GB2058007A

GB2058007A - Tractor load-handling attachments

Info

Publication number: GB2058007A
Application number: GB7936738A
Authority: GB
Original assignee: Massey Ferguson Perkins Ltd
Current assignee: Perkins Engines Group Ltd
Priority date: 1979-10-23
Filing date: 1979-10-23
Publication date: 1981-04-08
Also published as: IT8025541A0; DE3039753A1; FR2467529A1; IT1209362B; GB2058007B; FR2467529B1

Abstract

Material handling apparatus comprising a U-shaped support frame (14) to fit round the front end of the tractor and attachment means to attach the frame to the tractor comprising attachment means (32, 60) at the leading end of the frame (14) and on the tractor that cooperate as the tractor is driven into the frame (14) and restrains the frame (14) vertically on the tractor, and attachment means at each side of the frame (14) comprising a saddle member (70) secured to the support frame (14) and a seat member (82) fastenable to the tractor so as to engage beneath the saddle member (70) as the tractor is driven into the frame to attach the apparatus, guide structure (96) that is adapted to guide the seat member (82) laterally and vertically relative to the saddle member (70) as the tractor is driven into the support frame (14), a laterally directed aperture in the saddle member (70) and a similar aperture (94) in the seat member (82) that come into axial alignment when the seat member (82) is fully engaged beneath the saddle member (70), and a pin (not shown) that can be inserted in the aligned apertures to secure the saddle member (70) on the seat member (82). <IMAGE>

Description

SPECIFICATION Material handling apparatus This invention rela.tes to material handling apparatus and in particular though not exclusively, to such apparatus in the form of a loader for attachment at the front of an agricultural tractor. Such apparatus is usually provided with a variety of interchangeable material handling implements such as a manure fork, a bucket and a silage grab.

An important feature of an agricultural loader is that it should be a quick and easy operation to mount it on and detach it from a tractor. The loader then need be carried by a tractor only when the loader is in use.

Our British Patent No. 1513139 discloses a detachable agricultural loader comprising a U-shaped support frame that is adapted to fit round the front end of a tractor and carries a pivoted boom that is adapted to carry a material handling implement. The frame is provided with legs that engage the ground to support the loader when it is detached from a tractor, and that can be removed from engagement with the ground when the loader is in use on a tractor.Attachment means is provided at each side of the support frame to attach the frame to a tractor, each attachment means comprising a single rearwardly projecting pin secured to a leading portion of the frame and engagable with a socket in a first plate secured to the tractor and a pair of rearwardly projecting pins that are laterally spaced apart and are secured to the frame behind said single pin and are engagable with a pair of sockets in a second plate secured to the tractor. Guide means are provided on each of said plates to guide the pins into the socket as the tractor is driven into the support frame to attach the loader.

It has been found that this known loader can be easily and quickly attached to and detached from a tractor if the geometry remains true, but that this may become difficult if the support frame is distorted due to careless treatment by the tractor driver. An object of the present invention is therefore to provide this loader with improved attachment means that is less sensitive to distortion of the support frame.

This object is achieved according to the invention by providing material handling apparatus comprising a U-shaped frame to fit round the front end of the tractor and attachment means at each side of the frame to attach the frame to the tractor each comprising a saddle member secured to the support frame and a seat member fastenable to the tractor so as to engage beneath the saddle member as the tractor is driven into the support frame to attach the loader, guide structure that is adapted to guide the seat member laterally and vertically relative to the saddle member as the tractor is driven into the support frame, a laterally directed aperture in the saddle member and seat member that come into axial alignment when the seat member is fully engaged beneath the seat member, and a pin that can be inserted in the aligned apertures to secure the saddle member on the seat member.

The use of co-operating saddle and seat members that are locked together by a lateral pin allows greater tolerances in the fit between these two members as compared with the tolerance required between the pins and sockets of the known double-pin type attachment means, in which a close fit is essential if the loader is to be rigidly attached to the tractor. The saddle and seat members therefore engage and disengage more easily and are less prone to bind together as a result of distortion of the support frame.

The pin according to the invention must be received as a close fit in the apertures to hold the saddle and seat members rigidly together, but the fact that the pin is separate allows it to be adapted for easy insertion and removal.

