Device for converting a rotational motion for an electronic transmission actuator
Patent Information
- Application Number
- EP2024707764
- Authority / Receiving Office
- EP · EP
- Patent Type
- Applications
- Current Assignee / Owner
- Priority Date
- 2023-04-20
- Filing Date
- 2024-02-27
- Publication Date
- 2026-02-25
AI Technical Summary
Commercial vehicles require a solution for converting rotary motion into linear motion for electronic transmission actuators, which is not adequately addressed by existing technologies, especially considering the need for shifting multiple gears with a single actuator.
A device using a shift drum arrangement with multiple links and shift forks to convert rotary motion into linear motion, where each link has a neutral position and switching range, allowing for multiple gear shifts through rotational movement, and optionally featuring a modular design with multiple shift drums and pivotable shift forks.
Enables efficient shifting of multiple gears in commercial vehicles by converting rotary motion into linear motion, accommodating long stroke distances and various gear positions, thus addressing the need for electronic transmission actuators in the electrification of commercial vehicles.
Smart Images
Figure EP2024054905_24102024_PF_FP_ABST
Abstract
Description
[0001] DESCRIPTION
[0002] Device for converting a rotary motion for an electronic gear shifter
[0003] The present invention relates to a device for converting a rotary movement into a linear movement for an electronic transmission actuator, and in particular to a shift drum principle for converting a rotary movement into a linear movement in a transmission actuator of commercial vehicles.
[0004] In commercial vehicles, and especially in trucks, pneumatic actuators are often used for transmission actuator units. These actuators use compressed air and a piston to provide the corresponding linear movements for shifting gears. As the commercial vehicle sector progresses toward electrification, transmission actuators are also expected to be electronically operated to shift the various gears of the commercial vehicle. Furthermore, in commercial vehicles, it is often necessary to shift significantly more gears than is necessary for passenger cars. At the same time, all gears, if possible, should be shifted via a single electronic transmission actuator. Currently, these problems are still inadequately addressed.
[0005] Therefore, there is a need for devices to provide linear movements for electronic transmission actuator units of commercial vehicles.
[0006] At least some of the above-mentioned problems are solved by a device for converting a rotary movement into a linear movement according to claim 1. The dependent claims relate to further advantageous embodiments of the device according to claim 1.
[0007] The present invention relates to a device for converting rotary motion into linear motion for an electronic transmission actuator unit of a commercial vehicle. The device comprises:
[0008] - a shift drum assembly for performing the rotary movement; - at least two gates on a surface of the shift drum assembly, each gate having at least one neutral position; and
[0009] - at least two shift forks for carrying out the linear movement, wherein the at least two shift forks each engage in one of the gates in order to convert the rotary movement of the shift drum arrangement into the linear movement.
[0010] Optionally, the shift drum assembly comprises the following: a shift drum with at least two gates or two rotationally coupled shift drums, each with at least one gate. In particular, however, the device also needs to comprise only one shift drum with two, three, four, or even more gates. The shift drums can be arranged on shift rods, and the coupling can either firmly connect the shift rods to one another (e.g., via a screw connection on a flange) or comprise a plug-in connection (e.g., via a polygon or a screw-carrying profile such as a square, hexagon, or hexagonal or similar).
[0011] The at least two gates can comprise a first gate with a first switching range and a second gate with a second switching range. The switching ranges are angular ranges of the rotary movement that lead to a linear movement for the respective shift fork. In contrast, a rotary movement when the gate is in a neutral position does not lead to a linear movement of the shift cables. The neutral position also refers to a predetermined angular range. Optionally, the first gate comprises a first switching range in a first angular range of the shift drum arrangement, where the second gate has a neutral position. Similarly, the second gate can have a second switching range in a second angular range of the shift drum arrangement, where the first gate has a neutral position.
