Connection structure in agricultural tractor vehicle

Abstract

To provide a connection structure which can reduce a turning radius during turning of an agricultural tractor vehicle such that a traction device does not interfere with a work machine.SOLUTION: A connection structure 10 includes a work machine 30 at a rear part of an agricultural tractor vehicle 60, and a traction device 70 at a rear side of the work machine 30, the structure connecting the traction device 70 to a tractor vehicle connection part 21 provided at a rear side pf the agricultural tractor vehicle 60. A connection structure is formed between the tractor vehicle connection part 21 and a connection part 41 of the traction device 70, the structure connecting each of a plurality of connection members 11, ..., 11 via a joint part 12 which allows a swing in a right-left direction, in which the joint part 12 is composed of one piece or a plurality of pieces. Further, a swing range of the plurality of connection members 11, ..., 11 generated by a travel of the agricultural tractor vehicle 60 is configured to be restricted such that the traction device 60 does not interfere with the work machine 30.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a coupling structure for coupling a towed device to a towing coupling section at the rear of an agricultural towing vehicle, and more particularly to a coupling structure for coupling a work implement at the rear of an agricultural towing vehicle, and a towing device connected to the rear of the work implement. [Background technology]

[0002] Agricultural towing vehicles such as tractors are used to harvest crops, cultivate land, spread fertilizer, and so on, with various working machines attached. Examples of the working machines include machines that automatically harvest various agricultural crops such as cabbage, burdock, potatoes, and green soybeans. When harvesting agricultural crops with such working machines, a basket for storing the agricultural crops is required, so a towed device equipped with a basket is connected to a coupling at the rear of the agricultural towing vehicle. The towed device is equipped with wheels such as tires so as to follow the agricultural towing vehicle.

[0003] As another example, when a work machine such as a liquid fertilizer spreader is attached, a towed device equipped with a liquid fertilizer storage tank (tank) is connected to the rear of the agricultural towing vehicle in order to supply liquid fertilizer to the liquid fertilizer spreader.

[0004] When the agricultural towing vehicle moves in a straight line, the towed device follows the agricultural towing vehicle, so there is no problem, but when the agricultural towing vehicle turns, a problem occurs in which the towed device interferes with the working machine. In order to solve this problem, a connecting structure has been proposed in the past, for example as shown in Patent Document 1, for preventing interference with the lower links provided on the left and right sides when connecting the towed device to a connecting part provided in the center of the rear of the agricultural towing vehicle.

[0005] In Patent Document 1, for example, when a work machine such as a fertilizer spreader is connected to the rear of an agricultural towing vehicle to spread fertilizer in a field, the fertilizer spreader is raised by a lower link to perform the work. The towed device is located behind the fertilizer spreader and connected to a connecting part at the rear of the agricultural towing vehicle. This connecting structure includes a vertical arm that is attached to the connecting part so as to be rotatable about a vertical axis and extends upward from the connecting part, and a main arm that is provided above the vertical arm and extends rearward from the vertical arm, and the towed device is connected using the main arm. As a result, since the vertical arm stands upright from the connecting portion, the main arm of the towed device will not interfere with the lower link even when the towed device turns. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] JP 2022-98224 A Summary of the Invention [Problem to be solved by the invention]

[0007] The connecting structure of Patent Document 1 is applied to a work machine such as a fertilizer spreader that has a lower link for lifting the fertilizer spreader, but since the towed device is connected via a connecting structure that does not interfere with the lower link, the distance between the agricultural towing vehicle and the towed device is approximately the same as before. Therefore, when the agricultural towing vehicle turns, the turning radius of the towed device remains the same as before. However, the application range of the connecting structure is limited.

[0008] On the other hand, in the case of a work machine such as a fertilizer spreader that does not have the above-mentioned lower link, if the towed device is not positioned further rearward than before, a problem occurs in that the towed device interferes with the fertilizer spreader when the agricultural towing vehicle turns. However, if the distance between the agricultural towing vehicle and the towed device is increased, for example by using an auxiliary coupling, a problem occurs in that the turning radius of the towed device becomes larger.

