GB2252066A - Socket extension bar with quick release locking arrangement - Google Patents

Abstract

A socket wrench extension bar has a cross-bore 16 in which balls 18, 20 are retained. One of the faces 34 of the bar has a groove 32 in which a tab 40 is received. A spring 50 inside a sleeve 44 biases the tab to the left so the tab overlies the balls. The spring force acts to rock the tab against the ball 18 to cause the other ball 20 to project from the bar end into locking engagement with a recess 38 in the socket 24. When the projecting ball 20 is pushed into the cross bore as the socket is being mounted the other ball 18 is pushed cut of the bore to raise the tab 40 so that at it is engaged by the socket end 39. This causes the tab to be moved to compress the spring 50. The tab can move with and with respect to sleeve 44. <IMAGE>

Description

22 6j SOCKET WRENCH DRIVERS HAVING A PUSH-ON, QUICK RELEASE LOCKING

ARRANGEMENT This invention relates to socket wrench drivers provided with a push-on, quick release locking arrangement of the general type disclosed in my U.S. Patents Nos. 4,589,308; 4,537,100; and 4,770,073.

The locking arrangements disclosed in these U.S. patents employ an angled cross bore (or equivalent) in which a lock member (a pair of balls or equivalent) is mounted. The angled bore is used so the ball which does not engage the slider or key will engage the socket first and ensure a given sequence in actuating the slider. This then lifts the end of the slider to butt against the socket and push the slider and the associated sleeve away from the end of the driver. If the user is holding the driver in such a way as to interfere with movement of the slider the connecting process is difficult or impossible.

In addition, these devices employ some parts which require machining, which raises the cost of manufacture.

The present invention is concerned with providing a driver with an improved locking arrangement which is easier to use and is also cheaper to manufacture.

According to the invention, there is provided a socket wrench driver provided with a push-on/quick release locking arrangement comprising, a drive end on said driver having an even number of flat drive surfaces and having an axis, a cross bore through said drive end and intersecting opposed flat surfaces, said cross bore having an axis, lock means mounted in said bore and having a length generally equal to the distance between said opposed surfaces, an axial groove in one of said opposed flat surfaces, means retaining said lock means relative to said bore while allowing limited projection of said lock means to a lock position beyond one of said opposed flat surfaces, an axially movable sleeve mounted on said driver for movement between a first position and a released position, said sleeve having an inturned front wall, control means mounted on said drive end and including a key lying in said groove and movable between a first position in which it overlies said lock means to urge said lock means to its said lock position and a release position in which it has moved away from the end of said driver to allow said lock means to retract into said cross bore, said control means also including a spring seat integral with said key and mounted on said driver end inside said sleeve adjacent said front wall, a spring mounted on said driver erid inside said sleeve and acting on said spring seat to urge said control means and said key towards said end, said control means and said key being movable with and with respect to said sleeve, said control means having enough clearance relative to said driver end and relative to said sleeve to allow rocking movement of the control means whereby the key can be r. aised by said lock means when said lock means is moved from its said lock position to its said release position.

Further according to the invention there is provided a socket wrench driver provided with a push-on/quick release locking arrangement comprising, a drive end on said driver having an even number of flat drive surfaces and having an axis, a cross bore through the drive end intersecting opposed flat surfaces, said cross bore having an axis and an end at each of said opposed flat surfaces intersected by said bore, lock means mounted in said bore having a length generally equal to the distance between said opposed surfaces, 4 - a keyway in one of said opposed flat surfaces, means retaining said lock means relative to said bore while allowing limited projection of 'the lock means to a lock position beyond said other surface, an axially movable sleeve mounted on said driver for movement between a locked position and a released position, said sleeve having an inwardly turned front wall, an annular spring seat positioned inside said sleeve adjacent said front wall of said sleeve and including a lock key in said keyway operative to obstruct movement of said lock means into said groove when the sleeve is in said locked position whereby the lock means projects from said other of said opposed flat surfaces, said key being retracted from said locked position when said sleeve is moved to its said released position whereby said key no longer obstructs said lock means and the lock means can move into said bore, and a spring mounted inside said sleeve and bearing against said spring seat to bias said sleeve to said locked position.