[0012] Optionally, the device comprises a shift rod that is rotationally fixedly coupled to the shift drum assembly for transmitting the rotary movement. At least one of the at least two shift forks can then have a cylindrical portion with a radially inwardly extending projection (e.g., a pin or a stud), wherein the shift drum assembly can be at least partially inserted into the cylindrical portion, so that the cylindrical portion extends positively around the shift drum assembly, while the projection engages with one of the guides.
[0013] Optionally, at least one shift fork of the at least two shift forks comprises a projection (e.g. a pin or a pin) which engages in one of the gates without a portion of the at least one shift fork extending in a form-fitting manner around the shift drum arrangement.
[0014] Optionally, at least one of the at least two shift forks is a pivoting shift fork.
[0015] The device and the shift fork arrangement should in particular be designed to be used in commercial vehicles (i.e. not just be suitable), wherein the shift forks have to cover very long distances due to the forces to be transmitted. Therefore, a stroke that is to be achieved when shifting a gear is at least 10 mm or even greater (e.g. more than 15 mm). This can be achieved, for example, by the shift drum having an appropriate size both in the axial direction and in the radial direction. The axial extension ensures in particular that the achievable stroke is possible across the shift drum, while a large radial direction enables the circumferential length along the shift drum to be correspondingly large, allowing many different shift positions and neutral positions to alternate with one another. In this way, a large number of gears or reduction ratios (e.g. more than 2 gears) can be shifted reliably.
[0016] Further embodiments also relate to an electronic transmission actuator for a commercial vehicle with an electric motor-driven transmission actuator. The transmission actuator comprises a device as described above, wherein a transmission actuator (e.g., an electric motor) is coupled to the device to provide the rotary movement. Further embodiments also relate to a commercial vehicle, in particular a truck, with the above-described electronic transmission actuator.
[0017] Embodiments solve the problems mentioned above by using a shift drum arrangement with multiple gates to convert rotary movements, such as those provided by an electric motor as an actuator, into linear movements of multiple shift forks. In particular, embodiments utilize shift drums where each gate has at least one neutral position within a specific angular range, so that no linear displacement occurs within this angular range. In this way, all gears can be shifted by the multiple gates with one rotation (of up to 360°).
[0018] For example, the gates can be arranged such that a neutral position in one gate corresponds to a shift range in an adjacent gate for that rotation angle range. In this way, a rotation can initially cause displacements of the first shift fork while the second shift fork remains stationary. Subsequently, displacements of the second shift fork can be caused while the first shift fork remains in its neutral position.
[0019] Alternatively or additionally, according to exemplary embodiments, several shift drums can be arranged one behind the other along a shift rod, which are, for example, non-rotatably coupled to one another. Each of these shift drums can then, in turn, have one or more gates, so that the various gears of the transmission can be shifted via at least two shift forks.
[0020] The embodiments of the present invention will be better understood from the following detailed description and the accompanying drawings of the various embodiments, which, however, should not be construed as limiting the disclosure to the specific embodiments, but are merely for explanation and understanding. Fig. 1 shows a device for converting rotary motions into linear motions, such as can be coupled to gear actuators according to one embodiment of the present invention.
[0021] Fig. 2 shows a cross-sectional view through a switching drum of a device for converting rotary into linear movements according to a further embodiment.
[0022] Fig. 3 shows a device for converting rotary movements into linear movements according to a further embodiment.
[0023] Fig. 1 shows a device for converting rotary movements into linear movements, as can be coupled to a transmission actuator of a commercial vehicle (e.g., a truck) according to an embodiment of the present invention. The device comprises a shift drum 110 (or, in general, a shift drum arrangement) for performing the rotary movement D, wherein the shift drum 110 has two guides 111, 112 on a surface of the shift drum 110. A first rotational position P1 of the shift drum 110 is shown at the top, while the same shift drum 10 is shown below, but for a second rotational position P2 (for example, rotated by 180° in the direction of rotation D compared to the shift drum 110 shown above).
