DE29608097U1 - Lifting device for manhole frames of rainwater inlets - Google Patents

Description

JOCH-OIgDE
06 May 1996

DESCRIPTION

Lifting device for manhole frames of rainwater inlets

TECHNICAL AREA

The invention relates to a device for lifting manhole frames that are installed in road surfaces. The manhole frames are part of rainwater inlets. These rainwater inlets are located on the lateral edges of road surfaces, usually bordered by curbs.

When repairing the upper road surface, it is often necessary to adjust the level of the tops of the rainwater inlets to the new road surface. In this context, the upper shaft frame of the rainwater inlet channel, made of gray cast iron and concrete composite material, must be raised. The shaft frame, which is placed on the shaft of the rainwater inlet in cement mortar and partially encased in concrete, is very firmly connected to the shaft substructure, so that the tensile forces required to tear it away from the shaft must be very high.

STATE OF THE ART

A motor-driven, hydraulically operated manhole frame lifter is known for lifting manhole frames in sewage inspection shafts and hydrant shafts. These shafts are located in the middle area and not in the side area of streets. This means that the shaft is freely accessible from all sides of the street and is not limited by raised curbs. A manhole frame lifter can therefore be used to lift the manhole frames of such manholes located in the middle area of the street.

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the one that has a ring-shaped base frame as a support frame. The base frame has such a diameter that it can be placed on the road surface in the immediate outer area of the shaft frame. The base frame and thus the entire shaft frame lifter can be moved using wheels and its height can be adjusted hydraulically relative to the wheels. Articulated pull rods that can be moved upwards hydraulically are attached to the support frame. Several chisels are attached to the lower end of the pull rods, which can be hydraulically adjusted laterally outwards so that the chisels can be pressed into the concrete joint below a shaft frame. By raising the pull rods, the chisels, which press against the underside of the shaft frame, tear the shaft frame off the shaft substructure so that the shaft frame can be moved upwards to the new level corresponding to the new top of the road surface.

Such manhole frame lifters cannot be used to lift manhole frames that are installed in rainwater inlets. The base frame of the manhole frame lifter cannot be placed flat on the road surface surrounding the manhole; the curbs mean that the area around the rainwater inlet has a height difference. The base frame is also not suitable for the regularly rectangular or square lateral rainwater inlets due to its ring-shaped contour. In addition, the clear space required to insert the pull rods inside a manhole frame in rainwater inlets can be very small, so that the previously known manhole frame lifters with their chisel device attached to pull rods cannot be used.

JOCH-OIgDE
06 May 1996

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DESCRIPTION OF THE INVENTION

Based on this state of the art, the invention is based on the object of specifying a lifting device of the type mentioned at the beginning, with which the shaft frames of rainwater inlets on the side of the road can also be lifted in a comparably favorable manner as is the case with the shaft frames of wastewater inspection shafts.

This invention is given by the features of the main claim. The invention is therefore characterized in that a lifting device comparable to the prior art is used in conjunction with an essentially rectangular, U-shaped additional frame that can be quickly and detachably attached to the base frame from below. The interior of this additional frame is somewhat larger than the external clearance profile of the shaft frame of rainwater inlets on the side of the road. To lift the shaft frame, the base frame is no longer placed directly on the road surface, but an additional frame is positioned between the road surface and the base frame. This additional frame can be attached to the base frame using quickly detachable fastening devices.

The manhole frame lifter according to the invention can be moved from one rainwater inlet to another rainwater inlet with an additional frame attached to it. If an inspection manhole or other manhole in the middle of the street is to be "serviced", the additional frame can be quickly and easily detached from the base frame, so that a manhole frame lifter without an additional frame can then be used in a similar way to that known in the art for lifting the manhole frame of an inspection manhole. Details of the design of this additional frame and its attachment to the base frame of the manhole frame

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Lifters are the subject of subclaims and are also described in more detail in embodiments.

Due to the different design of existing rainwater inlets and thus also the different shaft frames, it is also extremely advantageous within the scope of the invention to design the chisel device, which is attached to the pendulum-suspended pull rods of the shaft frame lifter, so that it can be quickly replaced. In this way, the "correct" chisel device required for the specific rainwater inlet can be attached to the shaft frame lifter. The chisel device itself is also designed differently, since it must be able to penetrate very small clearance profiles. Nevertheless, the chisel device must be designed to have a very high lifting capacity, since the pressure forces required for the lateral movement of the chisels, with which the chisels must penetrate into the concreted joint below the shaft frame, can be very large.

