JPH03213713A - Vibration damper for working machine - Google Patents

Abstract

PURPOSE:To suppress vibration so as to heighten the durability of a coupling part by supporting a bearing, for holding a PTO shaft, elastically at the transmission case side through elastic material at the time of connecting the PTO shaft to a PTO output shaft on the transmission case side by a coupling. CONSTITUTION:At the front part in a transmission case 12, the front end of a transmission shaft 30 is rotatably supported at a cylindrical PTO output shaft 42 by a bearing 40. A bearing 78 for holding the front part of an interlocking shaft 74, which is a PTO shaft, is elastically held on the impeller housing 14a side, that is, on the transmission case 12 side. The relative vibration at a spline coupling 75 part between the PTO output shaft 42 and interlocking shaft 74 is thereby restricted. The vibration can be thus suppressed to improve the durability of the coupling part.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a vibration isolating device applied to a working machine in which a PTO shaft can be attached to and detached from a transmission case using a joint such as a spline connection.

(Background of the invention) Self-propelled working machines use PTO (Power
There are conventional devices that allow the output to be taken out. For example, a small tractor with an auger attached to the front, which collects snow by rotating the auger and moves forward while blowing it away from a snow removal chute, has been proposed (for example, Japanese Utility Model Application No. 59-51814 ).

In this type of working machine, engine rotation is divided into a traveling output and a PTO output by a gear mechanism housed in a transmission case, and each output can be connected or disconnected by a clutch. Here, the engine and the transmission case are usually rigidly fixed to the aircraft frame, and the PTO shaft, which is attached to and removed from the transmission case, can be connected through a joint such as a spline connection.

(Problem to be solved by the invention) However, with this conventional device, vibrations of the engine and transmission case are transmitted to the aircraft frame and PTO shaft, while this PTO shaft
The working machine itself driven by the TO axis also vibrates due to the rotating auger and the like. Therefore, there is a problem in that the vibration of the working machine increases due to the vibration between the transmission case and the PTO shaft.

In addition, vibrations are applied to joints such as spline joints that connect the transmission case and PTO shaft from both sides, the transmission case side and the PTO shaft side. The present invention has been developed in view of these circumstances, and provides a work machine that can suppress vibration and increase the durability of the joint that connects the PTO shaft. The purpose is to provide a vibration isolator.

(Means for Solving the Problems) According to the present invention, this object is achieved by
In a working machine in which a PTO shaft for taking out the PTO output can be connected to the TO output shaft by a joint, the PTO
This is achieved by a vibration isolating device for a working machine characterized in that a bearing that holds a shaft is elastically supported on the transmission case side via an elastic material.

(Function) The relative vibration between the transmission case side and the PTO shaft side is caused by this PTO
It is restricted and absorbed by the elastic material that holds the shaft bearing. Moreover, this elastic material acts to align the axes of the PTO output shaft on the transmission case side and the PTO shaft. Therefore, vibrations applied to the joint portion are suppressed and its durability is improved.

(Example) Fig. 1 is an embodiment of the present invention, and is a partially sectional side view of the power transmission system of a small snowmobile, Fig. 2 is a side view of the snowmobile, and Fig. 3 is a front view. It is.

In FIG. 2, reference numeral 10 denotes a body frame, and a transmission case 12 is integrally fixed to this body frame 10. An auger housing 14 that opens toward the front is fixed to the front end of the transmission case 12. An auger 16 is housed within the auger housing 14. This auger 16 includes an auger shaft 20 supported by bearings 18 and 18 (FIG. 3) on the left and right walls of the auger housing 14, and
The auger shaft 20 includes a spiral auger plate 22 fixed to the auger shaft 20. The auger shaft 20 is rotationally driven by a PTO shaft 74, which will be described later.

As shown in FIG. 1, the transmission case 12 includes a front case 12a.
and the rear case 12b, and the rear case 12b
An engine 24 is rigidly fixed to the top surface of the engine. This engine 24 has a vertical rank axis, and its rotation is transmitted to the transmission case 12 through bevel gears 26 and 28 in the rear case 12b.
The power is transmitted to the power transmission shaft 30 that passes back and forth inside.

The rotation of the transmission shaft 30 is transmitted to the axle 32 via a continuously variable transmission using a planetary cone and a worm speed reducer (both not shown). This axle 32 passes through the lower part of the front case 12a from side to side, and has drive sprockets 3 at both ends.
4 (Fig. 2) is fixed. The fuselage frame 10
Also held are a pair of left and right driven sprockets 36 located behind the driving sprocket 34, and a crawler-type running belt 38 is wound around both sprockets 34,36.

The front end of the transmission shaft 30 is attached to a bearing 4 at the front inside the transmission case 12.
0 on a cylindrical PTO output shaft 42.

This PTO output shaft 42 is connected to the front case 1 by a bearing 44.
It is pivotally supported by 2a.

The front end of the PTO output shaft 42 faces forward from the front surface of the front case 12a, and has internal spline teeth formed on its inner peripheral surface.

