PTO clutch for work vehicle and operating apparatus for same

Abstract

A PTO clutch for a work vehicle and an operating structure for the PTO clutch includes: a PTO clutch having a clutch member and receiving drive power from an engine;a clutch control mechanically coupled to the clutch member for manually operating the PTO clutch via the clutch member;a PTO brake disposed downstream of the PTO clutch with respect to a direction in which power is transmitted, the PTO brake being movable to a braking position in association with a clutch disengaging operation of the clutch member; anda control retaining device for retaining the clutch control at a clutch disengaging position.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a general side view of a tractor,

FIG. 2 is a side view in vertical section showing a transmission construction,

FIG. 3 is a side view showing a gear train included in the transmission construction,

FIG. 4 is a side view in vertical section showing a PTO clutch under a clutch engaged condition,

FIG. 5 is a side view in vertical section showing the PTO clutch under a clutch disengaged condition,

FIG. 6 is a side view showing a PTO clutch operating construction under the clutch engaged condition,

FIG. 7 is a side view showing the PTO clutch operating construction under the clutch disengaged condition,

FIG. 8 is a front view in vertical section showing the PTO clutch operating construction, and

FIG. 9 is a plan view showing a further embodiment of an control retaining means included in the PTO clutch operating construction.

Claims

1. A PTO clutch for a work vehicle and an operating structure for the PTO clutch, comprising: a PTO clutch having a clutch member and receiving drive power from an engine;a clutch control mechanically coupled to the clutch member for manually operating the PTO clutch via the clutch member;a PTO brake disposed downstream of the PTO clutch with respect to a direction in which power is transmitted, the PTO brake being movable to a braking position in association with a clutch disengaging operation of the clutch member; andcontrol retaining means for retaining the clutch control at a clutch disengaging position.

2. The PTO clutch and its operating structure according to claim 1, wherein said clutch member and said clutch control are operatively coupled with each other via a link mechanism; and said clutch control is urged by said control retaining means, across a dead point, in a direction toward a clutch engaging position and in a direction toward a clutch disengaging position, respectively.

3. The PTO clutch and its operating structure according to claim 2, wherein said PTO brake is fixed integrally to said PTO clutch; and said PTO brake is urged in a direction toward a braking position, by a spring interposed between said clutch member and said PTO brake.

4. The PTO clutch and its operating structure according to claim 3, further comprising a PTO mode selecting mechanism provided downstream of said PTO brake with respect to the power transmitting direction, said PTO mode selecting mechanism being capable of selectively providing a first transmission mode for transmitting PTO power only to a rear PTO shaft, a second transmission mode for transmitting the PTO power only to a mid PTO shaft and a third transmission mode for transmitting the PTO power to both the rear PTO shaft and the mid PTO shaft.

5. The PTO clutch and its operating structure according to claim 2, wherein said control retaining means is incorporated within said link mechanism.

6. The PTO clutch and its operating structure according to claim 1, further comprising: a rear PTO shaft projecting at a rear portion of a vehicle body and a mid PTO shaft projecting at a lower portion of the vehicle body, both on a downstream side of said PTO brake in the power transmitting direction.

7. The PTO clutch and its operating structure according to claim 1, further comprising a one-way clutch, disposed at a position upstream of said PTO clutch, for allowing advance rotation of a portion of transmission downstream with respect to the one-way clutch.

8. A PTO transmission structure for a tractor, having a rear PTO shaft provided at a rear portion of a vehicle body and a mid PTO shaft at a lower portion of the vehicle body, the structure comprising: a PTO transmission shaft receiving power from an engine;a PTO mode selecting mechanism for selecting output modes to said rear PTO shaft and said mid PTO shaft;a one-way clutch disposed upstream of said PTO mode selecting mechanism with respect to a direction in which power from the engine is transmitted; anda PTO clutch disposed upstream of said PTO mode selecting mechanism.

9. The tractor PTO transmission structure according to claim 8, wherein said one-way clutch is disposed upstream of said PTO clutch.

10. The tractor PTO transmission structure according to claim 9, wherein said one-way clutch, said PTO clutch and said PTO mode selecting mechanism are disposed coaxially and in succession.

11. The tractor PTO transmission structure according to claim 10, further comprising a PTO brake disposed downstream of said PTO clutch, wherein said PTO brake is configured to be activated to perform braking operation in association with a clutch disengaging operation of a clutch member included in said PTO clutch.

12. The tractor PTO transmission structure according to claim 10, wherein said PTO clutch and said PTO mode selecting mechanism are supported to a common transmission shaft.