[0024] The shift drum 110 is held on both sides by a shift rod 140, which transmits the rotational movement D to the shift drum 110. The device further comprises a first shift fork 131 and a second shift fork 132, wherein the first shift fork 131 engages with a first guide 111 and the second shift fork 132 engages with a second guide 112. Through the engagement, the rotational movement D of the shift drum 110 is converted into linear movements A of the shift forks 131, 132.
[0025] The gates 111, 112 comprise shifting ranges 114 and neutral ranges 115. The shifting ranges 114 are characterized in that, upon rotation of the shift rod 140, an axial displacement of the shift fork 131, 132 occurs, since the gate 111, 112 moves axially in the shifting ranges 114 along the circumferential direction of the shift drum 110. The gate can rise in a straight line or be curved. In this way, an adapted linear movement for the respective shift fork 131, 132 can be effected in response to a rotational movement D of the shift rod 140. The neutral position 115 can be defined by a gate section in which rotations D in an angular range (even if only small) do not lead to any linear movement of the corresponding shift fork 131, 132. According to embodiments, each gate 111, 112 comprises at least one neutral position 115, wherein the shortened neutral positions 115a, 115b are optional.
[0026] In the shift drum 110 shown, the right-hand gate 112 has a neutral range 115 for the first rotational position P1, where the left-hand gate 111 has two shift ranges 114 separated from each other by a shortened neutral range 115a. In the second rotational position P2, the gate 111 has a neutral position 115 on the left side, where the gate 112 has two shift ranges 114 on the right side 115b for this angular position, which are again optionally separated by a shortened neutral position 115b.
[0027] The neutral positions 115 can also be positioned further to the right or left, resulting in continuous gates 111, 112 as they rotate around the shift drum 110. The shortened neutral positions 115a, 115b serve to better separate the two adjacent shift states 114. The shift states 114 represent, for example, a transition between different gears, e.g., from a first gear to a second gear or from a second gear to a third gear. The shortened neutral positions 115a, 115b then define the engaged gear (e.g., second or third gear).
[0028] In contrast to the shortened neutral positions 115a, 115b, gear shifting occurs in the neutral positions 115 via the adjacent gate. For example, in the first angular position P1, the first shift cable 131 is moved axially (e.g., a gear change is performed), while the second shift fork 132 remains in the neutral position 115 and does not perform a gear change.
[0029] For example only, the shift drum shown comprises two gates 111, 112, which are formed adjacent to one another along the axial direction on the surface of the shift drum 110. More or fewer gates can also be formed, which then engage the respective shift forks.
[0030] The engagement of the shift forks 131, 132 occurs, for example, via a projection 135a, 135b that extends into the respective gate 111, 112. The gates 111, 112 are designed, for example, as grooves (recesses) along which the projections 135a, 135b of the shift forks 131, 132 are guided. In the exemplary embodiment shown, the shift forks 131, 132 are fixed along the radial direction with respect to the shift rod 140 (a corresponding fixation is not shown), so that the engagement of the projections 135 necessarily leads to an axial displacement when the gates 111, 112 pass through a switching range 114.
[0031] Fig. 2 shows a cross-sectional view through a shift drum 110, 120 of a device for converting rotary into linear movements according to a further exemplary embodiment. The shift drum 110 can again be designed as shown in Fig. 1. However, the shift fork 131, 132 here comprises a cylindrical region 136 (cylindrical section) which forms a through-opening into which the shift drum 110 is inserted. In the cylindrical region 136, for example, an opening can be provided through which a pin is inserted, which extends as a projection 135 into the through-opening. When the shift drum 110 is inserted, this projection can then engage in one of the gates 111, 112. In this way, the shift fork 131, 132 is guided axially again.
[0032] The embodiment shown using the cylindrical region 136 offers the advantage that there is a positive connection between the shift fork 131, 132 and the shift drum 110, i.e. the shift fork 131, 132 cannot be moved along the radial direction (away from the shift rod 140) or only when the shift drum 110 is guided out of the cylindrical region 136. For example, the shift fork 131, 132 can be placed onto the shift drum 110 during production or the shift drum 110 can be inserted into the cylindrical region 136. It is understood that the cylindrical region 136 does not have to extend completely around the shift drum 110. Rather, a gap or the like can be formed to provide a certain degree of flexibility (e.g., to compensate for mechanical or thermal stresses).However, the cylinder area 136 can also be formed completely (360°) around the shift drum 110 in order to provide a firm hold.
