GB2044064A - Harvester stalk length sensor - Google Patents

Abstract

A stalk-length sensing apparatus in a harvester-thresher, has a plurality of sensors Sa, Sb, Sc disposed in juxtaposition on crop pick up 4, a mechanism to discriminate whether each of the said sensors has been shifted to sense the presence of a stalk from previous absence or has been shifted to sense stalk absence from previous presence, wherein when any particular one of the sensors has been shifted in the former manner, then the stalks that are shorter than the average center position of the said particular sensor and the sensor immediately adjacent thereto on the side of the stalk-head are sensed and when any particular one of the sensors has been shifted in the latter manner, then the stalks that are shorter than the average center position of the said particular sensor and the sensor immediately adjacent thereto on the side of the stalk-base are sensed. The cutting height of the harvester is adjusted in response to the sensed stalk length by rotation of the stalk transfer apparatus 8 about pivot fulcrum P. <IMAGE>

Description

SPECIFICATION Stalk-length sensing apparatus in a harvesterthresher This invention relates to a stalk-length sensing apparatus in a harvester-thresher, having a plurality of sensors desposed in juxtaposition at suitable intervals in the longitudinal direction of the object stalks for sensing whether there are stalks to reach them or not.

Conventional method of stalk-length sensing using such a plurality of sensors disposed in juxtaposition at suitable intervals in the longitudinal direction of the object stalks for sensing whether there are stalks to reach them or not, has been to sense up the stalks as such that are longer than the position of particular one of the sensors but shorter than the position of the sensor immediately adjacent thereto on the side of the stalk-head, when the said particular sensor has been shifted to sense stalk existence from previous non-existence. Such method thus quantizes the stalk length at the increments corresponding to the sensor intervals in the longitudinal direction of the stalks, sensing up all the stalks of the length within one such increment range as the stalks of one and the same quantized detection length.

High accuracy sensing with fine quantization of the stalk length has therefore required a lot of sensors to be closely juxtaposed, resulting in complicated structure and accordingly high cost. When abutment-type sensors to sense abutment of the stalks thereto are used as the said stalk sensors, there often is difficulty as a lot of such sensors are closely juxtaposed, besides the high cost mentioned above, also of lowering accuracy of the sensing because the stalk-head portions are deflected as a result of abutment thereon of many of the sensors, by the resilient restoring force thereof.

This invention is made in view of the actual status as above, and is characterized, in the stalk-length sensor apparatus as mentioned at the beginning, in that a mechanism is provided to discriminate whether each of the said sensors has been shifted to sense stalk existence from previous non-existence or has been shifted to sense stalk non-existence from previous existence and that the sensing apparatus is adapted to sense up, according to the results of the discrimination, the stalks as such that are longer than the position of particular one of the said sensors but shorter than the average center position of the said particular sensor and the sensor immediately adjacent thereto on the side of the stalk-head, when the said particular sensor has been shifted to sense stalk existence from previous non-existence, or as such that are shorter than the position of particular one of the sensors but longer than the average center position of the said particular sensor and the sensor immediately adjacent thereto on the side of the stalk-base, when the said particular sensor has been shifted to sense stalk non-existence from previous existence.

Making use of the fact that the stalks planted on the field show no abrupt fluctuations in the stalk length between adjacent lots, it has hereby been made possible to effect the stalk-length sensing in finer quantization for a given small number of juxtaposed sensors, with the discriminator mechanism functioning to divide each sensor juxtaposition interval into two quantizing increments in this novel stalk-length sensing technique.

The invention will now be described further, by way of example, with reference to the accompanying drawings, in which:- Figure lisa side elevation of front portion of a combine harvester used in this invention, Figure 2 is a side elevation showing mechanism for altering the position of rearward transfer apparatus, Figure 3 is a front view, in vertical section, showing the mechanism for altering the position of rearward transfer apparatus, Figure 4 is an electric circuit diagram and Figure 5 is a backside view of stalk-length sensing apparatus portion.