[0009] The present invention has been made in consideration of the above circumstances, and has an object to provide a connecting structure that, when a work machine is provided at the rear of an agricultural towing vehicle and a towed device located behind the work machine is connected, can reduce the turning radius so that the towed device does not interfere with the work machine when the agricultural towing vehicle turns. [Means for solving the problem]

[0010] The invention described in claim 1 is a coupling structure for an agricultural towing vehicle configured to have a work machine at the rear of the agricultural towing vehicle, and a towed device disposed behind the work machine and coupled to a towing vehicle coupling section provided at the rear of the agricultural towing vehicle, so that the towed device is towed by the agricultural towing vehicle together with the work machine. The coupling section of the agricultural towing vehicle and the coupling section of the towed device are formed by a coupling structure in which a plurality of connecting members are connected by joints that allow them to swing relative to each other in the left-right direction, and the joint section is composed of one or more joints, and the swing range of the plurality of connecting members generated by the traveling of the agricultural towing vehicle is restricted so that the towed device does not interfere with the work machine.

[0011] The invention as recited in claim 2 is characterized in that in the above-mentioned first aspect, the plurality of connecting members are formed with stoppers that regulate the range of swing between the front and rear connecting members.

[0012] The invention as set forth in claim 3, in the above-mentioned claim 1 or 2, is characterized in that the bending angle of the towed device with respect to the forward movement direction of the agricultural towing vehicle is 40 to 45°.

[0013] The invention described in claim 4 is characterized in that in any one of claims 1 to 3 above, the multiple connecting members form a swing lock device that stops / releases swinging between the front and rear connecting members.

[0014] The invention described in claim 5 is characterized in that, in any one of claims 1 to 4 above, a connecting member among the multiple connecting members that connects to the towing vehicle connecting portion restricts left-right swinging relative to the forward direction of the agricultural towing vehicle to a small extent.

[0015] The invention described in claim 6 is characterized in that, in the above-mentioned first claim, the work machine is a liquid fertilizer spraying device, and the towed device is equipped with a tank for storing liquid fertilizer to be supplied to the liquid fertilizer spraying device. Effect of the Invention

[0016] According to claim 1 of the present invention, since a working machine is provided at the rear of the agricultural towing vehicle, the connecting structure connecting the towed device arranged at the rear of the working machine to the towing vehicle connecting part of the agricultural towing vehicle becomes long. If this is left as it is, the turning radius of the towed device will be large when the agricultural towing vehicle turns. However, in the connecting structure of the present invention, the multiple connecting members swing left and right at the joints, so the turning radius of the towed device is small. Moreover, since the swing range of the multiple connecting members is restricted, the turning radius is such that the towed device does not interfere with the working machine.

[0017] According to claim 2 of the present invention, even if multiple connecting members are used, by forming a stopper that limits the swing range between the front and rear connecting members, the bending angle between the front and rear connecting members can be changed little by little, so that the towed device can turn smoothly.

[0018] According to claim 3 of the present invention, even if the bending angles between the front and rear connecting members of the multiple connecting members are different, it is desirable that the bending angle of the towed equipment relative to the forward direction of the agricultural towing vehicle is ultimately 40 to 45°, in order that the towed equipment can turn smoothly without interfering with the working machine.

[0019] According to claim 4 of the present invention, by using the swing lock device to stop the swinging of the front and rear connecting members in the connecting structure relative to each other, it becomes easy to connect the towed equipment to the towing vehicle connection part of the agricultural towing vehicle.

[0020] According to claim 5 of the present invention, since the connecting member that connects to the towing vehicle coupling section is connected to the area of ​​the work equipment, if the towing vehicle coupling section swings so as to bend significantly, the towed equipment may interfere with the work equipment. By restricting the swing to a small amount, it is possible to prevent the towed equipment from interfering with the work equipment.

