JP4983250B2 - External hydraulic take-out device for tractor - Google Patents

Description

  The present invention relates to an external hydraulic pressure take-out device for a tractor, and to an assembly structure of an operation lever.

There are various working machines to be mounted on the tractor, for example, an external hydraulic pressure take-out device provided with a plurality of hydraulic valves for external working machines for operating the front loader (Patent Document 1,), before and after the operation lever arranged on the side of the cockpit The first hydraulic valve is operated by a reciprocating operation to move the loader up and down, and the second hydraulic valve is operated by a left and right reciprocating operation to adjust the inclination angle of the bucket.
JP 2004-124503 A

  However, foreign objects can easily enter the control lever, and because it is located on the side of the cockpit, when the front loader operation is interrupted and the vehicle is traveling, the knee and legs are in contact. As a result of the lever moving unexpectedly and operating the hydraulic valve, each part of the front loader operates unexpectedly, which is dangerous.

In view of the above, the invention described in claim 1 is provided with a hydraulic cylinder mechanism (10) that controls the lifting and lowering of the working machine (8) that is mounted on the machine body and a hydraulic cylinder mechanism (11) that controls the operation of the tip working unit. An external hydraulic valve (61, 62) for supplying or discharging pressure oil is provided for each of these hydraulic cylinder mechanisms (10, 11), and one of the external hydraulic valves (61, 62) is provided with one of the external hydraulic valves (61, 62). ) Spool (61a) is interlocked by a swing operation around a predetermined swing center (A) of a single operation lever (65), and the spool (62a) of the other external hydraulic valve (62) is connected to the operation lever ( 65), and the external hydraulic valves (61, 62) are arranged below the passenger step (70), and the operation lever (65). The support part of It is comprised in the housing | casing (72) fixed to the part ranging from a step (70) to a fender (71), a boot (77) is fitted by the upper surface opening part of the said housing | casing (72), and an operation lever (65 ), And a lock means (80) for fixing the swing operation of the operation lever (65) is provided between the operation lever (65) and the fuselage side fixing portion, and the lock means (80 ) Has an engagement hole (81a) that engages with a lock pin (82) that urges the driven member (81) that operates integrally with the operation lever 65 from below to above, of the operation lever (65). An external hydraulic pressure take-out device for a tractor provided at a position opposed to the intersection (c) of different swing centers (a) and (b) with the operation lever 65 interposed therebetween .

  A position where the engagement hole (81a) is opposed to the intersection (c) of the different swing centers (a) and (b) of the operation lever (65) with the operation lever 65 interposed therebetween, that is, the intersection (c) It is provided in the position far from. Therefore, in the locked position, the swing displacement by the operation lever (65) is a relatively large displacement, and therefore the amount of movement of locking or unlocking is large, so that fine accuracy is not required, and versatility of assembly accuracy is accommodated. This is advantageous for design and assembly.

  According to the first aspect of the present invention, the external hydraulic valve (61, 62) is disposed below the passenger step (70), and the support portion of the operating lever (65) extends from the step (70) to the fender (71). ) Is configured in a casing (72) that is fixed to a portion extending over the upper portion of the casing (72), and a boot (77) is fitted into the upper surface opening of the casing (72) to cover the base side of the operation lever (65). Therefore, the boots 77 are fitted into the upper surface opening of the casing 72 to cover the base side of the operation lever 65, thereby preventing foreign matter from entering.

In addition to the above, when configured as described above, when moving the tractor without using an external work machine such as a front loader, the locking means (6) is operated to move the operating lever (65) in the front / rear / right / left direction. Since the movement is restricted, even if an operator's knee or the like unexpectedly contacts the operation lever 65, the movement of each part of the external work machine can be prevented without interlocking with the hydraulic valve, thereby preventing danger.

  Since the lock means 80 is configured to maintain pin engagement with a lock operation from the side of the machine body with respect to a member that operates integrally with the operation lever 65, the lock means 80 can be implemented at low cost, and in the locked position, the lock by the operation lever 65 can be achieved. Since the dynamic displacement is relatively large, the amount of movement for locking or unlocking is large, so the demand for fine accuracy is relaxed and the flexibility of assembly accuracy is easy to use, which is advantageous for design and assembly. is there.

