Adjustable spanner

An adjustable spanner is provided. The adjustable spanner may comprise a pair of jaw arms, co-operating to move relative to one another, the co-operating jaw arms are each provided at their ends with a jaw, wherein two adjacent jaws constitute a spanner head; a housing for receiving the co-operating jaw arms, the co-operating jaw arms slide longitudinally relative to the housing for setting pre-selected discrete standard fastener sizes, wherein the jaw arms are substantially identical, and are received in the housing being rotated 180° relative to one another about their longitudinal axis.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is the U.S. National Phase of International Application No. PCT/NL2012/000020, filed Mar. 7, 2012, designating the U.S. and published as WO 2012/121588 on Sep. 13, 2012 which claims the benefit of Dutch Patent Application No. 1038646 filed Mar. 8, 2011.

BACKGROUND

The Field of Invention

The invention relates to an adjustable spanner comprising:a pair of jaw arms, co-operating to move relative to one another, the co-operating jaw arms are each provided at their ends with a jaw, wherein two adjacent jaws constitute a spanner head,a housing for receiving the co-operating jaw arms, wherein the ends of the jaws extend outside the housing,the co-operating jaw arms slide longitudinally relative to the housing, thereby mutually tilting the jaw arms relative to one other due to the sliding, so that the jaws of the spanner head of the co-operating jaw arms move in opposite transverse direction relative to one other.

Description of the Related Art

This adjustable spanner is a constructive advantageous variant on the famous ‘English key’ or adjustable angle-head wrench. The screw adjusted spanner, by means of a worm gear, has a size-adjustable jaw width and can therefore, within certain limits, be adjusted to any size hex or square fastener head, nut or bolt, so that there is no need to have standby a large amount of fixed spanners or socket wrenches for a range of different fastener head sizes.

The adjustable spanner, however, has the disadvantage that it is difficult to accurately set the correct desired fit-size of the fastener head. Furthermore when the screw mechanism is worn out the set head size may wander off when exerting a torque force. With an improperly set jaw size the bolt or nut head may be damaged irreparably.

SUMMARY

With the adjustable spanner type according to the invention the spanner head may be easily adjusted into pre-selected discrete standard fastener head sizes by moving a pair of jaw arms.

DETAILED DESCRIPTION OF CERTAIN ILLUSTRATIVE EMBODIMENTS

Such an adjustable spanner is known from British patent application nr. 2196888. This known adjustable spanner consists of two co-operating jaw arms in a housing, which jaw arms by means of a slide member, provided with teeth, can be moved or reciprocated in the housing so as to adjust both spanner heads and also to be able to select a standard fastener head size.

This construction, however, is complicated and requires the use of many different parts; in addition, the two jaw arms are each other's mirror image and must therefore each be manufactured separately. The jaw arms each are supported by specially shaped hardened guides at each end of the housing, thereby rendering the manufacture of this adjustable spanner time consuming and costly. Moreover, adjusting the spanner heads is difficult and cumbersome.

Object of the invention is therefore to provide for an adjustable spanner, without the above-mentioned disadvantages, which is simple and can be easily manufactured from a small number of parts, which can be easily assembled, which remains firmly locked in a selected fastener head size, which does not require a slide member with teeth, and which does not require costly and complicated guides for each jaw arm on each end of the housing.

These objects of the invention are achieved by an adjustable spanner as described in the preamble wherein the jaw arms are substantially identical and are received in the housing being rotated 180° relative to one another about their longitudinal axis.

By applying two identical jaw arms it is not necessary to manufacture this essential part of the spanner—the jaw arm, by which the momentum force is exerted on the heads of the nuts and the bolts—in two mutually different versions, thereby realizing large savings on time and costs.

A special embodiment is characterized in that the jaw arm comprises a central portion and two jaws, wherein the central portion of the jaw arm is provided with a guide slot and a cam.

Preferably the guide slot is substantially transverse-oriented and the cam is provided substantially in line with the guide slot.

In particular the cams are inserted into the guide slots of the adjacent jaw arm, in the co-operative position of the pair of jaw arms, thereby forming the pivot point of the mutual tilting movement.

The pivot point of the co-operating jaw arms is formed with the above measures, by using two equal jaw arms without needing additional parts and by providing each arm with a cam and a guide slot at the side of the central portion having the thickened jaws.

In an alternative advantageous embodiment the jaw arm comprises a central portion and two jaws, wherein the jaws are provided with a greater thickness than the central portion, preferably the jaws are about twice as thick as the central portion.

