[0001] The present invention relates to a ratchet lever for actuating a car lifting jack.
[0002] At present there are known ratchet spanners used for tightening bolts and nuts. Ratchet
spanners generally have an elongate portion serving as a handle and an enlarged head
portion comprising a toothed wheel co-operating with a ratchet which allows the wheel
to rotate in one direction of rotation, whilst it impedes rotation in the opposite
direction. The toothed wheel has a central opening of polygonal shape in which there
is to be inserted the bolt to screw or unscrew. As the toothed wheel must further
be secured in rotatable manner to the spanner housing, on the opposite sides of the
wheel there must be formed guiding means of circular shape, such as reliefs or grooves
co-operating with corresponding apertures or reliefs formed in the spanner housing.
[0003] In order to apply a final tightening torque, ratchet spanners have to be able to
withstand considerably high torques. Consequently, the mechanisms (toothed wheel and
ratchet) are made out of turned steel, and therefore involve high manufacturing costs
owing to the turning processing of the mechanism elements.
[0004] It is an object of the present invention to provide a ratchet lever of low cost,
adapted to be applied to a car jack to lift a car quickly and safely through the conventional
quick and repetitive movement by which ratchet spanners are used. Particularly, it
is a significant object of the present invention to provide a ratchet lever that does
not require costly housings and metal mechanisms obtained by turning as those exploited
by conventional ratchet spanners.
[0005] These and other objects are achieved by a ratchet lever as defined in appended claim
1. Advantageous embodiments of the invention are defined in the dependent claims.
[0006] These and other objects, advantages and features of the present invention will become
readily apparent to those skilled in the art from a study of the following description
of a few exemplary preferred embodiments when read in conjunction with the attached
drawings and appended claims.
- FIG. 1
- is a perspective view, to an enlarged scale, of a ratchet lever according to the present
invention, in which there are visible the inner parts;
- FIG. 2
- is a perspective view of the lever of FIG. 1 once assembled;
- FIG. 3
- is a perspective view of a toothed wheel being part of the ratchet mechanism;
- FIG. 4
- shows the elements forming the toothed wheel of FIG. 3;
- FIGS. 5, 7 and 9
- are perspective views, to an enlarged scale, of a few alternative embodiments of the
toothed wheel utilised in the lever of the present invention;
- FIGS. 6, 8 and 10
- are cross sectional views as seen according to lines C-C, B-B, and A-A, respectively,
of FIGS. 5, 7 and 9;
- FIGS. 11 and 12
- are two side views showing a particular embodiment of the lever according to this
invention in two different operational positions;
- FIG. 13
- is a view of the lever of this invention in a further embodiment;
- FIG. 14
- shows an embodiment of the housing or containing shell of the lever different from
those of the preceding drawings; and
- FIGS. 15 to 18
- are views showing exemplary ways for closing the half-shells of the lever housing.
[0007] Referring initially to Figure 1, numerals 1 and 2 designate two complementary half-shells
made of plastic or thin plate and constituting the outer body or housing of a lever.
One of the two half-shells, designated at 1, is for containing the inner parts of
the lever, whilst the other half-shell, designated at 2, acts as a cover. The outer
body of the lever forms an enlarged head portion 10 containing the gears and an elongated
portion 11, preferably of tubular shape, for hand gripping or for insertion of a handle,
as described herein after.
[0008] The half-shells 1 and 2 may be separate, as shown in FIG. 1, or joined by means of
a junction 30, as shown in FIG. 14.
[0009] A seaming 31, as shown in FIG. 15 may be used to couple and close together the separate
or joined half-shells 1 and 2. Alternatively, a riveting 32 may be used as shown in
FIG. 16, or a spot-welding 33 as shown in FIG. 17, or still a snap-fit coupling 34
could be adopted, as depicted in FIG. 18. FIG. 15 is a cross sectional view taken
along the line A-A of FIG. 13, whilst FIGS. 16 to 18 are simply schematical views
of the closing of the half-shells.
[0010] Within the head portion 10 of half-shell 1 there is fitted a toothed wheel 5 engaging
a ratchet 3 with a returning spring 4. The ratchet 3 allows the wheel to move in the
direction indicated by arrow A and hinders its movement in the opposite direction
of rotation.
[0011] As shown in FIGS. 3 and 4, the toothed wheel 5 forms a central opening 6 of polygonal
or rectangular shape for insertion of a rotatable element (not shown) such as a worm
screw that drives the lifting operation of a car jack. Fitted to the opposite sides
of the wheel are disc elements 7 and 8 having central openings 6 equal to those formed
in the wheel 5. Disc elements 7 and 8 are integral with the wheel 5 and project from
the sides of the wheel to be rotatably inserted in circular bores 9 formed in the
head portion 10 of half-shells 1 and 2 (FIGS. 1 and 2).
[0012] According to the present invention, the mechanisms of the ratchet lever are made
of steel or any other suitable metal material. In any case, the choice of the material
employed will fall on a pressed material possessing mechanical characteristics such
as to undergo little deformation when subjected to normal operation stresses, which
are particularly more intense in the zones of apertures 6 and on the peripheral teeth
of the wheel 5.
[0013] Referring to FIGS. 5 and 6, according to a first embodiment of this invention, the
toothed wheel 5 and opposite disc elements 7, 8 are distinct bodies formed by separate
pressing operations. Only in a second time, the two disc elements are welded to the
opposite sides of the toothed wheel 5 along respective indentations 20 and 21. In
this embodiment, the toothed wheel can be made of a first material, and the disc elements
of a different material.