The locking arrangement of a driver in accordance with the invention provides for movement of the key or slider independently of the sleeve, so if the user is preventing movement of the sleeve the function of the slider is not affected and the connection of the driver to the socket can be completed. This construction is also simpler and effects a cost saving. My previous designs fixed the lock tab or key relative to the sleeve, but I now f ind it is better to provide for relative motion.

The sleeve in my previous designs is a machined part. my new design can be made with deep drawn parts or with tubing crimped to engage the driver and to provide a seat for the key assembly and the associated spring. This results in substantial savings.

In one preferred form of sleeve construction, the sleeve has an inturned front wall and a rear shoulder, and a washer is seated on the shoulder, the rear of the sleeve being crimped onto the washer to hold it on the shoulder.

This invention is also applicable to a compact driver incorporating a universal joint. This construction is novel and results in a very compact structure.

U.S. Patent No. 4,938,107, dated July 3, 1990, discloses a drive extension which is very broadly similar to the device in accordance with the invention, but it requires expensive machined parts.

6 - Various embodiments of the driver in accordance with the invention will now be described, by way of example, with reference to the accompanying drawings, in which:- Figure 1 is a longitudinal section through a first embodiment of the driver as it enters a socket; Figure 2 is a longitudinal section showing the driver engaged with the socket; Figure 3 is a longitudinal section showing the manner of disengaging the driver from the socket; Figure 4 is a transverse section through the end of the driver taken on the line 4-4 in Figure 6; Figure 5 is a perspective view of a portion of the driver; Figure 6 is a longitudinal section through a second embodiment of the driver incorporating a universal joint; Figure 7 is a top plan view of the driver shown in Figure6; Figure 8 is a transverse sectional view taken on line 8-8 in Figure 7; 7 - Figure 9 is a longitudinal section through a third embodiment of the driver which is similar to the first embodiment except for a modified sleeve construction; Figure 10 is a transverse section taken on line 10-10 in Figure 9; Figure 11 is a transverse section taken on line 11-11 in Figure 9; and Figure 12 is a perspective view of the sleeve assembly with part broken away.

The drivers shown are in the form of extensions for attachment to a wrench in a conventional manner, although it will of course be understood that the drivers in accordance with the invention may also be formed as integral parts of the wrench.

The driver 10 shown in Figures 1 to 3 has a solid round, cylindrical shaft 12 of the desired length. One end of the driver is provided with a recessed square hole 13 which may be connected to and driven by the customary wrench. The other end of the driver has a square end 14 dimensioned to fit one of the standard socket wrench sizes. Drive end 14 has a cross bore 16 in which two 8 - balls 18,20 are retained by conventional coining operations at each end of the cross bore to reduce the opening to less than the ball diameter. The axis of the cross bore is perpendicular to the axis of the driver and this is contrary to the teaching of my prior U.S. patents. I previously felt it quite important to angle the cross bore so the ball closer to the end of the driver would always engage the socket first to ensure the proper sequence of operating the control tab to allow the ball 20 to be depressed to lift the control tab 36 via ball 18 before the driver is fully inserted into the socket. I now find the bore can be perpendicular and work satisfactorily although sometimes requiring a little wiggling to free the tip of the control tab 40. A perpendicular cross bore is much less costly to make as compared to the angled bore. The angled cross bore is superior but costs more.

