JP2828779B2 - Telescopic boom - Google Patents

Description

The present invention relates to a telescoping boom comprising at least one external structural member and at least one internal structural member, each of which is designed as a hollow section having an upper flange and a lower flange, The upper flange is
A semi-basket profile with two rounded edges, to which a lower flange is joined by a liner with a substantially U-shaped profile, and each structural member is adjacent at front and rear bearings Attached to the structural member.

Booms of this type are known by convention, for example from mobile cranes. Since the load is suspended on the front end of the elongated internal structural member, the internal structural member with the lower flange is:
A load is applied to the front end of the lower flange of the external structural member.
At the same time, the rear end of the inner structural member applies a load to the upper flange of the outer structural member having the upper flange. Within the scope of the invention, "front" refers to the direction toward the free end of the boom under load, and "rear" refers to the direction toward the end opposite the free end of the boom.

Particular attention must be paid to the construction of the front and rear bearings for the reason that large forces are transmitted. Apart from reliable supports, these bearings must at the same time counteract unwanted deformations of the profile cross section.
Usually, therefore, full support by sliding members on the front and rear bearings is intended. Each of the sliding members is secured to a laterally adjacent flat bearing block on one of the structural members and is supported on an adjacent structural member on the opposite side. The collar-shaped reinforcing support means is required to receive a force acting on the sliding member and the bearing block. Generally, the collar of the internal structural member is made continuous through the cross-sectional shape of the structural member and is integrally formed from the enclosure of the sliding member, while the collar of the front bearing is usually mounted externally on the external structural member. And of a solid material having a dimension of 150 to 300 mm in the longitudinal direction of the boom. The collar thereby reduces the usable extension length of the corresponding structural member. As shown in FIG. 6 (prior art), the internal structural members cannot be fully nested into one another. Since the inner collar prevents this. The same occurs analogously in the region of the front bearing with the outer collar.

DE-OS 1531174 proposes a rolling bearing for a telescopic boom having a polygonal cross section. An outer roll is assigned to each edge of the lower flange and an inner roll is assigned to each edge of the upper flange to accommodate the edge stresses that occur under load. Since the outer and inner rolls impede each other in an inconvenient manner whenever the structural members slide into each other, the available extension length of the structural members is the sum of the diameters of the rolls arranged in parallel. Only at least reduced. Furthermore, the internal roll occupies a considerable space in the hollow profile cross section of the internal structural member, so that the telescopic cylinder unit arranged there has only a small space for extending the boom.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a telescopic boom of the type that is contoured at the start, the beam of which can accept a high level of force, as well as a stable bearing of the structural member and a large usable extension length. Is characterized by:

This object is achieved according to the invention, in which the front bearing has a sliding member only between the lower flanges in the region of curvature and the rear bearing is
Each has a separate flat bearing half liner at the location between the upper flanges only in the region of the rounded edges.

For reasons of such support, the force between two adjacent structural members is transmitted only through a rounded portion that is considerably stiffer than the straight surface of the bearing block, which is standard in the prior art. Thereby, the bulging of the surface portion and the deformation of the profile cross section are prevented. The function of the collar can be quite limited, to the extent that it prevents the structural member from stretching at its ends. The collar can be considerably shorter in the longitudinal direction of the structural member, as it no longer needs to receive the support force to the full extent. In practice, the collar can be reduced to a length of about 50mm. That is, as shown in FIG. 5, the separate structural members can slide into each other to a considerable extent, resulting in a large usable extension length.

On the other hand, the half liners of the sliding members and the flat bearings can be considerably thinner. In the prior art, a thickness of 40-50 mm is still required, but in the solution of the invention the thickness is 20 mm.
mm. That is, in the outer structural member, there is more space for additional internal structural members, thus increasing the usable extension length. With the support according to the invention, the seven structural members can be slid into each other without problems, and the cross-sectional dimensions of the outermost structural members do not exceed the external cross-section of a conventional telescopic boom. Up to 5 previous support according to the prior art
It was only possible to slide the two structural members together.

In addition, the tolerances of the half liners of the sliding members and the flat bearings can be very precisely adapted to the rounded edges and the lower flange shape. Due to this bearing structure, the deformation of the straight section of the cross section is small, while the rounded section ensures that the structural parts are correctly supported on one another. As a result, the added tolerances for compensating for the structural members, which are normally required in the prior art, are eliminated.

