WO2008037006A1

WO2008037006A1 - Machinery hitches

Info

Publication number: WO2008037006A1
Application number: PCT/AU2007/001421
Authority: WO
Inventors: John Hubert Tapp
Original assignee: Tapp, Margaret, Joan
Priority date: 2006-09-26
Filing date: 2007-09-26
Publication date: 2008-04-03

Abstract

The invention is a power take-off device for use between a tractor and an implement to be used by the tractor, which device includes a shaft having telescopic coaxial members adapted to extend between the tractor and a connector device adapted to engage with a complementary part on the implement by connection means.

Description

MACHiNERY HITCHES

Technical Area

This invention relates to machinery hitches and in particular to quick-hitch arrangements such as those used in association with the rear of a tractor for attaching the machinery to be drawn by the tractor.

Background to the Invention

It is well-known in the agricultural industries, in particular, to need to change the implements which are connected to tractors and there have been developed means whereby these can be connected without the tractor driver having to leave the driver's seat.

These means normally include an A-frame or the like connected to the tractor's three-point linkage and which has means to engage with a connector member permanently attached to the implement, so the driver can reverse up to the implement, adjust the height of the three-point linkage, and reverse the tractor into position, locking the linkage to the tractor. These arrangements are, in operation, generally satisfactory.

There has not however been a facility available to automatically connect a tractor's power take-off to the implement thus requiring that some person has to physically move the power take-off into position relative to the required position on the implement and physically make the connection.

This has several disadvantages. Firstly, it makes it essential for the linkages to be arranged so that a person can physically get to the power take-off to make the connection and this often means that the construction of the implement and its attachment is not optimum; secondly, it can be difficult and somewhat dangerous to make this connection, and thirdly, as mentioned above, the tractor driver has to move from his tractor to effect the connection, or there has to be a second person assisting him.

Outline of the Invention

It is an object of the invention is to provide, in association with an automatic implement-connecting linkage, a means whereby the power take-off can be connected automatically at the same time.

It is preferred that the shaft have two telescopic coaxial members and extension means to normally maintain the shaft in an extended position when not connected to an implement. It is further preferred that this extension means be a spring.

It is also preferred that the connector device have means whereby it is retained in position relative to the shaft to enable it to be moved into contact and engagement with a complementary part on an implement said implement having an implement drive.

It is preferred that the connection means is the coupling of complementary splined components associated with the connector and the implement.

It may however be preferred that the connection means be a dog clutch arrangement associated with the connector and adapted to engage with a receptor on the implement.

It is further preferred that an A frame locating device on the tractor be received during connection by an A frame receiver associated with the implement.

It is preferred that there are universal joints at each end of the shaft, the forward universal joint being part of the three point linkage arrangements and there being means whereby the shaft can be held in a required position so that it can generally be in alignment with the implement drive.

It is also preferred that the engagement between a plate on the rearward portion of the shaft and the device on the implement be by means of a dog-clutch or the like whereby rotation of the shaft is directly transmitted to the implement. -A-

In order that the invention may be more readily understood, one particular embodiment of the invention will be disclosed by way of non limiting example with reference to the accompanying drawings.

Brief Description of the Drawing Figures

Fig.1 Shows the quick Coupling Tractor Power Take Off (PTO) in extended mode; Fig. 2 Shows the quick Coupling Tractor PTO in compressed (working) mode;

Fig. 3 Shows the shaft of the invention coupling to an implement;

Fig. 4 Shows a three point linkage A-frame PTO support mechanism;

Fig. 5 Is a side view of the invention approaching an implement;

Fig. 6 Shows a side view of an alternate dog-clutch type coupling;

Description of an Embodiment of the Invention

In the embodiment of the invention 10 described here the power take-off arrangement can be considered to consist of a shaft having two end assemblies 11, 12 in the form of universal joint yokes, one of which 11 is adapted to be connected to the tractor power take-off and the other 12 to the implement.

Connected between these end assemblies is cylindrical tube shaft 14 consisting of outer tube 15 in telescopic relationship with inner tube 16 these being held in relation to each other by retaining cord 19 with shaft 14 being held in relation to the A-frame of the tractor by support cord 20, as shown in Figure 4, consisting of chains or the like, the precise means used being non limiting in the invention. The outer and inner tubes of shaft 14 are locked as far as rotational movement is concerned. This may be by the formation of splines in the members or some form of keying arrangement with the precise means not being restricted in the invention.

Located within shaft 14 there is a helical spring about which inner tube 16 can move when the spring is compressed, the arrangement being such that under normal circumstances, the inner tube 16 adopts a position extending outwardly from the outer tube 15 as shown in Figure 1.

While in this preferred embodiment of the invention this spring is located through the length of shaft 14 it is envisaged that it could be located solely within either of its component tubes.

In this embodiment of the invention the outer end of tube 16 is connected to a universal joint 25 supported by yoke 12. Also connected to the universal joint there is a connector member 30 (shown in Figure 2) which extends rearwardly and has on or associated with its outer surface 35 a female splined receiver 40 for coupling to an implement.

Alternatively it is envisaged that this coupling may be effected by means of a plate 50 having dog-clutch members 53 thereon to engage with members 54 associated with implement receptor 51 as shown in Figure 6.

