WO2000006484A1

WO2000006484A1 - Tubular extension arm

Info

Publication number: WO2000006484A1
Application number: PCT/IB1999/001443
Authority: WO
Inventors: Robert Mooy; Wayne Doswell
Original assignee: Ventra Group, Inc.
Priority date: 1998-07-31
Filing date: 1999-07-30
Publication date: 2000-02-10

Abstract

The present invention relates to an extension arm (10) for use in conjunction with a vehicle jack having a rotatable torque receiving member (14') that rotates under an application of torque so as to affect jack raising and lowering movements during the vehicle jacking operation. The extension arm comprises an elongated tubular body (16) having first and second opposing end portions. A first tubular torque coupling member (14') is defined at the first end of the elongated tubular body (16), and a second torque coupling member (12) is defined at the second end of the elongated tubular body (16). The second torque coupling member (12) provides interior surfaces (18) defining a socket (20) that is shaped to removably receive a first tubular torque coupling member (14') of an adjoining extension arm (10) in a mated, torque transmitting relationship.

Description

TUBULAR EXTENSION ARM

Field of the Invention

The piesent invention relates to lifting jacks used foi automobiles and othei vehicles and, in paiticulai, relates to an extension arm used to operate such a jack

Backgiound of the Invention

In the automotive industry it is common to provide a portable jack that is stoied in the \ ehicle to enable an operator to lift a portion of the vehicle to affect a lepan such as changing a tne Most conventional jacks are driven eithei by a levei oi a ci ank w hich in turn drives gears and/or sciews in the jack to obtain a sufficient mechanical

antage toi laising the vehicle Dunng a vehicle raising operation, the jack is located undei the portion of the vehicle to be lifted and engaged underneath an adjacent solid membei w hich can bear the vehicle's weight Sometimes, particularly with tiucks the ]ack must be located fai under the vehicle or in othei positions where it is aw kw id oi difficult to access the jack dunng opeiation Accoidingly, it has become common pi actice to piovide an extension arm to permit the opeiator to opeiate the jack fiom a distance These extension arms are often bioken down into sevei al similai sections which are coupled end to end in a toique transmitting relationship w hen the jack is to be opeiated One such extension arm assembly is disclosed in U S Patent No 5,381,707, the entirety of which is heieby incorporated into the present application by iefeience

One know n type of extension arm comprises a number of sections of round tubing Each interconnecting end of each section is formed squaie or rectangular to transmit toique One end of each section has a laigei cross section than the othei end so that the smallei end of one section can fit snugly into the larger end of an adjoining section The squared ends allow the joined sections to -transmit torque fiom one to another and to the jack To reduce the cost and. weight of these extension arms, it would be desirable to make the extension arm from a thinner gauge of metal. However, simply using a thinner gauge of metal weakens the torsional rigidity of the extension arm's torque transmitting end. This can lead to deformation of the torque transmitting end after a number of uses and therefore becomes inoperable. Extensive deformation of the torque transmitting end can provide it with a rounded configuration, which makes it difficult to achieve any satisfactory transmission of torque. Consequently, there exists a need for an extension arm that is capable of being formed from a thinner gauge of metal than is conventionally used and has sufficient torsional rigidity at the torque transmitting end thereof to resist deformation during vehicle raising operations.

Summary of the Invention

To meet the above-described need, one aspect of the present invention provides an extension arm for use in conjunction with a vehicle jack having a rotatable torque receiving member that rotates under an application of torque so as to affect jack raising and lowering movements during the vehicle jacking operation. The extension arm comprises an elongated tubular body having first and second opposing end portions. A first tubular torque coupling member is defined at the first end of the elongated tubular body, and a second torque coupling member is defined at the second end of the elongated tubular body.

