WO1999067112A1

WO1999067112A1 - Support jack structure

Info

Publication number: WO1999067112A1
Application number: PCT/FI1999/000561
Authority: WO
Inventors: Kauko Koskinen
Original assignee: Kauko Koskinen
Priority date: 1998-06-25
Filing date: 1999-06-24
Publication date: 1999-12-29
Also published as: AU4788299A; FI981462A0; FI981462A; EP1089900A1

Abstract

A folding jack construction comprising a jack (16) articulated (11) from its upper end, a supporting arm (15) articulated (12) from its upper end, by means of which said jack is supported into immobile position, and a turning shaft (6) including nut (9) on its worm portion (8), whereby the joint said jack is arranged into the said nut. The jack (16) movement down to its position of support is arranged to work by means of the moving nut so that a slight axial movement of the nut releases the jack to turn down around the joint, whereby also supporting arm (15) is released due to its joint (12) to turn down into contact with said jack, and that there are between supporting arm and jack several mutual locking points, most suitably arranged by cogging (2).

Description

SUPPORT JACK STRUCTURE

The invention relates to an adjustably mountable support jack structure suited especially for easy and fast support of vehicles , trailers, market-stalls or counters to be hauled.

Previously known as corner support of camping trailers a folding jack let down to the ground by turning a long worm until an articulated supporting arm resting on the worm has pushed one end of the jack to the ground, while the other end is by means of a joint pin fixed to the trailer bottom. Such a construction is described, for instance, by the publication DE 805 1 15.

In the known solution the spindle must be turned quite a lot in order to make the jack pierce into the ground. likewise, by lifting the jack the same amount of turning is needed. A long worm is exposed to dirt while driving and, when the worm is lubricated, dirt and sand easily accumulates in the threads.

In US patent 2,672,318 free drop of jack before turning is described, whereby the amount of turning sinks. Yet, the jack must be lifted as a separate operation, when no support is needed.

By means of the solution according to this invention the described disadvantages are avoided and the invention is characterized in what is presented in the enclosed c laims.

The advantage of the invention is that letting down and lifting the jack are carried out by a quick-motion with very little turning and, in addition, a rather short additional twist is needed in order to produce a tightening lift and, correspondingly, turning in other direction to abolish lifting while lifting the jack. For the motions required by this solution very short thread portion is sufficient. The jacks retain their raised position reliably without any additional steps. The jack stability in all directions is easily accomplished increasing the structural width of the jack, at least in the jack upper end.

In the following the invention is disclosed with reference to the enclosed drawing, where,

Fig. 1 shows a jack construction, jack up.

Fig. 2 shows the above jack construction, jack down.

Fig. 3 shows another jack construction, jack down.

Fig. 4 shows the jack supporting function of the other jack construction. Fig. 5 shows an optional supporting function of the jack. Figure 1 is an jack lifted up and fixed, for instance, to a camping trailer. Jack 1 is folded up around joint 1 1. The jack was lifted up and its position retained by nut 9 shifted by means of screw 8, the right end of which pushes jack from its upper end forcing it to fold-up. Jack 1 has, simultaneously, lifted supporting arm 3, which is articulated by fulcrum pin 12 to turn to nut 9. Shaft 6 furnished with worm 8 is fixed rotationally to frame 7 and the axial motion is prevented by flanges 10. Supporting arm 3 has a spring 4, which on lifting the supporting arm is tensed to the position as per the figure, when the bend of spring 4 is changed by projection arm 20 of frame 7.

Figure 2 shows the process of letting the jack 1 down. Shaft 6 has been shifted from nut 5 till nut 9 has glided so much to the left that the jack upper part is released to turn to the left and the jack 1 lower end sinks to the ground. At the same time the other end of supporting arm 3 has also been free to drop down into cogging 2 in the jack. By further turning of nut 5 the nut 9 travels more to the right and supporting arm 3 presses the jack 1 further down and more erect in order to increase supporting. This is produced only by turning from nut 5 a relatively small thread portion in the same direction.

