NZ212701A

NZ212701A - Pick-up hay harvester with quickly detachable cutters in conveyor duct

Info

Publication number: NZ212701A
Application number: NZ212701A
Authority: NZ
Inventors: Josef Steffens
Original assignee: Strautmann & Soehne
Priority date: 1984-07-10
Filing date: 1985-07-10
Publication date: 1988-04-29
Also published as: EP0167903A1; DE3562438D1; EP0167903B1; DE3425287A1; ATE33914T1; DE3425287C2

Abstract

1. A cutter mechanism for stalk crop materials comprising a plurality of blades (6) which are arranged releasably in a conveyor passage (7) of a harvester and which are mounted pivotably about a respective pivot axis (9) fixed to the wall of the conveyor passage (7) and which are held in the operative position by a respective pin (12), the pin being connected to the upper end of a spring (13) and being supported in a depression (17) provided on the rear side of each blade (6) which is in opposite relationship to the pivot axis (9), wherein the lower end of the spring (13), adjacent to the pivot axis (9), is connected to a further pin (23), the blades (6) being pivotable at least partially out of the conveyor passage (7) against the force of the spring (13) upon co-operating with stones or the like foreign bodies, characterised in that the pin (12) which is connected to the upper end of the spring (13) is mounted slidably in a slot (20) in the support structure of the harvester and that the pin (23) which is connected to the lower end of the spring (13) lies positively in a recess (26) in the blade (6) and separably from the blade (6).

Description

Priority Cat::'- ): , \P.'.7lr&ty.

Complete Specification Filed: ICkrfr^ C; 3So* m i Publication Date: ... .?£ ARB .1388 P.O. Journal, No: ....iH>C?7t -0 o\ Patents Form no: 5 PATENTS ACT 1953 COMPLETE SPECIFICATION "CUTTING TOOL" WE, B. STRAUTMANN & SOHNE GmbH & Co a company organised and existing under the laws of West Germany of D-4518 Bad Laer, West Germany, hereby declare the invention for which we pray that a patent may be granted to us, and the method by which it is to be performed, to be particularly described in and by the following statement:- 21270i The present invention concerns a cutting tool for fodder, consisting of several knives that are detachably mounted in a conveyor duct of a harvesting appliance. Each knife can be swivelled about a horizontal axis and is maintained in the operating position by means of a spring loaded locking device and can swing out, at least partially, from the conveyor duct if contacted by stones or similar foreign bodies.

A cutting tool of this kind is well known. In one known cutting tool, a tension spring with one end fixed to a harvesting appliance operates on a locking device connected to its other end and provided with a track supporting roller so that the track supporting roller in the operating position of the knife lies in a recess at the rear of the knife. The locking device, in the action of the knife with a foreign body, due to the rotation of the knife moves in opposition to the spring tension and the track supporting roller during this movement rolls off on the rear of the knife. After the passage of the foreign body the knife is swung back through the locking device in co-operation with the tension spring to its original operating position.

Reliable security against foreign bodies is given by this well-known construction, but because of the stationary setting of one end of the tension springs, the complete removal of the knives for the purpose of repair or maintenance work, (for example the regrindingof the cutting edges of the knives) is possible only with difficulty. As the tension spring during the disengagement of the knife is at no stage in a slack state, the locking device must be kept against the spring tension during the wh^>Ie process. The same problem is met also in the replacement of the knife after the sharpening is finished.

In practice, because of the difficulties involved, complete removal of the knives from the harvesting appliance is dispensed with, and maintenance work is carried out on the spot on those areas of the knives which are tolerably accessible. This is under the given conditions naturally difficult and expensive in time and cost.

An object of the present invention therefore is the development of a cutting tool, in which the taking out or insertion of each knife is possible in the simplest manner, quickly and therefore inexpensively.

The present invention provides a cutting tool for fodder, said tool including a plurality of knives mounted in a conveyor duct of a harvesting appliance, each knife being mounted such that said knife can be swivelled about a horizontal axis and is maintained in the operating position by means of a spring-loaded locking device; each knife having a first cutting edge and being arranged to be swung at least partially out of the conveyor duct, against said spring loading, if a force exceeding a predetermined force is exerted on the knife by a foreign body present in the duct; one end of each tension spring of each said locking device being connected to a first bolt which is arranged to engage a recess in the knife said first bolt being held in an open-ended slot formed in a cam plate secured to said conveyor duct, the other end of each said spring being connected to a second bolt which is arranged to slide in a slot provided on a bolt handle on the body of the harvesting appliance and in an index notch on a second edge of said knife; each said spring and said corresponding first and second bolts being detachable from the corresponding knife; and said first and second bolts being releasably braced against the knife by said spring.