Preferably, the pin is an eccentric pin having an end portion of reduced diameter and with an outer cam surface that is eccentric relative to the. pin axis. This end portion can be inserted into the two apertures if they are not fully aligned and rotated within the apertures to further align them. Preferably, the pin can be provided with-successive cam surfaces of progressively increasing diameter along it's length so that the pin can be inserted and rotated in stages to bring the apertures into complete alignment. A long handle attached across the head of the pin facilitates rotation and insertion or withdrawal.

The saddle preferably comprises an upper portion and an outer downwardly projecting portion with the aperture formed in it. The seat member engages beneath said upper portion on the inside of the outer portion, and preferably carries a forwardly directed guide structure having an inclined outer edge that co-operates with the lower and/or inner faces of the saddle member to produce a lead-in or centring action. The line or point contact between the guide structure and saddle reduces frictional forces and improves the centring action. Most simply, the guide structure comprises a rod or bar, preferably with a degree of resilience, that projects forwards from the seat and is preferably inclined both downwards and inwards.

The invention will now be described by way of example with reference to the accompanying drawings in which: Figure 1 is a perspective view from the rear, above and to one side of a loader for attachment to an agricultural tractor.

Figure 2 is a perspective view of part of the loader Fig. 1 and a tractor provided with attachment means for engagement with the loader.

Figure 3 is a perspective view of a rear corner of the loader of Figs. 1 and 2 shown attached to the tractor via the attachment means.

Figure 4 is a perspective view of a front corner of the loader of Figs. 1 and 3 shown attached to the tractor via the attachment means.

Figure 5 is a side elevation of the attachment means at the rear corner of the loader before being engaged as in Fig. 3.

Figure 6 is a plan view of the attachment means of Fig. 5, and Figure 7 is a rear view of the attachment means connected to the rear corner of the loader in Fig. 1.

As shown in the drawings, material handling apparatus in the form of a loader 10 for attachment to a tractor 1 2 comprises a Ushaped support structure 14, a boom 16, a material handling implement in the form of a bucket 18, and thrust means comprising a pair of hydraulic rams 20 which operate in unison.

Support structure 14 comprises a rigid Ushaped frame 22 having side arms 23 to fit round the front of tractor 12, and a pair of upright pivot posts 24, fixed to the ends of the arms of the frame.

The frame 22 has a pair of parking legs 26 that are supported one on each side of the frame in an upper U-shaped bracket 28 that is pivotally connected to the frame and a lower clamp block 30 that is mounted on a forwardly projecting pin 32 carried at the lower end of an arm 34 projecting downwards from the frame. The clamp block 30 is retained on the pin 32 by a lynch pin 36, and a clamp bolt 38 can be rotated in the clamp block to clamp the leg at a set height.

When not in use, the leg can be raised by releasing the clamp bolt 38, and removing the lynch pin 36 so that the clamp block 30 can be pulled forwards off the pin 32 and the leg swung upwards about the pivot of bracket 28 and pushed rearwards through the slots in the bracket so as to lie along the length of the frame side arm 23. The lynch pin 36 is then used to hold the leg in this stowed position by engagement in the lug 40 on the side arm 23, as shown in Fig. 3.

Boom 1 6 comprises a pair of rigid beams 42 connected by a strut 44 to form an Hshaped structure. Bucket 1 8 is pivotally mounted on hooks 46 formed at the end of beams 42 in the usual manner. A latch (not shown), releasable from the tractor cab, is provided to retain the bucket in the position shown in Fig. 1.

The other end of each beam 42 is pivotally connected by a pin 48 to its respective pivot post 24.

Hydraulic rams 20 are each connected at the piston end by respective pivot pins 50 to pivot posts 24, and at the cylinder end by respective pivot pins 52 to the beams 42. The rams are connected in parallel by hoses 54 having a hydraulic inlet connector 56 which allows rapid connection to the tractors hydraulic system, and which prevents escape of hydraulic fluid upon disconnection therefrom.

In order that the loader may be attached to the tractor, attachment means are provided at each side towards the front and rear of the frame 22. The front attachment means comprises the pin 32 at the lower end of the arm 34, this pin being extended rearwards and provided with a tapered end for engagement in a socket 58 in a plate 60 carried at one end of a transverse bracket 62 bolted beneath the front of the tractor 1 2.