  Embodiments of the present invention will be described below based on the embodiments shown in the drawings. First, in terms of configuration, the tractor shown in FIG. 1 has the engine 1 mounted on the front of the airframe and covered with a bonnet 2, the transmission case 3 is attached to the rear of the airframe, and the cabin 4 is mounted on the upper part thereof. The driver's seat 5 is provided in the cabin 4. Rotational power that has been shifted is transmitted to the rear wheel 6 and the front wheel 7 via the transmission in the transmission case 3.

  A vertical frame 9 for the front loader 8 is provided on the side portion of the machine body, and a loader frame 8B that supports the boom 8A of the front loader 8 so as to be movable up and down can be mounted. The front loader 8 is provided with a tip working portion such as a bucket 8 </ b> C at the tip portion so as to be rotatable up and down. A hydraulic cylinder mechanism 10 for raising and lowering the boom 8A is provided between the loader frame 8B and the boom 8A, and a bucket hydraulic cylinder for adjusting the angle of the bucket 8C between the central curved portion of the boom 8A and the bucket 8C. A mechanism 11 is provided.

  The hydraulic cylinder mechanisms 10 and 11 are controlled by front / rear and left / right operations of an operation lever 65 provided on the right side of the cockpit 12 in the cabin 4. Reference numeral 13 denotes a lift arm for raising and lowering a work machine attached to the rear part of the machine body.

  In FIG. 2, the mission case 3 is composed of a front mission case 3A and a rear mission case 3B. In the front mission case 3A, a main clutch portion 19, a forward / reverse switching mechanism 20, and a main transmission mechanism 21 are arranged in this order. The rear transmission case 3B is provided with an auxiliary transmission mechanism 22 and a rear wheel differential mechanism 23. A PTO transmission shaft 24 part and a front wheel transmission shaft 25 part are arranged across the front and rear transmission cases 3A and 3B.

  The front side of the front transmission case 3A is formed in a clutch housing case 3s to house the clutch portion 19. The output shaft 28 of the engine 1 and the input shaft 29a of the double shaft form coaxial with the output shaft 28 are coaxial. 29b, and the outer input shaft 29a is interlocked with the clutch 19a. The inner input shaft 29b includes a gear 30 that extends to the rear and interlocks with the PTO transmission shaft 24.

  The forward / reverse switching mechanism 20 includes a clutch shaft 32 (output shaft) having a function as an output shaft and an intermediate interlocking shaft 34 parallel to the clutch shaft 32, and the rear end gear 31 of the input shaft 29 a is connected to the intermediate interlocking shaft 34. It meshes with the intermediate interlocking gear 34a. The intermediate interlocking gear 34a interlocks with the first input gear 33 that is loosely fitted to the clutch shaft 32, and interlocks the clutch shaft 32 in the forward direction with the engagement operation of the forward clutch 20F. Of the intermediate interlocking gears 34 a and 34 b provided on the intermediate interlocking shaft 34, a counter shaft 35 provided with a reverse counter gear 35 a meshing with the intermediate interlocking shaft 34 b is arranged, and meshed with the reverse counter counter shaft 35 a and engaged with the clutch shaft 32. The loosely fitted second input gear 36 is interlocked and the clutch shaft 32 is reversely interlocked with the reverse clutch 20R.

  A main transmission shaft 40 of the main transmission mechanism 21 is connected to the rear portion of the clutch shaft 32 coaxially. The main transmission mechanism 21 is changed to 1-4 by continuously changing the meshing gear groups 41a, 41b, 41c, 41d arranged between the main transmission shaft 40 and the main transmission output shaft 41 arranged in parallel. It is the structure which can select the speed gear stage. The main transmission output shaft 41 is configured to obtain the fourth speed, the third speed, the second speed, and the first speed from the front side by a combination of each gear group.