More detailed embodiments of various chisel devices according to the invention are the subject of further subclaims and are the subject of embodiments shown in the drawing.

Further features and advantages of the invention can be found in the features further specified in the subclaims and in the following embodiments.

BRIEF DESCRIPTION OF DRAWING 30

The invention is described and explained in more detail below using the embodiments shown in the drawing. They show:

JOCH-OIgDE
06 May 1996

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Fig. 1 is a perspective exploded view of a shaft frame lifter with the additional frame detached from it, next to a water inlet bordered by a curb on one side of the road,

Fig. 2 is a side view of the additional frame of Fig. 1, Fig. 3 is a plan view of the additional frame of Fig. 2,

Fig. 4 is a partially sectioned side view of a first chisel device according to the invention attached to the shaft frame lifter,

Fig. 5 is a plan view of the chisel device according to Fig.

Fig. 6 is a side view of a second chisel device according to the invention,

Fig. 7 is a side view of a third chisel device according to the invention.

WAYS TO CARRY OUT THE INVENTION

A shaft frame lifter 10 has a support frame in the form of a ring-shaped base frame 12. The base frame 12 is attached to two chassis 16, 18, each of which has two wheels, which are attached to it opposite one another. The two chassis 16, 18 can be extended using a working cylinder 20, which can be extended hydraulically, and the base frame 12 can be moved away from the contact surface for the wheels 14, which is, for example, the road surface 21. By operating a control slide, the base frame 12 is lowered downwards as a result of the double-acting hydraulic cylinders.

06 May 1996

Four pairs of pull rods 22, 24, 26, 28 are held on the base frame 12. Each pair of these pull rods is pivotably mounted back and forth by means of an upper pivot shaft 30. A working cylinder 32 is positioned between each two pull rods of a pull rod pair 22, 24, 26, 28. By extending the piston rod 34 of each working cylinder, the pull rod pairs 22, 24, 26, 28 can be moved upwards or lowered together.

A chisel device 40 is mounted on the underside of the four pull rod pairs 22, 24, 26, 28 in this case, as will be described in more detail below. The chisel device 40 contains chisels that can be moved outwards to the side. The pull rod pairs 22, 24, 26, 28 can be pivoted outwards with their lower ends for this purpose. The working cylinders of this chisel device 40 are also operated hydraulically. All working cylinders of the chisel device 40 are supplied with hydraulic oil at the same time.

The hydraulic pressure is generated by a petrol engine 42, in this case, to which a hydraulic pump is flanged. The hydraulic oil is sucked out of a reservoir 44 by the hydraulic pump and returned to the reservoir 44 via a return line. This hydraulic supply of a shaft frame lifter 10 is basically known.

To position the shaft frame lifter 10 in the area of a rainwater inlet 50, it is moved to the rainwater inlet 50 by means of manual adjustment via a drawbar 52. The shaft frame lifter 10 rolls on its wheels 14.

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06 May 1996

An additional frame 54 can be attached to the base frame 12 from below in a quick and easy manner. Conversely, the additional frame 54 can also be quickly removed from the base frame 12.

The additional frame 54 has three rectangular tubes 56, 58, 60, which are attached to one another in the shape of a U. On the U-profile thus created, further end areas 62, 64 are attached to the free ends of the opposite rectangular tubes 56, 60, which correspond in cross-section to the rectangular tubes 56, 60. The outer surfaces of the end areas 62, 64 are flush with one another, so that these end areas 62, 64 and thus the entire additional frame 54 can be positioned flat on the inner side surface 66 of curbs 68. The curbs 68 directly border the rainwater inlet 50, which is located lower in the road surface 21.

A rod-shaped holding member 70, 72 is fastened in each of the two end regions 62, 64 of the additional frame 54. These two holding members have a gap-like distance 74 from the surface of the end region 62 or 64. This distance 74 is such that the lower flange 76 of the base frame 12 fits between them. In addition, the top of the holding members 70, 72 is so far away from the surface of the end regions 62, 64 that the holding members 70, 72 can be pushed into the U-shaped interior of the base frame 12 from the outside.