A guide structure 64 is provided to guide the pin 32 into each socket 58, the structure 64 comprising a sloping base flange 68 providing lateral guidance, and an inwardly flared side flange 69 providing lateral guidance.

The rear attachment means comprises a saddle member 70 in the form of an L-shaped bracket that is connected to the lower ends of the pivot posts 24 so that an upper portion 72 projects outwards and an outer portion 74 projects downwards.

A pair of strengthening webs 76 are connected between the top of the saddle member 70 and the outer post 24, the rearmost web being aligned with the rear edge of the saddle 70 and acting as an abutment plate, as described hereinafter. A boss 78 is provided on the outer face of the portion 74 and an aperture 79 is formed through it.

A seat member 82 is carried at one end of a U-shaped transverse bracket 84 that is bolted beneath the tractor towards the rear of the engine. The seat members 82 comprises two laterally spaced upright plates 86, 88 that project forwards from a support plate 90 and carry an annuler boss 92 therebetween with an aperture 94 passing through both plates and the boss, this aperture being of the same diameter as the aperture 78 in the saddle member 70. A guide structure 96 is provided to guide the seat member 82 beneath the saddle member 70, the guide struc- ture comprising a rod connected along the top edge of the outer upright plate 86 so as to project forwards and be inclined downwards and inwards. In this way, it is ensured that the free forward end of the guide rod 96 engages beneath the saddle so that the saddle slides over the guide in point or line contact with it as the tractor is driven into the frame 22.

The seat member 82 is also provided with an upright guide peg 98 at the top of the front edge of the inner upright plate 88 so as to co-operate with a guide plate 99 that is connected to the underside of the saddle member 70. The guide plate 99 is inclined towards the outer portion 74 of the saddle member over a first forwardly projecting part of its length and then extends parallel to the outer portion 74, the spacing of these parallel portions being sufficient to receive the guide structure and seat member therebetween.

When the seat member 82 is fully engaged beneath the saddle member 70, the support plate 90 abuts the rearmost web 76. The apertures 78, 94 are then in alignment and an eccentric pin 100 can be inserted through them to lock the saddle member in position on the seat member. The pin 100 has a reduced diameter end portion 102 with an outer annuler surface that is eccentric relative to the axis of the pin, so that this end portion can be inserted into the apertures when they are only partially aligned and rotated to bring them more fully into alignment. A further eccentric portion 103 of slightly greater diameter is provided on the pin to allow a second similar aligning operation before the pin can be fully inserted.

A handle 104 fastened across the head of the pin allows it to be manipulated in the apertures and is also used to hold the pin in the apertures and for storing the pin. For these purposes a loop of wire 106 is fastened to the outer pivot post 24 between the webs 76 and a ring of wire 108 is provided on this loop 106. The ring 108 can be dropped over one end of the handle 104 to hold the pin in place in the apertures. Also, when the pin is removed from the apertures one end of the handle can be inserted through the loop 106 and the pin 100 located between the two webs 76.

In order to detach the loader from the tractor, the operator lowers bucket 1 8 so that it rests on the ground, dismounts from the tractor, removes the lynch pins 36 from the lugs 40 to free the legs 26, pulls the legs forwards and swings them down into contact with the ground, engages the clamp blocks 30 on the forward ends of the pins 32 and inserts the lynch 36 in the holes in the pins 32 to retain the blocks in place, tightens the clamp bolts 38, disconnects the hydraulic connectors 56, and also disconnects the trip (not showri) from the bracket latch, and removes the eccentric pins 100 and stows them between the webs 76. The operator then backs the tractor away from the loader. The loader is then left supported by its legs 26 ready to be reattached to the tractor.

To mount the loader on the tractor the above sequence of operations is carried out in reverse. The legs 26 support the loader in the position in which it was left so that when the tractor is driven forwards towards the loader, the rear attachment means comprising the seat members 82 and saddle members 70, and the front attachment means comprising the pins 32 and sockets 58 are approximately axially aligned. As the tractor moves forwards, the rod-shaped guides 96 engage beneath the saddle members 70 and engage the outer portions 74 to align the saddle members with the seat members 82 and engage the upper portions 72 so that the saddle members 70 ride up onto the seat members. When the abutment plates 76, 90 engage the eccentric pins 100 are then inserted in the apertures 78, 94 and locked in place with the rings 108.The hydraulic system and bucket latch are then connected and the legs finally raised.

