Power lift with electric drive unit

Abstract

The invention relates to a power lift for a vehicle, comprising at least one base frame (1) for securing the power lift to the vehicle, a carrying and drive unit (2) for carrying and driving an attachment, and at least one upper link (3) and at least one lower link (4), said carrying and drive unit (2) being hinged on the base frame (1) via upper links (3) and lower links (4). The power lift comprises at least one electric drive (5) for driving the attachment.

Description

Power lift with electric drive unit

[0001] The present invention relates to a power lift for a vehicle, and to a vehicle, in particular an electric municipal vehicle, with at least one such power lift. State of the art

[0002] Power lifts are generally known from the prior art. These are used on (commercial) vehicles to couple and lift attachments (work implements), such as sweepers, mowers, cutter bars, mulchers, snow blowers and (snow) plows.

[0003] To power corresponding attachments, especially sweepers, mowers, cutter bars, mulchers, and snow blowers, the vehicle's power take-off (PTO) is typically used. The attachment is connected to the vehicle's PTO via a driveshaft, thus providing the necessary drive power. However, this requires certain structural features on the vehicle, particularly at the front and rear, and therefore represents a limitation in terms of vehicle design.

[0004] Furthermore, this type of power supply to the implement requires a force-transmitting connection between the vehicle and the implement, which must function reliably even with relative movements between the vehicle and the implement mediated by the power lift. In particular, if these relative movements change the distance between the vehicle's power take-off (PTO) shaft and the implement's connection point, drive shafts with two universal joints and a thrust joint for longitudinal compensation must be used. However, with increasing articulation angle and increasing torque, the efficiency decreases, and the wear and tear or failure probability of such drive shafts increases.

[0005] Alternatively, attachments with their own drive system can be used. Naturally, such attachments are more expensive than those without their own drive. Object of the invention

[0006] The present invention therefore aims to enable a particularly efficient and reliable coupling of an attachment to a commercial vehicle. A further objective is to enable the supply of drive energy to the attachment with high efficiency and essentially independently of any relative movement or working position of the attachment. Further objectives of the invention will become apparent from the description. Description of the invention

[0007] One object of the invention is solved by a power lift for a vehicle, in particular for a commercial vehicle, for example a municipal vehicle, comprising at least a. a base frame for attaching the power lift to the vehicle, b. a support and drive unit for carrying and driving an attachment, and c. at least one top link and at least one lower link, wherein the support and drive unit is articulated (or pivotably connected) to the base frame via top link and lower link, and wherein the power lift comprises at least one electric drive for driving the attachment.

[0008] Unlike conventional power lifts, the power lift according to the invention therefore includes its own electric drive. The electric drive is mounted on an element of the power lift and is thus an integral part of the power lift. Since the respective implement, which is to be coupled to the vehicle via the power lift, is supplied with drive energy by this electric drive, relative movements between the implement and the vehicle no longer play a role with regard to the supply of drive energy to the implement; it only matters whether and how the relative position of the implement changes with respect to a power take-off shaft of the electric drive of the power lift. In addition, the power lift according to the invention, which can be used as a front and rear power lift, enables the use of such (driven) implements even on vehicles that do not have a corresponding power take-off.

[0009] The power lift according to the invention can be used, in particular, as a front power lift for electric vehicles and can be designed for a lifting capacity of up to 1000 kg. The base frame can be a welded construction that serves to absorb and transmit forces. The base frame provides the connection to a vehicle frame and can include supply connections, in particular connections for hydraulics, water, and electricity (implement control, attachments). A working cylinder, for example, a hydraulic cylinder (200 bar), can be provided on the base frame for extending the lower link arms. The support and drive unit enables the attachment to be mounted on the power lift and the attachment to be supplied with drive energy.It can be designed with a (multi-part, in particular two-part) frame construction, which frame construction is articulated to the base frame via upper and lower links, and on which frame construction the electric drive – or its components, such as the electric motor, gearbox, and motor control – is / are mounted. The support and drive unit can also have (optionally standardized) attachment points for attaching the implement to the power lift. The lower link(s) can be rigidly designed and, preferably electro-hydraulically, adjustable or pivotable on the base element to allow height adjustment of the support and drive unit; alternatively or additionally, the lower link can be mounted on the base frame in such a way that the support and drive unit is suspended from the base frame.The lower link(s) can be connected to the base frame and the support and drive unit via ball joints. The upper link(s) can be length-adjustable, for example electro-hydraulically, to allow stabilization and position adjustment of the implement at a height determined by the lower link.