The second torque coupling member provides interior surfaces defining a socket that is shaped to removably receive a first tubular torque coupling member of an adjoining extension arm in a mated, torque transmitting relationship so that one of the first torque coupling member of the extension arm and a second torque coupling end of the adjoining extension arm can be coupled to the torque receiving member of the jack in a torque transmitting relationship and then torquing movements can be applied to the other of the extension arm and the adjoining extension arm so as to transmit torque to the torque receiving member of the jack via the aforesaid mated, torque transmitting relationships to thereby affect rotation of the torque receiving member. The second torque coupling member has a strengthening rib extending on the exterior thereof in a generally circumferential direction to increase the torsional rigidity of the second torque coupling member.

The rib provides the extension arm with enhanced torsional rigidity at its second torque coupling member without the need for utilizing a thicker gauge material, which in turn lowers the material costs for manufacturing the arms. Likewise, the rib can allow a thinner gauge of metal to be used without sacrificing torsional rigidity. For a further increase in torsional rigidity, a plurality of such ribs may be fprmed on the exterior of the second torque coupling member. Other aspects of the invention relates to a jack assembly comprising a vehicle jack and an extension arm and an extension arm assembly comprising a plurality of extension arms.

Other objects, features, and advantages of the present invention will become apparent from the following' detailed description, the accompanying drawings,, and the appended claims.

Brief Description of the Drawings

Fig. 1 is a perspective view of the torque transmitting end of a tubular extension arm constructed in accordance with the principles of the present invention; Fig. 2 is a side-view of the torque transmitting end of the tubular extension arm of Fig. 1;

Fig. 3 is a cross-sectional view of the torque transmitting end of the extension .arm shown in Fig. 1; and

Fig. 4 is a cross-sectional view of the torque transmitting end of the extension arm of Fig. 1 coupled to a torque receiving end of another extension arm.

Detailed Description of the Preferred Embodiment of the Invention

Figs. 1-4 illustrate a tubular extension arm 10 constructed in accordance with the principles of the present invention. The extension arm 10 is of the type shown in the above-incorporated '707 patent and is designed to permit operation of a vehicle jack at a distance therefrom. More specifically, the extension arm 10 is designed to allow the user to transmit torque to the drive screw and/or gears of the jack at a distance therefrom.

The extension arm 10 has a tubular metal body 16 with a torque transmitting end 12 and a torque receiving end which has a similar configuration to the torque receiving end 14' of the .adjoining extension arm 10' shown in Fig. 4. The arm 10 shown in the Figures is elongated and generally straight, but it is within the

ISA/EP scope of the present invention to bend the arm 10 at an intermediate portion thereof so that the torque receiving end can be used in a cranking manner The torque transmitting end 12 of the extension arm 10 has a larger diametrical size than the remainder of the arm 10 The tubular body 16 provides interior surfaces 18 at the toique transmitting end 12 thereof that cooperate to define a socket 20 The shape of the socket 20 may be square, as shown, hexagonal, or any other such shape

The torque receiving end has a shape corresponding to the shape of the socket 20 so that a series of these extension arms 10 can be coupled together with the torque leceiving ends thereof received in a mated, torque transmitting relationship within respective sockets 20 in the torque transmitting ends 12 of adjoining extension arms 10 This coupling is depicted best in Fig 4 between the torque transmitting end

12 of extension arm 10 and the torque receiving end 14' of extension arm 10' Once these extension arms 10 are coupled together in a turoque transmitting relationship, the socket 20 of the extension arm 10 proximate the vehicle jack (not shown) can be fit onto a rotatable lug or other type of rotatable torque receiving member of the jack's iaising and lowering mechanism in a torque transmitting relationship Then, the user can iotate the extension arm 10 distal the jack to impart rotation to the jack lug, theieby transmitting torque to the jack's raising and lowering mechanism from a distance The distal torque receiving end may be rotated using an L-shaped extension aim having a torque transmitting end 12 similar to the end 12 of the straight extension arm 10 shown, a crank handle as shown in the above-incorporated '707 patent, a wrench, or any other suitable means for rotating the distal extension arm 10