[0014] In another embodiment, not shown, the toothed wheel can be pressed in a single piece
incorporating the disc elements.
[0015] Referring to FIGS. 7 and 8, in accordance with a further embodiment of this invention,
the toothed wheel 5 is made by pressing two specular and complementary elements 5a
and 5b, welded by indentations 20 along the facing sides. In this variant, the two
opposite sides of the two elements 5a, 5b each have an annular relief 12 around the
polygonal opening 6 in which there is engaged the rotatable element of the car jack
to be rotated. The annular relief 12 carries out the same function as the disc elements
discussed with reference to FIGS. 5 and 6 and is adapted to engage the bores 9 of
the half-shells 1 and 2 constituting the lever housing.
[0016] In FIGS. 9 and 10 there is shown a still further variant, according to which the
toothed wheel 5 is once again made by welding two specular, complementary elements
5a, 5b, but forming a central circular relief 13 at the centre of which there is formed
the polygonal opening 6. Also in this case, the functions of the previously discussed
disc elements are carried out by elements incorporated in the toothed wheel. The central
reliefs 13 insert in rotatable and guided manner in bores 9 of the lever housing.
[0017] Still according to the present invention, advantageously also the ratchet 3 may be
made out of pressed metal.
[0018] Referring to FIGS. 11 and 12, in the opening of the tubular elongated portion 11
of the housing there can be releasably inserted a handle 14 prolonging the lever arm.
The handle may be of the kind which the vehicle is already equipped with, and so having
an end head 15 with a hexagonal seat 16 for unscrewing the vehicle wheel bolts. In
the embodiment illustrated in FIGS. 11 and 12, the handle 14 advantageously forms
a throw 17 near its end portion and is rotatably inserted in the housing tubular portion
11 to alternately reach a horizontal position (FIG. 11) for quick movement and an
upright, rotated position (FIG. 12) for the car lifting movement.
[0019] It will be appreciated that the manufacturing of the gears constituting the ratchet
mechanisms by pressing of metal allows for considerable savings with respect to conventional
turning of steel. The ratchet lever of the present invention, unlike ratchet spanners,
is not made for applying high tightening torques, but only for transmitting a rotary
movement under to a substantially constant torque in lifting a car. A plastic material
could also suffice to withstand the stresses to which the ratchet mechanism is subjected
to when lifting a car.
[0020] There has been described hereinabove a few exemplary preferred embodiments of the
ratchet lever according to the principles of the present invention. Those skilled
in the art may now make numerous uses of, and departures from, the above described
embodiments without departing from the inventive concepts disclosed herein, for example
concerning the materials to be employed, constructional and operational details.
1. An actuating lever for a car jack having a rotating element driving the lifting movement
of the car, characterised in that the lever comprises a ratchet mechanism with a toothed
wheel (5) with a central polygonal opening (6) for insertion of said rotating jack
element, and wherein at least the toothed wheel is made of a pressed metal material,
the ratchet mechanism being contained within a housing constituted by two half-shells
(1, 2) made of plastic or thin plate.
2. A lever as claimed in claim 1, characterised in that each opposite side of the wheel
(5) is provided with a disc element (7, 8) integral to said wheel and projecting from
the sides of the wheel for being inserted in corresponding circular bores (9) formed
in the lever housing (1, 2) containing the ratchet mechanism.
3. A lever as claimed in claim 2, characterised in that the toothed wheel (5) and the
opposite disc elements (7, 8) are distinct bodies of metallic material obtained from
separate pressing operations and joined by welding (10, 11).
4. A lever as claimed in claim 2, characterised in that said toothed wheel (5) is pressed
in a single piece incorporating said disc elements (7, 8).
5. A lever as claimed in claim 2, characterised in that the toothed wheel (5) is made
by pressing two specular and complementary elements (5a, 5b) welded by an indentation
(20) along the facing sides, each element (5a, 5b) having an annular relief (12) of
a diameter corresponding to that of said bores (9).
6. A lever as claimed in claim 2, characterised in that the toothed wheel (5) is made
by pressing two specular and complementary elements (5a, 5b) welded by indentations
(20) along the facing sides, each element (5a, 5b) having a circular relief (13) of
a diameter corresponding to that of said bores (9).
7. A lever as claimed in claim 1, characterised in that also the ratchet (3) of said
mechanism is made of pressed metal material.
8. A lever as claimed in claim 2, characterised in that the lever housing forms a tubular
portion (11) allowing insertion therein of an extension handle (14).
9. A lever as claimed in claim 8, characterised in that said handle (14) has an end head
(15) with a hexagonal seat (15) for unscrewing the bolts of a vehicle wheel.
10. A lever as claimed in claim 9, characterised in that said handle (14) forms a throw
(17) proximate to said end head (15).
11. A lever as claimed in claim 10, characterised in that said handle (14) is rotatably
inserted in the tubular portion (11) of the lever housing to alternately reach a horizontal
position for quick movement and a rotated, upright position for the car lifting movement.
12. A lever as claimed in any of the claims 8 to 11, characterised in that said handle
(14) is that which a vehicle is normally equipped with for screwing and unscrewing
the wheel bolts.
13. A lever as claimed in claim 1, characterised in that the two half-shells (1, 2) are
separate.
14. A lever as claimed in claim 1, characterised in that the two half-shells are joined
one to the other (30).
15. A lever as claimed in claim 13 or 14, characterised in that the half-shells (1, 2)
are joined therebetween by seaming (31), riveting (32), spot-welding (33), or snap
fitting (34).