[0010] According to a preferred embodiment of the invention, the support and drive unit comprises at least one base element and an attachment element detachably connected to the base element. Preferably, the electric drive is mounted on the base element, and the attachment element has mounting points for attaching the attachment to the power lift. The base element and / or the attachment element may be designed in a frame-like form.

[0011] This two-part design of the support and drive unit proves advantageous, firstly, with regard to mounting the attachment to the power lift; in particular, the attachment element can be optimally designed for this purpose, for example, by having appropriate (standardized) mounting points. Secondly, the base element can be specifically designed to accommodate the electric drive and its Components are designed for connecting the top and bottom links, as well as for a user-friendly and detachable connection to the attachment element, adaptable to the specific application and implement used. The base element, which serves to absorb force and torque, can be made of steel and be essentially plate-shaped or have a plate-shaped section. Preferably, several screw points (through holes or threaded holes) can be provided on both sides for height-adjustable attachment of the mounting element (mounting plate) to the base element. This allows for adjustment of the working height of the respective implement. The mounting element itself can also be made of steel (sheet metal) and be essentially plate-shaped or have a plate-shaped section.

[0012] According to a preferred embodiment of the invention, the fastening points are formed by bolts and / or elongated holes.

[0013] Preferably, the mounting element, which can generally be frame-like, can be reinforced or constructed in the area of ​​the elongated holes (for example, by double sheet metal). Particularly preferably, the mounting element has two bolts on its upper surface for suspending the attachment and two elongated holes in a lower end face, which elongated holes are preferably accessible from one side via an edge region of the mounting element. The combination of corresponding bolts for suspension and elongated holes for fixing the attachment enables a particularly reliable, yet time-saving and safe attachment of the attachment to the power lift according to the invention.

[0014] According to a preferred embodiment of the invention, the base element and / or the attachment element comprises or comprise fastening means to connect the attachment element to the base element in a detachable manner, at least in a first position and in a second position.

[0015] This makes it possible to precisely adjust the height of the attachment on the power lift. For example, the attachment can be operated in a first height position when the attachment element is connected to the base element in the first position, and in a second height position, which, viewed vertically, is higher than the first height position when the attachment element is connected to the base element in the second position. By providing a third and further positions in which the attachment element can be mounted on the base element of the support and drive unit, the height of the working position of the attachment can be adjusted with any desired precision. Thus, the power lift becomes suitable for use with various attachments and vehicles.

[0016] According to a preferred embodiment of the invention, the electric drive comprises an electric motor which drives a power take-off shaft of the power lift. Preferably, the electric motor has a speed range of 0-1500 revolutions per minute and can be operated in both directions of rotation.

[0017] Because the electric drive of the power lift comprises an electric motor, the power lift according to the invention, or the attached implement, can be operated extremely quietly. In conjunction with electric commercial vehicles, a particularly high efficiency can also be achieved. Furthermore, electric motors can be designed to be relatively compact, thus enabling a particularly well-protected housing of the electric motor on the power lift, especially in the area between the support and drive unit and the base frame, surrounded by the upper and lower links. In this way, the electric motor can be protected particularly effectively against mechanical damage.

[0018] According to a preferred embodiment of the invention, the power take-off shaft is accessible via a front-side recess of the attachment element in order to enable a functional connection with the attachment.

