REACH TRUCK

Description

[0001] The invention relates to a reach truck with a drive part and a load part, wherein the drive part comprises a drive frame with two mutually parallel wheel arms and a base frame connecting the wheel arms to one another, wherein a first guide means is arranged on each of the wheel arms, wherein the load part comprises a mast holder with two side arms running parallel to one another and a cross member connecting the side arms to one another, wherein a second guide means is arranged on each of the side arms, wherein the side arms of the mast holder extend parallel to the wheel arms of the drive frame, so that in each case one of the side arms runs adjacent to one of the wheel arms, wherein in each case the first guide means of a wheel arm interacts with the second guide means of the adjacent side arm in such a way that the mast holder is guided movably on the wheel arms.

[0002] Reach trucks of this type are used to move goods, particularly in confined spaces. Unlike cantilever forklift trucks, stability on reach trucks is not generally achieved by a counterweight, but by outriggers extending from the front of the reach truck. These outriggers usually form part of the reach truck's drive frame, and a motor, such as an electric motor including batteries, can also be located in the drive frame. The load section, which usually comprises a mast holder and an extendable mast arranged on the mast holder, is guided along the outriggers via guide means. This guidance is provided by guide means arranged on the side arms of the mast holder and enables the mast holder to be moved along the outriggers of the drive frame. By guiding the mast holder on the outriggers of the drive section, the load section is guided by the outriggers orsupported on the ground by wheels arranged on the wheel arms.

[0003] The wheel arms are therefore subjected to a force dependent on the weight of the goods transported on the load section. Depending on the extension position of the mast holder, this force causes the wheel arms to spread apart to varying degrees along the wheel arms. This can, among other things, endanger the transport of the goods and result in damage to the reach truck.

[0004] To counteract such spreading of the wheel arms, the wheel arms can be connected to one another in the area of ​​the base frame using various reinforcing means. For example, a connecting plate extending parallel to the floor can be provided, which - in addition to the base frame - connects the wheel arms to one another. A cross member can also be provided, formed, for example, by another connecting plate that extends perpendicular to the floor from one wheel arm to the other. However, such reinforcing means are complex to install, especially as welded assemblies. In addition, such reinforcing means essentially only counteract the spreading of the wheel arms in the area of ​​the base frame, while spreading is not optimally counteracted at the free ends of the wheel arms.

[0005] US Pat. No. 5,641,261 discloses a reach truck whose frame has two support arms. A mast holder K is movably mounted on the frame thanks to the support arms. Guide rails are formed on the support arms, in which the mast holder runs via guide rollers. Extending outward from the upper end of each side arm of the mast holder is a bracket with a stabilizing roller at its end. The stabilizing roller thus engages behind the guide rail of the support arm.

[0006] DE 29622546 U1 discloses a forklift with a mast with reduced jerking movements. The forklift has a movable base that can be moved along one leg. The mast is mounted on support rollers and clamp rollers. This document discloses the preamble of claim 1.

[0007] From JP 2004075303 A a reach truck is known whose lifting frame is mounted on sliding elements in the wheel arms.

[0008] Based on the described prior art, the invention is based on the object of providing a reach truck which, with simple manufacture, reliably prevents the wheel arms from spreading out even with large loads.

[0009] The invention solves the problem by the subject matter of claim 1. Advantageous embodiments are the subject matter of the subclaims, the description and the figures.

[0010] According to the invention, the object is achieved in that a first bearing element is arranged on each of the wheel arms and a second bearing element is arranged on each of the side arms, wherein adjacent wheel arms and side arms are in engagement with one another via their respective bearing elements in such a way that the second bearing elements limit a movement of the wheel arms away from one another to the outside.

[0011] The mast holder, with its cross member and the side arms extending from it, forms a U-shape, as does the drive frame with its base frame and the outriggers extending from it. As explained at the beginning, the mast holder and thus the load section of the reach truck is guided via the outriggers to the drive frame and thus to the drive section. For this purpose, first guide means are provided on the outriggers, which interact with second guide means arranged on the side arms. Each side arm is guided to the adjacent outrigger arm via the respective first and second guide means. The U-shaped mast holder is thus mounted within the U-shaped drive frame. Looking in the direction of travel of the reach truck, this results in a left pair of arms, consisting of the left outrigger arm and the left side arm, and a right pair of arms, consisting of the right outrigger arm and the right side arm.The mast holder allows the entire load section to be extended in the direction of travel of the reach truck and retracted against the direction of travel of the reach truck, with the side arms moving along the wheel arms.