[0021] According to claim 6 of the present invention, the turning radius of the towed device can be reduced without the towed device interfering with the liquid fertilizer spraying device, improving work efficiency. That is, the liquid fertilizer spraying device as a working machine has a width because it is necessary to efficiently spray liquid fertilizer on a field. Moreover, since the towed device is provided with a tank for storing liquid fertilizer, it is unavoidably made longer in overall length, and it becomes significantly larger in size. Therefore, if the turning radius becomes larger, the work efficiency decreases because it takes time and effort to handle it when spraying fertilizer on a field. According to the present invention, it is possible to solve such problems. [Brief description of the drawings]

[0022] [Figure 1] Fig. 1(a) is a schematic plan view showing a state in which a tractor and a liquid fertilizer tank truck are connected using a connection structure for an agricultural towing vehicle according to the present invention, and Fig. 1(b) is a side view of Fig. 1(a). [Diagram 2] FIG. 2 is a plan view showing the bending angle of the liquid fertilizer tank truck relative to the forward direction of the tractor in FIG. [Diagram 3] FIG. 2 is a perspective view of a coupling structure in the agricultural tractor according to the present invention. [Figure 4] 4 is a schematic diagram showing the plan view of FIG. 3 and the bending angle of the second connecting member relative to the first connecting member. FIG. [Diagram 5] 11 is a plan view showing a stopper that restricts the swinging of a second connecting member relative to a first connecting member. FIG. [Figure 6] Fig. 6(a) is a plan view showing a swing locking device that stops the swing of a second connecting member relative to a first connecting member, and Fig. 6(b) is a side view showing the swing locking device as seen from the side of Fig. 6(a). [Figure 7]FIG. 2 is a perspective view of a cut injector and a liquid fertilizer tank truck coupled to a tractor. [Figure 8] FIG. 8 is a plan view of FIG. [Figure 9] FIG. 9 is a plan view showing the connection structure of the present embodiment in FIG. 8. [Figure 10] 8. FIG. 8 is a front view of the cut injector as viewed from the line VIIIa-VIIIa in FIG. [Figure 11] 8. FIG. 8 is a partial side view of the cut injector as viewed from the line VIIIb-VIIIb in FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0023] Hereinafter, a coupling structure for an agricultural tractor according to an embodiment of the present invention will be described with reference to the drawings. As shown in Figures 1(a) and (b), the coupling structure 10 in the agricultural towing vehicle of this embodiment has a working implement 30 at the rear of the agricultural towing vehicle 20, and a towed device 40 is disposed behind the working implement 30, and the towed device 40 is coupled to a towing vehicle coupling portion 21 provided at the rear of the agricultural towing vehicle 20. In this embodiment, a tractor is used as the agricultural towing vehicle 20, the working machine 30 is a liquid fertilizer spraying device that uses a cut injector, and the towed device 40 is a liquid fertilizer tank car equipped with a tank for storing liquid fertilizer to be supplied to the cut injector.

[0024] The coupling structure 10 for an agricultural towing vehicle, which is the main component of this embodiment, couples between the towing vehicle coupling section 21 of the tractor 20 and the coupling section 41 of the liquid fertilizer tank vehicle 40, and is basically a coupling structure 10 in which a plurality of coupling members 11, ..., 11 are coupled with joint sections 12 that enable them to swing left and right relative to one another. Moreover, the coupling structure 10 is configured with one or more joint sections 12. That is, if there are two coupling members 11, there is one joint section 12, if there are three coupling members 11, there are two joint sections 12, and if there are n coupling members 11, there are (n-1) joint sections 12. In addition, the swing range of the multiple connecting members 11, 11 caused by the travel of the tractor 20 is restricted so that the liquid fertilizer tank car 40 does not interfere with the cut injector 30. For example, the multiple connecting members 11, 11 can form a stopper 13 that restricts the swing range between the front and rear connecting members 11, 11.

[0025] In this embodiment, as shown in FIGS. 1(a) and 1(b), a connecting structure 10 that is particularly composed of a first connecting member 11a, a second connecting member 11b, and one joint portion 12 will be described. As shown in Figures 3 and 4, the joint portion 12 is configured so that the first connecting member 11a and the second connecting member 11b are supported by a vertical shaft 12b extending vertically of the bearing portion 12a so that they can swing left and right relative to each other.