The sliding member and the half liner of the flat bearing are advantageously self-centered at the rounded portions. As a result, they need not be fixed in the circumferential direction of their cross section.

In a particularly advantageous embodiment, the rear bearing in the region between the lower flanges consists of at least one linear sliding element extending at least partially on each curved side of the lower flange adjacent to the upper flange. . This configuration is particularly advantageous, for example, when receiving a lateral force that occurs when the mobile crane rotates. The linear sliding member prevents torsion of the boom section.

The rear bearing is composed of two individual sliding block members at a location between the lower edges, each edge of the lower edge being located on each curved side of the lower flange adjacent to the upper flange. For this purpose, the linear sliding element is divided into two individual sliding block elements, each of which receives a torsional force. The support bearing at the lower U-shaped point of the lower flange can be dispensed with. This facilitates the manufacture of the profile section at this location, since it is not necessary to indicate a precise tolerance.

In a variant of the invention, the front bearing consists of a separate flat bearing semi-liner at the location between the upper flanges only in the region of the respective rounded edges. These additional semi-liners of the flat bearing also prevent torsion of the cross section at the rounded edge.

Preferably, the sliding block member of the rear bearing and the half liner of the flat bearing are fixed to the internal structural member.

The sliding member of the front bearing and the semi-liner of the flat bearing can in particular be fixed to an external structural member.

In a preferred embodiment, the radial distance between the inner and outer structural members is greater at the rounded edge site than at the straight section of the upper structural member. As a result, the semi-liner of the flat bearing can be slightly thicker at the rounded edges, so that greater forces can be transmitted. The remaining space in the straight section is minimized in a space-saving manner.

In a possible example, the center points of the outer rounded edges and the center points of the inner rounded edges of the front bearing and / or the rear bearing are arranged in a spaced apart manner and the outer rounded edges The center point of the rounded edge is located closer to the rounded edge than the center point of the inner rounded edge. This increases the space for the semi-liner of the flat bearing in the rounded part, so the distance is
It can be kept small in the adjacent straight section.

Preferably, the semi-liner and / or sliding member of the flat bearing of the rounded edge in the lower flange of the front bearing and / or the rear bearing is in the straight part of the upper flange beyond the curved part. And the semi-liner of the flat bearing and the sliding member are located only on curved parts on said structural member on the side of the structural member to be moved therewith. This limits the support of the flat bearing half-liner and the sliding member on the structural member that moves relatively toward the stable curved portion. This also prevents the structural member from being tightened. This is because the end of the zone (curvature) where the force is introduced does not coincide with the terminal edge of the semi-liner of the flat bearing. On a structural member to which the sliding element is fixed, for example, the sliding element extends in a straight section, so that it is positioned in the circumferential direction at the transition point of the curved section and the straight section, irrespective of the profile cross section.

Advantageously, the semi-liner of the flat bearing in the straight upper flange part and / or the sliding member in the lower flange part on the relatively moving side are spaced from the structural member by an angle α from the straight side. This inclined starting zone prevents the clamping of the structural component in a particularly effective manner.

In a particular embodiment, the outer structural member at the front bearing part comprises a front collar and the inner structural member at the rear bearing part has a rear collar, which are respectively a sliding member, a flat bearing part. Function as a half liner and an axial contact member of the sliding block member. These collars reinforce the profile and prevent bulging or pressing at their ends of the structural member. The sliding members are positioned simultaneously on the collar.

It is recommended that the thickness of the front and rear collars be 1.2 to 2.5 times the thickness of the corresponding boom profile.

In a variant of the invention, the thickness of the upper flange is different from the thickness of the lower flange.

In a particular embodiment, the lower flange U-shaped liner comprises two spaced rounded liners;
The liners are interconnected by a straight web located therebetween. This special profile cross-section of the U-shape shows a great resistance to bending, so that it is turned outwards as particularly suitable. According to the invention, the lateral force is also introduced into the curved zone of the profile, i.e. through the rounded liner, into the lower flange, so that the liner effect of the curved part has a very high resistance to clamping. . Thereby, the film effect of the liner is utilized.