  The drive shaft 43 is arranged and configured coaxially with the main transmission output shaft 41. In parallel with the drive shaft 43, there are provided a first auxiliary transmission countershaft 44 and a second auxiliary transmission countershaft 45 that are linked to an output gear 41a provided at the rear end of the main transmission output shaft 41. These shafts 43, 44, 45 The sub-transmission mechanism 22 is configured to shift to low, middle, and high three stages by selecting the front, middle, and rear three positions of the selected sliding gear 46 of the drive shaft 43.

  The pinion 43a at the rear of the drive shaft 43 is configured to interlock with the ring gear 23a of the rear wheel differential mechanism 23. The drive shaft 43 is provided with an output gear 43b, and the front wheel transmission shaft 25 is interlocked via an intermediate transmission gear 47 and an input gear 48 that are loosely supported by the PTO transmission shaft 24. The front wheel transmission shaft 25 is configured to drive the front wheels 7 through a front wheel differential mechanism (not shown).

  Regarding the transmission configuration from the rear wall of the rear mission case 3B to the PTO shaft 50 protruding rearward, the front end side of the PTO transmission shaft 24 from the gear 30 through the gears 51a and 52a of the first and second intermediate shafts 51 and 52. The input gear 24a provided in the system is interlocked. The input gear 24a is linked to the PTO clutch 53, and the rotational driving force of the input gear 24a is transmitted to the PTO transmission shaft 24 as the clutch 53 is engaged and operated.

  A gear switching mechanism 55 is provided between the rear portion of the PTO transmission shaft 24 and the PTO shaft 50 so that a PTO transmission mechanism can be configured as necessary. In the illustrated example, a plurality of shift speeds are not provided, and the sliding gear 55a is turned on and off and the PTO shaft 50 is turned on and off and interlocked.

  Intermediate walls 3a, 3b, and 3c are provided in the middle of the front transmission case 3A, and the clutch shaft 32, intermediate interlocking shaft 34, and counter shaft 35 are arranged on the intermediate walls 3a and 3b for each axis or a plurality of axes. Are supported via shaft support metals 56a, 56b, 56c, 57. In particular, since the metal 57 that supports the rear side of each shaft is configured to support a plurality of shafts together, the forward / reverse switching mechanism 20 can be easily assembled.

  Between the intermediate wall 3b and the intermediate wall 3c, the main transmission shaft 40, the first and second intermediate shafts 51 and 52 for PTO, and the PTO clutch 53 are supported. The intermediate wall 3c includes a metal 58 that supports a plurality of shafts together.

  Each shaft of the main speed change mechanism 21 is disposed across the metal 58 and a metal 59 which is at the boundary between the front and rear transmission cases 3A and 3B and bulges toward the rear transmission case 3B.

  The rear transmission case 3B is formed with intermediate walls 3d and 3e before and after the rear wheel differential mechanism 23. Between the metal 58 and the intermediate wall 3d, mainly the shafts of the auxiliary transmission mechanism 22 are supported, and the intermediate wall 3e. And a PTO shaft 50 is disposed between the rear wall of the case 3B.

  The transmission mechanism of the tractor configured as described above uses the forward / reverse clutches 20F and 20R of the forward / reverse switching mechanism 20 as a hydraulic clutch, and does not require a main clutch operation by adjusting and controlling the clutch pressure with a pressure proportional control valve. The main shift switching can be performed, and the shift operation can be performed smoothly.

3 to 7 show the operation unit around the driver's seat.
First and second external hydraulic valves 61 and 62 for lifting and lowering externally mounted working machines such as a front loader and a midmower are attached to the side surface of the mission case 3 in a superposed manner via a spacer 63. That is, the pressure oil adjusted to a predetermined pressure is supplied to the spacer 63 via a pipe 64 and the first external hydraulic valve 61 and the second external hydraulic valve 62 are supplied to the spacer 63 via the pipe 64. It is the structure which leads to.

  The spools 61a and 62a of the first and second external hydraulic valves 61 and 62 are configured to be able to switch the oil passages inside the valves by sliding along the longitudinal direction of the machine body. The front end portion of 62a and the operating lever 65 that swings back and forth and right and left are connected by link mechanisms 66 and 67 so that they can be operated separately.