By means of this construction it is possible, by releasing Mi.— ■>* 3- I 2 SFEB1988 r 212701 the bolt fixed in the recess of the knife and the spring attached to it, to remove the knife from a locked i.e. operational position so that the lower end of the spring in that part of the knife remote from the swivel axis is secured under tension to the knife.

In a preferred embodiment of the invention, the bolt attached to the lower end of the spring is fixed to a bolt handle, and by turning this bolt handle about a rotating bolt connected to the bolt handle and likewise resting in the recess of the knife the corresponding end of the spring can very easily be drawn out of the recess of the knife and thereby the knife released from its locked position. 111A 1 n y\ J n M J M rtT T -P1 TT 1 T K 1 "T -p ^ /i oV* A ^ P 1 "1 TT swivel axis of the harvesting appliance with a hook-shaped catch. When the knife is being mounted in the harvesting appliance, the hook-shaped catch is first of all hung on the fixed pin and finally arrested by means of the bolt handle.

The above-described knife mounting means not only easier mounting of the knife but also guarantees that the knife cannot of itself fall down in the course of dismantling the equipment.

By attaching one end of the spring to a bolt which is arranged so that it can slide in a slot in the harvesting appliance, each knife also is arranged to swing harmlessly out of contact with any foreign body in the duct whose impact on the knife exceeds a predetermined force.

Thus, the present invention provides a cutting tool which is resistent to damage by foreign bodies and in which a knife release mechanism enables single knives to be removed and inserted without A ft . 21270 the use of special tools.

By way of example only, a preferred embodiment of the present invention is described in detail, with reference to the accompanying drawings, in which:- Fig. 1 is a cross section through a harvesting appliance with a cutting tool incorporating the invention.

Fig. 2 is a cross section as in Fig. 1 with different positions of the knife of the cutting tool.

Fig. 3 is a back view of a conveyor duct of the harvesting appliance seen in the direction of the arrow III-III in Fig. 1.

Fig. 4 is a knife in accordance with the invention.

Figs. 1 and 2 show (in a schematic representation) part of a harvesting machine which basically consists of a pick-up attachment 1, a conveyor duct 7 connected to the pick-up attachment , several knives 6 protruding into the conveyor duct, and a rotating cylinder 3 forming part of a reciprocating plate feeder 4 from which conveyor tines 5 extend into the conveyor duct 7.

Cut fodder lying on the ground is taken up by the spring tines 2 of the pick-up attachment 1 and conveyed to the beginning of the conveyor duct 7. Subsequently the fodder is seized by the conveyor tines 5 of the rotating cylinder 3 and pushed through the conveyor duct 7 and against the knives 6 which are arranged athwart the direction of movement of the fodder, so that the fodder is cut according to the intervals between the knives 6. As the conveyor tines 5 move between the knives 6 the cut fodder is conveyed to the end of the conveyor duct 7 and arrives over a conveyor belt 27, which is arranged on the back wall of the conveyor duct 7. The conveyor belt 27 leads to the hopper - 5 212701 of a car loader (not shown).

If a foreign body (e.g. a stone) is introduced into the conveyor duct 7 with the fodder, and said stone runs up against the edge of one of the knives 6, the knife swings out of the conveyor against the pressure of a biasing spring, so that the foreign body can freely pass through the conveyor duct 7 and the blade edge of the knife 6 is not damaged.

Each knife 6 is arranged as follows:- a bolt 12 is supported in a recess 17 of the knife 6 and is connected to one end of a spring 13. The recess 17 is provided with an operating threshold 11 which is so formed that it provides a resistance to the swinging of the knife 6 out from the conveyor duct 7. This resistance is overcome by the force exerted on the knife by the foreign body.

The bolt 12 braced in the recess 17 of the knife 6 is held in an open-ended slot 20 formed in a cam plate 21 the plane of which is parallel to the plane of the corresponding knife on the back wall of the conveyor duct 7.

The bolt 12 can slide freely up and down the slot 20 as the knife 6 pivots into or out of the duct 7.

The lower end of the spring 13 is connected to a bolt 23 which is supported in a recess 26 of the knife 6; the recess 26, (as is shown also in Fig. 4) is located in that portion of the knife remote from a swivel axis 9. Likewise a rotatable bolt 24 is supported in the recess 26. by the shape of the recess; bolts 24 and 23 are fixed to a bolt handle 22.