To attach the additional frame 54 to the base frame 12, the base frame 12 is pushed over the additional frame 54 from the bottom left in Fig. 1. The base frame 12 slides with its lower flange 76 into the gap-like distance 74. In this way, the rear area of the additional frame 54 in Fig. 1 is positioned sufficiently firmly on the base frame.

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The correct position of the additional frame 54 on the base frame is further improved by two adjusting screws 80, 82, which each pass through a hole with an internal thread arranged in the bent collar end 84 of the holding member 70, 72.

The front area of the additional frame 54 is thus attached to the base frame 12 in the following manner.

On the outside of the middle rectangular tube 58, a swivel plate 86 is mounted so that it can swivel up and down about a swivel axis 88 that runs parallel to the extension of the additional frame 54 and also of the base frame 12. Two spring latches 90, 92 are fastened in the opposite lateral end areas of this swivel plate 86 so that they can grip behind a plate 94 on the outside of the base frame 12 when the swivel plate 86 is folded up, as shown in the drawings (Fig. 3). The latches 90, 92 hold the swivel plate 86 in its raised position on the base frame 12 by their rear contact with the plate 94. The swivel plate 86 can be fixed immovably to the swivel plate 86 using an expansion screw 98 with a toggle handle 96. The plate 94 is then held firmly clamped between the swivel plate 86 or the one with the expansion screw 98 passing through it and the two latches 90, 92 that laterally surround the plate 94 from the rear. In this way, the additional frame 54 is also firmly but detachably attached to the base frame 12, including in its front area, via the swivel plate 86. By folding over the levers 100 on the end sides of the latches 90, 92, the two latches 90 can be moved laterally outwards from their rear contact with the plate 94 along their latch axis 102, the swivel plate 86 can be folded downwards away from the base frame 12 and then the base frame 12 can be detached from the additional frame 54 - in Fig. 1

JOCH-OIgDE
06 May 1996

bottom left - move away. In this way, the base frame 12 and the additional frame can be easily and quickly attached to one another and also detached from one another again.

In use, the additional frame 54 is positioned above the rainwater inlet 50 so that its interior, which is enclosed by the rectangular tubes 56, 58, 60, can frame the rainwater inlet 50. The chisel device 40 or another chisel device can then be lowered into the rainwater inlet 50 through the opening 110 released after the rainwater inlet cover 108 has been moved away in order to pull up the shaft frame present there.

The shaft frame lifter 10 shown in Fig. 4 and 5 has a chisel device 40.2 which has only a single working cylinder 112. A piston 114 can be adjusted hydraulically in the cylinder 112. The cylinder 112 is fastened with its bottom surface to a transverse sleeve 116. Another transverse sleeve 118 is fastened to the front side of a piston rod 120. A bolt 121, 122 engages in each of the two sleeves 116, 118 and can be rotated axially in the sleeve 116 or 118. The bolt 121 or 122 is fastened to front plates 124 _and 126 which close off the front side of a U-shaped transversely aligned profile 128 or 130. The left profile 128 is fastened to a left rigid hanging member 132. In the same way, the right profile 130 is attached to a right hanging link 134. The left hanging link 132 is attached to an articulated bearing point 133 of a left tie rod pair 26 and the right hanging link 134 is attached to an articulated bearing point 135 of a right tie rod pair 28. The two bearing points 133, 135 are connected to one another by a spreading link 138, so that the mutual horizontal distance between the two bearing points 133, 135 and thus the tie rod pairs 26, 28 is constantly large at this point.

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A chisel 140, 142 is attached to each of the two U-shaped profiles 128, 130 in a cantilevered manner.