Figure 1 is a side elevation of front portion of a combine harvester which are supposed to have its body proper (3) equipped thereon with a crawler type running apparatus (1 ) and a threshing apparatus (2). In front thereof, there is attached a pickingup pretreatment assembly (9), for free raising and lowering in rocking movement about a rearward fulcrum (P), equipped with a pickup apparatus (4) to work on a plurality of rows of the stalks, a cutting apparatus (5), a transfer apparatus (6) for converging the cut stalks and a rearwardly stalk-transfer apparatus (8) for feeding the cut stalks to a threshing feeder chain (7), supporting both the stalk-head and stalk-base portions.

The said rearwardly stalk-transfer apparatus (8) is constructed for free raising and lowering in rocking movement about the pretreatment-assemblyfulcrum (P), thus to function as a threshing-depth adjustment apparatus to alter the portion of stalk supplied relative to the threshing feeder chain (7).

Figures 2 and 3 show mechanism for altering the position of the said rearwardly stalk-transfer apparatus (8), including an electric motor (10) whose output shaft (11) is operatively connected, via a worm-gearing reduction mechanism (12) and an endless chain (13), to a link mechanism (14) for altering the position.

The electric motor (10) is adapted to automatically be energized to rotate in one or the other direction or deenergized to stop the rotation, responsive to sensing results obtained by an apparatus (15), shown in Figure 1, for sensing stalk length of the picked-up stalks, the details of which are now described hereunder:: The said stalk-length sensing apparatus (15) is constructed with three sensors (15a), (15b), (15c) disposed in juxtaposition at suitable intervals in the longitudinal direction of the picked-up stalks, to rockingly be moved by abutment thereto of the stalks thus for sensing whether there are stalks to reach them or not, the rocking displacement of the sensors (1 Sa), 1 sub),(1 5c) being made to be detected by sensor switches (Sa),(Sb),(Sc), respectively, and to cooperate with a discriminator mechanism as described later for sensing up the stalk length as quantized in six stages.Describing more particularly, the discriminator mechanism is adapted to discriminate whether each of the said sensors (1 5a),(1 5b),(1 5c) has been shifted to sense stalk existence from previous non-existence or has been shifted to sense stalk non-existence from previous existence, for making it possible to sense up the stalks, with reference to Figure 5, as the shortest quantized stage stalks (L1 ) defined as shorter than the position of the bottom sensor (15c), when all the sensors (15a),(15b),(15c) sense non-existence of the stalks; as such (L2) that are longer than the position of the bottom senso r (15c) but shorter than the average center position of this sensor (1 sic) and the middle sensor (1 5b), when the status has been shifted from the above so that the bottom sensor senses stalk existence; as such (L4) that are longer than the position of the middle sensor (15b) but shorter than the average center position of this sensor (1 5b) and the top sensor (15a), when the status has been further shifted from the above so that the middle sensor senses stalk existence: and as the longest quantized stage stalks (L6) defined as longer than the position of the top sensor (1 Sal, when the status has been further shifted from the above so that this sensor (15a) senses stalk existence. On the other hand, it is further adapted to sense up the stalks as such (L5) that are shorter than the position of the top sensor (15a) but longer than the average center position of this sensor (15a) and the middle sensor (1 5b), when the status has been shifted from stalk-existence sensing by all the sensors (1 spa),(1 5b),(1 5c) so that the top sensor (1 5a) senses non-existence of the stalks; and as such (L3) that are shorter than the position of the middle sensor (15b) but longerthan the average center position of this sensor (1 5b) and the bottom sensor (1 5c), when the status has been further shifted from the above so that the middle sensor senses nonexistance of the stalks. It has thus been made possible to sense up the stalk length as quantized in six stages by dividing each of the intervals between the bottom sensor (15c) and the middle sensor (15b) and between the middle sensor (1 5b) and the top sensor (1 5a) into the repective two stalk-length quantization increments.