[0026] For example, as shown in Figures 3 and 4, the joint portion 12 has upper flange portion 15a and lower flange portion 15b protruding above and below the front portion of the second connecting member 11b, and upper flange portion 14a and lower flange portion 14b protruding above and below the rear portion of the first connecting member 11a are fitted between the upper flange portion 15a and the lower flange portion 15b. Furthermore, a bearing portion 12a is provided between the upper flange portion 14a and the lower flange portion 14b, and the upper flange portion 14a and the upper flange portion 15a, as well as the lower flange portion 14b and the lower flange portion 15b, are each journaled by a vertical shaft 12b of the bearing portion 12a. The front end of the first connecting member 11 a is connected to a towing vehicle coupling portion 21 of the tractor 20 , and the rear end of the second connecting member 11 b is connected to a coupling portion 41 of the liquid fertilizer tank vehicle 40 .

[0027] Furthermore, the swing range of the first connecting member 11a and the second connecting member 11b caused by the travel of the tractor 20 is restricted so that the liquid fertilizer tank car 40 does not interfere with the cut injector 30. For example, the first connecting member 11a and the second connecting member 11b can form a stopper 13 that restricts the swing range.

[0028] As an example of the stopper 13, as shown in Figure 3, the first connecting member 11a and the second connecting member 11b have the upper flange portion 14a and the lower flange portion 14b of the first connecting member 11a inserted between the upper flange portion 15a and the lower flange portion 15b of the second connecting member 11b, so that both side plates 16, 16 between the upper flange portion 15a and the lower flange portion 15b of the second connecting member 11b form stopper 13 that abuts against the upper flange portion 14a and the lower flange portion 14b of the first connecting member 11a. Therefore, as shown in FIG. 4, the position where the side plates 16, 16 abut against each other determines the bending angle α of the second connecting member 11b relative to the first connecting member 11a, and the bending angle α can be adjusted by adjusting the positions of the side plates 16, 16.

[0029] As another embodiment of the stopper 13, as shown in FIG. 5, stoppers 13a, 13a can be formed on both sides of the rear part of the first connecting member 11a, and stoppers 13b, 13b that abut against the stoppers 13a, 13a can be formed on both sides of the front part of the second connecting member 11b.

[0030] In addition, it is desirable that the first connecting member 11a restricts the left-right swinging of the towing vehicle coupling part 21 of the tractor 20 to a small value relative to the forward direction of the tractor 20. The reason for this is that, since the first connecting member 11a is connected to the area of ​​the cut injector 30 as shown in Figures 1(a) and 1(b), if the left-right swinging becomes large so that the towing vehicle coupling part 21 is bent significantly, for example, the liquid fertilizer tank car 40 may interfere with the cut injector 30. By restricting the swinging of the first connecting member 11a to a small value, it is possible to avoid interference of the liquid fertilizer tank car 40 with the cut injector 30.

[0031] In this embodiment, as shown in Figures 1(a) and 1(b), guides 17, 17 are provided against which the left and right side surfaces of the first connecting member 11a abut. These guides 17, 17 can be attached to, for example, a main frame 31 of a cut injector 30, as shown in Figures 9 and 10.

[0032] In addition, it is preferable that the multiple connecting members 11, 11 are formed with a swing lock device 18 that stops and releases the swinging of the front and rear connecting members 11, 11. For example, as shown in Figures 6(a) and 6(b), swing lock devices 18, 18 are formed on both side surfaces of the rear part of the first connecting member 11a and the front part of the second connecting member 11b.

[0033] More specifically, the swing locking devices 18, 18 have second bases 18d, 18d protruding from both sides of the front of the second connecting member 11b, locking arms 18a, 18a are rotatably provided on the second bases 18d, 18d, and locking holes 18b, 18b are formed at the tips of the locking arms 18a, 18a. Meanwhile, first bases 18c, 18c protruding from both sides of the rear of the first connecting member 11a, and screw holes 18f, 18f are formed in the first bases 18c, 18c, into which locking bolts 18e, 18e are inserted and screwed into the locking holes 18b, 18b of the locking arms 18a, 18a.

[0034] Therefore, by inserting the locking bolts 18e, 18e into the locking holes 18b, 18b of the locking arms 18a, 18a on both the left and right sides and screwing them into the screw holes 18f, 18f of the first base portions 18c, 18c, the swinging of the second connecting member 11b relative to the first connecting member 11a is stopped and locked.