When wanting to lift the jack 1 , at first spring 4 must be stretched to the opposite bending status in its holder 13. This is done for instance through pressing spring

4 at the arrow or pressing the spring at holder 13 according to the arrow. When the spring is stretched according to the left-hand figure, jack 1 can be lifted only by turning shaft 6 in another direction than by letting down. Nut 9 moves to the right pushing the jack up. At the same time, the supporting arm 3 goes up. Spring 4 releases the jack from the cog, when nut is slightly shifted to the right and the tension of supporting arm 3 on jack 1 lessened.

Figure 3 there shows another version, where shaft 6 has been turned so much that nut 9 has moved to the left allowing jack 16 articulated in nut 9 to turn down. Projection 18 of frame 14 eventually allows jack 16 to turn down. When jack 16 reaches the ground, the additional turning of shaft 6 even starts to shift shaft 6 to the right as much as distance s, whereby supporting am 15 can turn down according to figure 4. Flange 19 on shaft 6 does not anymore press the flange with loose holes in the top of supporting arm 15 and the supporting arm can turn down. The supporting arm has a cogging that is locked in crossbar 17 in jack 16. Then additional turning of shaft 16 only puts jack 16 more erect increasing the support.

On lifting jack 16, at first nut 9 glides to the right and the strain of jack against the ground decreases. When jack 16 reaches frame 14 the nut of projection 18 does not move to the right anymore but then shaft 6 starts to move to the left. This forces flange 19 of shaft 6 to push, at first, supporting arm 15 off its locking in the cog and then to lift the supporting arm up. When shaft 6 has moved to the left as much as distance s, nut 9, in its turn, starts again its motion to the right, while turning of shaft goes on, whereby projection 18 of frame 14 finally forces jack 16 also up beside supporting arm 15. Jack 16 and supporting arm 15 move automatically into and out off support only by turning shaft 6 in different directions. Since jack 16 is heavier than supporting arm, it drops down before the supporting arm. For the same reason supporting arm 15 goes up before jack 16.

Also in this version jack down-up operations work by relatively small turning of the shaft, for which only a minor additional turning of the shaft is needed in order to tighten the support.

Nut 9 is arranged to glide along frame 14 or 7, whereby no bending is caused to shaft 6 due to supporting force. When worm 8 is short, it can easily be protected against dirt and dust using a folding rubber hose.

The part suitable for shaft 6 turning, as nut 5, can be in any of the shaft, whereby the direction of the jack location can be chosen and the jack operation controlled from different sides.

Figure 5 shows a version, where nut 21 is round at least in its lower edge, whereby the nut rolls along the jack surface, when the jack is moving up. The jack hits part 22, which forces the jack to move up, when the nut moves to the right. By this solution, joint 1 1 does neither become larger nor wear out from the strain by lifting and letting down. Even in this case, joint 1 1 works as the real reversal link of jack 16.

In connection with all described solutions, either the jack or support is from its upper end fixed by two joint points to a suitable construction and the joint points are at a distance from one another so that the construction would turn into a sturdy supporting device.

Claims

1. A folding and adjustably mountable jack construction comprising a jack ( 1 ) , ( 16) articulated ( 11) from its upper end to turn against its base, a supporting arm (3), 15) articulated (12) from its upper end and by means of which the said jack is supported into immobile position, a turning shaft (6) including nut (9) on its worm portion (8), whereby the joint either of the said jack or the said supporting arm is arranged into the said nut, characterized in that the jack (1),(16) movement down to its position of support is arranged to work by means of moving nut (9) so that a slight axial movement of the nut releases the jack to turn down around joint (1 1), whereby also supporting arm (3), (15) is released due to its joint ( 12) to turn down into contact with said jack, and that there are between supporting arm and jack several mutual locking points, most suitably arranged by cogging (2).

2. A jack construction according to claim 1 characterized in that the jack ( 16) is articulated in nut (9) and that the fixed projection part (18) of the device frame (14) works as an element turning the jack up.

3. A jack construction according to claim 1 characterized in that supporting arm (3) is articulated in nut (9) and that the nut (9) works as an element turning jack (1 ) up.

4. A jack construction according to claim 1 and 2 characterized in that the axial movement (s) of shaft (6) releases supporting arm (15) to turn down and the opposite movement to lift it up.

5. A jack construction according to claim 1 and 3 characterized in that jack ( 1 ) down operation releases supporting arm (3) to move down into contact and locking with the jack and that jack (1) also lifts the supporting arm up.