[0033] Embodiments thus relate to two embodiments for the shift forks 131, 132: the shift forks 131, 132 comprise or do not comprise a cylindrical, enclosing region 136 into which the shift drums 110, 120 can be inserted, so that engagement in the gate(s) 111, 112 can take place via a projection 135 (e.g. a pin). If no cylindrical region 136 is present, the device in any case comprises a radial fixation of the shift forks 131, 132 in order to ensure the position from Fig. 1 in this case. It is understood that according to further embodiments, any combination of these two embodiments can also be present for the shift forks 131, 132.
[0034] Fig. 3 shows a device with a shift drum arrangement 110, 120 according to a further exemplary embodiment. In the exemplary embodiment shown, the shift drum arrangement comprises a first shift drum 110 and a second shift drum 120. The first shift drum 110 comprises a first gate 111 and the second shift drum 120 comprises a second gate 112. Each of the gates 111, 112 in turn comprises at least one neutral position 115, wherein the shifting ranges 114 of the first gate 111 and the shifting ranges 114 of the second gate 112 are formed at different angular ranges. In addition, the first shift drum 110 is arranged on a first shift rod 140a and the second shift drum 120 is arranged on a second shift rod 140b. The first shift rod 140a can, for example, be coupled in a rotationally fixed manner to the second shift rod 140b by means of a coupling 145 (e.g.via a screw-drive engagement or via a triangular / round, square / round, or polygonal / round engagement). It is understood that the shift rods 140 do not have to be designed as continuous rods, but can extend away from the shift drums 110, 120 as rod-shaped extensions or shift rod sections 140a, 140b. Furthermore, the embodiment shown comprises a first shift fork 131, which engages in the first gate 111 via the first projection 135a. The shift drum arrangement shown also comprises a second shift fork 132, which engages in the second gate 112 via a second projection 135b. The first shift fork 131 and the second shift fork 132 can in turn be designed as shown in Fig. 1 or alternatively comprise a cylindrical region 136 which encompasses the respective shift drum 110, 120, as described with Fig. 2.
[0035] The embodiment of Fig. 3 thus represents a modularly expandable shift drum assembly that can have additional shift drums connected in series. Depending on the number of gears to be shifted, a specific number of shift drums can be coupled together.
[0036] According to further embodiments, the first shift drum 111 or the second shift drum 112 can also have a plurality of gates, wherein a corresponding shift fork can engage in each gate in order to shift corresponding gears.
[0037] An advantage of the modular arrangement, as shown in Fig. 3, is that a variety of different transmissions with a different number of gears to be shifted can be manufactured using one technology. The shift drum assembly 110, 120 can be adapted so that any number of gears can be shifted. Likewise, the individual shift forks 131, 132 can be arranged at any position along the axial direction in order to adapt the shift drum assembly to existing transmission units.
[0038] According to further embodiments, the shift rods 140 are coupled to an electric motor or another rotary actuator (not shown in the figures) to provide the rotary movement. Likewise, according to further embodiments, sensors can be provided which, on the one hand, determine a rotational position of the shift rod(s) 140 or can sense axial positions of the shift forks 131, 132. The shift drum arrangement shown is designed to be used for an electronic transmission actuator unit of a commercial vehicle. The shift drum arrangement is accordingly long in the axial direction, for example, to provide a stroke of 10 mm or more (e.g., more than 15 mm or more than 20 mm), as is the case for transmissions in commercial vehicles. The shift drum itself therefore extends in the axial direction by at least 30 mm or more than 50 mm.According to further embodiments, the radius of the shift drum assembly 110, 120 can also be selected to be large enough to allow different shifting regions 114 to be formed on the large surface of the shift drum assembly 110, 120. With a correspondingly large surface area, a plurality of shifting regions can thus be accommodated on one shift drum 110, 120.