As a result, at both ends of the adjustable spanner by the thickened jaws on the jaw arms, a spanner head is formed, between which a hexagonal or square nut or bolt head may be clamped in order to be able to exert a rotational torque moment on them.

In an advantageous embodiment the thickened jaws comprise a jump or step in thickness; preferably steps in thickness are provided at both ends on the same side of the jaw arm.

By providing the steps in thickness on the same side of the jaw arm and by providing the other side with an substantially flat surface, it is possible by rotating one jaw arm about its longitudinal axis, to form two adjustable spanner heads with two identical jaw arms.

In particular the angle of the step in thickness, between the jaw and the longitudinal axis, is about the same but opposite magnitude, as the angle between the lower longitudinal edge or the upper longitudinal edge respectively and the longitudinal axis.

As a result, in the closed position of the spanner head, a recess for a hexagonal nut is exactly formed because the longitudinal edges exactly abut against the step of the jaw of the other jaw arm.

The embodiment is preferred wherein the jaw arm at its upper longitudinal edge and its bottom longitudinal edge is provided with a spring fastening means; preferably the spring fastening means is a recess.

In particular the pivot point divides the jaw arm into two arm portions, wherein the spring fastening means are provided on different arm portions.

By providing the spring fastening means on both sides of the pivot point, the two jaw arms are provided with a pre-load bias tension, so that without having to use a sliding member, the jaw arms can be locked in the housing or can be unlocked and subsequently moved and adjusted.

Advantageous is the embodiment wherein a pair of tension springs are provided, wherein in the co-operative position of the pair of jaw arms, the two tension springs are connected to the spring fastening means located at the top or bottom longitudinal edges of the two jaw arms.

In particular the tension spring is a leaf spring wherein the ends are provided with connection elements, preferably the leaf spring is provided with a step corresponding to the distance between the longitudinal edges of the pair of jaw arms in co-operative position.

With two tension springs, each provided at the upper side and at the bottom side in the housing, each engaging on both jaw arms, the co-operating jaw arms each are provided with a pre-tension. The pre-tension is directed towards moving the two jaw arms away from each other about the pivot point, so that the jaws are biased against the housing. Because the springs engage on the arm parts of each jaw arm, a step is provided in the leaf springs, wherein the dimension of the step corresponds to the distance between the two jaw arms.

It is desirable for an effective use that the shoulders of the two jaws of the jaw arm are provided with teeth; preferably the teeth are formed in the thickened jaw, and comprise a row of concave-shaped recesses.

Preferably the housing at both ends is provided with an opening for the jaw arms, wherein the inner edges of the openings, located opposite the longitudinal sides of the jaw arms, are provided with a shape corresponding to the teeth on the shoulders of the jaw, preferably they are convex-shaped, so that an inner edge can engage in the recesses of the teeth, and lock the jaw arms.

In particular the ends of the top and bottom walls of the housing are flanged to form the inner edges of the opening.

With these measures a simple, inexpensive and very effective adjusting mechanism with interlocking is obtained. The shoulders of the jaws of the jaw arms are provided with teeth, which co-operate with the inner edge of the openings of the housing. Due to the applied pre-tension by means of the springs, these teeth on the shoulders are clamped against the inside edge, so that the jaw arms are locked in the openings of the housing. The jaw arms may subsequently be released by moving them towards each other against the spring pre-tension, so that the jaw arms in the housing can be slid and shifted, and a different fastener size can be selected. By providing the recesses and the inner edges with an equal, but opposite, shape, the inner edge of the housing fits exactly into the recess of the jaw arm and a good interlocking is obtained. It has been found that with concave-shaped recesses and with convex-shaped inner edges a good, reliable and wear-resistant locking is obtained.

By folding the edges of the top and/or bottom walls of the housing at their ends, advantageously in a simple manner, the interlocking can be formed without any additional parts being necessary.

The invention also relates to an adjustable spanner comprising:a pair of jaw arms, co-operating to move relative to one another, the co-operating jaw arms are each provided at their ends with a jaw, wherein two adjacent jaws constitute a spanner head,a housing for receiving the co-operating jaw arms, wherein the ends of the jaws extend outside the housing,
the co-operating jaw arms slide longitudinally relative to the housing, thereby mutually tilting the jaw arms relative to one other due to the sliding, so that the jaws of the spanner head of the co-operating jaw arms move in opposite transverse direction relative to one other, andwherein the shoulders of the two jaws of the jaw arm are provided with teeth.

