CONNECTORS FOR TRANSMISSION OF ROTARY POWER

Abstract: Connector for the purpose of holding in coupling engagement a rotary output shaft of a motor and an extended (usually flexible) driven shaft for remote operation of tools, pumps and other equipment. The connector has a portion (23) having a cylindrical bore to receive both shafts in end to end coupling engagement as running fits therein. The connector has a base portion (24) adapted to mount it on the motor. A portion (25) which extends around portion (23) has apertures (30) therein receiving the legs of a locking handle (26) which pass through portion (25) and terminate in threaded sections on which nuts (27) hold springs (28) captive, thereby biasing the handle into locking position. In this position projecting portions (29a) on the legs of the handle (26) extend into the bore of portion (23) and are able to engage in an annular bight on the driven shaft thus holding the latter in the bore. The bight has a rectangular cross-section and this is matched by the cross-section of portions (29a). Handle (26) moves transversely of the bore.

Description: CONNECTORS FOR TRANSMISSION OF ROTARY POWER This invention relates to connectors and in particular to connectors adapted to bring together two members for the transmission of rotary power from one to the other. Such connectors are well known and have their main use in the field of transmitting rotary power from one location at which it is generated to a remote location at which it is to be used. For example, the power source may be a small liquid fuelled internal combustion engine and it is required that there be a power takeoff to a submersible pump, or a concrete vibrator, power saw or other tool, at a location at which it would be inconvenient to locate or handle) because of the weight or environment) the power source. Generally speaking, the power source has a drive shaft which, in rotating, supplied the power. It is generally provided (in conjunction with the shaft which is to be driven) with some clutching device such as a key and keyway, splined arrangement, or dog clutch. It is necessary that the shaft which is to be driven is held in engagement with the driving shaft and this is done by means of the type of connector, or, "power unit assembly", to which this invention relates. prior art dev ces wi l be ga ned by -reference to * ' '■ * " unexploded view of a power source (petrol engine-J.y .f its^.,-. ^ r „, (fc , mountings and . a prior art qonnector. The connector comprises, bell hou'sing 1, and trigger mechanism 2 ■*- - ■■ consisting of a spiral pin 3, spring 4 and rtafl'dal'ly ' • operable trigger 5. The power unit 11 is the petrol- motor which is mounted to base frame 22 via subframe 2, 21, spring 17, and bolts, nuts and washers (12, 13, 14, 15, 16, 18, 20) whereby the item 19 comprises an anti-vibration arrangement. Item 8 is a dog clutch which is slidingly fitted to shaft 10a of power unit 11 and fixed in position thereon longitudinally by tightening set screws 9. Key 10 engages keyways in shaft 10a and dog clutch 8, thus fixing the relative angular position of these two members. Bell housing 1 is mounted to unit 11 by means of a plurality of bolts/washers, 6/7, passing through holes 6a in its base into threaded holes 7a on unit 11. The shaft to be connected passes into the open end of bell housing 1 to mate with clutch 8. In order for this to happen, it is obviously constructed with or detachably fitted with a portion mating with the clutch 8. As previously stated, clutch 8 and the mating portion on the driven shaft are exemplary only of the type of connection. A splined drive arrangement or any other form of driving arrangement could be used. For convenience, the driven shaft is usually of the flexible type; the power unit could be an electric motor; however, these matters do not affect the present invention which resides in the connection itself. in operation, the connector above works as follows. Bell housing 1 has an opening la which receives trigger 5 and allows it to extend to the distal side and therethrough, where it is held by spiral pin 3, so that it cannot fall out. Opening la intersects the inside (cylindrical) surface of bell housing 1 to form slot 5d. Trigger 5 comprises a handle 5a, circular- cross-sectioned shank 5b, and a bight portion 5c. The surf ce of bight 5c is so shaped and positioned on trigger 5 that when the latter is in its assembled position, it can be rotated whereby bight 5c closes off slot 5d to complete the inside cylindrical surface . of bell housing 1. In this position of the trigger, the driven shaft can be fitted into the open end of the bell housing. The end of the driven shaft is of circular cross-section and when the driven shaft is in its clutched position with shaft 10a, an annular bight therein, (or rectangular cross-section) is aligned with the shank 5b of trigger 5. Normally spring 4 rotates