Preferably the web length relative to the profile width is
Almost corresponds to a ratio of 1: 3. The straight side distance between the upper and lower flanges of the structural member must be considered here as the profile width.

The front bearing consists of a separate sliding member at the location between the lower flanges at the location of the respective rounded liner. The force is also transmitted solely through the rounded part in the lower flange area of the front bearing. Width tolerances of the individual structural members can be compensated for appropriately by separate, separate arrangements of the sliding members. Furthermore, there is no moment at the transition site, on the straight side of the upper flange or on the straight web, since circumferential tension is introduced tangentially.

Advantageously, at the site of the rounded liner,
The radial distance between the inner and outer structural members is greater than in the straight section of the lower flange.

In a preferred embodiment, the center point of the outer rounded liner of the front bearing and the center point of the inner rounded liner are spaced apart from each other, and the center point of the outer rounded liner is , Placed closer to the rounded liner than the center point of the inner rounded liner.

The ratio of the width of the profile to the height of the profile is about 1: 1.15 to 1: 1.4.

The ratio of the length of the straight side between the rounded edge of the upper flange and the subsequent curved part of the lower flange to the height of the profile is in particular from 1: 1.6 to 1: 2.

The present invention will now be described in detail with reference to examples and drawings.

FIG. 1 is a simplified and partially cross-sectional view of a portion of an external structural member that partially receives an internal structural member.

 FIG. 2 is a sectional view taken along line AA of FIG.

 FIG. 3 is a sectional view taken along line BB of FIG.

FIG. 4 is an enlarged partial cross-sectional view taken along line BB of FIG. 1 with a sliding member at the rounded edge portion.

FIG. 5 is a simplified cross-sectional view of the rear end of the three telescoping structural members of the boom of the present invention.

FIG. 6 is a simplified cross-sectional view of three telescoping members having a wide rear collar of a boom according to the prior art.

FIG. 7 is a cross-sectional view through the front bearing of a boom of the present invention having eight structural members, the lower flange of which has two spaced rounded liners.

The outer structural member 14 and the inner structural member 16 are shown in each of FIGS. The internal structural member 16 is an external structural member.
It is positioned inside the front part of 14 over part of its length. Each structural member consists of two bent sheet half liners, which are connected to one another by longitudinal welding. The upper flange 1 of each structural member has a U-shape provided with a rounded edge R in the shape of a quadrant. In FIGS. 2 and 3, the two rounded edges of the inner structural member 16 are designated Ri, and the two rounded corners of the outer structural member 14 are designated Ra. 60 rounded edges
Extends from ゜ to 90 ゜.

The lower flange 2 of the two structural members 14 and 16 has a semicircular shape with a radius equal to half the width (b) of the corresponding upper flange. The radius of the lower flange 2 of the inner structural member 16 is larger than the radius of the lower flange of the outer structural member 14.
It goes without saying that it is correspondingly small. The upper and lower flanges can be of different thicknesses.

The upper and lower flanges which are welded together have, on the longitudinal side, a front collar 7 at the end and a rear collar 8 at the rear end in the form of a plate welded thereto. These collars are made corrosion resistant and function as bearings. Each lower flange 2 is assigned a front bearing 3 and each upper flange 1 is a rear flange 4
Is assigned.

The two collars 7 and 8 simultaneously form a stop for the plastic sliding member 10 and the half-liner 12 of the flat bearing, which are provided at least in the area of the bearing between the inner and outer structural members. The sliding member 10 made of plastic, preferably polyamide, has a shape which corresponds to the semicircle of the space between the lower flange of the inner structural member 16 and the lower flange of the outer structural member 14 and is assigned to each bearing assigned to the lower flange. 3 are provided. Furthermore, at the location of each bearing 4 assigned to the upper flange 1, a semi-liner 12 of a supporting flat bearing, as shown in FIG.
At least two spaces are provided between the inner upper flange and the outer upper flange at the two rounded edges Ri and Ra. The semi-circular sliding member 10 advantageously extends to a horizontal line indicated by C in FIGS.

The sliding member 10 and the semi-liner 12 of the flat bearing are fixed to the outer structural member 14, respectively.

The cooperation of the two bearings 3 and 4 allows lateral forces and bending moments to be transmitted from the internal structural member to the adjacent external structural member.

