US3027630A - Lifting tool - Google Patents

Description

April 1962 w. c. DE WlTT 3,027,630

\ LIFTING TOOL Filed May 1, 1959 INVENTOR. W144, G. fiJ/M United States Patent Qffice 3,027,630 Patented Apr. 3, 1962 3,027,630 LIFTING TOOL William C. De Witt, Milwaukee, Wis., assiguor to Square D Company, Detroit, Mich, a corporation of Michigan Filed May 1, 1959, Ser. No. 810,323 5 Claims. ((11. 29-240) The present invention relates to a tool which will facilitate the lifting of an extremely large and heavy lower enclosure portion of a housing to a collar or threaded portion of an upper enclosure portion of the housing and which will further facilitate rotating of the lower enclosure portion relative to the upper enclosure for assembling the housing. For the purpose of clarity the upper enclosure portion will be referred to hereafter as a top and the lower enclosure portion as a bottom or a bottom tank.

It has become necessary to completely enclose many electrical pieces of equipment in explosion proof enclosures or housings when the equipment is to be used in mines or in the oil and gas industry. A very convenient structure for enclosing the equipment comprises a top and a bottom which are screwed together. Such structures are now on the market wherein the top has a collar with external threads and the bottom has an upper end with internal threads so that it may be screwed onto the collar and thereby secured to the top to form a sealed joint between the top and bottom. When these housings become relatively large it becomes difficult to hold the bottom against the collar, align the threads and then turn the bottom to screw it onto the collar. This difficulty is particularly noticeable when there is no supporting structure which will hold a bottom, weighing many pounds more than a workman can safely lift and manipulate, in place during assembly, and when the heavy bottom is suspended entirely by the screw threads.

One of the main objects of the present invention is to provide a housing assembly tool which will facilitate the supporting, aligning and turning or screwing of the bottom onto or from the top.

A further object of the invention is to provide a housing assembly tool which may be used with housings of different sizes to support bottoms of several different sizes and which may be easily moved from one housing or enclosure to another so that a single tool may be used for a plurality of different housings.

A further object of the invention is to provide a housing assembly tool which will suspend the bottom in aligned position relative to the top and which will permit a workman to raise the bottom against the threads with one hand while he turns the bottom relative to the top with another hand to secure the bottom to the top.

Other objects and a fuller understanding of this invention may be had by referring to the following description and claims, taken in conjunction with the accompanying drawings in which:

FIGURE 1 is a side elevational view of the housing assembly tool in operative position on a tank.

FIGURE 2 is a cross sectional view taken along the line 2-2 of FIGURE 1.

FIGURE 3 is a sectional view taken along the line 33 of FIGURE 1.

. The description, drawings and claims jointly set forth one or more embodiments of the present invention and the present contribution to the art of providing a housing assembly tool which will facilitate the raising, rotating and fastening of the bottom of a housing to its supporting structure and top.

As illustrated in FIGURE 1, a piece of electrical equipment is enclosed in an explosion proof enclosure or housing comprising a top 10 and a bottom 11. The top 10 has a threaded collar 12 on the bottom side thereof onto which upper end 13 of bottom 11 is threaded for supporting bottom 11 on top 10. The bottom 11 may be large and heavy. For example in one size of housing, the bottom is approximately fifty inches in circumference, thirty inches in length and eighty pounds in weight. In other sizes of housings the bottoms may be larger. This makes it extremely difficult, if not almost impossible, for a single workman to raise one of these large bottoms against the threads on collar 12 and then turn it to threadably engage collar 12 and upper end 13 so that top 10 will support bottom 11.

The operation of suspending bottom 11 from top 10 is greatly facilitated by means of the herein described and claimed tool 15, which may be suspended on studs 16 extending outwardly from top 10 on diametrically opposite sides thereof.

Tool 15 comprises a pair of jacks 17 and 18 interconnected and simultaneously operated by a common handle 19. Jack 17 and the handle 19 are illustrated in FIGURE 1 while a portion of both jacks 17 and 18 are illustrated in FIGURE 2, the entire jack 18 not being illustrated since it is identical to the jack 17.

Jack 17 is constructed from a top plate 20, a bottom plate 21 and a handle clamp 22. The top plate 20 is provided at the upper end thereof with an opening 23 for receiving stud 16 and is provided at the lower end thereof with a pin 24. Between opening 23 and pin 24 is a second pin 25 extending parallel to pin 24 and disposed in a line drawn between opening 23 and pin 24.