  Among the link mechanisms, a link mechanism 66 that interlocks the spool 61a of the first external hydraulic valve 61 includes an L-shaped swing plate 66a that interlocks the spool 61a, a joint ball 66b provided at the end of the swing plate 66a, and an operation. A hook-shaped plate 69 provided integrally with the lever 65, a first support plate 66c fixed to the hook-shaped plate 69 in a suspended manner, a joint ball 66d provided on the support plate 66c, and the two joint balls 66b, 66d are connected. It is composed of a rod 66e and the like, and by operating the operating lever 65 back and forth around the horizontal axis a, the first support plate 66c, the rod 66e and the swing plate 66a can be linked to slide the spool 61a. is there. The first external hydraulic valve 61 includes a cylinder port 61b and a return port 61c, and for example, supplies pressure oil to the hydraulic cylinder mechanism 10 that moves up and down the arm of the front loader.

  On the other hand, the link mechanism 67 interlocking with the spool 62a of the second external hydraulic valve 62 includes a swing plate 67a having a horizontal axis coaxial with the swing plate 66a, a joint ball 67b provided at the end of the swing plate 67a, and the operation. The control lever 65 includes a second support plate 67c provided in a hanging manner on a bowl-shaped plate 69 integral with the lever 65, a joint ball 67d provided on the support plate 67c, a rod 67e for connecting the joint balls 67b and 67d, and the like. By swinging left and right around the front and rear axis, the second support plate 67c, the rod 67e, and the swing plate 67a are interlocked to slide the spool 62a. The second external hydraulic valve 62 includes a cylinder port 62b and a return port 62c, and controls the supply of pressure oil to the hydraulic cylinder mechanism 11 that adjusts, for example, the bucket scooping or discharging angle.

  When the operation lever 65 is swung back and forth around the horizontal axis, the joint ball 66d swings up and down around the joint ball 67d, while the operation lever 65 is swung left and right around the front and rear axis. At this time, the joint ball 67d is fixed with respect to the first and second support plates 66c, 67c and the shaft cores A, B, etc. so that the joint ball 67d swings up and down around the joint ball 66d. Is done.

  The plane including the ball joints 66b and 66d of the link mechanism 66 of the first external hydraulic valve 61 is disposed on a plane orthogonal to the longitudinal direction of the machine body. It is ideal that the ball joint 66b and the outer spherical shell portion with respect to the inner ball portion originally slide two-dimensionally on a plane orthogonal to the axis of the ball portion support shaft. However, the ball joint 66b can absorb the displacement in the longitudinal direction of the airframe by the three-dimensional sliding between the ball portion and the shell portion of the ball joint 66b by swinging around the axis (a), and thus the ball joint 66b. The position of the operation lever 65 can be displaced to the outside in the left-right direction within the allowable angle range of the joint, and it is possible to secure an operator's knee living space.

  The external hydraulic valves 61 and 62 are disposed below the passenger's step 70, and the support portion of the operation lever 65 is configured in a housing 72 that is fixed to a portion extending from the step 70 to the fender 71. In other words, the step 70 is fastened and fixed to the upper surfaces of the support frames 73a and 73b provided to project laterally from the mission case 3, but the housing frame 74 that supports the housing 72 for the operation lever 65 is secured by the bolts 75 and 75. It is tightened together. One side wall surface of the housing 72 is bolted to the upper bent portion 74 a of the housing frame 74, and another side wall surface is bolted with an L-shaped metal fitting 76 fixed by the above-described bolts 75 and 75 for fastening. ing. A boot 77 is fitted into the upper surface opening of the housing 72 to cover the base side of the operation lever 65, thereby preventing entry of foreign matter.