As shown in FIG. 1, if a force F acts on the internal structural member 16, that force produces a moment M, which in turn produces lateral forces Qv and Qh. The lateral force Qv deforms the lower flange of the internal structural member into an oval shape. The lateral force Qv is introduced into the outer structural member 14 through the sliding member 10, so that its cross-section is similarly transformed into an oval shape. In particular, its cross section becomes longer in the vertical direction and shorter in the horizontal direction. It is this lateral shortening that results in the advantageous stabilization of the bearing 3 as a Fassdauge effect as a result of the pressure on the internal structural members.
In addition, tightening is prevented by the large surface contact caused by the sliding member 10. Furthermore, undesired tightening is prevented by the lateral force Qv acting on the semicircular lower flange, so that the membrane effect of the liner can be used.
As a result, the plate thickness can be reduced, and the own weight is reduced.

The rear bearing force Qh exerts a stress on the inner surface of the outer structural member 14 at the location of the rear bearing 4. As shown in FIG. 3, the two inner rounded edges Ri are connected to the rear bearing 4
At the point of connection, with the help of two flat bearing half liners 12, connected to two external rounded edges Ra, the internal rounded edges of which belong to the internal structural member 16,
The outer rounded edge also belongs to the outer structural member. Regarding this rear bearing 4, the semi-liner of the flat bearing
It should be noted that 12 is not supported by a separate collar as in the prior art, but is supported by an arched plate of internal structural member 16. At the same time, the disk effect of the flange is exploited when a load is introduced. Next, in the telescopic boom of the present invention, the semi-liner of the flat bearing portion is used.
This has the effect that the width of the sliding member 10 (i.e., the dimension in the longitudinal direction of the boom) depends on the width of the associated collar 8. As already mentioned, such a structure also increases the usable boom length.

The thickness of the front collar 7 and the thickness of the rear collar 8 are preferably 1.2 to 2.5 times the thickness of the plate used for the corresponding boom profile.

As shown in FIG. 2, the plastic flat bearing half liner 18 has a front collar 7 in the space between the outer rounded edge Ra and the inner rounded edge Ri.
Can be assigned to each. Instead of the two flat bearing half liners 18 shown in FIG. 2, only a single sliding member can be provided. The flat bearing half liner 18 must be designed and arranged to prevent the internal structural member 16 from tilting inward of the external structural member 14.

The bearing assigned to the flat bearing half liner 18 is not permanently acted upon by force.

As shown in FIG. 3, a sliding block member 15 made of plastic can be provided at the rear collar 8, that is, at the lower flange thereof. These sliding block members 15 are arranged between the semicircular lower flange of the inner structural member 16 and the semicircular lower flange of the outer structural member 14. They advantageously extend at their lower ends to a horizontal line c. Instead of the two-part configuration of the sliding block member 15 as shown in FIG. 3, the structural member can also be a one-piece configuration. Generally sliding block member 15
Must be designed and arranged such that the internal structural member 16 does not tilt inward of the external structural member 14. I mean,
This is because the above-mentioned sliding member is specifically subjected to stress when a lateral force, that is, a component of the transverse force acts on the internal structural member.

The flat liner half liner 18 (FIG. 2) described above only has a minimum clamping of the internal structure in order to support the internal structure only in its maximum extended state, i. Loaded only in length.

FIG. 4 shows the semi-liner 12 of the flat bearing between the two rounded edges Ri and Ra of the upper flange 1 at the rear end of the internal structural member 16. At the rounded edges Ri, Ra, the distance between the two upper flanges 1 is greater than the distance in the straight part of the upper flange 1. The rounded edges Ri, Ra have central points Ma, Mi spaced apart from each other,
The center point Ma of the rounded edge Ra is the half liner of the flat bearing
It is located close to 12 and rounded edges Ri, Ra respectively. In this figure, the center point Ma has two drawn radii ra
Each is represented by, and the center point Mi is similarly represented by two radii ri.

