 11 and the sleeve 13. When the sleeve 11 is moved in the axial direction by a shift fork (not shown), the detent 17 presses the end surface of the outer ring 14, and the tapered cone surface 14 a of the outer ring 14. Is frictionally engaged with the tapered cone 15 a of the double cone 15.

  As described above, the outer ring 14 has the tapered cone surface 14a on the inner periphery, frictionally engages with the tapered cone surface 15a formed on the outer peripheral surface of the double cone 15, and has the convex portion 14b formed on the outer periphery. The sleeve 13 is engageable with the inner periphery of the sleeve 13 that is movable in the axial direction. A convex portion 15c that protrudes in the axial direction is formed at the end of the double cone 15 on the side of the synchronized gear 12, and is disposed in an engagement hole 12a formed in the synchronized gear 12. 12 and rotate integrally. Further, a tapered cone surface 15 b is formed on the inner periphery of the double cone 15, and frictionally engages with the tapered cone surface 16 a formed on the outer periphery of the inner ring 16. A tapered cone surface 16 b is also formed on the inner peripheral surface of the inner ring 16, and this tapered cone surface 16 b frictionally engages with the tapered cone surface 12 b formed on the synchronized gear 12.

  The outer ring 14 and the inner ring 16 can be displaced in the axial direction with each other, and are configured to rotate integrally. Specifically, an end portion of the outer ring 14 on the side of the synchronizer hub 11 is formed with an annular portion 14c extending to the center of the shaft, and this annular portion 14c extends until it has a diameter substantially equal to the inner ring 16. Put out. A through hole is formed in the axial direction at a predetermined location overlapping the inner ring 16 of the annular portion 14c in the axial direction. And the convex part 16d extended from the one end 16c of the inner ring 16 fits in this hole so that the movement to an axial direction is possible. The convex portion 12c of the synchronized gear 12 that forms the tapered cone surface 12b extends to substantially the same position as the one end 16c of the inner ring portion 16 in the axial direction.

  With this configuration, an axial force that presses the outer ring 14 toward the synchronized gear 12 is generated, whereby frictional engagement occurs between the tapered cone surfaces, and the rotation of the synchronizer hub 11 is transmitted through each ring. It is transmitted to the synchronized gear 12.

  Further, the shape of the detent 17 and the sleeve 13 that engages with the detent 17 will be described with reference to FIGS. 2 to 7.

  A spline 13 a is formed on the inner peripheral surface of the ring-shaped sleeve 13 so as to be axially displaceable with respect to the detent 17 in the same manner as a conventional sleeve. Here, the spline 13a formed on the sleeve 13 has two kinds of teeth whose heights are different in the axial direction in one tooth, a high tooth 13b (first tooth), and a low height. It is composed of teeth 13c (second teeth), and this switching position X1 (from teeth 13b to teeth 13c) and X2 (from teeth 13c to teeth 13b) are set according to the relationship with detent 17 described later.

  As shown in FIG. 4, the detent 17 includes a spline made up of two teeth 17a and 17b parallel to the axial direction that are in contact with the spline 13a formed on the inner peripheral surface of the sleeve, and a bottom 17c that integrally connects the two teeth. Consists of A hole 17d penetrating in the radial direction is formed at a substantially central portion in the axial direction of the bottom portion 17c, and a hat-shaped plunger 18 is installed in the hole 17d. The shape of the plunger 18 is set so as to protrude to the outer diameter side from the surface 17e on the side facing the spline 13a of the bottom portion 17c. Further, when the flange portion 18 a of the plunger 18 is hooked on the bottom surface 17 d of the detent 17, the amount of movement of the plunger 18 in the outer diameter direction is restricted. Accordingly, a convex portion is formed on the surface 17e of the bottom portion 17c. The plunger 18 is urged outward by a spring 19 installed in a hole 11 a formed in the synchronizer hub 11. Accordingly, the two teeth 17a and 17b of the detent 17 are pressed against the spline 13a of the sleeve 13 by the spring 18, and in addition, the two teeth of the detent 17 are pressed against the spline 13a by the centrifugal force generated by the rotation of the synchronizer hub 11. It is connected firmly by the wedge effect.

  Note that when the two teeth 17a and 17b of the detent 17 are pressed against the spline of the sleeve 13, the plunger 18 faces the second tooth 13c on the lower side of the spline 13 as a whole, but the plunger 18 is configured not to contact the second teeth 13 c of the sleeve 13.

  Next, the relationship between the detent 17 of the teeth 13b and 13c formed on the inner peripheral surface of the sleeve 13 and the plunger will be described.

  As described above, when there is a positional relationship between the sleeve 13 and the detent 17 at a position where the second teeth 13c having a low height and the plunger 18 face, as shown in FIG. 4, the second teeth 13c and the plunger 18, the biasing force of the spring 19 acts on the first tooth 13 b from the plunger 18 through the detent 17. That is, when the synchronizer hub 11 rotates in this state, the detent 17 is pressed against the first teeth 13 b of the sleeve 13 by the urging force of the spring 19 and the centrifugal force due to the rotation. The state in which the wedge effect due to the urging force and the centrifugal force acts results in the largest detent force.

  On the other hand, when the sleeve 13 is moved by the operation of the shift fork and the plunger 18 comes into contact with the higher first tooth 13b of the sleeve, as shown in FIG. Of the teeth 13b. Due to the difference in height between the first tooth 13b and the second tooth 13c, the plunger 18 is pushed back toward the center of rotation against the urging force of the spring 18, and the contact between the detent 17 and the spline 13a is made. Canceled. Therefore, the detent force is only the urging force of the spring 19 and is smaller than when the plunger 18 faces the second tooth 13c.

