US2952373A

US2952373A - Manhole cover lifter

Info

Publication number: US2952373A
Application number: US674951A
Authority: US
Inventors: Edward L Bie
Original assignee: WESTERN PROGRESS MANUFACTURERS
Current assignee: WESTERN PROGRESS MANUFACTURERS
Priority date: 1957-07-29
Filing date: 1957-07-29
Publication date: 1960-09-13
Anticipated expiration: 1977-09-13

Description

Sept. 13, 1960 E. L. BIE

MANHOLE COVER LIFTER R. [dM/arc/ L 5 1'6 INV 2 Sheets-Sheet l V r N@\%\\@ Filed July 29, 1957 N M-HJIHH ATTORNEYI Sept. 13, 1960 E. L. BIE

MANHOLE COVER LIFTER 2 Sheets-Sheet 2 Filed July 29, 1957 m mH-l hul mm mm R m I I mm Q mm Hnmn United States Patent 2,952,373 MANHOLE COVER LIFTER Edward L. Bie, Menlo Park, Calif, assignor to Western Progress Manufacturers, Palo Alto, Calif, a partner- This invention relates lifters.

In the past manhole covers have generally been lifted by hand, that is by one or two individuals using hand hooks to grasp the manhole covers. Frequently the covers are so heavy that more than one man is required. The heavy lifting involved, in addition to being laborious, is often dangerous because it may strain or injure the backs of the lifters.

In general, it is an object of the present invention to provide a manhole cover lifter by which manhole cgvers may be readily lifted by one man with very little e ort.

Another object of the invention is to provide a lifter of the above character in which the manhole cover can be readily moved after it has been lifted.

Another object of the invention is to provide a lifter of the above character which is readily adaptable for lifting difierent types of manhole covers.

Another object of the invention is to provide a lifter of the above character which can be folded up when not in use and which is readily transportable.

Additional objects and features of the invention will appear from the following description in which the preferred embodiment has been set forth in detail in conjunction with the accompanying drawing.

Referring to the drawing:

Figure 1 is a front elevational view showing my manhole cover lifter being utilized for lifting manhole covers of the type having a pair of slots in the periphery of the cover.

Figure 2 is a side elevational view of the manhole cover lifter shown in Figure 1.

Figure 3 is a side elevational view of my manhole cover lifter showing the position of the lifter just before lifting takes place.

Figure 4 is a front elevational view showing my manhole cover lifter in a folded up position.

Figure 5 is a plan view of the manhole cover lifter shown in Figure 4.

Figure 6 is a left hand elevational view of the manhole cover lifter shown in Figure 4.

Figure 7 is a cross sectional view taken along the line 77 of Figure 4.

Figure 8 is a detail view of the handle assembly.

The manhole cover illustrated in the drawing consists generally of a frame 11 of suitable material such as channel iron. The frame 11 is substantially in the form of an inverted U with an intermediate horizontal portion 11a and depending vertical leg portions 11b and 110. It will be noted that the intermediate portion 11a is relatively long whereas the leg portions 11b and 110 are relatively short. It will also be noted that the frame 11 lies in one plane. The horizontal portion 11a is provided with suitable reinforcing such as the channel member 12 which is fixed to the horizontal portion 11a.

A wheel 13 is mounted on the lower end of each of generally to manhole cover the leg portions 11b and by suitable means such as a stud bolt 14 which is fixed to the lower end of the leg portions 11b and 110 and upon which the wheel 13 rotatably mounted by suitable means such as roller bearings (not shown). A pin 16 mounted in the outer end of the bolt 14 serves to hold the wheel in place.

A mounting block 18 is slidably mounted on the intermediate portion 11a of the frame and may be moved from a position adjacent the leg portion 11b to a position adjacent the stop 19 fixed to the frame. The mounting block 18 is in the form of a rectangular member having a rectangular opening therein to accommodate the rectangular configuration of the channel iron forming the intermediate portion 11a.