[0035] Furthermore, in order to hold the unlocked locking arms 18a, 18a, third base portions 18g, 18g are protruded from both side surfaces of the second connecting member 11b, and screw holes 18h, 18h are formed into which locking bolts 18e, 18e are inserted and screwed into the locking holes 18b, 18b of the locking arms 18a, 18a that have been rotated rearward.

[0036] As described above, by using the swing lock devices 18, 18 to stop the swinging of the front and rear connecting members 11, 11 in the connecting structure 10 relative to each other, it becomes easy to connect the liquid fertilizer tank truck 40 to the towing vehicle coupling part 21 of the tractor 20. If the swinging is not locked, the connecting members 11, 11 will swing relative to each other and be in an unstable state, making it difficult to connect the liquid fertilizer tank truck 40 to the towing vehicle coupling part 21 of the tractor 20.

[0037] After the liquid fertilizer tank truck 40 is connected to the towing vehicle connection part 21 of the tractor 20 via the connection structure 10 of this embodiment, the locking bolts 18e, 18e of the swing locking devices 18, 18 are removed from the screw holes 18f, 18f of the first base parts 18c, 18c to release the lock. Next, the locking arms 18a, 18a rotate rearward, and the locking bolts 18e, 18e are inserted into the locking holes 18b, 18b and screwed into the screw holes 18h, 18h of the third base parts 18g, 18g to be held.

[0038] Next, the cut injector 30 used in this embodiment will be described. The cut injector 30 is a spraying device that sprays liquid fertilizer such as livestock manure into the soil of a farm field. As an example, the cut injector 30 is towed by the rear of a tractor 20, for example, as shown in Figures 7 to 11, and includes a main frame 31 that is connected to the tractor 20 via a connecting portion 31a.

[0039] In addition, a distribution device 32 that distributes liquid fertilizer is arranged on the upper part of the main frame 31, and multiple discharge injectors 35, ..., 35 are supported by injector support members 34, 34 at the lower part of the main frame 31 so that they are arranged laterally to the left and right with respect to the direction of travel of the tractor 20.

[0040] The injector support members 34, 34 are provided so as to be rotatable in the left-right direction so as to be pushed down or pulled up by actuators 34a, 34a such as cylinders connected to the main frame 31.

[0041] The liquid fertilizer LF distributed by the distributor 32 is supplied to each discharge injector 35,...,35 provided at the tip of a plurality of supply hoses 33,...,33 as shown in Fig. 8 to Fig. 11. In this embodiment, ten supply hoses 33,...,33 and ten discharge injectors 35,...,35 are provided. In addition, in Fig. 8 to Fig. 11, the supply hoses 33, . . . , 33 are not shown, and the flow of the liquid fertilizer LF is mainly indicated by dotted lines.

[0042] Furthermore, the cut injector 30 is provided with furrow making rollers 36,...,36 for forming furrows in the field in front of the travel direction of each discharge injector 35,...,35, and is provided with cutters 37,...,37 between each furrow making roller 36,...,36 and each discharge injector 35,...,35 for scraping out soil at the bottom of the furrows formed by the furrow making rollers 36,...,36. Also, behind each discharge injector 35,...,35, rollers 38,...,38 for covering the top of the furrows with soil after spraying the liquid fertilizer LF are provided.

[0043] As described above, the injector-related mechanism 39 consisting of the discharge injector 35, groove forming roller 36, cutter 37, and roller 38 shown in FIG. 11 is not shown in detail in FIGS. 8 and 10, and its installation position is indicated by a two-dot chain line.

[0044] In this embodiment, as shown in Figures 7 and 8, a liquid fertilizer tank car 40 containing liquid fertilizer LF is located behind the cut injector 30, and is connected to the towing vehicle coupling portion 21 of the tractor 20 using a coupling structure 10, which is the main component of this embodiment. Therefore, the liquid fertilizer tank car 40 is towed by the tractor 20, and the liquid fertilizer LF in the liquid fertilizer tank car 40 is supplied to the upper part of the distribution device 32 via a pressure-feed hose 42.

[0045] When the cut injector 30 is towed by the tractor 20, furrows are made in the field by furrow making rollers 36, . . . , 36 and cutters 37, . . . , 37 provided in front of each discharge injector 35, . . . , 35.