shank 5b so that bight 5c is facing outwardly, and the part circular portion of the shank will then extend along slot 5d and protrude into the annular bight on the driven shaft, thus locking it into operational position, but leaving it free to rotate. By rotating trigger 5 against the spring 4, the driven shaft will be freed for removal from its operational position. In its locked position, the assembly rapidly wears away shank 5b of the trigger 5, owing to the lack of sufficient bearing area as would be provided, for example, by a rectangular shanked trigger fitting into the bight on the driven shaft. This is particularly so where any vibrator type tool is being driven as a proportion of the vibration is transmitted back up the shaft and hence to the restricted bearing area between the shaft and trigger shank. Clearly, the maximum bearing area would be obtained if the trigger shank had the same cross- sectional shape as that of the bight in the shaft to be driven. Obviously, this is not simply a matter of squaring off the shank of the trigger as it could not then be rotated into position in the bight, unless there was excessive clearance, which would of course aggravate the present problem. It is therefore the object of the present invention to provide a connector devide for positioning a driven shaft into coupling proximity with the drive shaft of a power unit which does not suffer from the above problems. Accordingly, the invention comprises a connector adapted to couple a rotary output shaft of a power source to a working shaft, wherein the ends of said shafts to be coupled include mutual engagement torque transmitting means, and the end of said working shaft to be coupled includes an annular groove therein, said connector comprising an open ended 0 tubular housing adapted to receive said shafts in end to end position whereby said torque transmitting means engage, means on said housing to fix said housing to said power source, a member movable between an operative and an inoperative position, 5 said member in said operative position engaging in said groove whereby in use to maintain said shafts in engagement, and in said inoperative position being free of said groove whereby, in use, said working shaft can be disengaged and removed 0 from said housing, means to move said member between said operative and inoperative positions and the position of said member which engages said groove having a cross-section complementary to that of the groove. 5 A better understanding of the invention will be gained by reference to Figures 2 to 6 of the accompanying drawings in which: Figures 2 and 3 are front elevations (respectively in unlocked and locked positions) of the connector 0 of the invention; Figure 4 is a side elevation thereof; Figure 5 is a plan view, and Figure 6 is an illustration of the side of the locking handle. In the drawings, the connector comprises a 5 cylindrical portion 23 mounted on a base 24, adapted to be fixed to a power unit with the output drive shaft protruding thereinto. The connector can be mounted to the power unit by any suitable means, for example, studs, or nuts and bolts. Portion 25 of the connector provides apertures 30 to hold the locking handle 26, which is to serve the same purpose as the trigger 5 of Figure 1. The legs of the locking handle 26 protrude from the portion 23 and terminate in threaded portions to which are affixed nuts 27. Springs 28, compressed between nuts 27 and the end walls of recesses 31, bias handle 26 into the locking position as shown in Figures 3 and 4. The shaft to be driven is a running fit in the cylindrical portion 23, and has an annular bight of rectangular cross-section at a position near its end corresponding to that the locking handle 26. The latter includes a portion 29 which limits the travel of the locking handle 26 laterally into the apertures 30 by engaging an external wall of the portion 23. The locking handle also includes members 29a which are adapted to engage in the bight of the driven shaft when it is locked in operational position. Members 29a are formed so that they have a rectangular cross-sectional portion complementary to the cross-section of the shaft bight protruding into the cylindrical bore of portion 23. (See Figure 3.) In this way a large bearing area is provided to accommodate any longitudinal forces transmitted along the driven shaft. in another embodiment, locking handle 26 has only one arm, and there is therefore only one member 29a. Nevertheless this provides a substantial improvement over the prior art device in view of the increased bearing area provided. In a further embodiment, members 29a are separate from handle 26, and each is pivotally mounted at one of its ends in portion 25 about an axis, parallel to that of the shaft. They are biased radially outwardly by spring means to be outside the base of portion 23. The legs of the handle 26 diverge towards the threaded