The invention also relates to an adjustable spanner comprising:a pair of jaw arms, co-operating to move relative to one another, the co-operating jaw arms are each provided at their ends with a jaw, wherein two adjacent jaws constitute a spanner head,a housing for receiving the co-operating jaw arms, wherein the ends of the jaws extend outside the housing,
the co-operating jaw arms slide longitudinally relative to the housing, thereby mutually tilting the jaw arms relative to one other due to the sliding, so that the jaws of the spanner head of the co-operating jaw arms move in opposite transverse direction relative to one other, andwherein the jaw arm at its upper longitudinal edge and its bottom longitudinal edge is provided with a spring fastening means, andwherein a pair of tension springs is provided, wherein in the co-operative position of the pair of jaw arms, the two tension springs are connected to the spring fastening means at the top or bottom longitudinal edges of the two jaw arms.

FIG. 1shows the adjustable spanner1according to the invention with the housing9and the jaw arms2,3arranged therein. At the ends of front jaw arm3—in the drawing—are provided right jaw4and left jaw7, and at the ends of the rear jaw arm2are provided jaws6and5. Left-hand jaws5,7and right-hand jaws4,6form at each end an adjustable spanner head8which can be positioned on the nut and bolt heads in order to rotate the nut and/or bolt head. By longitudinally sliding and shifting the pair of jaw arms relative to the housing9, a different standard spanner size can be set, such as for example, six different sizes at each end with 6-11 mm at the right-hand end in the drawing and from 12 to 17 mm at the left-hand end.

InFIG. 2Aa partially cut away and transparent adjustable spanner is shown with rear jaw arm2and superimposed front jaw arm3. The pair of jaw arms is fully shifted to the right so that the left-hand spanner head8is closed and the right-hand spanner head is fully opened so that, for instance, left a size of 12 mm is selected, and right a size of 11 mm.

FIG. 2Bshows a bottom view of the adjustable spanner with housing9and spanner head8. By means of the dotted lines can be seen that the two jaw arms2,3abut against each other, in which left-hand jaw7of jaw arm3is positioned on the left-hand side at the bottom side and the right-hand jaw6of jaw arm2is positioned on the right-hand side at the bottom side.

FIG. 3Ashows the elongate jaw arm2according to the invention, which also can be used as second jaw arm3by rotating about its longitudinal axis. The jaw arm2comprises a flat centre portion10and two jaws5,6at its ends. Upper longitudinal edge17is in this embodiment the flat upper side of the central portion10of the jaw arm2having a width equal to the thickness of the central portion10. Bottom longitudinal edge16is the flat bottom side of the central portion10. The jaws5,6are formed thickened, transforming with a step in thickness11,12into in the centre portion10. The thickened jaws are provided with a shoulder28. Furthermore, the jaw arm2is provided with a guide slot19, and a cam18. The guide slot19extends substantially in the width direction i.e. transversely oriented, and the cam18is positioned in line with the guide slot19. The width of the cam18is preferably chosen such that the cam18snugly fits into the guide slot19. As a result, the two jaw arms2,3are coupled to each other in a tilting and shifting manner.

FIG. 3Bshows in side view the jaw arm2ofFIG. 3Awith the longitudinal axis13shown in dotted lines. When the identical jaw arm3is rotated 180° around the longitudinal axis13, the two jaw arms2,3can be mutually coupled into a co-operating pair. Upper longitudinal edge17extends, at least substantially, flat and parallel to the longitudinal axis13from the shoulder28of left-hand jaw5to the right-hand jaw6. Near the right-hand jaw6the longitudinal edge17is provided with an angle15with respect to the longitudinal axis13. Bottom longitudinal edge16extends, at an angle14with the longitudinal axis13, from starting point jaw5and then parallel to the longitudinal axis13to the shoulder28of the jaw6. Both the step in thickness11of jaw5as well as the step in thickness12of jaw6, are at an angle15to the direction of the longitudinal axis13. In a preferred embodiment, angle14and angle15are approximately equal, so that—in the closed position of the spanner head concerned—the bottom longitudinal edge16abuts fittingly against the step in thickness11and the upper longitudinal edge17abuts fittingly against the step in thickness12(see alsoFIG. 4B). The longitudinal edges16,17are provided with spring fastening means20, here arranged as recesses20.