[0012] According to the invention, in addition to the first and second guide means, which allow the mast holder to be moved within the wheel arms, first and second bearing elements are provided. Both the left and the right arm pair therefore each comprise first and second bearing elements, via which the left wheel arm engages with the left side arm and the right wheel arm engages with the right side arm. Consequently, the left wheel arm engages with its first bearing element with the second bearing element of the left side arm, and the right wheel arm engages with its first bearing element with the second bearing element of the right side arm. According to the invention, the second bearing elements arranged on the side arms interact with the first bearing elements arranged on the wheel arms in such a way that any movement of the wheel arms away from one another towards the outside is limited.The second bearing elements engage with the first bearing elements, for example in a clamping manner, so that the mast holder holds the wheel arms of the drive frame together with its side arms. If a weight is now placed on the load part, for example on a mast connected to the mast holder, its weight is distributed across the wheel arms, resulting in a force that spreads the wheel arms apart. This spreading force pushes the wheel arms away from each other and outwards, i.e. in opposite directions on an axis that is perpendicular to the axis of movement of the mast holder and parallel to the ground. The second bearing elements on the side arms of the mast holder counter this force and thus prevent the wheel arms from spreading outwards. The first bearing elements engage with the second bearing elements in such a way that the mast holder can still be moved relative to the wheel arms.Thus, the second bearing elements between the wheel arms form reinforcements that move along the wheel arms with the mast holder—and consequently with the transported load. Thus, the bearing according to the invention always acts as a reinforcement at the point where the greatest spreading force acts on the wheel arms. Advantageously, the invention thus allows for a reliable connection of the wheel arms not only in the area of ​​the base frame but also across the entire length of the wheel arms.

[0013] According to the invention, the first bearing elements each have an outward-facing running surface and the second bearing elements each have at least one running element running along the respectively adjacent running surface, or the second bearing elements each have an inward-facing running surface and the first bearing elements each have at least one running element running along the respectively adjacent running surface. It can therefore be provided, for example, that the first bearing element of the left-hand wheel arm comprises an outward-facing running surface, while the second bearing element arranged on the left side arm comprises at least one running element that runs along the running surface of the left-hand wheel arm. The same then applies to the right-hand arm pair consisting of the right-hand wheel arm and the right side arm.Alternatively, it is conceivable for the second bearing element of the left side arm to comprise an inward-facing running surface, while the first bearing element of the left support arm comprises at least one running element which runs along the running surface of the left side arm. The same then applies here for the right pair of arms. Outward-facing here refers to a direction laterally away from the reach truck in the direction of the force spreading the support arms. Inward-facing describes the opposite direction. According to the invention, the interacting first and second bearing elements are therefore formed by running surfaces along which at least one running element each runs. The running surfaces always point away from the support arms or side arms in such a way that the running elements grip behind the running surfaces and thus limit the support arms from spreading outwards away from each other.For example, if the first bearing elements each have an outward-facing running surface, the second bearing elements can extend from the inner side arms through or past the corresponding running surfaces in such a way that the running elements can come into contact with the running surfaces facing away from the side arms. This ensures the aforementioned clamping support in a particularly simple manner.

[0014] According to the invention, the running elements each have a roller carrier protruding in the direction of the adjacent running surface, each with at least one roller running along the respective running surface. As explained above, the running elements extend in the direction of the corresponding running surfaces. For this purpose, a roller carrier protruding in the direction of the adjacent running surface can be provided, which roller carrier has at least one roller at its free end. The roller carrier protruding in the direction of the respective running surface can extend through the running surface or past it, so that the at least one roller can run along the respective running surface. If the running surfaces form, for example, part of the first bearing elements, the roller carriers can be attached to the side arms as part of the second bearing elements and extend from the inner side arms towards the outer wheel arms.Such rollers allow for particularly simple and low-friction engagement of the bearing elements with each other. Alternatively, other running elements, such as sliding elements, can be used instead of rollers.