A tension spring is attached to the two end plates 124 and 126, which are located at the ends of the U-shaped profiles 128 and 130, as seen from above (Fig. 5) - on each side next to the working cylinder 112. These two tension springs 146, 148 pull the two profiles 128, 130 and thus the two chisels 140, 142 towards each other. In the extremely contracted state, the chisel device 4 0.2 can be moved through the narrowest interior area of a shaft frame 150, which in this case is L-shaped, from top to bottom or vice versa from bottom to top. Below the base 152 of the shaft frame 150, the chisels 140, 142 are moved laterally outwards - Fig. 4 and 5. This is done against the force of the tension springs 146, 148 by extending the piston rod 120. The sleeve 118 attached to the piston rod 120 and the opposite sleeve 116 attached to the bottom of the cylinder 112 move away from each other. This also causes the bolts 121 and 122 in the sleeves to move laterally away from each other. The profiles 128, 130 and thus also the chisels 140, 142 move away from each other via the bolts 121, 122 positioned in the sleeves 116, 118. In this way, the chisels 140, 142 can be positioned below the shaft frame 150. By relieving the load on the working cylinder 112, the chisels 140, 142 are moved towards each other again by the spring force of the two springs 146, 148. However, it is also possible to provide working cylinders that can be loaded twice, provided that the available space inside a shaft frame allows this. The provision of tension springs could then be dispensed with.

In the state shown in Fig. 5, in which the chisels 140, 142 are in flat contact with the base 151 of the shaft frame 150 from below, the shaft frame as a whole can be

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Pulling up the pairs of pull rods 26, 28, as already described at the beginning in connection with Fig. 1, can be moved upwards. ■

The chisel device 40.2 shown in Fig. 4 and 5 allows a very small construction between the chisels 140, 142, so that the chisel device 40.2 is suitable for very small rainwater inlets, such as for so-called Elcord/longitudinal record street drains. This chisel device 40.2 is connected to the pull rod pairs 26, 28 via the quick-release fasteners in the bearing points 133, 135. These are bolt-like links that reach through existing drill holes in the hanging links 132, 134 and the pull rod pairs 26, 28.

In the chisel device 40.4 shown in Fig. 6, all four pairs of tie rods 22, 24, 26, 28 are used, of which pair 22 cannot be seen in Fig. 6. In the lower areas of these pairs of tie rods, bearing points 133, 135 are formed opposite one another. The two expansion members 138.1 and 138.2 in between are arranged crosswise and connected to one another at their common crossing point by a screw connection 151. In this way, the lower areas of the four pairs of tie rods are arranged at a fixed distance from one another. In contrast to the chisel device 40.2 (Fig. 4 and 5), the chisel device 40.4 has four hanging members 132, 134, corresponding to the four pairs of tie rods 22 to 28.

At the lower ends of the hanging links 132, 134, four working cylinders 153 are arranged in a star shape with their bottoms firmly attached to one another. A common central hydraulic supply line 156, indicated by a dot-dash line, leads into the four cylinders.

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06 May 1996 &idiag;&Igr; .* · · &idgr; ***· · "»···* ·

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A piston rod 160 having a central opening 158 is movably guided in each of the four cylinders 153. A guide pin 162 engages with its conical rear side in the front opening 158 of each piston rod 160. The guide pin 162 is screwed into a chisel 140 or 142 with its other end. The guide pin 162 is shaped in such a way that the piston rod 160 presses against the chisel 140.

The chisel 140 or 142 is firmly attached to the hanging link 132, 134. The pivoting movement of the chisel 140 or 142 relative to the working cylinder 153 when the hanging links 132, 134 are pivoted is made possible by the conical back of the guide bolt 162.

Above the four lifting cylinders 153 there are tension springs 146 which, like the lifting cylinders 153, are arranged in a star shape. The tension springs are firmly attached to opposite hanging links 132, 134, to the lugs 161 located there. These working cylinders 153 are also only hydraulically actuated in such a way that their piston rods 160 are moved laterally outwards. When the pressure in the lifting cylinders 153 is released, the chisels 140, 142 move back to their retracted position, which is caused by the tensile force of the springs 146.

Due to its compact design, such a chisel device 40.4 is suitable for shaft frames with a minimum internal diameter of 350 mm.

A chisel device 40.6 for shaft frames 150.6 with a minimum inner diameter of 450 mm is shown schematically in Fig. 7.

In contrast to the chisel device 40.4 shown in Fig. 6, the chisel device 40.6 is also connected to four pull

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rod pairs 22, 24, 2β, 28 are rigidly attached. For this purpose, their hanging links 132.6, 134.6 are bolted to two bearing points 133, 133.2 of each tie rod pair using quick-release fasteners.