[0046] The liquid fertilizer LF evenly distributed inside the distribution tube 20 of the distribution device 32 is passed through multiple supply hoses 33,...,33 and sprayed into the furrows of the field from each of the discharge injectors 35,...,35 installed at the ends of the hoses, as shown by dotted lines in Figures 8 to 11.

[0047] Therefore, the liquid fertilizer LF flows evenly through each supply hose 33, so that the liquid fertilizer can be evenly spread over the soil in the field. Moreover, the rollers 38,...,38 provided behind each discharge injector 35, cover the top of the furrows with soil, so that the liquid fertilizer LF is sealed within the soil, preventing the dispersion of bad odors.

[0048] Next, the operation of the connecting structure 10 of this embodiment will be described with reference to the drawings. As shown in FIG. 9, the connecting structure 10 of this embodiment is made up of the first connecting member 11a and the second connecting member 11b, which have been described with reference to FIGS. When the connecting structure 10 of this embodiment is connected to the towing vehicle connecting portion 21 of the tractor 20, first, the swinging of the first connecting member 11a and the second connecting member 11b is stopped and locked by the swing lock devices 18,18. Next, the first connecting member 11a is inserted between the left and right guides 17, 17 attached to the main frame 31 of the cut injector 30, and the front end of the first connecting member 11a is connected to the towing vehicle connection portion 21 of the tractor 20.

[0049] Next, the rear end of the second connecting member 11b is connected to the connecting portion 41 of the liquid fertilizer tank car 40. Thereafter, the swing lock devices 18, 18 are unlocked to allow the second connecting member 11b to swing relative to the first connecting member 11a. At this time, the swing range of the second connecting member 11b relative to the first connecting member 11a is restricted to a bending angle α by the stopper 13, as shown in Fig. 4. Moreover, since the left and right swing of the first connecting member 11a at the towing vehicle coupling portion 21 of the tractor 20 is restricted to a small amount relative to the forward movement direction of the tractor 20 by the left and right guides 17, 17, the swing range of the liquid fertilizer tank truck 40 relative to the forward movement direction of the tractor 20 is restricted to a bending angle θ, as shown in Fig. 2.

[0050] In this embodiment, when the cut injector 30 is provided at the rear of the tractor 20 and the liquid fertilizer tank car 40 is placed behind this cut injector 30, it is desirable that the bending angle θ be 40 to 45° so that the liquid fertilizer tank car 40 can turn smoothly without interfering with the cut injector 30.

[0051] In this embodiment, since the cut injector 30 is provided at the rear of the tractor 20, the connecting structure 10 connecting the connecting portion 41 of the liquid fertilizer tank vehicle 40 arranged behind the cut injector 30 and the towing vehicle connecting portion 21 of the tractor 20 becomes longer.

[0052] If the connecting structure 10 were the same as in the past, there would be no problem if the liquid fertilizer tank vehicle 40 followed the tractor 20 when it moved forward in a straight line, but when the tractor 20 turned, the turning radius of the liquid fertilizer tank vehicle 40 would be large. Moreover, the cut injector 30 is large, so the connecting structure 10 would be long. Furthermore, the liquid fertilizer tank vehicle 40 is large because it is equipped with a tank for storing liquid fertilizer, so the turning radius is large. Therefore, in order to set up the tractor 20 so that it can turn and spray fertilizer at a specified location, a wide area for turning is required and it takes time, which reduces work efficiency.

[0053] On the other hand, in the connecting structure 10 of this embodiment, the multiple connecting members 11,...,11 swing left and right at the joints 12,...,12, so the turning radius of the liquid fertilizer tank car 40 is small. Moreover, since the swing range of the multiple connecting members 11,...,11 is restricted, the turning radius of the liquid fertilizer tank car 40 is such that it does not interfere with the cut injector 30. As a result, work efficiency is improved.