[0015] According to the invention, the roller supports each comprise at least one L-shaped angle piece, wherein the L-shaped angle piece extends from the respective side arm in the direction of the respective adjacent wheel arm or wherein the L-shaped angle piece extends from the respective wheel arm in the direction of the respective adjacent side arm, wherein the at least one roller is arranged at a free end of the L-shaped angle piece. According to this embodiment, the above roller supports each have an L-shaped angle piece, which is fastened at one end to the respective side arm or wheel arm and has at its free end at least one roller which runs along the corresponding outwardly facing running surface of the respective wheel arm or side arm. Are the L-shaped

[0016] If angle pieces are arranged as part of the second bearing elements on the side arms, the L-shaped angle pieces engage behind the outer wheel arms of the drive frame with their free ends in a clamping manner. If the L-shaped angle pieces are arranged as part of the first bearing elements on the wheel arms, the L-shaped angle pieces engage behind the inner side arms with their free ends in a clamping manner. If the wheel arms move outwards from each other due to a high load on the load section, the rollers arranged at the free ends of the L-pieces generate a corresponding counterforce and thus prevent the wheel arms from spreading apart.

[0017] According to a further embodiment, the rotation axes of the rollers run perpendicular to a floor supporting the reach truck and parallel to the running surfaces during operation of the reach truck. The rollers are therefore mounted on the respective roller carrier such that their rotation axes are arranged perpendicular to a floor supporting the reach truck and parallel to the running surfaces. Thus, the rollers can run along the forward-facing running surfaces. In particular, the rotation axes of the rollers can be perpendicular to the rotation axes of the guide rollers.

[0018] According to one embodiment, the first guide means are each arranged on the inner sides of the wheel arms and the second guide means are each arranged on the outer sides of the side arms, wherein the respective inner side of a wheel arm faces the respective outer side of the adjacent side arm. Preferably, the first guide means each have a guide rail and the second guide means each have at least one guide roller, wherein the guide rollers of the respective second guide means are each guided on the adjacent guide rail of the first guide means. The wheel arms can therefore have guide rails on their inner sides, on which the guide rollers of the respective adjacent side arm are guided. Thus, for example, the left side arm can have one or more guide rollers on its outer side facing the left wheel arm, which are guided on the opposite guide rail. The same applies to the right pair of arms.The guide rails can extend from the wheel arms toward the side arms. In particular, the side arms can each have at least two guide rollers, which rest on the respective guide rail of the respective wheel arm from opposite sides. This allows the side arms, and consequently the mast holder, to be securely held to the wheel arms despite their ability to move relative to the wheel arms.

[0019] According to a further embodiment, the rotation axes of the guide rollers run horizontally to a floor supporting the reach truck. Thus, the guide rollers can run along the guide rails, which also extend horizontally to the floor and point away from the inside of the support arms. In particular, the rotation axes of the guide rollers can be arranged perpendicular to the running surfaces of the bearing elements. The guide rollers can move, in particular, in a plane perpendicular to the track rollers. The guide rollers serve to securely hold and guide the mast holder on the support arms, while the track rollers of the support elements merely serve to counteract the spreading of the support arms.

[0020] According to a further embodiment, spacers are arranged on the inner sides of the wheel arms and / or on the outer sides of the side arms. The spacers ensure that adjacent wheel arms and side arms only touch each other over a small surface area. In particular, the spacers serve to prevent the wheel arms from being pulled too close to the side arms due to the bearing elements according to the invention.

[0021] If guide rails projecting in the direction of the side arms are provided on the inside of the wheel arms, the spacers can be arranged in particular on the free ends of the guide rails projecting in the direction of the respective side arm and come into contact with the opposite side arms.

[0022] According to a further design, the base frame and the two wheel arms are welded together, or the base frame and the two wheel arms are manufactured together in a single casting process, or the base frame is cast and the two side arms are welded to the cast base frame. In particular, manufacturing the base frame together with the wheel arms in a single casting process is particularly simple and enables a particularly stable drive frame. This also counteracts the wheel arms from spreading apart.