When the bolt handle 22 is reversed, by pivoting about the bolt 24, the spring 13 is first of all strectched and then is :-''p A. relaxed when the bolt handle 22 has been completely reversed/' in which position the bolt handle 22 can be released from the recess 26, the knife 6 is in a non-operational position and can freely be removed.

To prevent the knife 6 falling down after the release of the bolt handle and in order to make possible the easy removal of the knife, the knife 6 is connected to a fixed pin (hot shown) at the swivel axis 9 by hook-shaped catch 15.

In the inserting of the knife 6 this firstly is suspended with the catch 15 on the swivel axis 9 and the rotating bolt 24 of the bolt handle 22 is laid in the recess 26 and the bolt handle 22 is swung round so that the knife 6 is retained in * o ' the operational position by the bolts 12, 23 connected withpy the spring 13. 20NOV 1987 pin and fixed outside the normal range of positions of the knife 6 limits the position of the knife 6 within the conveyor duct 7 in the direction of the rotating cylinder 3.

As described above the present invention makes it possible to move each blade between operational and non-operational positions simply be manual release of the bolt handle 22 and without using any additional equipment.

On the side of the knife fixed to the upper end of the spring 13 an index notch 14 is provided. When the bolt 12 is inserted in the notch 14 by manual movement of the knife 6, the knife 6 is held in a non-cutting position (see the position of the lowest knife in Fig. 2). Also a length of cut can be freely chosen, fixed only by the number of knives 6 standing in the cutting position.

As is shown in Fig. 4, the knife is formed somewhat in the shape of a triangle so that the cutting edge 28 has a concave shape and the back of the knife next to the cutting edge 28, in 1270 the area in which the recess 17 and the index notch 14 are provided, has a convex shape.

The convex shape of the back of the knife prevents a build-up of the cut fodder between the back wall 10 of the conveyor duct 7 and the back of the knife 6, which would otherwise lead to breakdowns.

In Fig. 3 the position of the single knives 6 vis-a-vis one another is shown. From this it can be seen that the knives 6 (only one of which is shown in full in Fig. 3) are arranged in reverse order to one another in a well-known fashion. This arrangement of the knives 6 prevents the knives all coming into use at the same time in cutting fodder, which would lead to an excessive impact stress upon the knives 6. © 8 - c' J"-* 21

Claims

WHAT WE CLAIM IS:-

1. A cutting tool for fodder, said tool including a plurality of knives mounted in a conveyor duct of a harvesting appliance, each knife having a first cutting edge and being mounted such that said knife can be swivelled about a horizontal axis and is maintained in the operating position by means of a spring-loaded locking device; each knife being arranged to be swung at least partially out of the conveyor duct, against said spring loading, if a force exceeding a predetermined force is exerted on the knife by a foreign body present in the duct; one end of each tension spring of each said locking device being connected to a first bolt which is arranged to engage a recess in the knife said first bolt being held in an open-ended slot formed in a cam plate secured to said conveyor duct, the other end of each said spring being connected to a second bolt which is arranged to slide in a slot provided on a bolt handle on the body of the harvesting appliance and in an index notch on a second edge of said knife; each said spring and said corresponding first and second bolts being detachable from the corresponding knife; and said first and second bolts being releasably braced against the knife by said spring.

2. The cutting tool as claimed in Claim 1, wherein said one end of each spring is engagable with the corresponding knife adjacent the said horizontal axis.

3. The cutting tool as claimed in Claim 1 or Claim 2 wherein each said first bolt is secured to the bolt handle 210?o: which is rotatable about a rotatable bolt which also is secured to said handle and is engagable with said recess in the knife.

4. The cutting tool as claimed in any preceding claim wherein each knife is detachably connected about the corresponding horizontal axis by a hook-shaped catch.

5. The cutting tool as claimed in any preceding claim, wherein each slot formed in said cam plate is open only at one end, said plate extending parallel to the plane of the corresponding knife on the rear face of the conveyor duct.

6. The cutting tool as claimed in any preceding claim wherein each knife is substantially three-sided in plan and the cutting edge is concave and the rear edge of the knife is convex.

7. A cutting tool substantially as hereinbefore described with reference to and as shown in the accompanying drawings. B. STRAUTMANN & SOHNE GmbH & CO. by their authorized agents P.L. BERRY & ASSOCIATES per: 10