Since the semi-liner 12 of the flat bearing is fixed to the inner structural member 16, it moves relatively with respect to the rounded edge Ra of the outer structural member. The flat bearing half liner 12 extends into a straight section adjacent to the rounded edges Ri, Ri and rests on the internal structural member 16 in the straight section. With respect to the outer structural member 14, the flat bearing half-liner 12 is retracted at an angle α from the outer structural member 14 starting from the transition point to a straight section. For this reason, it is placed only at the site of the rounded edge Ra on the external structural member 14. By analogy in FIG. 4, a semi-liner 18 of a flat bearing at the front end is formed. The semi-liner 18 of the flat bearing also rests on the outer structural member 14 in the straight section and retracts in the straight section of the inner structural member 16 at an angle α from the upper flange of the inner structural member 16.

FIG. 5 illustrates a telescopic beam having three structural members. In a vertical section, a sectional view of the rear flat bearing half liner 12 is shown. This liner is placed on the small rear collar 8 at one end and is bordered by an edge 20 at the other end. The edge 20 is peripherally confined to the portion of the semi-liner 12 of the flat bearing. In the nested state shown, the half liners 12 of the flat bearings of the adjacent structural members can overlap each other to a considerable extent because they overlap.

FIG. 6 illustrates the three structural members in a retracted state according to a prior art bearing arrangement. These structural members are supported here inwardly by a rounded perimeter, each bearing member 30 being a semi-basket bearing block 31 which is biased inward with respect to the corresponding structural member.
Accepted by. The boundaries of the bearing blocks 31 are each formed by two collars 32 that continuously traverse the cross section of the structural member.

As shown in FIG. 6, the continuous collar 32, which requires stability, prevents the internal structural member 16 from being further inserted, so that the rear ends of the internal structural members 16 need to be arranged in parallel. is there. As further shown, the bearing member 30 is significantly thicker in the radial direction than the sliding member 12 (FIG. 5) according to the invention.

In FIG. 7, a telescoping boom according to the invention having eight structural members is shown, wherein the U-shaped liner of each lower flange 2 is formed from two spaced round liners 33 having the shape of a quadrant. Straight web 34 extending parallel to the straight part of the upper flange 1 between the rounded edges Ri, Ra
Are located between the rounded liners 33.

Sliding members 10 having a substantially quadrant shape are each disposed between the rounded liners 33 of two adjacent structural members. The sliding members 10 are each adapted to the shape of the rounded part of the rounded liner 33. Sliding member
Each 10 is fixed to its external structural member 14 and between the lower flange 2 and the upper flange 1 a straight web 34
And in the straight side part 35, respectively, partially external structural members
Extends on the 14 side. On the side of the internal structure 16 the sliding member 10 is placed only on the curved part of the rounded liner 33. In the straight section, the sliding member 10 is formed analogously to the end of the half liner 12 of the flat bearing shown in FIG. Starting with the rounded part,
At an angle α from the internal structural member on the side of the internal structural member 16 in the oblique taper zone. Of course, the rear bearing 4 can also be formed on the lower flange part 2, as shown in FIG. In this case, the sliding block member 15 is formed as a rounded liner 33.

In the cross-section illustrated in FIG. 7, it goes without saying that, as in the embodiments illustrated in the other figures, the same arrangement of the half liners 18 of the flat bearings can be selected at the locations of the rounded edges Ri, Ra. No.

──────────────────────────────────────────────────続 き Continued on front page (58) Field surveyed (Int.Cl. ⁶ , DB name) B66C 23/00-23/94

Claims (20)