  A horizontal plate 78 fixed inward (toward the machine body) is provided in the middle of the upper bent portion 74a to constitute a lock means 80 for the operation lever 65. The locking means 80 is intended to avoid a risk that an external working machine is unexpectedly operated due to unexpected contact with a part of the body, for example, a leg or the like, during non-working, and the driven member 81 integrated with the operation lever 65. (In the example shown, the hook-shaped plate 69) is provided with an engagement hole 81a, and the horizontal plate 78 side is provided with a lock pin 82 provided so as to be movable in the vertical direction as a longitudinal direction. The lock pin 82 that is normally urged by the spring 83 in the unlocking direction is provided with a lock lever 84 so as to extend outward from the middle part of the lock pin 82. The upper bent portion 74a of the housing frame 74 is formed with a guide hole 85 for the lock lever 84 so that the locked state can be maintained. The guide hole 85 includes a connecting portion 85c that connects the vertical movement portion 85a and the lock portion 85b to the left and right, and the operation arm 84 can be locked or unlocked by an operation from the side of the machine body.

  The lock means 80 has an engagement hole 81a that engages with a lock pin 82 that urges a driven member 81 (a bowl-shaped plate 69) that operates integrally with the operation lever 65 from below to above. Are provided at a position where the intersection (c) of the swing centers (b) and (b) differing with respect to each other across the operation lever 65 when not operated, that is, at a position far from the intersection (c) in FIG. . Therefore, in the locked position, the swing displacement by the operation lever 65 is a relatively large displacement, so that the amount of movement for locking or unlocking is large, so that fine accuracy is not required, and flexibility in assembly accuracy is available. Since it is easy, it is advantageous for design and assembly.

  When configured as described above, when the tractor is moved and traveled without using an external work machine such as a front loader, the operation is performed by operating the lock lever 84 and engaging the lock pin 82 with the engagement hole 81a. The movement of the lever 65 in the front-rear and left-right directions is restricted, and even if an operator's knee or the like accidentally contacts the operation lever 65, the movement of each part of the external work machine can be restricted without interlocking the hydraulic valve to prevent the above-mentioned danger. . The lock means 80 is configured to maintain the pin engagement with the lock operation from the side of the machine body with respect to the member that operates integrally with the operation lever 65, so that the cost can be reduced.

A side view of a tractor. The sectional side view which shows the transmission structure in a mission case. The side view of the principal part. The front view of the principal part. The enlarged side view (A) of a principal part and the figure (B) which show a guide hole. The enlarged front view of the principal part. The enlarged plan view of the principal part.

8 Front loader (work machine)
DESCRIPTION OF SYMBOLS 10 Boom hydraulic cylinder mechanism 11 Bucket hydraulic cylinder mechanism 61 1st external hydraulic valve 62 2nd external hydraulic valve 65 Operation lever 70 Passenger step 71 Fender 72 Case 77 Boot 80 Locking means 81 Driven member 81a Engagement hole 82 Lock pin 83 Spring 84 Lock lever 85 Guide hole A (front / rear) swing center B (left / right) swing center C Intersection

Claims (1)

A hydraulic cylinder mechanism (10) that controls the lifting and lowering of the working machine (8) mounted on the machine body and a hydraulic cylinder mechanism (11) that controls the operation of the tip working unit are provided, and these hydraulic cylinder mechanisms (10, 11) are provided. An external hydraulic valve (61, 62) for supplying or discharging pressure oil is provided, and the spool (61a) of one of the external hydraulic valves (61, 62) is connected to a single operating lever (61). 65) is interlocked by a swing operation around a predetermined swing center (b), and the spool (62a) of the other external hydraulic valve (62) is swung around a different swing center (b) of the operation lever (65). The external hydraulic valve (61, 62) is disposed below the passenger step (70), and the support portion of the operation lever (65) is moved from the step (70) to the fender (71). Is configured in the housing (72) in which is fixed to the portion over the the upper opening of the housing (72) and configured to cover the proximal side of the boot (77) Mate with the operating lever (65),
A lock means (80) for fixing the swing operation of the operation lever (65) is provided between the operation lever (65) and the fuselage side fixing portion, and the lock means (80) is integrated with the operation lever 65. The engaging hole (81a) that engages the lock pin (82) that urges the driven member (81) that operates from the lower side to the upper side is provided with a different swing center (b) (b) of the operating lever (65). ) An external hydraulic pressure take-out device for the tractor provided at a position facing the intersection (c) of the operation lever 65 with respect to the intersection (c) .

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