[0023] According to a further embodiment, the wheel arms are connected to the base frame via connecting areas that partially extend along the wheel arms. The wheel arms can thus be connected to the base frame along a longitudinal direction of the wheel arms in a plane parallel to the ground. Such a connection between the wheel arms and the base frame additionally counteracts any movement of the wheel arms away from each other.

[0024] The invention is explained below with reference to figures. Figure 1a perspective view of a reach truck, Figure 2a perspective view of a drive frame including the mast holder mounted therein, Figure 3the drive frame from Fig. 2 in a schematic exploded view, Figure 4 the right wheel arm from Fig. 3 in a second view, Figure 5 the mast holder from Fig. 3 in a perspective view, Figure 6 the mast from Fig. 3 in a perspective view, Figure 7a-d different schematic views of the drive frame from Fig. 3 , Figure 8the drive frame from Fig. 1 including the mast holder mounted therein in a plan view, Figure 9 a sectional view through the drive frame and the mast holder from Fig. 8 along the section line DD, Figure 10 a detailed view of detail E of the Fig. 9 , Figure 11 a sectional view through the drive frame and the mast holder from Fig. 8 along section line AA, Figure 12 a detailed view of detail B of the Fig. 11 , Figure 13 a perspective view of the drive frame including the mast holder mounted therein from Fig. 8 from below, as well as Figure 14 the representation from Figure 13 without the right wheel arm.

[0025] Unless otherwise stated, the same reference symbols refer to the same items in the following.

[0026] Figure 1 shows a schematic view of a reach truck with a drive part 100 and a load part 200. The drive part 100 includes, among other things, an electric motor (not shown) and an electric battery (not shown) for driving the reach truck. Furthermore, the drive part 100 includes a drive frame 102 with a base frame 106 and two wheel arms 104, 104' extending from this base frame and running parallel to each other ( Figures 2 to 4). The base frame 106 is preferably a cast frame. To guide the wheel arms 104, 104' when joined to the base frame 106, projections 140 can be provided on the wheel arms 104, 104', which engage in receptacles 141 of the base frame 106 (see in particular Fig. 3 ). The wheel arms 104, 104' each have first guide means 110, 110' designed as guide rails 112, 112' as well as wheel housings 105, 105' arranged at the ends of the wheel arms for accommodating wheels, as shown in particular in the Figures 2 and 3 to recognize.

[0027] The load part 200 comprises a mast 300 and a mast holder 202, wherein forks (not shown) for receiving a load can be arranged on the mast. Furthermore, the mast holder 202 comprises a cross member 206, which connects two parallel side arms 204, 204' (see in particular Figure 5). The mast holder 202 has two mast attachments 209, which extend vertically upwards at the ends of the side arms 204, 204' and are connected to each other by a crosspiece 207. The mast attachments 209 serve to hold the mast 300. Guide rollers 212a, 212b, 212a', 212b' and spacers 114, 114' are arranged on the outer sides of the side arms 204, 204' facing the wheel arms 104, 104', wherein Figure 5 only the guide rollers 212a, 212b and spacers 114 of the right side arm 204 are visible.

[0028] The mast holder 202 is mounted on the first guide means 110, 110' of the wheel arms 104, 104' of the drive frame 102 via the second guide means 210, 210'. As shown in particular in Figure 10As can be seen, the first guide means 110 is formed by a guide rail 112 extending from the inner side 108 of the support arm 104 in the direction of the side arm 204. The second guide means 210 is formed by two guide rollers 212a, 212b, wherein the upper guide roller 212a strikes the guide rail 112 from an upper side, while the lower guide roller 212b engages the guide rail 112 from a lower side. The mast holder 202 is thus held on the guide rail 112 of the support arm 104 via its guide rollers 212a, 212b. The same applies, of course, to the second pair of arms, not shown in detail, consisting of the support arm 104' and the side arm 204'. In addition, Figure 10Spacers 114 arranged on the outer side 208 of the side arm 204 can be seen, which distance the side arm 204 from the guide rail 112 and thus the mast holder 202 from the wheel arms 104, 104'. The mast holder 202 is movably mounted on the drive frame 102 via the guide means 110, 110'.