[0039] According to further embodiments, the shift forks 131, 132 are designed as pivotable shift forks (so-called rocking forks), wherein the pivotable shift forks enable tilting or pivoting of the shift forks 131, 132 (for example, along the axial direction or along the circumferential direction, respectively). The shift forks 131, 132 can be adapted to the specific transmission in terms of position or shape in order to effect gear shifting.
[0040] The features of the invention disclosed in the description, the claims and the figures may be essential for the realization of the invention both individually and in any combination.
[0041] LIST OF REFERENCE SYMBOLS
[0042] 110, 120 shift drum(s) of a shift drum arrangement
[0043] 111 , 112 Scenes
[0044] 114 switching range(s)
[0045] 115, 125 neutral position(s)
[0046] 131 ,132 shift forks
[0047] 135 projection, pin
[0048] 136 cylinder area
[0049] 140 shift rod, shift rod sections
[0050] 145 Coupling of shift rods
[0051] D rotational movement
[0052] A Linear movement (axial movement)
[0053] P1 , P2 angular positions
Claims
PATENT CLAIMS 1. A device for converting a rotary movement (D) into a linear movement (A) for an electronic transmission actuator of a commercial vehicle, characterized by a shift drum arrangement (110, 120) for executing the rotary movement (D); at least two gates (111, 112) on a surface of the shift drum arrangement (110, 120), each gate (111, 112) having at least one neutral position (115, 125); and at least two shift forks (131, 132) for executing the linear movement (A), the at least two shift forks (131, 132) each engaging in one of the gates (111, 112) in order to convert the rotary movement (D) of the shift drum arrangement (110, 120) into the linear movement (A).
2. Device according to claim 1, characterized in that the shift drum arrangement (110, 120) comprises the following: - a shift drum (110) with at least two gates (111, 112); or - two shift drums (110, 120) each having at least one link (111, 112) which are coupled in a rotationally fixed manner by means of a coupling (145).
3. Device according to claim 1 or claim 2, wherein the at least two gates comprise a first gate (111) with a first switching range (114) and a second gate (112) with a second switching range (114), and wherein the switching ranges (114) bring about the linear movement (A) during the rotary movement (D), characterized in that the first gate (111) has a first switching range (114) in a first angular range of the shift drum arrangement (110, 120), where the second gate has a neutral position (125), and the second gate (112) has a second switching range (114) in a second angular range of the shift drum arrangement (110, 120), where the first gate (110) has a neutral position (115).
4. Device according to one of the preceding claims, which further comprises a shift rod (140) which is rotationally coupled to the shift drum arrangement (110, 120) for transmitting the rotational movement (D), characterized in that at least one shift fork of the at least two shift forks (131, 132) has a cylinder region (136) with a radially inwardly extending projection (135), wherein the shift drum arrangement (110, 120) is at least partially insertable into the cylinder region (136) in order to extend in a form-fitting manner around the shift drum arrangement (110, 120), while the projection (135) engages in one of the guides (111, 112).
5. Device according to one of the preceding claims, characterized in that at least one shift fork of the at least two shift forks (131, 132) has a projection (135) which engages in one of the gates (111, 112) without a section of the at least one shift fork extending in a form-fitting manner around the shift drum arrangement (110, 120).
6. Device according to one of the preceding claims, characterized in that at least one of the at least two shift forks (131, 132) is a pivotable shift fork.
7. Device according to one of the preceding claims, characterized in that the two links have a stroke of more than 10 mm or more than 15 mm.
8. Electronic transmission actuator unit for a commercial vehicle with an electromotive transmission actuator, characterized by a device according to one of claims 1 to 7, wherein a transmission actuator is coupled to the device to provide the rotary movement.
9. Commercial vehicle, in particular a truck, characterized by an electronic transmission actuator according to claim 8.