Transmission

Abstract

The invention relates to a transmission (10) of a motor vehicle, comprising a drive shaft (12) and axially spaced drive gears (11a, 11b) which are rotatably mounted thereon, and comprising a hub (17) which lies between the drive gears and is disposed for conjoint rotation with the drive shaft (12) and by which a selector sleeve (14) can be supported, for conjoint rotation, by means of teeth, the selector sleeve in turn being axially slidable by means of a selector fork (16) and at least one sliding block (18) and being able to be used to connect the drive shaft (12) to the particular drive gear (11a, 11b), and the selector sleeve (14) being divided axially in half.

Description

[0001] Gearbox

[0002] The invention relates to a transmission according to the preamble of patent claim 1.

[0003] DE 102015 100 906 A1 discloses a synchronizing device comprising an input part that can be driven to rotate about a rotational axis, an output part that is arranged coaxially to the input part and is rotatable relative thereto, and a synchronizing ring that is connected to the input part in a rotationally fixed and axially movable manner. The synchronizing ring can be brought into frictional contact at least indirectly with the output part in order to align a rotational speed of the input part and a rotational speed of the output part. Furthermore, the synchronizing device comprises a spring element that is arranged between the input part and the synchronizing ring with preload such that the spring element axially loads the synchronizing ring toward the input part. The spring element has a fastening portion that is fastened axially and radially to the input part.

[0004] The object of the invention is to further develop a transmission in such a way that the quality of the components is higher and the cost factor is taken into account.

[0005] This invention is achieved by means of a transmission having the features of patent claim 1. Further advantageous embodiments of the invention are the subject of the dependent claims.

[0006] One aspect of the invention relates to a transmission of a motor vehicle having a drive shaft with axially spaced drive gears rotatably mounted thereon. Between these gears is a hub that is non-rotatably mounted on the drive shaft. This hub carries a shift sleeve that is non-rotatably connected to the hub by a gearing. The shift sleeve can be axially displaced by means of a shift fork and at least one sliding block to connect the drive shaft to the respective gear.

[0007] Manufacturing a wide internal gear sleeve with a reverse gear geometry is difficult and results in lower quality. Starting with the internal gear, a broaching process is required, and skipping steps, where the steps are more closely aligned and the tools are more cost-effective, is not possible. Reversing both sides cannot be performed in a single step due to the rigidity of the wide tool. This requires rotating the part between reversing a first side and a second side. The wide geometry results in significant deformation due to hardening.

[0008] Typically, shift sleeves are designed to be as narrow as possible. The space between the parts to be moved is usually limited. If this is not the case, the shift sleeve can be doubled, allowing both halves to move independently. In this case, however, a mechanism must be provided to prevent both halves from engaging simultaneously.

[0009] To solve this problem, the shift sleeve is split axially into two halves, a first part and a second part. The design of a split shift sleeve, in which both halves are identical, requires no fixation. The device consists of two sliding blocks, which are required anyway, with a new geometry. This leads to higher part quality and a more cost-effective design.

[0010] In an advantageous embodiment of the invention, the teeth of each half are manufactured separately. This enables, for example, more precise manufacturing and quality of the teeth in each half of the shift sleeve, which leads to overall improved performance and durability of the transmission.

[0011] In another advantageous embodiment of the invention, gear skiving is provided for the gear teeth. Gear skiving is an efficient process for producing precise gear teeth. This leads, for example, to a lower wear rate and a longer service life of the shift sleeve. In another advantageous embodiment of the invention, the shift fork guides both halves together. This facilitates the operation and control of the transmission, since both halves of the shift sleeve can be moved synchronously and smoothly, which also improves gear shifting, for example.

[0012] In another advantageous embodiment of the invention, it is provided that the shift sleeve has a circumferential collar on its outer side, which in particular increases the stability and strength of the shift sleeve and contributes to the overall robustness of the transmission.

[0013] Finally, a further advantageous embodiment of the invention provides for at least one sliding block to engage around the collar. This provides a secure and reliable connection between the sliding block and the shift sleeve, for example, to improve shifting and minimize wear during transmission operation.

[0014] Further advantages, features, and details of the invention will become apparent from the following description of preferred embodiments and from the drawings. The features and combinations of features mentioned above in the description, as well as the features and combinations of features mentioned below in the description of the figures and / or shown alone in the figures, can be used not only in the respective specified combinations, but also in other combinations or on their own, without departing from the scope of the invention.

[0015] The only Fig. 1 shows a cross-section of an area of ​​the gearbox to objectify an arranged shift sleeve.