Bottom plate 21 lies flat against top plate 20 and is movable at least towards or away from opening 23 and relative to top plate 20. As is further illustrated in the drawings bottom plate 21, at the end thereof closest to opening 23, is in operative engagement with a handle clamp 22. Bottom plate 21 on the opposite end thereof and on the side thereof engageable with top plate 20 has a pair of spaced wheels 26 and 27 which will face or be neXt adjacent bottom tank 11. Bottom plate 21 is further provided with a slot 28 which extends vertically or in a line at least parallel to and preferably coinciding with a line between opening 23 and pin 24 of top plate 29. Pin 24 extends through this slot 28 and has a head 24 overlying the surface of bottom plate 21 to prevent separation of top plate 29 and bottom plate 21. Pin 25 also extends through slot 23 as well as a pivot hole in clamp 22 to movably secure clamp 22 to plates 20 and 21. Bottom plate 21 also has a horizontal slot 29 disposed to one side of and transverse to slot 28. Horizontal slot 29 receives a stud 31} extending from and carried by handle clamp 22.

As was previously mentioned, handle clamp 22 is pivoted to top plate 20 by stud or pin 25, which extends through slot 28 in bottom plate 21. This pivotal mounting is obtained by providing handle clamp 22 with an angle member 32 and engaging the pivot pin 25 with one leg or side of the angle member 32. Slot 28 of bottom plate 21 cooperates with top plate 20 and with the pivot pin 25 to permit pivotal movement of handle clamp 22 relative to top plate 20 and bottom plate 21.

Handle clamp 22 is completed by providing a channel member 33 and a bolt 34, which extends through channel member 33 and another leg or side of angle member 32, to secure the free ends of channel member 33 against the leg of angle member 32 to clamp the respective end of common handle 19 therebetween. Common handle 19 is preferably of semi-circular shape so that one end is in handle clamp 22 of jack 17 and the other end is in the corresponding handle clamp of jack 1%.

The wheels 26 and 27, supported by bottom plate 21 are circumferentially spaced apart relative to bottom 11, or are spaced apart on opposite sides of a line extending through opening 23 and pin 24 and are adapted to support 1 bottom 11. The free ends of these wheels 26 and 27 are provided with flanges 26 and 27' respectively. The axis of rotation of the wheels are preferably at an angle to each other such that the axis of each wheel will extend approximately or exactly through the center of bottom 11 when bottom 11 is supported by the tool.

Bottom 11 is rotatably mounted on spaced wheels 26 and 27, as well as simultaneously on the corresponding wheels of jack 18, by providing a supporting ring 35, which rests on the wheels on jacks 17 and 18 and cooperates with one or more supporting abutments 36 on the outer surface of bottom 11. In this instance supporting ring 35 is provided at spaced intervals thereabout with inwardly extending sockets 37 each of which is engageable with its respective of the abutments 36.

In the operation of assembling bottom 11 onto top it), the workman simply hangs jacks 17 and 18 over the respective studs 16. Next he slips supporting ring 35 around bottom 11 so that sockets 37 engage their respective abutments 36 and then lifts supporting ring 35 and bottom 11 therewith into engagement with jacks 17 and 18 until circular ring 35 rests on the wheels 26 and 27' on jack 17 and the similar wheels on 18. The flanges on the wheels engage the inner periphery of circular ring 35 to keep bottom 11- directly under top and upper end 13 substantially in alignment with collar 12.

Following this the workman inserts the ends ofcommon handle 19 into the respective clamps, for example clamp 22, so that he may pivot handle clamp 22 relative to top plate 20 and bottom plate 21. As handle 19 is moved downwardly, from the position shown in solid in FIGURE 1 to the position shown in phantom by the dash-dot lines 19' in FIGURE 1, bottom 11 is lifted towards top It) to a position represented byline 11' to engage upper end 13 with collar 12. During this downward movement of handle 19, pivot pin and stud cause bottom plate 21 to move towards opening 23 and studs 16 while pin 24. and slot 28 hold the line of movement at least generally in the line extending between stud 16 and pin 24 or, in the drawings, in a vertical direction. When upper end 13 engages collar 12, circular ring is rotated by hand to rotate bottom 11 by means of sockets 37 engaging respective abutments 36 to thread upper end 13 onto collar 12. After upper end 13 is threaded onto collar 12, the tool 15 may be removed by simply, unhooking the jacks 17 and 18 from studs 16.

The same tool 15 may be used on different housings of different diameters. The dilferent diameter housings may be accommodated by putting the ends of handle 19 on the mean or extreme sides of bolts 34 in the handle clamps 22. For example, if the ends of handle 19 are on the sides of bolts 34 closest to bottom 11, jacks 17 and 18 are spaced apart to receive a larger diameter bottom 11 than if the ends of handle 19 are placed on the sides of bolts 34 furthest from bottom 11.