Also associated with member 30 is means 33 for providing universal joint alignment by means of spring compression used to retain this member substantially coaxial with the axis of the telescopic shaft components It will be appreciated that without some form of support, the member 30 would be able to rotate about the universal joint and tend to be downwardly-directed because of its weight at the end of the joint.

At the end of the member 30 there is a further universal joint part, the other part of which is connected directly to the power take-off of the tractor.

The arrangement is such that, if the connection device 10 is connected to the power take-off of the tractor, it is held substantially horizontal by the chain or the like connecting it to the A-frame 18, the inner tube component 16 is outwardly- directed relative to the outer tube component 15, because of the action of the spring there-against, and the axis of connector 30 is basically horizontal as its axis is restrained by the spring acting against the rear of this.

The coupling means between the connector 30 and an implement is shown in Figure 3 wherein female splined receiver 40 has associated with it a non splined alignment guide 45 to aid in the connection of splined instrument shaft 46.

In use, and as described, the device is to be used is association with a releaseable implement and the A-frame can be provided with connector-pins which are adapted to inter-engage with snap-lock members on the implement.

Figure 5 shows the situation where tractor 60 with A frame 62 is reversed towards the implement 70 associated with an implement A frame receiver 65 such that splined implement shaft 46 can engage with female splined receiver 40. In the alternative coupling means described, the power take-off arrangement extends outwardly beyond the inter-engaging members and the driver can manipulate the position of the power take-off member and guide the plate 15 having dog clutch members 53 into a cylindrical sleeve 57, or the like, which sleeve has, at its inner end, the drive for the device which is in the form of a plate 51 which has co-operating dog-clutch means 54 adapted to engage with the dog- clutches in the rearwardly-directed plate 50.

Once this inter-engagement is effected, the driver can, if necessary, alter the height of the A-frame somewhat so that the connectors on the A-frame and the implement are in a position for inter-relationship with those on the implement, at which time the tractor is moved further rearwardly so that the engagement is effected.

Whilst this movement is occurring, the inner shaft tube 16 moves relative to the outer shaft tube 15 so that the power take-off arrangement is maintained until engagement is completed and, at this time, the power take-off is in a condition for operation as the splined members engage or dog-clutches on the two adjacent plates engage, and the implement can readily be used.

When it is desired to change the implement, it is only necessary to release the coupling between the implement and the A-frame, drive the tractor forward, the two telescoping members of the shaft 14 will extend until they reach their maximum extension, at which time splined connectors will disconnect or, in the dog clutch embodiment, the plate will simply move away from the cylindrical sleeve on the implement, and the attachment will be available to automatically connect to the next implement which is to be attached to the tractor. Whilst there has been described herein a specific embodiment of the invention, it is to be understood that this description is by no means limiting.

The crux of the invention lies in the provision of a rearwardly-extending member which has portions which can be moved longitudinally from the position where they extend outwardly, to a position in which the power -take-off means is connected to the implement.

It has means to ensure that this assembly is normally outwardly-directed from a tractor so that it is in a position to enable association with the implement and means whereby the rearward end thereof, which is outwardly of a universal joint, is normally held in a position where it can extend into a receptacle on the implement, but this means does not prevent movement around the universal joint when the power take-off is being used.

Any arrangement which provides these features is within the scope of the invention.

Claims

The claims defining the invention are as follows:

1. A power take-off device for use between a tractor and an implement to be used by the tractor, which device includes a shaft having telescopic coaxial members adapted to extend between the tractor and a connector device adapted to engage with a complementary part on the implement by connection means.

2. A power take-off device as claimed in claim 1 having two telescopic coaxial members and extension means to normally maintain the shaft in an extended position when not connected to an implement.

3. A power take-off device as claimed in claim 2 wherein the extension means is a spring.

4. A power take-off device as claimed in claim 3 wherein the connector device has means whereby it is retained in position relative to the shaft to enable it to be moved into contact and engagement with a complementary part on an implement said implement having an implement drive..

5. A power take-off device as claimed in claim 4 wherein the connection means is the coupling of complementary splined components associated with the connector and the implement.

6. A power take-off device as claimed in claim 4 wherein the connection means is a dog clutch arrangement associated with the connector and adapted to engage with a receptor on the implement.

7. A power take-off device as claimed in claim 5 or claim 6 wherein an A frame locating device on the tractor is received during connection by an A frame receiver associated with the implement.

8. A power take-off device as claimed in claim 7 wherein universal joints are provided at each end of the shaft, with the forward or tractor end universal joint being part of a three point linkage arrangement and there being means whereby the shaft can be held in a required position so that it can generally be in alignment with the implement drive.

9. A power take-off device as claimed in claim 8 wherein engagement between the connector device and the implement is such that rotation of the shaft is directly transmitted to the implement.

10. A power take-off device as claimed in claim 9 wherein spring means are provided for providing universal joint alignment to retain it substantially coaxial with the axis of the shaft components.

11. A power take-off device as claimed in any one of claims 1 to claim 10 wherein a person driving a tractor can simply reverse the tractor to align the tractor A frame with the implement A frame receiver to effect electrical connection of the tractor and implement once the connection means has been engaged.