JPH034063A - Belt type continuously variable transmission - Google Patents

Abstract

PURPOSE:To rotate an output takeoff shaft in no relation to the speed of a wheel or the like by externally fitting the second rotary shaft to the outside of the first rotary shaft to form a double structure in which one of the drive forces for the output takeoff shaft and the wheel or the like is transmitted by the first rotary shaft and the other is transmitted by the second rotary shaft. CONSTITUTION:A variable pulley 3 for a speed change belt A is mounted to an output shaft 2, and the variable pulley 3 comprises a fixed sheave 4 and a variable sheave 5. Drive power of the output shaft 2 is transmitted through the variable pulley 3 from the speed change belt A via a pulley 16 to the first rotary shaft 17 further through a gear 14 and a speed change mechanism 13 to a wheel 12. While the second rotary shaft 18 is provided in the outside of the first rotary shaft 17, and drive power is transmitted through a pulley part 7, provided in the upper end of the fixed sheave 4, to a general belt B and via pulley 19 through the second rotary shaft 18 and a transmission mechanism 15 to an output takeoff shaft 14. Since the pulley part 7 has a fixed pitch diameter, a rotary speed of the output takeoff shaft 14 is not changed even when a car speed of the wheel 12 is changed.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a belt type continuously variable transmission having an output output shaft (hereinafter referred to as a PTO shaft).

(Prior Art) Belt type transmissions have conventionally been used in agricultural machinery such as tillers and management machines, as described in, for example, Japanese Utility Model Application Publication No. 63-171752.

Furthermore, among such belt-type transmissions, one is known that is provided with a PTO shaft for extracting output and driving external equipment.

(Problem to be solved by the invention) However, in such a belt-type transmission, the wheel drive shaft and the PTO shaft are driven by the same transmission mechanism, so when the vehicle speed is changed, the rotational speed of the PTO shaft also changes. It changes and cannot handle a variety of different tasks. Therefore, it is conceivable to provide two transmission mechanisms, but if this is done, the two transmission mechanisms will be disposed, and the transmission itself will become larger.

The present invention has been made in view of the above, and an object of the present invention is to provide a belt-type continuously variable transmission that can rotate a PTO shaft at a constant rotational speed without increasing the size.

(Means for Solving the Problems) The present invention provides a first rotary shaft that drives a drive shaft such as a wheel, and a P
The second rotating shaft that drives the TO shaft is configured using a double shaft structure.

Specifically, a belt is wound between a variable pulley on the driving side and a pulley on the driven side, which are made up of a movable sheave and a fixed sheave, to form a variable pulley mechanism, while A transmission mechanism is constructed by winding a belt between the attached drive-side pulley and another driven-side pulley, and a cylindrical second rotation shaft is rotatably fitted outside the first rotation shaft. The driven pulley of the variable pulley mechanism is attached to one of the first or second rotating shaft, and the driven pulley of the transmission mechanism is attached to the other of the first or second rotating shaft, and further, the first Alternatively, the other of the second rotating shafts is linked to the output output shaft.

(Function) A cylindrical second rotating shaft is located outside the first rotating shaft, and does not take up space. The other of the driving forces of the PTO shaft or the drive shaft is transmitted through the two rotating shafts.

(Example) Examples of the present invention will be described in detail below with reference to the drawings. Incidentally, as shown in FIG. 8, the belt type continuously variable transmission 101 according to the present example has a tiller 10 of a well-known structure as a working machine.
Applies to 2.

In FIG. 1 showing the overall configuration, 1 is an engine, 2 is an output shaft of the engine 1, and a drive-side variable pulley 3 for a speed change belt A is attached to the output shaft 2. The variable pulley 3 is composed of a fixed sheave 4 and a movable sheave 5, and an idling bearing 6 is disposed between the sheaves 4 and 5. Therefore, the general belt B is attached to the upper end of the fixed sheave 4.
A pulley portion 7 for use is formed.