In the lower areas of the four hanging links 132.6 there is a bolt 121 or 122, similar to the chisel device 40.2 (Fig. 5). The bolt 121, 122 engages in a sleeve 116 or 118. The sleeve is firmly attached to the front side of a piston rod 120.6. In addition, a chisel 140, 142 is attached to a hanging link 132.6, 134.6.

The piston rod 120.6 is held in a working cylinder 164 so that it can be displaced longitudinally and can be moved outwards by applying hydraulic pressure to a piston 114.6. Here, too, there is a common hydraulic supply line 156 for all four working cylinders 164, which are arranged in a star shape as in the illustration according to Fig. 6.

Above the four star-shaped working cylinders 164, tension springs 14 6 are arranged in a star shape. These are attached with their outer ends to a tab 170 projecting upwards on the respective bolt 121, 122.

The movement of the chisels 140, 142 towards each other is effected by the tensile force of the springs 146, while the movement away from each other of the two opposing chisels is effected by the corresponding extension of the piston rods 120.6.

In the state shown in Fig. 7, shaft frames 150.6 with a minimum inner diameter of approximately 450 mm can be moved upwards by moving the four tie rod pairs 22 to 28 upwards.

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The respective chisel devices 40.2, 40.4, 40.6 are exchanged via bearing points 133 and 133.2, which are present at the lower ends of the pull rod pairs 22 to 28. While in the chisel device 40.6 (Fig. 7) both bearing points 133, 133.2 of each pull rod pair 22 to 28 are used, in the chisel device 40.4 (Fig. 6) only the lower bearing point of each pull rod pair 22 to 28 is used. In the chisel device 40.2, only one bearing point of a tie rod pair is also used, but only with two opposing tie rod pairs 26, 28. In addition, in the chisel devices 40.2 and 40.4, the bearing points are fixed in their mutual distance by a spreading element or two spreading elements.

The lifting device according to the invention is particularly characterized by the fact that it can be used for all common rainwater inlets. The "correct" chisel devices can be quickly and easily attached without tools or replaced with the chisel device already present.

In the case of the chisel devices 40.4 and 40.6 shown in Fig. 6 and 7, which are used for round shaft frames with a diameter of 350 mm and 450 mm, it is advantageous that the chisel device engages the shaft frame from below at four points distributed around the circumference. These four lifting points are located centrally on the corresponding long and short sides of the rainwater inlet (see Fig. 1). The chisel devices according to the invention engage - based on the representation in Fig. 1 - at points A, while devices in the prior art only engage at three points, at points B (Fig. 1). Round shaft frames, especially those with a diameter of 350 mm, have their weakest points at the corner points B.

At these corner points, the frames break easily, with the result that the no longer functional shaft frames

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must be replaced by new shaft frames. With the lifting device according to the invention, the risk of damage to the shaft frame is practically eliminated. This is of particular economic importance, apart from the fact that the device according to the invention can be used universally thanks to easy conversion/addition.

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Claims (1)