As viewed in the drawings, an axial groove 32 is provided in the middle of the flat drive face 34 and has a depth which, when added to the length of the cross bore measured from the bottom of the groove, is equal to the combined diameters of the two balls 18 and 20. This permits the balls to lie wholly between the two opposed flat faces when the control tab or key 40 is moved to position the lock portion 36 in an unobstructing position. When the tab is in the obstructing position shown in Figures 1 and 2 ball 20 projects to a lock position beyond the flat face 35 of the driver. When the drive end is inserted into the recess 24 of a socket the projecting ball 20 will engage an undercut 38 in the recess 24 and the lock tab will be backed up by the opposite wall of the recess to positively lock the socket on the driver. Before reaching this condition, however, ball 20 is pushed into the cross bore as the driver is pushed into the socket recess. This will cause ball 18 to raise the tab 40 and the tab will be engaged by the outer f ace 39 of the socket, thus pushing the tab to the right in Figure 1.

The tab 40 is an integral part of the control means which includes an annular spring seat 42 captured inside sleeve 44 slideably mounted on the driver. The sleeve 44 has front and rear walls 46,48 turned in to capture the coil spring 50 inside the sleeve. The right hand coil 52 of the spring is captured in a groove 54 on the driver and the left coil of the spring bears via the ring 42 against the inside of the front wall 46 of the sleeve 44. Thus, the spring 52 biases the sleeve 44 to he left until the rear wall 48 of the sleeve engages the spring coil 52 which is engaged in the groove 54 in the end of the driver and functions as a limit stop. When the lock tab 40 is pushed to the right the tab and the spring seat 42 can move to the right relative to the sleeve if necessary. Therefore, if the user is holding the sleeve in a manner to restrict movement of the sleeve (a condition which could frustrate efforts to connect my prior designs) the lock tab 40 can still be raised and pushed to the right to enable the connection to be completed easily.

Since the tab 40 and the annular spring seat 42 are integral and do not tightly engage the driver the control means (tab and spring seat) can tilt or rock upwardly when ball 18 rises under the tab 40. When the tab rises it moves up to engage the outside face 39 of the socket during the connection process. This means the applied force will act to push the tab 40 and seat 42 to the right in the drawings. Since the control means can move relative to sleeve 44 it makes no difference whether or not the sleeve is free to move. The spring acting on the seat 42 normally holds the seat 42 flat against the inside of the front wall 46 and this means the lock tab will be held down on the ball 18.

The sleeve 44 can be deep drawn by conventional means so long as the diameter is greater than the depth or length of the sleeve. This is a great cost saving over my prior designs which require machined parts. If the part is drawn, then it is assembled and the rear is coined or spun in to form the rear wall 48. If the diameter to length ratio is less than 1 then the sleeve can be made out of tubing, which is still a saving over the machined part ofmy prior designs.

Simply adding the structure of Figures 1-5 to a universal joint type driver would add too much length to the driver for it to be useful in tight spaces. This then requires another approach to provide a compact tool. The result is shown in Figures 6-8. In this arrangement the left hand portion of the driver 60 has a groove 32 receiving the lock tab 40 as with the first modification. But in this embodiment the sleeve 60 is more cylindrical and fits over the large diameter portion of the driver while the spring seats against the shoulder 64. The right portion of the driver 60 is shaped to provide two spaced ears 66,66 projecting to the right from face 80 to receive the left end of the square connector 68. Pin 70 hinges the connector to the ears and driver while pin 72 hinges the connector to the ears 74 on the driven end member 76. Thus the pins 70,72 at 90 degrees to each other define the universal joint. The sleeve 62 is retained on the driver by bending tabs 78 down alongside the ears 66 to limit motion of the sleeve to the left by engagement of the tabs with faces 80 on each side of the ears 66. The face 80 functions as a limit stop. The sleeve is still free to move to the right to move the lock tab from the blocking/locking position shown in Figure 6.

With this construction in conjunction with a universal joint the increase in length caused by incorporating the quick release feature is minimized. Bending the retaining tabs 78 down to enage the rear face 80 of the driver 60 to limit motion under influence of the spring 50 simplifies the construction.