It will be appreciated that the rod-shaped guides 96 are simple members that can cause a substantial centring movement of the saddle members relative to the seat members, this action being enhanced by the natural resilience of the guides. Further, the point or line contact of the guides with the saddle members ensures minimum frictional resistance to the engagement and disengagement of the saddle and seat members. There is no need for a close tolerance in the engagement between the saddle and seat members so the likelihood of these members binding togehter to resist engagement or separation is much reduced. Further, any difficulty in fully engaging the saddle and seat members can be overcome by the use of the eccentric pins, provided the reduced end portion of each can be located in the partially aligned apertures.

The long handles allow a substantial torque to be applied in order to insert and remove the pins.

In an alternative embodiment of the invention, the guide rods 96 are replaced by Lsection plate members having an upper portion that is inclined downwards towards the front and an outer upright portion that is inclined towards the front. The seat member may comprise rearwards extensions of these upper and outer portions, the aperture for the eccentric pins being formed in the outer portions.

In another alternative embodiment, the saddle members are inverted channel-section members and the seat members are also inverted channel-section members that fit within the saddle members, the channel-section seat members having inwardly tapered sides and a downwardly tapered upper web portion so as to form a tapered nose to guide the seat beneath the saddle. The apertures for the eccentric pins are formed through the side portion of both channel-section members.

Claims

1. Material handling apparatus comprising a U-shaped support frame to fit round the front end of the tractor and attachment means to attach the frame to the tractor comprising attachment means at the leading end of the frame and on the tractor that cooperate as the tractor is driven into the frame and restrains the frame vertically on the tractor, and attachment means at each side of the frame comprising a saddle member secured to the sup port frame and a seat member fastenable to the tractor so as to engage beneath the saddle member as the tractor is driven into the frame to attach the apparatus, guide structure that is adapted to guide the seat member laterally and vertically relative to the saddle member as the tractor is driven into the support frame, a laterally directed aperture in the saddle member and seat member that come into axial alignment when the seat member is fully engaged beneath the saddle member, and a pin that can be inserted in the aligned apertures to secure the saddle member on the seat member.

2. Apparatus as claimed in claim 1 in which the pin has an end portion of reduced diameter and an outer cam surface that is eccentric relative to the pin axis.

3. Apparatus as claimed in claim 2 in which the pin is provided with successive cam surfaces of progressively increasing diameter away from its reduced end portion.

4. Apparatus as claimed in any one of the preceding claims in which the saddle member has an upper portion and an outer downwardly projecting portion with said aperture formed in it.

5. Apparatus as claimed in claim 4 in which the seat member engages beneath said upper portion on the inside of the outer portion and carries a forwardly directed guide structure having an inclined outer edge that cooperates with the lower and/or inner faces of the saddle member to produce a lead-in or centering action.

6. Apparatus as claimed in claim 5 in which said guide structure comprises a rod or bar that projects forwards from the seat.

7. Apparatus as claimed in claim 6 in which the rod or bar is inclined inwards.

8. Apparatus as claimed in claims 6 or 7 in which the rod or bar is inclined downwards.

9. Apparatus as claimed in any one of claims 6 to 8 in which the rod or bar is resilient.

1 0. Apparatus as claimed in any one of the preceding claims in which the attachment means at the leading end of the frame comprises a rearwardly projecting pin at each side of the frame that is engagable with a socket in a plate fastenable to the tractor.

11. Apparatus as claimed in claim 10 which includes a leg at each side of the frame that can be brought into engagement with the ground to support the apparatus when not mounted on a tractor.

1 2. Apparatus as claimed in claim 11 in which each leg is pivotally mounted on the frame so as to swing down into engagement with the ground, and carries a socket member that is engagable with a forward extension of said rearwardly projecting pin and can be retained thereon by a fastener.

1 3. Apparatus as claimed in claim 1 2 in which each leg is pivotally connected to the frame by a pivoted bracket through which the leg can slide so as to be movable to a stowed position lying longitudinally of the side portion of the frame.

1 4. Apparatus as claimed in any one of the preceding claims in which a boom is pivotally connected to the frame and is adapted to carry a material handling implement.

1 5. Material handling apparatus substantially as herein described with reference to the accompanying drawings.