As seen in Figure 3, on stationary framing portion of the power drive system for altering the position of the said rearwardly stalk-transfer apparatus (8) there is attached a switch mechanism (16) for sensing, in rotary switching shift manner, the position of the said transfer apparatus (8). As shown in Figure 4, this switch mechanism (16) comprises stationary contacts (a),(b),(c),(a'),(b'),(c') of segment arc form electrically connected to the respective sensor switches (Sa),(Sb),(Sc) of the said stalk-length sensing apparatus (1 5), a pair of stationary contacts (d),(d') of segment arc form electrically connected to the respective relays (17),(18) provided for energizing the said electric motor (lOin one and the other directions, respectively, and a pair of movable contacts (e),(e') provided to be rotatable integrally with each other, with a support member (19) for the movable contacts (e),(e') constructed to be rotatable as operatively connected to output shaft (20) of the said worm-gearing reduction mechanism (12).

In Figure 4, designated at (Sd) is a starter switch for actuation of automatic threshing-depth adjustment, adapted to be in its ON stage only when a sensor (1 5d) shown in Figure 1, attached art a lower portion on backside of the pickup apparatus (4) is rearwardly pushed and rockingly moved. Designated at (SW1) is a "manual/automatic" mode selection switch, at (SW2) a manual operation switch to be used when manually adjusting the threshing depth, and at (SW3) a main switch.

Now, when the stalks become shorter as the combine proceeds then the threshing depth is adjusted accordingly deeper by means of the contact circuit through the stationary contact (d'), movable contact (e') and stationary contact (a'),(b'),(c') to energize the relay (17) for deeper threshing depth and to accordingly rotate the motor (10) in the one direction for such. The motor (10) in such rotation causes clockwise rotation of the support member (19) until the movable contact (e') comes off contact with the particular one of the said sensor switches (Sa),(Sb),(Sc), connected to the stationary contact (a'),(b') or (c') that is the lowermost one among the group sensing non-existence of the stalks, whereupon the relay (17) is deenergized and the motor (10) is accordingly stopped.The stop position in such threshing-depth deepening adjustment must therefore be represented by one of lines (F5),(F3),(F1) illustrated closely off the respective edges of the stationary contacts (a'),(b'),(c') on the clockwise rotation side, and these positions (F5),(F3),(F1 ) are properly set to correspond to the said respective quantized stalk-length stages (L5),(L3),(L1).

On the contrary, when the stalks become longer as the combine proceeds then the threshing depth is adjusted accordingly shallower by means of the contact ci rcuit through the stationary contact (d), movable contact (e) and stationary contact (a),(b),(c) to energize the relay (18) for shallower threshing depth and to accordingly rotate the motor (10) in the other direction for such. The motor (10) in such rotation causes counterclockwise rotation ofthe support member (19) until the movable contact (e) comes off contact with the particular one of the said sensor switches (Sa),(Sb),(Sc) that is the uppermost one among the group sensing existence of the stalks, whereupon the relay (18) is deenergized and the motor (10) is accordingly stopped.The stop position in such threshing-depth shallowing adjustment must therefore be represented by one of lines (F6),(F4),(F2) illustrated closely off the respective edges of the stationary contacts (a),(b),(c) on the counterclockwise rotation side, and these positions (F6,(F4),(F2) are properly set to correspond to the said respective quantized stalk-length stages (L6),(L4),(L2).