[0029] The mast holder 202 also has second bearing elements 220, 220' which interact with first bearing elements 120, 120' of the drive frame 102. The first bearing elements 120 of the right wheel arm 104 are particularly Fig. 4 The representation in Fig. 4 shows the right side arm 104 from Fig. 3 in a view rotated about the longitudinal axis by approximately 90°. It can be seen that the first bearing element 120 comprises a running surface 122. Accordingly, the left wheel arm 104' also has a Figures 3 and 4 unrecognizable first bearing element comprising a running surface.

[0030] In Figure 12is shown in detail how the first bearing element 120 and the second bearing element 220 interact with each other, whereby here again only the right arm pair, consisting of the right wheel arm 104 and the right side arm 204, is shown. Attached to an inner side of the side arm 204 is a roller carrier 224 designed as an L-shaped angle piece 228, which extends from the side arm 204 in the direction of the wheel arm 104. At the free end of the L-shaped angle piece 228, a roller 226 is arranged, the axis of rotation RL of which runs perpendicular to the axis of rotation RF of the guide roller 212 and perpendicular to the ground. This forms the second bearing element 220, which, by means of the L-shaped angle piece 228, engages behind the outwardly facing running surface 122 of the first bearing element 120, which faces away from the side arm 204, in such a way that a movement of the wheel arm 104 outwards, i.e. away from the side arm 204, is prevented.A corresponding gripping movement is also exerted on the wheel arm 104' by the second bearing element of the side arm 204', although this is not shown in detail.

[0031] The side arms 204, 204' engage via their second bearing elements 220, 220' into the first bearing elements 120, 120' of the wheel arms 104, 104' in such a way that spreading of the wheel arms 104, 104' outwards away from the side arms is prevented. The second bearing elements 220, 220' are designed to be movable relative to the first bearing elements 120, 120', wherein upon movement of the mast holder 202 along the wheel arms 104, 104', the rollers 226, 226' roll along the running surfaces 122, 122'. This is particularly evident in the Figures 13 and 14 According to the invention, a particularly reliable stabilization of the system consisting of the mast holder and drive frame is achieved, since the side arms always hold the wheel arms together at the point of highest load.

[0032] As also in Figure 12 As can be seen, the bearing elements 120, 220 can be accommodated in a particularly space-saving manner. For example, the running surface 122, along which the roller 226 runs, can be arranged in a recess 230 of the side arm 104. An external bulge 232 of the wheel arm 104 protects the roller 226 from external influences. The same can, of course, also be provided for the bearing elements 120', 220'.

[0033] In Figure 7 It is also evident that the wheel arms 104, 104' are connected to the base frame 106 via connecting regions extending essentially along the y-axis in the direction of the wheel arms. This also counteracts the spreading of the wheel arms 104, 104'. List of reference symbols

[0034] 10Reach truck 100Drive part 102Drive frame 104, 104'Wheel arms 105, 105'Wheel arches 106Base frame 108, 108'Insides of the wheel arms 110, 110'First guide means 112, 112'Guide rails 114, 114'Spacers 120, 120'First bearing elements 122, 122'Running surfaces 130, 130'Connecting areas 140Protrusions 141Receivers 200Load section 202Mast holder 204, 204'Side arms 206Cross member 207Crosspiece 208, 208'Outsides of the side arms 209Mast fastenings 210, 210'Second guide means 212a, 212a'Guide rollers 212b, 212b'Guide rollers 220, 220'Second bearing elements 224, 224'Roller supports 226, 226'Track rollers 228, 228'L-shaped angle pieces 230Notch 232Bump 300Lift mast BBottom RF, RF'Rotation axes of the guide rollers RL, RL'Rotation axes of the track rollers

