GB2359723A

GB2359723A - Process for mounting flails,flail and clevis

Info

Publication number: GB2359723A
Application number: GB0102573A
Authority: GB
Inventors: Jacques Bachmann
Original assignee: Noremat SAS
Current assignee: Noremat SAS
Priority date: 2000-02-04
Filing date: 2001-02-01
Publication date: 2001-09-05
Anticipated expiration: 2021-02-01
Also published as: FR2804577B1; GB2359723B; GB0102573D0; FR2804577A1

Description

2359723 1 PROCESS FOR MOUNTING FLAILS, FLAIL AND CLEVIS The present

invention relates to a process for hooking or mounting flails for chopping or cutting apparatus such as cutters for chopping climbing stems, straw or maize stalks, and also to flails and clevises for implementing this process.

In known apparatus, flails comprise an eye which is threaded onto a clevis, such that when the flails are to be replaced, each clevis which bears a flail has to be dismantled. This takes a lot of time.

The process according to the invention consists of providing each flail with a hook, the central part of which has practically the same diameter as the working part of the clevis, and the opening of which is of a smaller dimension so that it cannot escape therefrom, and providing at least one, non-working, side of the clevis with a thinned part making it possible to insert the hook into 15 the clevis.

The invention also relates to a clevis and a flail which can be used to implement this process.

The present invention will now be described by way of non-limitative examples with reference to the attached drawings, in which:

Figures 1 and 2 show perspective views of the known prior arrangements; Figure 3 shows an example of embodiment of the hooked flail and the clevis; Figures 4a to 4c shows the hooked flail of Figure 3 being put in place; and, Figure 5 shows four examples of embodiment of the hooked flail which can be put in place in the clevis.

2 Referring to Figures 1 and 2, it will be seen that the known chopping or cutting apparatus comprises a shaft 1, which is driven in rotation at high speed, which by means of lugs 4 bears clevises such as 2 or 3 on which are threaded the eyes 7 of flails such as 5 or 6.

It will be understood that to change the flails such as 5 or 6 it is necessary to dismantle each clevis 2 or 3 by unscrewing the bolt/nut assembly 8.

When all the flails 5 or 6 borne by a shaft 1 have to be changed, this operation can take a very long time.

An example of the present invention is shown in Figure 3. It can be seen that the flail 10 does not include an eye, such as the eye 7 of Figures 1 and 2, threaded onto the clevis, but a hook 11.

This hook 11 comprises a central part 12, of generally circular section, the shape of which corresponds closely or exactly to that of the working part 16 of the clevis 14 and a narrowed section 13, the effect of which is that the flail 10 cannot come unhooked from the clevis 14.

In order to make it possible to hook the hook 11 onto the clevis 14, the latter comprises on at least one of its sides a thinned part 15 such that at this point the thickness of the clevis 14 is slightly less than the dimension of the opening of the hook at the narrowed section 13.

Figures 4a to 4c show how the hook 11 is hooked onto the clevis 14 by passing via the thinned part 15 thereof.

In Figure 5, it can be seen that several types of flails 10, four in the example illustrated, can be arranged on one and the same clevis 14.

The flail 10a is a flail of conventional shape corresponding to Figure 1.

3 The flails 1 Ob, 1 Oc and 1 Od correspond to the cutting flail of Figure 2: flail 1 Ob with a hook 11 turned towards the front, flail 10c with a hook 11 turned towards the back, and flail 10d being a double-reversible flail.

These three flails 1 Ob, 1 Oc and 1 Od have a specific shape: their hooks 11 are placed at one end of a shank 20 which bears at its other end a cutting piece 21 having a substantially rectangular shape; the cutting piece 21 of the flails 1 Ob and 1 Oc being slightly curved in the manner of a spoon, the cutting piece 21 of the flail 1 Od being double so as to be reversible.

The front part of the piece 21, which effects the cutting, may be bevelled 10 either in a single bevel or a double bevel.

Furthermore, in the case of the flails 10a and 10d, the position of the flail may be reversed depending on whether the hook 11 is turned towards the front or towards the back. It is then necessary to balance the flail such that its centre of gravity passes through the median plane of the hook 11.

In the case of the flail 10d, when the flail is inverted, the opposite side to the side which performs the cutting is subjected to a selfsharpening effect.

According to a variant embodiment, the thinned section 15 may be produced by forging by pushing back the material towards the inside of the clevis, which causes a bead to appear which reinforces the holding in place of the flail.

Of course, the present invention covers not only the process consisting of replacing the eye 7 with a hook 11, but also the products by means of which said process is implemented, that is to say a hooked flail 11 provided with a narrowed opening 13 and the clevis 14 provided with a thinned section 15 which makes it possible to make the hook 11 penetrate into the clevis 14.

4 During operation, the hook 12 rests on the working part 16 of the devis 14, whereas the thinned section 15 is formed on at least one of the nonworking sides of the clevis.

Claims

1. A process for mounting a flail on a clevis, consisting of providing the flail with a hook, the central part of which has substantially the same shape as the working part of the clevis and the opening part of which includes a narrowed section such that the flail cannot come unhooked from the working part of this clevis, and providing the clevis with a thinned part on one of its non-working parts making it possible to insert the hook of the flail into the clevis.

2. A clevis for implementing the process according to Claim 1 for a flail bearing a hook the clevis comprising on at least one of its sides, a thinned part.

3. A flail for implementing the process according to Claim 1, the flail including a hook adapted to be hooked to a clevis according to Claim 2.

4. A flail comprising a cutting piece, a shank extending from the cutting piece and a hook provided on the shank remote from the cutting piece, the entrance to the opening of the hook having a smaller dimension than the opening.

5. A flail according to Claim 3 or Claim 4, in which the hook comprises a central part having a shape which corresponds closely to that of the working part of a clevis to which it is to be mounted and a narrowed section, such that the opening of the hook is slightly greater than the thickness of the thinned part of the clevis.

6. A flail according to any one of Claims 3 to 5, the working part of which is of conventional shape.

6

7. A flail according to any one of Claims 3 to 6, in which the cutting part has a substantially rectangular shape and is connected to the hook by a shank.

8. A flail according to any one of Claims 3 to 7, in which the front part of the cutting piece is bevelled.

9. A flail according to any one of Claims 3 slightly curved.

to 8, the cutting part of which is

10. A flail according to any one of Claims 3 to 6, the cutting part of which is double such that the blade is reversible, its centre of gravity being located in 10 the median plane of the hook.

11. A flail according to any one of Claims 3 to 9, in which the hook is turned either towards the front or towards the back.

12. A process of mounting a flail on a clevis, substantially as described with respect to Figures 3 to 5 of the accompanying drawings.

13. A clevis substantially as shown in or as described with respect to Figures 3 to 5 of the accompanying drawings.

14. A flail substantially as shown in or as described with respect to Figures 3 to 5 of the accompanying drawings.