[0019] The power take-off (PTO) shaft serves to supply the mechanical drive energy generated by the drive unit, particularly the electric motor, to the implement. Because the PTO shaft is located on the same part of the power lift to which the implement itself is attached, a particularly simple, reliable, and efficient power transmission is ensured. The PTO shaft can be arranged entirely within the power lift, specifically within the support and drive unit, and thus protected from unwanted external forces. The end-face recess, provided in this embodiment on an end face of the support and drive unit (facing the implement during operation), allows easy access to the PTO shaft for establishing the operative connection that transmits the drive energy.

[0020] According to a preferred embodiment of the invention, the electric drive comprises a gearbox via which the electric motor is mounted on the base element.

[0021] The gearbox allows the power output via the power take-off shaft to be optimized within the speed range of the electric motor. This is particularly relevant in the invention. The preferred speed range of 0-1500 rpm enables particularly efficient operation of the attachment. Furthermore, mounting it as a gearbox-motor unit on the base element allows for a particularly compact and space-saving arrangement of the electric drive components on the support and drive unit.

[0022] According to a preferred embodiment of the invention, the electric motor and the gearbox are provided on a side of the base element facing away from the attachment element.

[0023] Thus, the electric motor-gearbox unit is located on one side of the base element, while the attachment element—and therefore, in operation, the implement—is located on the other side. The electric motor-gearbox unit and the attachment element—or, in operation, the implement—are therefore separated by the base element. This results in particularly well-protected housing of the electric drive components, especially since the gearbox and electric motor are better protected from kicked-up soil, stones, etc., during operation.

[0024] According to a preferred embodiment of the invention, the electric drive comprises a motor control unit, which is preferably mounted on the base element. This motor control unit can, in particular, be configured to communicate with control elements of the vehicle and / or the attachment.

[0025] This allows for the optimization of the operating condition of the implement, the electric drive of the power lift, and / or the vehicle. Mounting the motor control unit directly to the base element significantly reduces the susceptibility of the electric drive to failure, as the motor control unit is thus located in close proximity to the electric motor and the gearbox – i.e., the components of the electric drive that need to be controlled. This allows the corresponding cable connections to be kept short, and at least these, preferably all, components of the electric drive can be housed on the base element, protected from damage, for example, in a common housing.

[0026] According to a preferred embodiment of the invention, the motor control unit is configured to regulate the electric drive depending on the vehicle's operating state. For this purpose, the motor control unit can... It must be equipped to communicate with components of the vehicle, in particular the vehicle's engine control unit.

[0027] In particular, this makes it possible to operate the attachment depending on the vehicle's driving speed or other operating parameters. For example, a mower or sweeper can be operated at lower power at lower driving speeds, while the power can be increased at higher speeds. This design thus improves the operating efficiency of the attachment and reduces its wear.

[0028] According to a preferred embodiment of the invention, the motor control unit is configured to regulate the vehicle's drive system depending on the operating state of the electric drive. For this purpose, the motor control unit can be configured to communicate with components of the vehicle, in particular with another motor control unit.

[0029] For example, the vehicle's driving speed, or other operating parameters, can be controlled depending on the power consumption of the attachment. This makes it possible to operate the entire system—the attachment, the power lift, and the vehicle—as efficiently as possible.

[0030] Furthermore, the motor control of the electric drive also enables fully automatic operation of the attachment, thereby increasing the vehicle's user-friendliness. However, the electric drive with motor control according to the invention also lays the foundation for the use of attachments in conjunction with autonomous vehicles.

[0031] According to a preferred embodiment of the invention, the base frame includes connections for supplying the attachment, in particular hydraulic connections, water connections and / or electrical connections.

[0032] Such connections can be powered by the vehicle's existing supply lines, further enhancing user-friendliness. Specifically, when attaching the implement to the vehicle using the power lift, a user (e.g., the driver) can make all necessary connections (such as water and electrical connections for a sweeper) without having to interact with any vehicle components other than the power lift. All required connections are provided directly at the vehicle's power lift. This increases handling safety and ease of use. Furthermore, corresponding connecting lines to the vehicle's power lift can be easily connected. The attachment can be kept relatively short, which increases operational safety.

[0033] According to a preferred embodiment of the invention, it is provided that at least one, preferably all, top links are designed to be length-adjustable.