Claims

1. Reach truck with a drive part (100) and a load part (200), wherein • the drive part (100) comprises a drive frame (102) with two wheel arms (104, 104') extending parallel to one another and a base frame (106) connecting the wheel arms (104, 104') to one another, wherein a first guiding means (110, 110') is arranged on each of the wheel arms (104, 104'), • the load part (200) comprises a mast holder (202) with two side arms (204, 204') extending parallel to one another and a cross beam (206) connecting the side arms (204, 204') to one another, wherein a second guiding means (210, 210') is arranged on each of the side arms (204, 204'), • the side arms (204, 204') of the mast holder (202) extend parallel to the wheel arms (104, 104') of the drive frame (102), so that in each case one of the side arms (204, 204') extends adjacent to one of the wheel arms (104, 104'), • the first guiding means (110, 110') of a wheel arm (104, 104') interacts in each case with the second guiding means (210, 210') of the adjacent side arm (204, 204') in such a way that the mast holder (202) is guided on the wheel arms (104, 104') in a displaceable manner, wherein • a first bearing element (120, 120') is arranged on each of the wheel arms (104, 104') and a second bearing element (220, 220') is arranged on each of the side arms (204, 204'), wherein adjacent wheel arms (104, 104') and side arms (204, 204') are in engagement with one another via their respective bearing elements (120, 120', 220, 220') in such a way that the second bearing elements (220, 220') limit outward movement of the wheel arms (104, 104') away from one another, wherein • the first bearing elements (120, 120') each have an outwardly pointing running surface (122, 122') and the second bearing elements (220, 220') each have at least one running element running along the respectively adjacent running surface (122, 122'), or in that the second bearing elements (220, 220') each have an inwardly pointing running surface and the first bearing elements (120, 120') each have at least one running element running along the respectively adjacent running surface, • wherein the running elements each have a roller carrier (224, 224') that extends in the direction of the adjacent running surface (122, 122') and has at least one roller (226, 226') running along the respective running surface (122, 122'), characterized in that • the roller carriers (224, 224') each comprise at least one L-shaped angle piece (228, 228'), wherein the L-shaped angle piece (228, 228') extends from the respective side arm (204, 204') in the direction of the respective adjacent wheel arm (104, 104') or wherein the L-shaped angle piece (228, 228') extends from the respective wheel arm (104, 104') in the direction of the respective adjacent side arm (204, 204'), wherein the at least one roller (226, 226') is arranged at a free end of the L-shaped angle piece (228, 228').

2. Reach truck according to claim 1, characterized in that the rotation axes (RL, RL') of the rollers (226, 226') extend, during operation of the reach truck (10), perpendicular to a floor (B) supporting the reach truck (10) and parallel to the running surfaces (122, 122').

3. Reach truck according to one of the preceding claims, characterized in that the first guiding means (110, 110') are each arranged on the inner sides (108, 108') of the wheel arms (104, 104') and the second guiding means (210, 210') are each arranged on the outer sides (208, 208') of the side arms (204, 204'), wherein the respective inner side (108, 108') of a wheel arm (104, 104') faces the respective outer side (208, 208') of the adjacent side arm (204, 204').

4. Reach truck according to claim 3, characterized in that the first guiding means (110, 110') each have a guiding rail (112, 112') and the second guiding means (210, 210') each have at least one guiding roller (212a, 212b, 212a', 212b'), wherein the guiding rollers (212a, 212b, 212a', 212b') of the respective second guiding means (210, 210') are each guided on the adjacent guiding rail (112, 112') of the first guiding means (110, 110').

5. Reach truck according to claim 4, characterized in that the rotation axes (RF, RF') of the guiding rollers (212a, 212b, 212a', 212b') run horizontally to a floor (B) supporting the reach truck (10) during operation of the reach truck (10).

6. Reach truck according to claim 1 and claim 5, characterized in that the rotation axes (RF, RF') of the guiding rollers (212a, 212b, 212a', 212b') are arranged perpendicular to the running surfaces (122, 122').

7. Reach truck according to one of the preceding claims, characterized in that spacers (114, 114') are arranged on the inner sides (108, 108') of the wheel arms (104, 104') and / or on the outer sides (208, 208') of the side arms (204, 204').

8. Reach truck according to one of the preceding claims, characterized in that the base frame (106) and the two wheel arms (104, 104') are welded together or that the base frame (106) and the two wheel arms (104, 104') are manufactured together in a casting process or that the base frame (106) is cast and the two side arms (104, 104') are welded to the cast base frame (106).

9. Reach truck according to one of the preceding claims, characterized in that the wheel arms (104, 104') are connected to the base frame (106) via connection areas (130, 130') extending partially along the wheel arms (104, 104').