[0016] Figure 1 shows a schematic cross-section of a possible embodiment of a transmission 10 of a motor vehicle, depicting a first gear 11a and a second gear 11b, as well as a drive shaft 12, wherein axially spaced drive gears rotatably mounted on the drive shaft 12 are provided as the gears 11a, 11b. Furthermore, a hub 13 is provided, which lies between the gears 11a, 11b and is arranged in a rotationally fixed manner with the drive shaft 12. The hub 13 has a shift sleeve 14 which is supported in a rotationally fixed manner by the hub 13 by means of a toothing. The shift sleeve 14 comprises two halves, namely a first part 14a and a second part 14b, and is therefore constructed in two parts. The shift sleeve 14 is axially displaceable by means of a shift fork 16 and at least one sliding block 18 and the drive shaft 12 is connected to the respective gear wheel 11a, 11b.In particular, it is provided here that the shift sleeve 14 is split axially in half, ie that the first part 14a and the second part 14b are provided, or the two parts 14a, 14b are provided as separate parts.

[0017] Also shown is a shift fork mouth 17 and the sliding block 18, which are provided as part of the transmission 10 in Figure 1. The toothing of the respective halves or the respective parts 14a, 14b can be manufactured separately. For the toothing, for example, gear skiving is provided, although other manufacturing processes are also possible. In addition, it is also provided or possible for the shift fork 16 to guide both halves of the shift sleeve 14 and thus the first part 14a and the second part 14b together. Furthermore, it may be possible for the shift sleeve 14 to have a circumferential collar on its outer side. Finally, it is also provided that the at least one sliding block 18 engages around the collar.

[0018] In particular, it is provided that the sliding sleeve or shift sleeve 14 is separated into two identical parts, namely the first part 14a and the second part 14b, thereby eliminating a sliding block groove in favor of the circumferential collars. Furthermore, the sliding block 18 encloses the new sliding sleeve or shift sleeve 14, and the shift cable mouth 17 is correspondingly further developed to provide space for the new sliding blocks 18.

[0019] In other words, the sliding block 18 simultaneously carries the two sleeve halves or parts 14a, 14b. Therefore, these do not need to be connected to each other. Furthermore, a translation T or a translatory movement of the shift fork 17 or sliding block 18 or sliding sleeves or shift sleeves 14 is provided.

[0020] Finally, a first torque M1 and a second torque M2 are provided, which originate from the drive shaft 12 and emanate from the sleeve halves or parts 14a, 14b, respectively, and transfer directly to the respective gears 11a, 11b. Only one sleeve half or part 14a, 14b is ever subjected to a respective torque M1, M2. Shifting the shift sleeve 14 in one direction prevents the simultaneous shifting of two gears by spatially separating them. In other words: the sliding block 18 controls both sleeve halves or parts 14a, 14b simultaneously, without them having to be connected to one another.

[0021] In summary, the invention describes a design for the manufacture of a wide sliding sleeve or shift sleeve 14 or (English) “a design for manufacturing of wide sliding sleeve”.

[0022] List of reference symbols

[0023] 10 gearboxes

[0024] 11a first gear

[0025] 11b second gear

[0026] 12 Drive shaft

[0027] 14 Shift sleeve

[0028] 14a first part

[0029] 14b second part

[0030] 16 shift fork

[0031] 17 Shift fork mouth

[0032] 18 sliding block

[0033] M1 first torque

[0034] M2 second torque

[0035] T Translation

Claims

Patent claims 1. Transmission (10) of a motor vehicle, with a drive shaft (12) and axially spaced drive gears (11a, 11b) rotatably mounted thereon, and with a hub (17) arranged therebetween in a rotationally fixed manner with the drive shaft (12), by means of which a shift sleeve (14) can be carried in a rotationally fixed manner by means of a toothing, which in turn can be axially displaced by means of a shift fork (16) and at least one sliding block (18) and by means of which the drive shaft (12) can be connected to the respective drive gear (11a, 11b), characterized in that the shift sleeve (14) is split axially in half.

2. Gearbox (10) according to claim 1, characterized in that a toothing of the respective halves of the shift sleeve (14) is manufactured separately.

3. Gear (10) according to claim 2, characterized in that a skiving process is provided for the toothing.

4. Transmission (10) according to one of the preceding claims, characterized in that both halves of the shift sleeve (14) can be guided together by means of the shift fork (16).

5. Gearbox (10) according to one of the preceding claims, characterized in that the shift sleeve (14) has a circumferential collar on its outer side.

6. Gear (10) according to claim 5, characterized in that the at least one sliding block (18) engages around the collar.

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