[0034] In particular, electro-hydraulic length adjustment is conceivable. This allows for even more precise adjustment of the implement's working position, specifically its tilting position, via the top link(s). The implement's working height can be adjusted via the lower link(s).

[0035] According to a preferred embodiment of the invention, the at least one lower link comprises at least a. a first section, at which first section the lower link is rotatably connected to the support and drive unit, b. a second section, which second section tapers from the first section and at which second section the lower link is rotatably connected to the base frame, and c. a third section, which third section extends in a direction transverse to the first section and / or the second section, projects from the first section or the second section and at which third section the lower link is connected to an actuating element.

[0036] Thus, the third section, which preferably projects from the second section, can be used as a lever by which the actuating element, such as a hydraulic, pneumatic, or electric cylinder, can rotate the lower link to raise or lower the support and drive unit. This lower link design has proven to be particularly ergonomic and simultaneously allows for a particularly compact construction of the power lift. In a two-arm version, in which the lower link is formed by two parallel arms connected by a crossbar, the first section has two receptacles for connecting the lower link to the support and drive unit, and the second section has two receptacles for connecting the lower link to the base frame. This two-arm design enables particularly stable and reliable guidance of the support and drive unit.

[0037] In a preferred embodiment, the power lift comprises exactly one lower link of the type described above.

[0038] This allows the design of the power lift to be kept particularly simple, while at the same time ensuring high stability and load-bearing capacity.

[0039] One object of the invention is solved by a vehicle, in particular a municipal vehicle, comprising a front power lift and / or a rear power lift, wherein the front power lift and / or the rear power lift is / are designed by the power lift according to the invention in accordance with one of the embodiments described above.

[0040] The statements made above in connection with the power lift apply analogously to this vehicle equipped with the power lift according to the invention. Brief description of the characters

[0041] The invention is explained in more detail below with reference to the drawings. However, the following explanations are neither intended to restrict nor to provide a complete account of the invention. The drawings show: Fig. 1 shows a schematic representation of the power lift, Fig. 2 shows another schematic representation of the power lift, Fig. 3 shows a schematic representation of the basic frame, Fig. 4 shows a schematic representation of the lower link, Fig. 5 shows a schematic representation of the carrying and drive unit, Fig. 6 shows another schematic representation of the carrying and drive unit, Fig. 7 shows a schematic representation of the basic element of the carrying and drive unit, Fig. 8 shows a schematic representation of the attachment element of the support and drive unit and Fig. 9 shows another schematic representation of the attachment element of the carrying and drive unit. Ways to implement the invention

[0042] Figures 1 and 2 show the power lift according to the invention in one embodiment.

[0043] The power lift initially comprises a base frame 1 (see Fig. 3), which serves to attach or mount the power lift to a vehicle, in particular a commercial vehicle such as a municipal vehicle. A support and drive unit 2 (Figs. 5, 6, 7, 8 and 9) is articulated to the base frame 1 via a lower link 4 (see Fig. 4) and – here – two upper links 3. The support and drive unit 2 serves to support and drive an attachment, such as a sweeper, a cutter bar, a mulcher, or a snow blower. According to the invention, the power lift has at least one electric drive 5, which – here – is mounted on the support and drive unit 2.

[0044] The base frame 1, shown in detail in Fig. 3, comprises a mounting section 19, which serves to mount the base frame 1 to the respective vehicle, and a connection section 20, which has linkage mounts 21 for the top link 3 and the lower link 4. The base frame 1 also has a bracket 22 for an actuating element, which here is designed as a hydraulic cylinder 23 and serves to actuate the lower link 4. Furthermore, recesses 24 are provided for connections to supply the implement with electricity, water, or to supply a hydraulic system of the implement.