[0054] The operation of the connecting structure 10 of this embodiment will be described when it is basically composed of n connecting members 11 and (n-1) joint portions 12. In reality, it is not the case that the more connecting members 11 there are, the better. Rather, since the structure becomes complicated as the number of connecting members 11 increases, it is desirable to have the minimum number of connecting members 11, . . . , 11 that obtains the maximum effect. For example, when the connecting structure 10 is composed of four connecting members 11,...,11 and three joints 12,12,12 connecting the front and rear connecting members 11,11 to each other, it is desirable to restrict the left-right swing of the first connecting member 11a connected to the towing vehicle connecting portion 21 of the tractor 20 to a small value by the above-mentioned guides 17,17. Furthermore, the swing range of each of the front and rear connecting members 11,11 to each other is restricted to a bending angle α by the stopper 13. Note that the bending angle α at each of the joints 12,12,12 may be the same or different.

[0055] As described above, even if the connecting structure 10 is made up of a plurality of connecting members 11, ..., 11, by forming stoppers 13, 13 that regulate the swinging range between the front and rear connecting members 11, 11, the bending angle α between the front and rear connecting members 11, 11 changes little by little, so that the liquid fertilizer tank truck 40 can turn smoothly.

[0056] Furthermore, even if the bending angle α of the multiple connecting members 11,...,11 is different between the front and rear connecting members 11,11, the final bending angle θ of the liquid fertilizer tank truck 40 with respect to the forward direction of the tractor 20 is set to 40 to 45° as described above, so that the liquid fertilizer tank truck 40 can turn smoothly without interfering with the cut injector 30. [Industrial Applicability]

[0057] INDUSTRIAL APPLICABILITY The present invention is applicable in a wide range of fields, such as the agricultural machinery manufacturing and sales industry, agriculture in general, dairy farming, and livestock farming. [Explanation of symbols]

[0058] 10 Connection structure 11 Connection member 11a: first connecting member; 11b: second connecting member 12 joint portion 12a bearing portion 12b Vertical shaft 13, 13a, 13b Stopper 14a Upper flange portion 14b Lower flange portion 15a Upper flange portion 15b Lower flange portion 16 Side plate 17 Guide 18 Swing lock device 18a Lock arm 18b Lock hole 18c First base 18d Second base 18e Lock bolt 18f Screw hole 18g 3rd base 18h screw hole 20 Agricultural tractor (tractor) 21 Tractor coupling 30 Work machine (cut injector) 31 Main frame 31a Connection part 32 distribution device 33 supply hose 34 injector support member 34a actuator 35 Discharge injector 36 Grooving roller 37 Cutter 38 Roller 39 Injector-related mechanisms 40 Towed equipment (liquid fertilizer tank truck) 41 Connection part 42 Pressure hose

Claims

1. A coupling structure for an agricultural towing vehicle, comprising: a working implement at the rear of the agricultural towing vehicle; a towed device disposed behind the working implement; and the towed device is coupled to a towing vehicle coupling section provided at the rear of the agricultural towing vehicle, so that the towed device is towed together with the working implement by the agricultural towing vehicle, The coupling portion of the agricultural towing vehicle and the coupling portion of the towed device are formed by a coupling structure in which a plurality of coupling members are coupled to each other by joints that can swing in the left-right direction, and the joints are one or more in number, A coupling structure for an agricultural towing vehicle, characterized in that the swinging range of a plurality of coupling members caused by the traveling of the agricultural towing vehicle is restricted so that the towed device does not interfere with the work machine.

2. 2. The coupling structure for an agricultural tractor according to claim 1, wherein the plurality of coupling members are formed with stoppers that regulate a range of swing between the front and rear coupling members.

3. 3. The coupling structure for an agricultural tractor according to claim 1, wherein the bending angle of the towed device relative to the forward direction of the agricultural tractor is 40 to 45 degrees.

4. 4. A coupling structure for an agricultural tractor according to claim 1, 2 or 3, wherein the plurality of coupling members are formed with a swing lock device for stopping and releasing the swinging of the front and rear coupling members relative to each other.

5. 5. A connecting structure for an agricultural towing vehicle as described in claim 1, 2, 3 or 4, characterized in that the connecting member connected to the towing vehicle connecting portion among the plurality of connecting members restricts the left-right swinging relative to the forward movement direction of the agricultural towing vehicle to a small extent.

6. 2. The coupling structure for an agricultural towing vehicle according to claim 1, wherein the working machine is a liquid fertilizer spraying device, and the towed machine is provided with a tank for storing liquid fertilizer to be supplied to the liquid fertilizer spraying device.

Images