With the construction as above, threshing depth may stably be optimized by automatically rocking up and down the reawardly stalk-transfer apparatus (8) responsive to stalk-length fluctuation, while effecting the stalk-length sensing as quantized in six stages by discriminating whether each of the said sensors (1 5a),(1 5b),(1 5c) has been shifted to sense stalk existence from previous non-existence or has been shifted to sense stalk non-existence from previous existence, and effecting the threshingdepth adjustment accordingly in six stages, with proper position setting of the movable contacts (e),(e') and the said stationary contacts Designated in the drawing at (21 ) is a delay circuit as may be constructed in a well known manner for instance with capacitance and reistance, provided to delay the starting or stopping actuation of the automatic threshing-depth adjustment for a suitably set period of time (as may for instance be 0.6 second or so) when the said starter switch (Sd) is turned ON or OFF. The start-delaying function will serve for preventing unintended threshing-depth adjustment as might otherwise occur during a period of time after a stalk or a cluster of stalks have actuated the starter switch (Sd) until such properly reach the corresponding sensor (15a),(15b) or (1 5c). On the other hand, the titop-delaying function will serve for preventing unintended stopping of the threshingdepth adjustment as might otherwise occur when there have been no subsequent stalks supplied upon completion of the cutting or reaping operation or upon localized vacancy of the stalks.

Furthermore, designated at (22a),(22b) are the delay circuits for delaying the actuation of the said respective relays (17,(18) to thereby prevent threshing-depth adjustment actuation even if there be abrupt fluctuation in the sensed stalk length and thus to stabilize the adjustment operation. In order to prevent the danger of overloading the threshing apparatus (2), the delay time for the threshing-depth shailowing line is made shortherthan the delay time forthethreshing-depth deepening line.

Though the discriminator mechanism is constructed in the embodiment using the properly disposed movable contacts (e),(e') and the rotation ary contacts (a)(b)(c),(a')(b')(c'), it is obvious that the discriminating function may as well be performed with the machanism constructed in any other suitable manner.

This invention may as well be performed in such a manner that the result of the stalk-length sensing is displayed by a display mechanism using for instance a lamp or the like.

Claims (5)

1. A stalk-length sensing apparatus in a harvester-thresher, having a plurality of sensors disposed in juxtaposition at suitable intervals in the longitudinal direction of the object stalks for sensing whether there are stalks to reach them or not, the stalk-length sensing apparatus in a harvesterthresher being characterized in that a mechanism is provided to discriminate whether each of the said sensors has been shifted to sense stalk existence from previous non-existence or has been shifted to sense stalk non-existence from previous existence and that the sensing apparatus is adapted to sense up, according to the results of the discrimination, the stalks as such that are longer than the position of particular one of the said sensors but shorter than the average center position of the said particular sensor and the sensor immediately adjacent thereto on the side of the stalk-head, when the said particular sensor has been shifted to sense stalk existence from previous non-existence, or as such that are shorter than the position of particular one of the sensors but longer than the average center position of the said particular sensor and the sensor immediately adjacent thereto on the side of the stalk-base, when the said particular sensor has been shifted to sense stalk non-existence from previous existence.

2. The stalk-length sensing apparatus in a harvester-thresher as recited in claim 1, characterized in that the havester-thresher is a combine equipped with a threshing apparatus having a threshing feeder chain, that an automatic threshingdepth adjustment apparatus is provided as is capable of altering the position of stalk supply relative to the threshing feeder chain and that the said result of the stalk-length sensing is used as input signal for controling the automatic threshing-depth adjustment apparatus.

3. The stalk-length sensing apparatus in a harvester-thresher as recited in claim 1, characterized in that the harvester-thresher is a combine equipped with a threshing apparatus having a threshing feeder chain, that a manually-operated threshing-depth adjustment apparatus is provided as is cabable of altering the position of stalk supply relative to the threshing feeder chain and that the said result of the stalk-length sensing is used as input signal for stalk-length display mechanism so that an operator may manually operate the threshing-depth adjustment apparatus responsive to the stalk-length display.

4. The stalk-length sensing apparatus in a harvester-thresher as recited in any of claims 1-3 for this invention, wherein the said sensors are adapted to be displaced by abutment thereon of the stalks.

5. A stalk-length sensing apparatus in a harvester-thresher, constructed and arranged to operate substantially as herein described with reference to and as illustrated in the accompanying drawings.