(57) [Claims] 1. A telescopic boom comprising at least one external structural member (14) and at least one internal structural member (16), each of which is an upper flange (1) and a lower flange (2). The upper flange (1) has a half-basket profile provided with two rounded edges (Ri, Ra) to which the lower flange (2) is substantially U-shaped. Joined by a liner with a V-shaped profile, and each structural member is
In a boom which is attached to adjacent structural members at front and rear bearings (3, 4), said front bearing (3)
Has a sliding member (10) only in the area of curvature between the lower flanges (2) and the rear bearings (4) are each provided with a rounded edge (Ri, Ra). Telescopic boom, characterized in that it has a separate flat bearing half-liner (12) only in the area between said upper flanges (1). 2. In a portion between the lower flanges (2), the rear bearing (4) is connected to the upper flange (1).
Boom according to claim 1, characterized in that it has at least one linearly shaped sliding member (15) extending at least partially on each curved side of the lower flange (2) adjacent to the lower flange. 3. The rear bearing (4) comprises two separate sliding block members (15) at a location between the lower flanges (2), one of the sliding block members being the upper flange. Boom according to claim 1 or 2, characterized in that each boom is arranged on a respective curved side of the lower flange (2) adjacent to (1). 4. The front bearing (3) in the area between the upper flanges (1) is a semi-liner of a separate flat bearing only in the region of the respective rounded edge (Ri, Ra). The boom according to any one of claims 1 to 3, wherein the boom comprises (18). 5. The sliding block (15) of the rear bearing (4) and the half liner (12) of the flat bearing are fixed to the internal structural member (16). The boom according to any one of claims 1 to 4. 6. The sliding member (1) of the front bearing (3).
Boom according to one of the preceding claims, characterized in that the half liner (0) and the flat bearing part (18) are fixed to the external structural member (14). 7. The radial distance between the inner and outer structural members (14, 16) is greater at the rounded edges (Ri, Ra) than at the straight portion of the upper flange (1). The boom according to any one of claims 1 to 6, wherein the boom is also large. 8. A center point (Ma) of said outer rounded edge (Ra) of said front bearing (3) and / or said rear bearing (4), and said inner rounded. Edge (Ri)
Center points (Mi) are spaced apart from each other, and the center point (Ma) of the outer rounded edge (Ra) is the center point (Mi) of the inner rounded edge (Ri). 8. The boom according to claim 1, wherein the boom is arranged closer to the rounded edge (Ri, Ra) than to the boom. 9. A semi-liner of said flat bearing of said rounded edge (Ri, Ra) at said lower flange portion (2) of said front bearing and / or rear bearing (3, 4). (12, 18) and / or the sliding member (10, 15)
Extends beyond the curved section into the straight section, and the semi-liner (12,
A boom according to any one of the preceding claims, characterized in that (18) is adjacent to the structural member only on curved parts on the side of the structural member to be moved therewith. 10. The flat bearing half liners (12, 18) on the straight upper flange part (1) and / or the sliding members (10, 15) on the lower flange part (2).
The boom according to claim 9, wherein the boom is spaced apart from the structural member at an angle (α) from the straight side on a relative movement side. 11. The external structural member (16) at the location of the front bearing (3) has a front collar (7) and the internal structural member (7) at the location of the rear bearing (4). 14) has a rear collar (8), said collar serving as an axial abutment for the sliding member (10), the flat liner half liners (12, 18), and the sliding block member (15). The boom according to any one of claims 1 to 10, wherein: 12. The method according to claim 1, wherein the thickness of the front and rear collars is 1.2 to 2.5 times the thickness of the corresponding boom profile.
Boom according to the section. 13. The boom as claimed in claim 1, wherein the thickness of the upper flange is different from the thickness of the lower flange. 14. The U-shaped liner of said lower flange (2) comprises two spaced rounded liners (33) interconnected by a straight web (34) disposed therebetween. 2. The method according to claim 1, wherein
14. The boom according to any one of claims 13 to 13. 15. The boom according to claim 14, wherein the length of the web relative to the width of the profile substantially corresponds to a ratio of 1: 3. 16. The front bearing (3) at the location between the lower flanges (2) has a separate sliding member (10) at the location of the respective rounded liner (33). The boom according to claim 14 or claim 15, wherein 17. At the location of the rounded liner (33), the radial distance between the inner and outer structural members (14, 16) is greater than in the straight section of the lower flange (2). Claim 14 to 16 characterized by being large
The boom according to any one of the preceding claims. 18. The center of the outer rounded liner (33) of the front bearing (3) and the center of the inner rounded liner (33) are spaced apart from each other; Also, the center point of the outer rounded liner (33) is located closer to the rounded liner (33) than the center point of the inner rounded liner (33). A boom according to any one of claims 14 to 17, characterized in that: 19. The boom according to claim 1, wherein the ratio of the width of the profile to the height of the profile is about 1: 1.15 to 1: 1.4. 20. The straight side (35) between the rounded edges (Ri, Ra) of the upper flange (1) and the adjacent curved portion (33) of the lower flange (2). Of length,
20. A boom according to any one of the preceding claims, wherein the ratio of profile to height is between about 1: 1.6 and 1: 2.