The tapered sleeve shown in Figure 1, or an equivalent stepped sleeve configuration, is used to get a large enough diameter to allow the larger (right) end of the sleeve to be formed (rolled in) to capture the spring and engage the spring coil 52 which was captured in the groove on the shaft 12. The forming operation, however, proves to be difficult in practice and during assembly the large radial space between the sleeve and the shaft gives the spring enough room to invert itself and cease to function as a spring. Furthermore, the soft metal required to permit the deep drawing and forming of the sleeve does not provide a good wear surface of the internal diameter of the turned-in end of the sleeve on the shaft and the internal diameter is difficult to control. The construction shown in overcomes the problems.

Figures 9-12 The sleeve 144 in Figures 9-12 has a substantially uniform diameter which is more conventional in deep drawing and requires simpler, lower cost tooling. The left end 146 is turned in as with the other designs but the right end is formed to provide a shoulder 150 against which the washer 152 seats. The washer 152 is captured in that position when the right end of the sleeve is crimped over the washer as indicated at 154. The crimping is to capture the washer only and does not provide the internal diameter guiding the sleeve on the shaft 12; the washer provides that guiding function. The washer can be of hardened metal providing a superior and more accurate wear surface. The sleeve closely confines the spring and prevents the spring from inverting itself during assembly; the coils cannot get past each other in the available space so the spring cannot invert.

Various design variations are likely as the design in accordance with the invention is adapted to different types of drivers and extensions..

14 -

Claims (1)

1. A socket wrench driver provided with a push-on/quick release locking arrangement comprising, a drive end on said driver having an even number of flat drive surfaces and having an axis, a cross bore through said drive end and intersecting opposed flat surfaces, said cross bore having an axis, lock means mounted in said bore and having a length generally equal to the distance between said opposed surfaces, an axial groove in one of said opposed flat surfaces, means retaining said lock means relative to said bore while allowing limited projection of said lock means to a lock position beyond one of said opposed flat surfaces, an axially movable sleeve mounted on said driver for movement between a first position and a released position, said sleeve having an inturned front wall, control means mounted on said drive end and including a key lying in said groove and movable between a first position in which it overlies said lock means to urge said lock means to its said lock position and a release position in which it has moved away from the end of said driver to allow said lock means to retract into said cross bore, - is said control means also including a spring seat integral with said key and mounted on said driver end inside said sleeve adjacent said front wall, a spring mounted on said driver end inside said sleeve and acting on said spring seat to urge said control means and said key towards said end, said control means and said key being movable with and with respect to said sleeve, said control means having enough clearance relative to said driver end and relative to said sleeve to allow rocking movement of the control means whereby the key can be raised by said lock means when said lock means is moved from its said lock position to its said release position.

2. A socket wrench driver according to claim 1 in which said spring seat is a generally annular member and said key projects forwardly therefrom towards the end of said driver, and said spring is a compression spring coiled around said drive end and acts against the drive end and said spring seat.

A socket wrench driver provided with a push-on/quick release locking arrangement comprising, a drive end on said driver having an even number of flat drive surfaces and having an axis, a cross bore through the drive end intersecting opposed flat surfaces, said cross bore having an axis and an end at each of said opposed flat surfaces intersected by said bore, lock means mounted in said bore having a length generally equal to the distance between said opposed surfaces, a keyway in one of said opposed flat surfaces, means retaining said lock means relative to said bore while allowing limited projection of the lock means to a lock position beyond said other surface, an axially movable sleeve mounted on said driver for movement between a locked position and a released position, said sleeve having an inwardly turned front wall, an annular spring seat positioned inside said sleeve adjacent said front wall of said sleeve and including a lock key in said keyway operative to obstruct movement of said lock means into said groove when the sleeve is in said locked position whereby the lock means projects from said other of said opposed flat surfaces, said key being retracted from said locked position when said sleeve is moved to its said released position whereby said key no longer obstructs said lock means and the lock means can move into said bore, and - 17 a spring mounted inside said sleeve and bearing against said spring seat to bias said sleeve to said locked position.