InFIG. 3Cis shown the jaw arm2ofFIG. 3A-3Bin a bottom view. It is clearly shown that the steps in thickness11and12are arranged on the same side of the jaw arm2. Projection i.e. cam18extends also on the same side, and defines, together with the guide slot19, the pivot point21of the (tilting) movement of the coupled jaw arms2,3. The pivot point21divides the jaw arm2into two arm portions22,23, in which the spring fastening means20are each provided on opposite arm portions22,23on opposite longitudinal edges16,17.

FIG. 4shows the opened housing containing the mounted jaw arms2,3, and the two tension springs24,25. The tension springs, which are shown in more detail inFIG. 8A, 8B, 8C, are connected to the spring fastening means20of the jaw arms and lay against the inner walls36of the housing, which inner walls36are shown in more detail inFIG. 9A-9E. The co-operating jaw arms2,3are fully shifted to the right with respect to the housing, so that the right-hand jaws4,6are opened, and the left-hand jaws5,7are closed. The tension springs24,25each engage the spring fastening means on the upper jaw arm2and the rear jaw arm3, and are pre-tensioned or biased by internal walls36. The tension springs24,25together exert a spring force, driving apart the co-operating, coupled, jaw arms2,3so that the jaws4-7are biased against the housing.

InFIG. 4Bis enlarged shown detail circle B ofFIG. 4with bottom longitudinal edges16and step in thickness11of the jaw arms2,3. Due to the chosen equal angles14,15(seeFIG. 3B), the step in thickness11and the bottom longitudinal edge16are closely fitting together.

InFIG. 4Ais enlarged shown detail circle A ofFIG. 4with shoulder28and the recesses30arranged thereupon to form teeth for locking.

FIG. 5and the detailedFIGS. 5A and 5Bshow the co-operating jaw arms2,3which have been fully shifted to the left with respect to the housing, so that the right-hand jaws4,6are closed and the left-hand jaws5,7are open.

InFIG. 6the position of the jaw arms2,3ofFIG. 4is shown with arc-shaped connection elements26of leaf springs24,25that engage in recesses20.

InFIG. 6Bis shown enlarged in detail how, in the closed position of the jaws5,7, cam18′ of the rear jaw arm3is slid into the bottom position in the guide slot19″ of the upper jaw arm2, while simultaneously the cam18″ of the front jaw arm2is slid into the top position of the guide slot19′ of rear jaw arm3.

InFIG. 7Bis shown enlarged detail circle B ofFIG. 7in the open position of the jaws5,7, in which the cam18′ of the lower jaw arm3is slid into the top position of the guide slot19′ of the front jaw arm2, and simultaneously the cam18″ of the front jaw arm2is slid into the bottom position of the guide slot19′ of the lower jaw arm3.

InFIG. 7AandFIG. 6Athe locking mechanism of the spanner is shown. For this purpose the shoulders28of the jaws4to7are provided with teeth29. Preferably, the teeth are formed by providing concave-shaped grooves or recesses30over the entire thickness of the jaw. At the openings of the housing, opposite the teeth, inside edges32are provided which fit into the recesses30. The inner edges32are preferably convex-shaped, but may be provided with any possible shape in accordance with the shape of the recesses in the jaws4-7. Due to the bias of the tension springs24,25all four of the corresponding recesses30on the four shoulders28, are pressed against the inside edges32, thereby locking the two jaw arms against displacement. In order to be able to select a different nut size, the opened jaws4,6or5,7are moved towards each other, thereby unlocking the jaw arms2,3.

InFIG. 8A-8Cis shown in more detail the leaf spring24,25provided at it ends with the connection elements26in the form of (semi)-circular flanged ends, which fit into the fastening means20on the jaw arms2,3. The leaf spring is provided with a step27approximately the size of the thickness of the central portion10of the jaw arm2,3, since the leaf spring must pre-tension two arm portions located on different jaw arms2,3.

InFIG. 9A-9Fan embodiment of the housing9is shown having a removable cover35. The housing is provided with openings31for the co-operating jaw arms2,3. The housing9comprises an inner wall36where upon the leaf springs are supported. The housing is further provided with a top wall33and a bottom wall34, which near the openings are flanged or even completely folded in order to form the respective inner edges32for the locking mechanism. This is an advantageous solution since no additional parts are necessary for constructing the locking mechanism.

Design alternatives and solutions for the housing may also be applied, as long as there are interior edges32provided for locking and for supporting the leaf springs.