An L-shaped lifting member 21 is pivotally mounted on the mounting block 18 by suitable means such as a cap screw 22. A handle 23 consisting of two or more sections is fixed to the L-shaped lifting member 21 by suitable means such as welding. The handle as shown is comprised of two

sections

24 and 26, section 26 telescoping within section 24.

Suitable means is provided for retaining the telescoping section 26 in an extended position. As shown, particularly in Figure 6, the telescoping section 26 is provided with an enlarged portion at its lower end which is adapted to engage an inwardly extending portion on the upper end of the section 24 to prevent removal of the section 26. When the telescoping section 26 is pulled out so that the portion 27 engages the portion 28, a pin 29 is pressed outwardly over the edge of the section 24 by a spring 31 to prevent collapse of the section 26. A collar '32 formed on the pin 29 prevents loss of the pin 29. The lower end of the section 24 is closed with a plug 33 to prevent the. section 26 from dropping out of the section 24.

A handle catch 36 is mounted on an extension 37 provided on the mounting block 18. The handle catch consists of a plate-like member 38 which carries a pair of ears 39 extending upwardly on both sides of the extension 37. The end of the plate-like member 38 opposite the ears 39 is carried by mounting posts 41 fixed to the extension 37. A screw 42 carrying a spring 43 is threadedly mounted into the post 41. The spring 43 serves to urge the ears 39 of the handle catch into a position in which the ears are normally in a position above the top surface of the extension 37.

Means is provided for engaging the handle in a collapsed or telescoped position and consists of a member 46 which is fixed to the leg portion 110 and slidably car ries a hand operated bolt 47. The bolt 47 is normally pressed inwardly towards an extended position by spring 48 one end of which engages the member 46 and the other end of which engages the blunt flanged end 49 of the bolt. The blunt end 49 is adapted to seat in the outer end of the extension 26 in a manner hereinafter described.

My manhole cover lifter also includes a flexible member in the form of a chain 51 which is provided with a suitable manhole cover engaging means. As shown, the engaging means consists of a hook 52 mounted on one end of the chain and a second hook 53 mounted on one of the links of the chain near the other end of the chain. A ring 54 is mounted on the other end of the chain for a purpose hereinafter desribed. The L-shaped lifting member 21 is provided with a notch 56 which is adapted to receive a link of the chain as hereinafter described.

Operation of my manhole cover lifter may now be briefly described as follows: Let it be assumed that my manhole cover lifter is in the position shown in Figure 4 in which the handle is collapsed and has been folded to r i I 2,952,373

a position in which it extends in a line parallel with the longitudinal axis of the frame 11 and that the handle is held in this position by the hand operated bolt 47 To release the handle, the hand operated bolt 47 is retracted and the handle is swung clockwise as viewed in Figure '5 about the pivot formed by the cap screw 22. When the L-shaped member 21 to which the handle is attached is near the, handle catch 36, the handle catch 36 is retracted until the L-shaped member overlies the extension 37 at which time the handle catch is released to permit the ears 29 to move upwardly along the sides of the L-shaped member 21 to prevent further rotation of the handle.

The mounting block 18 and the handle may then be slid to the right as viewed in Figure until the block 18 engages the stop 19 at which point the center of the handle will be at the center of the frame 11. The handle extension 26 is then extended until the pin 29 engages the outer edge of the handle section 24.

The device is now ready for a manhole cover lifting operation The device is pushed over a manhole cover 6 1 such as shown in the drawing so that the wheels 13 straddle the manhole cover. The

hooks

52 and 53 on the chain 51 are dropped into the slots 62 in the manhole cover so that they engage the manhole cover and then an intermediate portion of the chain 5 1 is dropped over the top of the -L-shaped member 21 as shown in Figure 2 while the handle of the lifter is in a raised position substantially as shown in Figure 3. Then to lift the manhole cover, it is merely necessary to push downwardly on the outer end of the handle which serves as a lever arm to raise the manhole cover as the Wheels 13 are shifted into a position immediately underlying the point at which the chain 51 is attached to lift the manhole cover to an elevated position as shown in Figure 1. The manhole cover may then be wheeled in either a forward or backward position from the manhole and lowered onto the ground by allowing the handle to move upwardly. When the operation for which the manhole was removed has been completed, the manhole cover may then be lifted and moved into place and lowered in a manner similar to that hereinbefore described.