[0045] The lower link 4, which serves to adjust the height of the support and drive unit 2, is shown in detail in Fig. 4. A two-armed version is depicted, in which the lower link 4 is formed by two parallel link arms 26 connected by a crossbar 25. In a first section 16 of the lower link 4, two receptacles are formed for connecting the lower link 4 to the support and drive unit 2; in a second section 17, two receptacles are provided for connecting the lower link 4 to the base frame 1. A third section 18 of the lower link 4, which projects approximately orthogonally from the second section 17, is used as a lever. This lever allows the actuating element, designed here as a hydraulic cylinder 23, to rotate the lower link 4 about the corresponding link receptacle 21 in order to raise or lower the support and drive unit.

[0046] Figures 5 and 6 show the support and drive unit 2 in detail. The support and drive unit 2 comprises a base element 6 and an attachment element 7, with several through-holes 27 on each side of both the base element 6 and the attachment element 7 for height-adjustable, detachable fastening (e.g., screwing) of the attachment element 7 to the base element 6. Figures 5 and 6 show the support and drive unit 2 in a state where the base element 6 and the attachment element 7 are assembled at a specific height; fastening elements (e.g., screws) passing through the through-holes 27 are not shown. The base element 6 is shown as a separate component in Figure 7; the attachment element 7 is shown separately in Figures 8 and 9 – in a perspective view (Figure 8) and a front view (Figure 9).

[0047] The mounting element 7 is provided with attachment points 8 for attaching the implement to the power lift. In the illustrated embodiment, these attachment points 8 are formed on the one hand by bolts 9, which project vertically in an upper circumferential region of the mounting element 7; on the other hand, further attachment points 8 are provided in a lower region of an end face of the mounting element 7, formed by elongated holes 10, which are open to a lateral circumferential region of the mounting element 7. A recess 13 is also provided in the end face of the mounting element 7, through which a power take-off shaft 13 of the power lift is accessible (from the outside).

[0048] The base element 6 (see also Fig. 7) has linkage mounts 21 for the two top links 3 and the lower link 4 on an inner side facing away from the attachment element 7. An electric motor 11 and a gearbox 14 are also mounted on this same inner side, with the power take-off shaft 12 serving to transmit drive energy to the implement and, for this purpose, protruding from the gearbox 14 and through an opening in the base element 6. A motor control unit 15 for the electric motor 11 is also mounted in a lateral circumferential area of ​​the base element 6.

[0049] The functioning of the power lift according to the invention, as described above, can be summarized as follows:

[0050] The power lift, attached to the vehicle via the base frame 1, is designed to couple and drive an implement. For this purpose, a connection is first established – for example, by means of a driveshaft – between the implement and the power take-off shaft 12 of the power lift to supply the implement with drive energy. The implement is then attached to the frame using the bolts 9. Attachment element 7 is suspended and screwed to the attachment element 7 using the elongated holes 10 in order to couple the attachment to the support and drive unit 2 of the power lift. The coupling and the establishment of the functional connection can also be carried out in a single (simultaneous) operation. Prior to this, a working height of the attachment can be preset by adjusting the height of attachment element 7 on the base element 6.

[0051] To raise and lower the support and drive unit 2 during vehicle operation, the lower link 4 can be rotated around the corresponding linkage 21 of the base frame 1 by means of the hydraulic cylinder 23. Corresponding control signals can, for example, originate from the vehicle. In this way, the working height of the implement can be adjusted during operation. To additionally set a tilting position of the implement, the length of the top link 3 can be varied – for example, also electro-hydraulically – which tilts the base element 6 of the support and drive unit 2 (from the vertical). The attachment element 7, which is (detachably) connected to the base element 6, then also performs a corresponding tilting movement, which is thus transmitted to the attached implement.