The rotation of the transmission shaft 30 is transmitted to the PTO output shaft 42 via a wet multi-plate clutch 48 for snow removal and a rubber damper 50. A brake drum 52 is fixed to the outer periphery of the front end of the PTO output shaft 42, and a brake shoe 54 is attached to the outer periphery of the brake drum 52 so as to be able to press against and separate from the brake drum 52. That is, one end of this brake shoe 54 is pivotally supported by an anchor pin 56 shown in FIG. When the upper end of the lever 62 fixed to the externally projecting end of the camshaft 58 is swung back and forth in FIG. 1, the camshaft 58 rotates to bring the brake shoe 54 into contact with and away from the brake drum 52. It is now possible to do so. Here, the camshaft 58 and the clutch 48 are interlocked by a link 64, and when the clutch 48 is disengaged, the brake shoe 54 presses the brake drum 52 to apply a brake to the PTO output shaft 42, and when the clutch 48 is engaged, the camshaft 58 and the clutch 48 are interlocked. The brake is released when the A detailed explanation of this mechanism is given in Japanese Patent Application No. 153513/1983 filed by the same applicant.

In FIG. 2.3, 68 is a handle, the lower end of which is fixed to the rear case 12b of the transmission case 12, and the upper end of which can be held by the operator during work. A traveling clutch lever 70 and a snow removal clutch lever 72 are attached to the handle 68, and the operator can use the lever 70 to remove snow.
By gripping the lever 72, a traveling clutch (disposed on the axle 32, not shown) can be connected.
By grasping the snow removal clutch 48, the snow removal clutch 48 can be connected.

In FIG. 1, 74 is an interlocking shaft serving as a PTO shaft.

The rear end of this interlocking shaft 74 is connected to the PTO output shaft 42 by a spline connection 75, and the front end drives the auger shaft 20 via a worm reducer 76. This interlocking shaft 7
A bearing 78 is attached near the rear end of 4.
8 is held on the transmission case 12 side via an elastic member 80. Here, the rear part of the auger housing 14 is a bottomed cylindrical impeller housing 14a that opens forward, and the rear surface of the impeller housing 14a is fixed to the front surface of the front case 12a of the transmission case 12 with a plurality of bolts 82. A bearing housing 84 is applied from the front to the rear surface of the impeller housing 14a with an elastic member 80 in between, and the outer ring of the bearing 78 is held between the bearing housing 84 and the elastic member 80. The elastic material 80 and the bearing housing 84 are connected to the impeller housing 14a.
Impeller housing 1 by bolt 86 passing through
4a. That is, this bearing 78 is elastically movable slightly with respect to the impeller housing 14a.

Further, an impeller 88 that rotates within the impeller housing 14a is fixed to the interlocking shaft 74. This impeller 88 guides the snow collected by the rotation of the auger 16 to a chute 90 that stands above it and blows it outside.

Therefore, the operator must operate the clutch lever 7 for traveling on the handle 68.
By squeezing the snowmobile 0, the snowmobile can be moved forward, and by squeezing the snow removal clutch lever 72, the auger 16 can be rotated. By rotating the auger 16 while moving forward, snow is collected and blown out of the chute 90 by the impeller 88, making it possible to continuously remove snow. When the lever 70 is released, the snowmobile stops traveling, and when the lever 72 is released, the snowmobile stops traveling.
When the auger 16 is opened, the auger 16 stops.

A bearing 78 that holds the front part of the interlocking shaft 74, which is a TPO shaft, is elastically held on the impeller housing 14a side, that is, on the transmission case 12 side, via an elastic member 80. The PTO output shaft 42 is connected to the engine 24 and the transmission case 12.
At the same time, vibrations caused by the auger 16 and the impeller 88 are transmitted to the interlocking shaft 74. However, this interlocking shaft 74
Since the rear end of the rear end is elastically supported by the bearing 78, relative vibration at the spline connection 75 between the PTO output shaft 42 and the interlocking shaft 74 is restricted. Note that in the present invention, other joints such as a gear joint or a dog joint may be used instead of the spline joint 75.

(Effects of the Invention) As described above, in the present invention, when connecting the PTO shaft to the PTO output shaft on the transmission case side using a joint, the bearing that holds the PTO shaft is elastically supported on the transmission case side via an elastic material. Therefore, relative vibration between the PTO output shaft and the PTO shaft can be suppressed, and the durability of the joint portion can be improved.

[Brief explanation of drawings]

FIG. 1 is a partially sectional side view of a power transmission system of a small snowmobile according to an embodiment of the present invention, FIG. 2 is a side view of the snowmobile, and FIG. 3 is a front view of the snowmobile. 12... Transmission case, 14... Auger housing,
16...Auger, 42...PTO output shaft, 7
5... Spline connection as a joint, 78... Bearing, 80... Elastic material.

Claims (1)

[Scope of Claims] A working machine in which a PTO shaft for taking out PTO output can be connected to a PTO output shaft housed in a transmission case through a coupling, wherein a bearing for holding the PTO shaft is placed on the transmission case side. A vibration isolating device for a working machine characterized by being elastically supported through an elastic material.