JOCH-OIgDE J ; · ... . ..*' 02 May 1996 III · · · "*· · '..ll" _i_
EXPECTATIONS 01) Device for lifting shaft frames built into road surfaces from existing rainwater inlets on the sides of the road, marked by - a motor-driven, hydraulically operated shaft frame lifter (10), --which is intended for sewage inspection shafts and hydrant shafts located in the middle of streets , - which has a ring-shaped base frame (12) as a supporting structure, -- which can be moved by means of wheels (14) and is hydraulically adjustable in height relative to the wheels, -- which has articulated, hydraulically upwardly movable drawbars (22, 24, 26, 28), -- which has a chisel device (40) carrying several chisels, which is attached to the drawbars and in which the chisels (140, 142) can be hydraulically adjusted laterally outwards and pushed under the lower edge of a shaft frame (150), - and an additional frame (54) which can be placed on the base frame (12) from below and can be quickly and detachably fastened to the same, the interior of which is slightly larger than the outer clearance profile of the shaft frame (150). 02) Shaft frame lifter according to claim 1, characterized in that - the additional frame (54) has a substantially rectangular, U-shaped outline. 03) Shaft frame lifter according to claim 1 or 2, characterized in that - the free legs (56, 58) of the additional frame (54) have end regions (62, 64) which are angled outwards and aligned with one another. JOCH-OIgDE
02 May 1996 04) Shaft frame lifter according to one of the preceding claims,
characterized in that - a holding member (70, 72) is fastened to the free leg or to its end region (62, 64) in such a way that the lower flange (76) of the U-shaped base frame (12) can be inserted into the gap (74) located between the holding member and the free leg. IQ 05) Shaft frame lifting device according to claim 4, characterized in that - an adjusting screw (80, 82) is screwed into the holding member (70, 72), the free screw end of which rests against the web of the U-shaped base frame (12). 6) Shaft frame lifter according to one of the preceding claims, characterized in that - a further holding member (86) is present on the additional frame (54) which can be fixed to the base frame (12) in a form-fitting and/or force-fitting manner such that the base frame (12) and the additional frame (54) can be firmly connected to one another. 07) Shaft frame lifter according to claim 6, characterized in that - the further holding member (86) is pivotally attached to the additional frame (54) in such a way that it can be attached to the base frame (12) in the folded-up state. 08) Shaft frame lifter according to claim 7, characterized in that - a locking part (90, 92) is attached to each of the two lateral ends of the further holding member (86), with which the further holding member (86) can be fastened to the base frame (12) in its raised position. 02 May 1996 ' II * II ? · '·« I". —3— 09) Shaft frame lifter according to claim 8, characterized in that - a holding plate (94) is attached to the base frame (12), behind which the locking part (90, 92) is movable and Q5 whereby the further holding member (86) can be fastened to the base frame (12). 10) Shaft frame lifter according to one of the preceding claims, ]_q characterized in that - the chisel-carrying chisel device (40) can be replaced and attached to the pull rods (22, 24, 26, 28). 11) Shaft frame lifter according to claim 10, ]_5 characterized in that - the chisel device (40) has two hanging links (132, 134), - each hanging link is hinged to a bearing point (133, 135) of a tie rod (26, 28), ~ the two bearing points (133, 135) of the two tie rods (2,6, 28) are kept at a constant mutual horizontal distance by a spacer (138), - a hydraulically actuated working cylinder (112) is provided, the piston rod (120) of which is articulated to a chisel (142) and the cylinder (112) of which is articulated to another chisel (140), - the chisels (140, 142) are firmly attached to the lower ends of the hanging links (132, 134), - the two hanging links (132, 134) or their lower ends are connected to one another by at least one tension spring (146, 148). 12) Shaft frame lifter according to claim 11, characterized in that - a tension spring (146, 148) is provided on each side of the working cylinder (112). JOCH-OIgDE 02. May 1996 » . i Il j ...... 13) Shaft frame lifter according to claim 10, characterized in that - the chisel device (40) has four hanging links (132, 134) Q5 - each hanging link is hinged to a bearing point (133, 135) of a tie rod (22, 24, 26, 28), - the four bearing points (133, 135) are maintained at a constant mutual, horizontal distance by two crosswise arranged spacers (138), IQ - four hydraulically operated working cylinders (153) arranged crosswise or in a star shape are present, - all four cylinders of the four working cylinders are firmly connected to each other, - each chisel (14 0, 142) is fixedly attached to the lower end of a hanging link (132, 134), - each chisel (140, 142) is pivotably mounted with its rear side (162) on the free end of the piston rod (160) of a working cylinder (153). 14) Shaft frame lifter according to claim 13, characterized in that - tension springs (14 6) arranged crosswise or in a star shape are present, which are attached to the lower ends of the hanging links. 15) Shaft frame lifter according to claim 10, characterized in that the chisel device has four hanging members (132, 134), - each hanging link is secured to a tie rod (22, 24, 26, 28) via two bearing points (133, 135) in a rotationally fixed manner, - there are four hydraulically actuated working cylinders (164) arranged crosswise or in a star shape, - all four cylinders of the four working cylinders are firmly connected to one another, 02 May 1996 'Il * II "&iacgr; · '·.?!*", ■—&ogr;— - each chisel (14 0, 142) is fixedly attached to the lower end of a hanging link (132, 134), - a bolt (121, 122) projects from the hanging link and engages in a sleeve (116, 118) which is firmly attached to the 05 rod (120) of the working cylinder (164) is attached, - tension springs (146) arranged crosswise or in a star shape are present, which are attached to the lower ends of the hanging links (132, 134).