Certain manhole covers are provided with only one opening and in that case, only one of the

hooks

52 or 53 is utilized. One of the links of the chain 51 is then dropped into the notch 56 when the handle is in a raised position and then the manhole cover may then be lifted in the same manner as hereinbefore described. The ring 54 has been provided for convenience in lifting the chain and for hooking and unhooking manhole covers.

It is readily apparent that the operation hereinbefore described can be readily performed by one person with ease. Very heavy manhole covers may be lifted with this device with very little effort on the part of the operator because of the long lever arm provided by the handle 23.

After the lifting operation has been completed, the handle may be returned to the position shown in Figure 4 by pushing in the pin 29 and collapsing the handle and then swinging the handle to a positon in which it is parallel to the longitudinal axis of the frame 11. The handle may then be engaged by the hand operated bolt 47.

When the device is in a collapsed position, it may be readily carried about or stored in a very small space.

It is apparent from the foregoing that the use of my manhole cover lifter is particularly advantageous in that heavy manhole covers can be lifted by one person with very little effort and without the danger of causing backstrain or injury.

I claim:

l. In a manhole cover lifter, a frame substantially in the form of an inverted U with an intermediate substantially horizontal portion and depending substantially vertical leg portions, a wheel rotatably mounted on the lower end of each of the leg portions of said frame, a mounting member slidably mounted on the intermediate portion of said U-shaped member and movable between a position adjacent one of said leg portions and a position substantially equidistant from the leg portions, an extensible handle pivotally mounted on said mounting member and movable between a position at right angles to the longitudinal axis of the frame and a position substantially parallel to the longitudinal axis of the frame, a releasable handle catch carried by said mounting member, said releasable handle catch being adapted to releasablyretain said handle in a position substantially at right angles to the longitudinal axis of the frame, said handle being movable between extended and retracted positions, and means carried by the frame for releasably engaging the outer end of the handle when the handle is retracted and in a position parallel to the longitudinal axis of the frame, a flexible non-extensible member having manhole cover engaging means mounted thereon, and means mounted on said frame for engaging said flexible nonextensible member whereby when said manhole cover engaging means is engaging a manhole cover said manhole cover may be raised or lowered by tilting of the handle.

2. In a manhole cover lifter, a frame substantially in the form of an inverted U with an intermediate substantially horizontal portion and depending substantially vertical leg portions, a wheel rotatably mounted on the lower end of each of the leg portions of said frame, a handle slidably mounted on said frame intermediate the leg portions of the frame for movement longitudinally of the intermediate horizontal portions of the frame and extending at right angles to the longitudinal axis of the frame, said handle being movable between a position at right angles to the longitudinal axis of the frame and a position parallel to the longitudinal axis of the frame, said handle also being movable between extended and retracted positions, means. for retaining said handle in a retracted position when said handle is in a position substantially parallel to the longitudinal axis of the frame, a flexible nonextensible member having manhole cover engaging means mounted thereon, and means for securing said flexible nonextensible member to said frame whereby when a manhole cover is engaged by the manhole cover engaging means and the flexible nonextensible member is secured to said frame said manhole cover may be lifted as the outer end of the handle is lowered when the handle is in an extended position and in a position at right angles to the longitudinal axis of the frame.

References Cited in the file of this patent UNITED STATES PATENTS 687,860 Smart Dec. 3, 1901 1,019,345 Needham Mar. 5, 1912 1,681,944 Marshall Aug. 28, 1928 2,598,489 Bayer et al. May 27, 1952 2,846,259 Sadler Aug. 5, 1958