It is to be understood that the torque transmitting and receiving ends of the extension arm 10 may be reversed That, is the end of the arm 10 with the socket theieon ma> be the end that receives torque and the end without the socket may the end that applies toique Thus, either the torque transmitting end 12 or the torque leceivmg end may be considered a torque coupling member in the broad sense of the invention

To torsionally strengthen the body 16 at the torque transmitting end 12, an annular πb 22 is provided The rib 22 extends generally circumferentially around the exterior of the torque transmitting end 12 and increases its torsional rigidity As a result, the body 16 can be formed from a thinner piece of metal than would otherwise be necessary to achieve the torsional rigidity piovided to the torque transmitting end 12 b> the rib 22 Comparing an extension aim with the rib 22 to an extension arm without the rib, it is believed that the rib 22 provides for a 20% increase in torsional strength.

To form the rib 22, a swaging tool (not shown) is inserted into the socket 20 and portions thereof are engaged with the interior surfaces of the socket to diametrically expand the portion of the metal material surrounding the socket 20 so as to form the annular rib 22. The free end of the torque transmitting end 12 may be pushed axially inwardly as the metal material is being diametrically expanded to enhance formation of the rib 22. Any other method for integrally forming the rib 22 with the metal material of the extension arm 10 may be used in place of the swaging operation. Alternatively, the rib 22 may be formed separately as an annular ring and then be attached to the exterior of the torque transmitting end 12 by welding or the like. However, swaging is the preferred method of forming the rib 22.

The torque transmitting end 12 also has an opening 26 formed through the wall thereof. This opening is provided to accomodate receipt of a relaseable lock button of the type shown in U.S. Patent No. 5,237,890, the entirety of which is hereby incorporated into the present application by reference.

The extension arm 10 of the present invention may be packaged together with a vehicle jack as a vehicle jack assembly. The jack used may be the pantographic-type jack as shown in U.S. Patent No. 5,692,730, the half-scissors jack shown in U.S. Patent Application of Gill, Ser. No. 08/979,343. or any other type of vehicle jack. The entirety of the aforementioned '730 patent and the aforementioned '343 application are each incorporated in their entirety into the present application by reference. Further, a plurality of these extension arms may be considered together as an extension arm assembly that is to be used with a vehicle jack for raising and lowering operations.

It can thus be appreciated that the objectives of the present invention have been fully and effectively accomplished by the foregoing specific embodiment. It is to be understood, however, that the foregoing embodiment has been provided solely to illustrate the structural and functional principles of the present invention and is not intended to be limiting. In contrast, the present invention is intended to encompass all alterations, modifications, and substitutions within the spirit and scope of the appended claims.

Claims

What is Claimed

1 An extension arm for use in conjunction with a vehicle jack during a vehicle jacking operation, the vehicle jack having a torque receiving member that is constiucted and arranged to be rotated under an application of torque so as to affect jack raising and lowering movements during the vehicle jacking operation, said extension arm comprising an elongated tubular body having first and second opposing end portions, a fust tubular torque coupling member defined at the first end of said elongated tubulai body, a second torque coupling membei defined at the second end of said elongated tubular body, said second torque coupling membei providing interior suifaces defining a socket that is shaped to remov ably receive a first tubular torque coupling member of an adjoining extension arm in a mated, torque transmitting relationship so that one of the first torque coupling member of said extension arm and a second torque coupling end of said adjoining extension arm can be coupled to the torque leceiving member of the jack in a torque transmitting relationship and then torquing movements can be applied to the other of said extension arm and said adjoining extension aim so as to transmit torque to the torque receiving member of the jack via the aforesaid mated, torque transmitting relationships to thereby affect rotation of the toique receiving member, said second torque coupling member having a strengthening rib extending in a generally circumferential direction on the exterior thereof to increase the toisional ╧Çgidity of said second torque coupling member

2 An extension arm according to claim 1, wherein said strengthening ╧Çb is formed integrally with said second torque coupling member

3 An extension arm according to claim 2 wherein said strengthening rib is integrally formed by swaging the interior of said second torque coupling member