Although this invention has been described in its preferred form with a certain degree of particularity, it is understood that the present disclosure of the preferred form has been made only by way of example and that numerous changes in the details of construction and the combination and arrangement of parts may be resorted to without departing from the spirit and the scope of the invention as hereinafter claimed.

What is claimed is:

1. An apparatus for facilitating a threaded connection between two vertically disposed members comprising; a pair of oppositely faced jack means adapted to be individually suspended in horizontal alignment from the upper of said members on opposite sides of the upper member, a pair of horizontally aligned vertically movable rollers on each of the jack means, a ring means adapted to be non rotatably positioned on the lower of said members and engaging the rollers so as to be supported by the rollers for suspending the lower member on the upper member and an operating handle interjoining the pair of jack means for actuating. the jack means and vertically moving the rollers and ring means whereby the lower member may be simultaneously vertically raised and horizontally rotated relative to the upper member to achieve a threaded connection therebetween.

2. The invention as defined in claim 1 wherein each said jack means comprises a top plate, a handle clamp and a bottom plate disposed between the top plate and the handle clamp, said bottom plate having first and second slots therein disposed transversely to each other, pivot pin means extending through said first slot in said bottom plate and pivotally fastening said top plate and said handle clamp together, second pin means extending through the first slot in said bottom plate and secured to said topplate to prevent relative pivotal movement between said top and bottom plates and to allow movement of said bottom plate in a direction lengthwise of said first slot and relative to said top plate, and means on said handle clamp extending into said second slot to effect movement of said bottom plate relative to said top plate upon pivotal movement of said handle clamp relative to said top and bottom plates, thereby to raise said lower member against the upper member upon operation of said jack means by saidoperating handle.

3. The structure as recited in claim 1 wherein the lower member has spaced abutments on the external surface thereof and the ring means has inwardly extending socketsv adapted to receive the spaced abutments for simultaneous-- ly supporting the lower member and'effecting a non rotatable connection therebetween.

4. A housing assembly tool for facilitating the attachment of a bottom to a top of a housing for electrical apparatus, said top including a collar provided with threads, said bottom having spaced supporting abutments on the external surface thereof and including threaded means engageable with said threads on said top whereby said top will support said bottom when said threaded means and said collar are in threaded engagement, said tool comprising a pair of oppositely faced jack means adapted to be individually suspended in horizontal alignment from the top of the housing on opposed sides thereof, each of said jack means including a top plate adapted to engage a portion of the top for suspending the jack means on the top, a handle clamp and a bottom plate disposed between the top plate and the handle clamp, said bottom plate havingfirst and second slots therein disposed transversely to each other, pivot pin means extending through the first slot in said bottom plate and pivotally fastening said top plate and said handle clamp, second pin means extending through first slot in said bottom plate and secured to said top plate to prevent relative pivotal movement between said top and bottom plates and to allow movement of said bottom plate in a direction lengthwise of said first slot and relative to said top plate, and means on said handle clamp extending into said second slot to effect movement of said bottom plate relative to said top plate upon pivotal movement of said handle clamp relative to said top and bottom plates, an operating handle interjoining the handle clamps of the pair of jack means to operate the pair of jack means simultaneously, ring means having inwardly extending socket members adapted to engage the abutments on the bottom for simultaneously supporting the bottom and for effecting transfer of rotary movement from said ring means to said bottom upon rotary movement of said ring means, support wheels spaced in horizontal alignment on opposite sides of the first slot of each of said bottom plates engaging said ring means for rotatably supporting said ring means whereby said bottom may be rotated relative to said top during operation of said jack means to engage said threaded means with the threads on said collar.

5. An apparatus for facilitating a threaded connection between two vertically disposed threaded members, comprising; a pair of oppositely faced jack means each having; a top portion adapted to engage a hook on the upper of the members for individually suspending the jack means in horizontal alignment on opposed sides of the upper member, a bottom portion vertically movable relative to the top portion a pair of horizontally aligned spaced rollers on the bottom portion, and a pivotal handle clamp connected to vertically move the bottom portion relative to the top portion upon pivotal movement of the handle clamp, an operating handle connected to the handle clamps of both jack means for pivoting the handle clamps and a ring means having a portion adapted to non rotatably engage the lower of said threaded members and a second portion in engagement with and supported on the rollers on both bottom portions for suspending the lower member and for vertically raising the lower member when the operating handle is moved to pivot the handle clamps and for rotating the lower member relative to the upper member when the second portion of the ring means is moved on the rollers.

References Cited in the file of this patent UNITED STATES PATENTS

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