FR2736573A1 - Apparatus for driving ratchet spanner - Google Patents

Abstract

The apparatus comprises a brace (13) extending along the spanner up to the element forming the bridging piece (14). The brace has a profiled shape (13b) to receive a ratchet spanner (15). An elastic recall device (16) is arranged within the brace to ease handling of the spanner. The recall device consist of a spring and has a U-shape, with protruding parts resting on the side of the ratchet.

Description

DEVICE FOR DRIVING A RATCHET KEY
The invention relates to a device for driving a ratchet wrench used in particular as a tool for tightening and / or loosening assembly means of the screw, nut or similar type.

 The invention relates to the technical sector of hand tools, and in particular tightening or loosening wrenches by pawls of fixing and assembly means of the screw-nut type.

 It is known to produce ratchet keys shown for example in Figures 1 and 2 of the drawings. These keys may have at one or at their two ends an eye intended for the engagement of the key on the means to tighten or loosen.

 In known manner, the key referenced as a whole by (1) comprises two plates (2) established according to the shape of the key to be obtained and are arranged parallel to each other, with a connecting spacer (4) established in the middle part of the key, the assembly being held by a couple of two riveted pins (3).

 According to the prior art, at the end or ends of the key, between the plates, there is provided a ratchet (5) having internally hollow or raised shapes (5a) capable of corresponding to the part to be moved. Externally, said ratchet has teeth (5b) oriented in one direction on its periphery. A pawl (6) integral and articulated with the lever through its plates, is arranged opposite the ratchet, this pawl having, offset, a serrated shape (6a) to cooperate with the teeth of the ratchet. Said pawl is articulated on a riveted axis (7) between the plates. An elastic blade (8) forming a spring is advantageously arranged to come into elastic abutment by a first end (8a) on the external part (6b) of the spout of the pawl, on the one hand, and by its other end (8b) in an anchor point (4a) formed in the spacer (4) connecting between the plates, on the other hand.

 There is shown in Figure la, i b and i c such an arrangement.

 FIG. 2 represents another arrangement of the pawl and of the return spring having an analogy with the preceding example, the difference residing essentially in the mode of anchoring of the spring in the connecting spacer.

 Such a ratchet design is well known and used by many manufacturers. However, its manufacturing cost is high and its assembly time significant if only by the numerous positioning of rivets, four in this case, if the key receives a ratchet at each of its ends. Furthermore, the ratchet is not protected from dirt or detritus that can become encrusted in the existing space, and interfere with the operation of the key.

 The aim sought after according to the invention was to design a new drive device for a ratchet wrench, of simple design, inexpensive to manufacture and which drastically limits the number of rivets used, while offering better protection of components to the external environment.

 These and other objects will become apparent from the following description.

 According to a first characteristic, the device for driving a ratchet key, the key being of the type comprising two plates profiled according to the shapes of the key to be obtained and the end or ends of which being arranged with an eye in sight receiving at least one ratchet to ensure the tightening or loosening of a means, a spacer being disposed between the plates, the assembly being held by riveted pins, is remarkable in that said spacer is established on a very great length of the key to come substantially opposite the ratchet part, the end or ends of the spacer being arranged with a profiled cut forming a housing for receiving a pawl and an elastic return means of said pawl, said pawl being mounted free in movement and articulation in the aforementioned housing to come to cooperate with the teeth of the ratchet during the manipulation of the key.

 These characteristics and others will become apparent from the following description.

To fix the object of the invention illustrated without limitation to the figures of the drawings where
Figure la is a top view of a ratchet wrench according to the prior art.

 Figure i b is a side view in section of the key according to Figure la.

 Figure i c is a plan view of the key according to Figure la, the upper plate having been removed.

 Figure 2 is a view of another embodiment according to the prior art.

 Figure 3 is a view of a ratchet wrench according to the invention.

 Figure 4 is a view in the disassembled position of the ratchet and its various components.

Figure 5 is a longitudinal sectional view according to Figure 3
In order to make the object of the invention more concrete, it is now described in a nonlimiting manner in the figures of the drawings.

 The ratchet wrench according to the invention is referenced as a whole by (10). It comprises two plates (11 - 12) established and profiled according to the shapes of the key to be obtained and they constitute the visible faces of the key. The end (s) of the key can be arranged with the means of the invention by forming an eye under the conditions well known from the prior art.