4. An extension arm according to claim 1, wherein said socket has a generally square cross-sectional shape.

5. A vehicle jack assembly for performing a vehicle jacking operation, comprising: a vehicle jack having a base, a load rest, and a raising and lowering mechanism operatively connected between said base and said load rest; said raising and lowering mechanism having a rotatable torque receiving member, said raising and lowering mechanism being constructed and arranged such that rotating said torque receiving member under an application of torque affects relative raising and lowering movements between said load rest and said base during the vehicle jacking operation; an extension arm comprising: an elongated tubular body having first and second opposing end portions; a tubular torque coupling member defined at the first end portion of said elongated tubular body, said first torque coupling member providing interior surfaces defining a socket that is shaped to removably receive said torque receiving member of said jack in a mated, torque transmitting relationship so that torquing movements can be applied to the second end portion of said extension arm so as to transmit torque to the torque receiving member of the jack via the aforesaid mated, torque transmitting relationship to thereby affect rotation of the torque receiving member; said torque coupling member having a strengthening rib extending in a generally circumferential direction on the exterior thereof to increase the torsional rigidity of said torque coupling member.

6. A vehicle jack assembly according to claim 5, wherein said strengthening rib is formed integrally with said torque coupling member.

7. A vehicle jack assembly according to claim 6, wherein said strengthening rib is integrally formed by swaging the interior of said second torque coupling member.

8 A vehicle jack assembly according to claim 5, wherein said socket has a generally square cross-sectional shape

9 A vehicle jack assembly according to claim 5, wherein said vehicle jack is a pantographic jack with four jack arms

10 A vehicle jack assembly according to claim 5, wherein said vehicle jack is a half-scissors jack with only two jack arms

1 1 An extension arm assembly for use in conjunction with a vehicle jack during a vehicle jacking operation, the vehicle jack having a torque leceivmg member that is constructed and arranged to be rotated under an application of torque so as to affect jack raising and lowering movements during the vehicle jacking operation said extension arm assembly comprising a fust extension arm comprising an elongated tubular body having first and second opposing end portions, a first tubular torque coupling member defined at the fust end of said elongated tubular body, a second torque coupling membei defined at the second end of said elongated tubular body, said second torque coupling membei providing interior surfaces defining a socket that is shaped to removably receive said torque receiving member of said jack in a first mated, toique transmitting relationship so that torquing movements applied to said first extension arm transmit torque to the torque receiv ing member of the jack via the aforesaid first mated, torque tiansmittmg relationship to thereby affect rotation of the torque receiv ing member, said second torque coupling member having a strengthening rib extending in a generally circumferential direction on the exte╧Çoi thereof to increase the torsional rigidity of said second torque coupling member, and a second extension arm comprising an elongated tubular body having first and second opposing end portions; a tubular torque coupling member defined at the first end portion of said elongated tubular body, said first torque coupling member providing interior surfaces defining a socket that is shaped to removably receive said first torque coupling end of said first extension arm in a second mated, torque transmitting relationship so that torquing movements can be applied to the second end portion of said extension arm so as to transmit torque to said first extension arm via the aforesaid second mated, torque transmitting relationship which torque is ultimately transmitted through said first extension arm to the torque receiving member of said jack via the aforesaid first mated, torque transmitting relationship when the second torque coupling member is coupled with the torque receiving member of said jack. said torque coupling member having a strengthening rib extending in a generally circumferential direction on the exterior thereof to increase the torsional rigidity of said torque coupling member.

12. An extension arm assembly according to claim 1 1 , wherein said strengthening rib of the second torque coupling member of said first extension arm and said strengthening rib of the torque coupling member of said second extension arm are each formed integrally with their respective torque coupling members.

13. An extension arm assembly according to claim 12, wherein said strengthening ribs are integrally formed by swaging the interiors of their respective torque coupling members.

14. An extension arm assembly according to claim 1 1 , wherein said sockets each have a generally square cross-sectional shape.