4. A -driver according to claim 1 in which said spring is compressed between said spring seat and said driver.

A driver according to claim 2 including means limiting movement of said sleeve under influence of said compressed spring.

D 6. A driver according to claim 3 in which said motion limiting means comprises a limit stop engaged by said sleeve.

7. A driver according to claim 4 in which said limit stop comprises a coil of said spring engaged in a groove in said driver, and said sleeve is provided with means engageable with said coil.

8. A driver according to claim 4 in which said driver has an end opposite said driver end, said opposite end having a face from which spaced ears project, said sleeve sliding on the outside of said drive end and having tabs bent inwardly to engage said face when the sleeve has been moved to its lock position.

an axial groove means retaining movement relative to in which said lock 9. A socket wrench driver provided with t push-on/quick release locking arrangement comprising, a drive end on said driver having an even number of flat driver surfaces and having an axis, a cross bore through said drive end and intersecting opposed flat surfaces,-said cross bore having an axis, lock means mounted in said bore and having a length generally equal to the distance between said opposed surfaces, in one of said opposed flat surfaces, said lock means in said bore for said bore between a release position means is confined within said bore between said opposed flat surfaces and a lock position in which said lock means has limited projection beyond one of said opposed flat surfaces, an axially movable cylindrical sleeve mounted on said driver for movement between a first position and a released position, said sleeve having an inturned front wall and a rear shoulder, a washer seated on said shoulder, the rear of said sleeve being crimped onto said washer to hold it on said shoulder, 19 - control means mounted on said driver end and including a key lying in said groove and movable between a first position in which it overlies said lock means to urge said lock means to its said lock position and a release position in which it has moved away from the end of said driver to allow said lock means to move to its said release position in which it retracts into said cross bore, said control means also including an annular spring seat integral with said key and mounted inside said sleeve adjacent said front wall for movement with and with respect to said sleeve, a spring coiled around and mounted on said driver end inside said sleeve to act against said drive end and said spring seat to bias said spring seat against said front wall of said sleeve to urge said control means and said key towards said end, said sleeve being sized to confine said spring radially to prevent said spring from inverting, said control means and said key being movable with and with respect to said sleeve, said control means having enough clearance relative to said drive end and relative to said sleeve to allow rocking movement of the control means whereby said key can be raised by said lock means when said lock means is moved from its said lock position to its said release position.

10. A socket wrench driver having a cylindrical shaft provided with a push-on/quick release locking arrangement comprising, a drive end on said driver having an even number of flat drive surfaces and having an axis, a cross bore through the drive end intersecting opposed flat surfaces, said cross bore having an axis and an end at each of said opposed flat surfaces intersected by said bore, lock means mounted in said bore having a length generally equal to the distance between said opposed surfaces, a keyway in one of said opposed flat surfaces, means retaining said lock means relative to said bore while allowing limited projection of the lock means to a lock position beyond said other surface, an axially movable substantially cylindrical sleeve mounted on said driver for movement between a locked position and a released position, said sleeve having an inwardly turned front wall and an outwardly facing shoulder at its rear, a washer seated on said shoulder and having an internal diameter sliding on said cylindrical shaft, said sleeve being crimped over said washer to hold it against said shoulder, an annular spring seat positioned inside said sleeve adjacent said front wall of said sleeve for movement with and with respect to said sleeve and including a lock key in said keyway operative to obstruct movement of said lock means into said groove when the sleeve is in said locked position whereby the lock means projects from said other of said opposed flat surfaces, said key being free to retract from said locked position when said sleeve is moved to its said released position whereby said key no longer obstructs said lock means and the lock means can move into said bore when an external force acts on the projecting portion of said lock means, and a spring mounted inside said sleeve and bearing against said spring seat to bias said key and sleeve to their said locked positions, the clearance between said spring and said sleeve being small enough to prevent said spring from inverting during assembly or use.

11. A socket wrench driver substantially as described with reference to any one of Figures 1 to 5, Figures 6 to 8, or Figures 9 to 12 of the accompanying drawings.