[0052] Since the drive energy for the attachment comes from the electric drive 5 located directly on the support and drive unit 2, there are no relative movements between the attachment and the electric motor 11 during operation of the attachment, at least not to a practically relevant extent. This results in highly efficient transmission of drive energy to the attachment, especially since (particularly through height adjustment using the attachment element 7) the deflection angle of the shaft or drive shaft used to transmit the drive energy can be kept to a minimum, thus enabling virtually lossless transmission of drive energy to the attachment. Furthermore, extremely reliable coupling of the attachment to the (commercial) vehicle is ensured, as the shaft or drive shaft used to transmit the drive energy is...The drive shaft can be kept short and guided mostly, preferably completely, within the attachment and / or the power lift, thus making the susceptibility to damage from external forces extremely low. Reference symbol list 1 Basic frame 2 Carrying and drive unit 3 top links 4 lower links 5 electric drive 6 Basic element 7 Add-on element 8 attachment points 9 bolts 10 elongated holes 11 Electric motor 12 PTO 13 recess 14 gearboxes 15 Engine control 16 first section 17 second section 18 third section 19 Assembly section 20 Connection section 21 Handlebar mount 22 bracket 23 hydraulic cylinders 24 exceptions 25 cross brace 26 handlebar arm 27 Through hole

Claims

Patent claims 1. Power lift for a vehicle, comprising at least a. a base frame (1) for attaching the power lift to the vehicle, b. a support and drive unit (2) for supporting and driving an implement, and c. at least one top link (3) and at least one lower link (4), wherein the support and drive unit (2) is articulated to the base frame (1) via top link (3) and lower link (4), wherein the power lift comprises at least one electric drive (5) for driving the implement.

2. Power lift according to claim 1, characterized in that the support and drive unit (2) comprises at least one base element (6) and an attachment element (7) detachably connected to the base element (6), wherein the electric drive (5) is mounted on the base element (6) and wherein the attachment element (7) has attachment points (8) for attaching the attachment to the power lift.

3. Power lift according to claim 2, characterized in that the fastening points (8) are formed by bolts (9) and / or elongated holes (10).

4. Power lift according to one of claims 2 or 3, characterized in that the base element (6) and / or the attachment element (7) comprises or comprise fastening means to detachably connect the attachment element (7) to the base element (6) at least in a first position and in a second position.

5. Power lift according to one of claims 1 to 4, characterized in that the electric drive (5) comprises an electric motor (11) which electric motor (11) drives a power take-off shaft (12) of the power lift.

6. Power lift according to claim 5, characterized in that the power take-off shaft (12) is accessible via a front-side recess (13) of the attachment element (7) in order to enable a functional connection with the attachment.

7. Power lift according to one of claims 5 or 6, characterized in that the electric drive (5) comprises a gearbox (14) via which gearbox (14) the electric motor (11) is mounted on the base element (6).

8. Power lift according to claim 7, characterized in that the electric motor (11 ) and the gearbox (14) are provided on a side of the base element (6) facing away from the attachment element (7).

9. Power lift according to one of claims 1 to 8, characterized in that the electric drive (5) comprises a motor control (15), which motor control (15) is preferably mounted on the base element (6).

10. Power lift according to claim 9, characterized in that the motor control (15) is configured to regulate the electric drive (5) depending on an operating state of the vehicle.

11. Power lift according to one of claims 9 or 10, characterized in that the motor control (15) is configured to regulate a vehicle drive of the vehicle depending on an operating state of the electric drive (5).

12. Power lift according to one of claims 1 to 11, characterized in that the base frame (1) includes connections for supplying the attachment, in particular hydraulic connections, water connections and / or electrical connections.

13. Power lift according to one of claims 1 to 12, characterized in that at least one, preferably all, top link(s) (3) is / are designed to be length-adjustable.

14. Power lift according to one of claims 1 to 13, characterized in that the at least one lower link (4) comprises at least a. a first section (16) in which the lower link (4) is rotatably connected to the support and drive unit (2), b. a second section (17) in which the second section (17) tapers from the first section (16) and in which the lower link (4) is rotatably connected to the base frame (1), and c. a third section (18) in which the third section (18) extends transversely to the first section (16) and / or to the second section (17). extending in the direction of travel, projecting from the first section (16) or from the second section (17), and at which third section (18) the lower link (4) is connected to an actuating element, in particular to a hydraulic cylinder (23).

15. Vehicle, in particular municipal vehicle, comprising a front linkage and / or a rear linkage, wherein the front linkage and / or the rear linkage is / are formed by the linkage according to one of claims 1 to 14.

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