GB2374589A

GB2374589A - Jack with height adaptors

Info

Publication number: GB2374589A
Application number: GB0109436A
Authority: GB
Inventors: Michael Hung
Original assignee: Shinn Fu Corp
Current assignee: Shinn Fu Corp
Priority date: 2001-04-17
Filing date: 2001-04-17
Publication date: 2002-10-23
Also published as: GB0109436D0

Abstract

A jack 10 with a lifting arm 20 has a primary load engaging disc 1 attached, the centre of which is hollow 11. At least one auxiliary load engaging disc 2 is provided, the lower cylinder 22 of which fits into the hollow of the primary disc. The different discs will have different lengths. With an auxiliary disc fitted the starting height of the lift is raised so reducing the upward movement of the lifting arm. The upper surface 12 of the primary disc may have a wave-like edge.

Description

JACK WITH A CHANGEABLE AUXILIARY DISK having a The present invention relates to a jack lifting arm with a

changeable auxiliary disk. The primary disk of the jack lifting arm is formed with an annular groove which can be connected with an auxiliary disk of a selected height so that the front travelling length of the jack without carrying any object is reduced.

The conventional jacks (including jacks of a lying type, a stand type, a scissors type or other types) has a lifting arm 20 for lifting heavy object. The front end of the prior art jack lifting arm 20 is integrally formed or firmly secured with a top disk 30 which can contact a heavy object and then lift the object. In fact, as a jack is operated, since the position of the heavy object and the top disk of the jack has level difference, before contacting with the heavy object, a distance is existed between the top disk and the heavy object, so that the front travelling length of the jack dose not carry any object. However, in this length, the user remains to operate a joystick 40 or tread a pedal so that the lifting arm 20 lifts gradually- After contacting with the object, the work of lifting heavy object is executed.

It would be desirable to be able to provide a jack lifting arm with a changeable auxiliary disk. The primary disk of the jack lifting arm is formed with an annular groove. At least one auxiliary disks are formed for being selected freely by the primary disk. Thereby, the height of the top disk of the jack lifting arm is changeable as desired. Therefore, as the jack is used to lift a heavy object. The primary disk may be connected with the auxiliary disk so

that the front travelling length in the jack without carrying any object is reduced.

The present invention will be more readily understood from the following detailed description when read in conjunction with the appended drawings of which: Fig. 1 is a perspective view of a conventional lying type jack.

Fig. 2 is a perspective view showing that the jack lifting arm is installed with a primary disk.

Fig. 3 is an exploded perspective view of the primary disk and an auxiliary disk of the present invention.

Fig. 4 is an assembly perspective view of the primary disk and the auxiliary disk of the present invention.

Fig. 5 is an assembled cross sectional view of the primary disk and auxiliary disk of the present invention.

Fig. 6 IS an assembled schematic view showing that in the present invention, different auxiliary disks are selected.

With reference to Figs. 2 and 3, the jack lifting arm with a . changeable auxiliary disk of the present invention is illustrated. The

present invention may be used to jacks 10 of lying type, stand type, scissors type or other types. Especially, a front end of the lifting arm 20 is installed with a primary disk 1. Thereby, the height of the primary disk 1 of the lifting arm 20 is changeable. The lifting arm 20 has the following components.

A primary disk 1 is integrally formed or firmly secured to a front end of the lifting arm 20 of the jack. The primary disk has a hollow annular groove 11. The upper end of the peripheral wall is formed with a disk surface 12 with wave-like edge. In general, the surface can be provided to support heavy object.

At least one auxiliary disk 2 is installed. Different auxiliary disks 2 have different forms. Various auxiliary disks 2 must have different heights for matching the primary disk 1. The auxiliary disk 2 has an upper disk surface 21 and a lower cylinder 22. The lower cylinder 22 is exactly planted into the hollow annular groove 11 of the primary disk and thus is steadily combined therein (referring to Fig. 4 and 5).

By the construction of the primary disk 1 and the auxiliary disks 2, the annular primary disk 1 may select auxiliary disks 2 and 2'of different heights and then the two are combined (referring to Fig. 6).

The height of the primary disk 1 of the lifting arm 20 may be changed as desired so that as the jack lifts an object; it may be connected with the auxiliary disk 2 according to the position of the heavy object and the level difference of the disks of the jack so as to reduce the front travelling length in the jack without carrying any object. Therefore, it may access to a heavy object conveniently for lifting the object easily.

The user is unnecessary to lift the object by manually operating a joystick 40 or treading a pedal. In the present invention, the auxiliary disk 2 and the heavy object may contact with one another rapidly In summary, in the present invention, the primary disk with a hollow annular groove is matched to the auxiliary disk with a selected height so that the front travelling length in the jack without carrying

any object is reduced. s.

Claims

1. A jack comprising a lifting arm carrying a primary disk for engaging an object to be lifted, the primary disk having a hollow interior, and one or more auxiliary disks shaped to be received in the hollow interior of the primary disk to project upwardly therefrom.