 According to the invention, the spacer (13) which separates the two plates is established over a very long length, to come substantially opposite the ratchet part (14) disposed at the end of the key. The end (s) (1 3a) of the spacer is / are fitted (s) with a profiled cutout (1 3b) forming a housing for receiving the pawl (15) and an elastic return means (16) of said pawl. More specifically, said cutout (13b) comprises, at its bottom, a first groove shape (13c) forming a retaining end (1 5a) which is rounded by the pawl (15) in order to ensure free movement and articulation of it according to a certain angular sector. The front end (1 5b) of the pawl is arranged with a notched shape to cooperate with the teeth of the ratchet. The elastic return means (16) is of the pin spring type and has a U shape. Its bottom (16a) is inserted into a second housing (13d) formed in the cutout (1 3b) of the spacer while one (1 6b) of its free branches bears on the head (1 5c) of the pawl, and the other branch (1 6c) is centered in the housing (1 3d) and inserted while being held against the wall (1 3) facing the cutout of the spacer. A retaining spout (1 3h) ensures the holding of the return means (16).

 Thus, by this arrangement, it is no longer necessary to use rivets to ensure the articulation and pivoting of the pawls. A maximum of two rivets (17) are established in a known manner to ensure the connection between the plates and the spacer. Each spring (16) and each pawl (15) is perfectly held in position and cannot be released by the assembly carried out. The edges (1 3f) of the end of the spacer form lips and come opposite the teeth of the ratchet without touching them, allowing the rotation of the latter. However, the existing interval (i) is not sufficient to allow the escape of either the pawl or the return means.

 In its middle part, the spacer may have lightening zones (13g) established in any suitable manner.

 The ratchet wrench according to the invention is therefore particularly advantageous in the simplicity of manufacture and assembly, resulting in a substantially reduced cost price compared to the keys manufactured according to the prior art mentioned above.

 In addition, better protection of the pawl and of the associated return spring is obtained, in particular with respect to the external environment. The key obtained is more robust. The ratchet teeth are straight and the key can be used in any position.

Claims (6)

CLAIMS The assembly being held by riveted pins (17), characterized in that said spacer (13) is established over a very long length of the key so as to come substantially opposite the part forming a ratchet, the end or ends (13a ) of the spacer being arranged (s) with a profiled cutout (1 3b) forming a housing for receiving a pawl (15) and an elastic return means (16) of said pawl, said pawl being mounted free in movement and articulation in the aforementioned housing to come cooperate with the teeth of the ratchet when handling the key. -1- Device for driving a ratchet wrench, the key being of the type comprising two profiled plates (1 1 - 12) according to the shapes of the key to be obtained and the end or ends of which being arranged with a eye for the reception of at least one ratchet (14) to ensure the tightening or loosening of a means, a spacer being disposed between the plates, -2- Drive device according to claim 1, characterized in that the cutout (s) (1 3b) formed (s) at the or at the ends of the spacer are arranged with a groove shape (13c) forming retaining 'a profiled end (1 Sa) of the pawl in order to ensure a clearance and a free articulation according to an angular sector, and in that the elastic return means (16) is of the U-shaped spring and pin type, of which the bottom (1 6a) in the bottom of the cutout (i 3b), one of the branches (1 6b) of the spring bearing on the head (1 5c) of the pawl, and the other branch (16c) being support against the facing wall (1 3) of the cutout. -3- Drive device according to claim 2, characterized in that the return means (16) is centered in its bottom part in a second housing (1 3d) formed in the cutout, and in that a spout retainer (1 3h) is established at the end of the wall (1 3h) to maintain the spring.  4- Drive device according to any one of claims 1, 2 and 3, characterized in that the end edges (1 3f) of the spacer form lips and come opposite the teeth of the ratchet, without touching them , by defining an interval (i) insufficient to allow the escape of the pawl of the return means. -5- Drive device according to any one of claims 1, 2, 3 and 4, characterized in that two riveted axes (17) only ensure the assembly of all the components of the key, these axes being independent of the pawls, said pawls not being articulated with respect to an added axis. -6- Drive device according to any one of claims 1 to 6, characterized in that the ratchets have a straight and non-oriented toothing cooperating with the end forming spout (15b) of the pawl, and allowing reversibility of use of the key.