  Thus, the detent force can be changed by the relationship between the plunger 18 of the detent 17 and the spline 13a of the sleeve 13. Next, the relationship between the changing detent force and the synchronization mechanism will be described.

  In the synchronization mechanism, the detent force is required until the spline 13a of the sleeve 13 comes into contact with the spline 12d of the synchronized gear 12. When the spline 13a meshes with the spline 12d of the synchronized gear 12, the detent force is smaller. Is appropriate. Accordingly, the switching positions X1 and X2 of the two kinds of first teeth 13b and second teeth 13c having different heights are set when the spline 13a of the sleeve 13 contacts the spline 12d of the synchronized gear 12. .

FIG. 6 is a block diagram showing the periphery of the synchronizer ring of the second embodiment, and FIG. 7 is a block diagram showing the shape of the detent 20 in the same manner.

  The detent 20 of this embodiment is different from the detent 17 of the first embodiment in that the convex portion is formed using the plunger 18 whereas the convex portion 21 is integrally formed. Since the convex portion 21 is formed integrally with the detent 20, the configuration of the detent can be simplified with respect to the first embodiment.

Therefore, in the synchronization mechanism provided in the sub-transmission according to the present invention, the spline formed on the sleeve that contacts the detent urged by the spring 19 is composed of two types of teeth 13b and 13c having at least different heights in the axial direction. On the other hand, the detent 20 is composed of two teeth 17a and 17b constituting the detent and a bottom portion 17c connecting the two teeth. The detent 20 has an outer surface on the side facing the spline 13a. When the protruding portion 21 (= plunger 18) protruding in the radial direction is provided, and the protruding portion 21 contacts the teeth 13b having a high height of the spline 13a, the splines 13a of the sleeve 13 and the teeth 17a and 17b of the detent 20 Does not contact and the convex portion 21 faces the lower teeth 13c of the spline 13a, the spline of the sleeve 13 13a and the teeth 17a and 17b of the detent 17 come into contact with each other.

  In this way, by limiting the contact between the spline 13a of the sleeve 13 and the teeth 17a and 17b of the detent 17, the detent force is limited, and a process that does not require the detent force during the synchronization process, for example, the spline 13a of the sleeve 13 In the process after the contact with the synchronized gear 12, the detent force can be suppressed, and the operability of shifting can be improved particularly at a low temperature.

  In the present embodiment, the present invention has been described using the configuration of the triple cone type synchronizer. However, the present invention is not limited to this, and the technical idea of the present invention can be easily applied to a so-called double cone type synchronizer or single cone type synchronizer. Needless to say, it can be applied.

  This is useful for improving the shift operability by limiting the detent force in the synchronization mechanism of the sub-transmission of the transmission.

1 is an overall configuration diagram of a transmission. It is a detailed block diagram around the synchronizer ring of the synchronization device. It is a detailed block diagram around a synchronizer ring. It is a figure which shows the relationship between a sleeve and a detent. It is a figure which shows the relationship between a sleeve and a detent. It is a detailed block diagram around the synchronizer ring of the second embodiment. It is a bird's-eye view of a detent.

Explanation of symbols

10 synchronizer 11 synchronizer hub 12 gear 13 sleeve 13a spline 13b high tooth 13c low tooth 14 outer ring 15 double cone 16 inner ring 17 detent 17a tooth 17b tooth 17c bottom 17d hole 18 plunger 18a collar 19 spring 20 detent 21 convex part

Claims (4)

A synchronizer hub that is fixedly mounted on the rotary shaft;
A synchronized gear assembled so as to be free to rotate with respect to the rotating shaft;
A sleeve that is splined to the synchronizer hub;
A synchronizer ring disposed between the sleeve and the synchronized gear;
A detent that is splined to the sleeve and moves in the direction of the rotational axis, the axial end of which is in frictional engagement with the synchronizer ring;
The detent is composed of two teeth arranged parallel to the axial direction and a bottom portion connecting the two teeth, and is urged outward by an elastic member installed on the synchronizer hub. In the sub-transmission synchronization device pressed by
The teeth constituting the spline of the sleeve are composed of first teeth that are high in the axial direction and second teeth that are low in the axial direction,
The detent includes a convex portion protruding outward at a bottom portion between the two teeth,
When the second tooth of the sleeve and the convex part of the detent face each other, the tooth of the detent is pressed against the tooth of the sleeve, and the first tooth of the sleeve and the convex part of the detent contact each other. The sleeve of the detent is released from being pressed against the teeth of the sleeve so that the detent force is smaller than when the second tooth of the sleeve and the convex portion of the detent face each other. The sub-transmission synchronizer is characterized in that the teeth and the detent convex portions are formed. 2. The auxiliary transmission according to claim 1, wherein when the spline of the sleeve and the spline of the synchronized gear are engaged with each other , the first tooth of the sleeve is in contact with the convex portion of the detent. Machine synchronizer.   The convex part of the detent is formed by a hat-like plunger that is slidably installed in a radially penetrating hole formed in the bottom part of the detent and whose sliding amount is regulated by the flange part. The synchronizer for an auxiliary transmission according to claim 1 or 2.   The sub-transmission synchronizer according to claim 1, wherein the convex portion of the detent is formed integrally with the bottom portion.

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