ends so that as springs 28 pull handle inwardly, the gap between the legs diminishes and in bearing on members 29a, the legs force them radially inwardly to their locking positions against the action of their biasing spring means. yet another embodiment uses a rotary trigger action as in the prior art device. In this case the shank of the trigger 5 (see Figure 1) is cranked or formed with an eccentric cam-shaped cross-section; a member equivalent to member 29a is either pivotted as in the last mentioned embodiment, or mounted so as to be slidable at right angles to its length, and radially inwardly of the bore or portion 23, i.e. referring to Figure 3 for clarity, a member 29a would slide in the plane of the drawing bent at right angles to the direction of sliding in the embodiment of this Figure. Again the member 29a would be biased radially outwardly away from a locking position by spring means. On rotation of the trigger, its cranking or camming action would force member 29a into the locking position. It will be appreciated by those skilled in the art that the invention is not to be limited to the several embodiments described above, e.g. it is not necessary that the mechanism always biases itself to the locking position; locking could be accomplished by any simple mechanical means having positive action for locking and unlocking the mechanism. Similarly, the cross-section of the locking members need not necessarily be rectangular; as long as it complements the cross-section of the driven shaft bight an improved bearing area is provided compared to the prior art devices. Further, it should be appreciated that the invention comprehends within its scope protection not only for the connector per se but a power unit including the connector of the invention mounted thereon. v • ■ - " •

Claims: ? CLAIMS : 1. A connector adapted to couple a rotary output shaft otf a power source to a working shaft, wherein the ends of said shafts to be coupled include mutual engagement torque transmitting means, and the end of said working shaft to be coupled includes an annular groove therein, said connector comprising an open ended tubular housing adapted to receive said shafts in end to end position whereby said torque transmitting means engage, means on said housing to fix said housing to said power source, a member movable between an operative and an inoperative position, said member in said operative position engaging in said groove whereby in use to maintain said shafts in engagement, and in said in¬ operative position being free of said .groove whereby in use, said working shaft can be disen¬ gaged, and removed from said housing, means to move said member between said operative and inoperative positions and the position of said member which engages said groove having a cross-section complementary to that of the groove. 2. A connector as defined in Claim 1, wherein said respective cross-sections are rectangular in form. 3. A connector as defined in Claim 1, wherein said member is movable between said operative and inoperative positions by a manually operated lever or the like, and said member being biased inwardly of said housing whereby in use to maintain said working shaft in engaged position. 4. A connector as defined in Claim 3, wherein said member moves transversely of said housing through a tangentially aligned slot whereby to pass from said operative to said inoperative position. 5. A connector as defined in Claim 3 wherein - t RE 7 ^OMPI ■ y said member is pivotted to said housing about an axis parallel to said shafts, and said lever or the like operates a cammed surface engaging said member causing it, together with the biasing means, to be movable between said operative and inoperative positions. 6. A connector as defined in Claim 3, wherein said member constitutes a yoke which is slideable, in tangential- slots in opposite sides of said housing, between said operative and inoperative positions, whereby it is adapted to engage in the groove in said working shaft in use at opposite sides thereof. 7. A connector substantially as hereinbefore described with respect to Figures 2 to 5. 8. A power unit in which the output comprises a rotary shaft, said shaft having means on the end thereof adapted to engage in torque-transmitting relationships with cooperating means on the end of a working shaft to which power is to be transmitted, said unit in combination with a connector as defined in any one of the preceding claims, said connector fixed to said unit with said rotary shaft extending thereinto, whereby in use, said working shaft which includes an annular groove in the end thereof, can be coupled to said rotary shaft by insertion into the free end of said connector, and held therein by means of said member engaging in said groove.

Inventors: WILSON J
Applicants: HOOGANDYK K, WILSON J
Application year: 1981
Main classification: F16D1
IPC codes: F02B1, F16D1