Reference numeral 11 denotes a transmission unit, which includes a transmission mechanism 13 for driving wheels 12 and 12 inside a unit case lla, and a PTO shaft 1.
A rotation mechanism 15 that rotates four times when the shaft is aligned is provided.

The driven pulley 16 of the variable pulley 3 is connected to the first rotating shaft 1
7, and a gear 14 linked to the transmission mechanism 13 is attached to the first rotating shaft 17. Further, a second rotating shaft 18 is rotatably supported on the outside of the first rotating shaft 17 via a bearing 8°8, and a pulley 19 is provided at one end of the second rotating ring 18 on the driven side of the pulley portion 7. A gear 20 to which the rotation mechanism 15 is linked is attached to the other end.

Also, for the belts A and B, tensioners 21.
22 are arranged. Thus, the tensioner 21 on the side of the speed change belt A changes the tension of the belt A in accordance with changes in the pulley pitch diameter of the variable pulley 3. The tensioner 22 on the general belt B side is linked to an operation system (not shown), and has two positions: a 4-movement position where the PTO shaft is pressed strongly against the general belt B, and a 4-movement position where the PTO shaft is not pressed strongly against the general belt B. It is designed to take position.

23, 24 and 25, 26 are bearings, respectively, which are attached to the unit case lla and rotatably support the second rotating shaft 18, the first rotating shaft 17, and the shaft 13a of the 4-speed change mechanism 13 including one PTO shaft. There is.

With the above configuration, the driving force of the wheels 12.12 is transmitted from the engine 1 through the variable pulley 3, the belt A1 pulley 16, the first rotating shaft 17, and the transmission mechanism 13.

On the other hand, from the engine 1, the variable pulley 3, the pulley part 7, the belt A1 pulley 19, the second rotating shaft 18, and the transmission mechanism 15
Through the transmission system, which is different from the transmission system for the driving force of the wheels 12 and 12, the driving force for driving the external equipment is transmitted to the PT.
O axis 1 axis alignment 4 is reached. As a result, the pulley section 7
Since it has a constant pitch diameter, even if the vehicle speed of the wheels 12 and 12 changes due to a change in the pitch diameter of the variable pulley 3, the PT
One O-axis rotates at a constant rotational speed.

In the above embodiment, the pulley portion 7 is formed in a part of the fixed sheave 4, but as shown in FIG.
A pulley 32 for rotating the TO axis is attached, and a pulley 34 on the driven side of the first rotating shaft 17 whose shaft end is composed of three PTO axes is attached to the second rotating shaft 18 for driving the wheels 12 and 12. The pulleys 35 on the driven side may be respectively attached.

The mechanism shown in FIG. 2 is specifically shown in FIGS. 3 to 5.

In the drive-side variable pulley 30, as shown in FIGS. 6 and 7, both the fixed sheave 31 and the movable sheave 36 have a sheave surface 37a that serves as a pulley surface.

The fixed sheave 3 consists of a sheave part 37.38 having a diameter of
While the cylindrical part 40 of 1 is fitted and fixed to the pulley shaft 39,
A cylindrical portion 41 of the movable sheave 36 has a retaining groove 44 that engages with a guide pin 43 that protrudes radially outward from a cylindrical member 42 that is fixed to the pulley shaft 39 . Due to the engagement relationship with the matching groove 44, it is movable only in the axial direction of the pulley shaft 3. The cylindrical member 42 and the movable sheave 36
A sealing material 45.45 is interposed between the cylindrical portion 41 and the cylindrical portion 41.

A mounting member 46 is fitted and fixed to the end of the cylindrical member 42, and a bearing 47 (bearing ) are provided. A roller stand 48 is attached to the bearing 47, and a roller 49 is rotatably supported on the roller stand 48.

On the other hand, a bearing 50 is attached to the cylindrical portion 41 of the movable sheave 36, and a cam member 51 is attached to the outside of the bearing 50. The cam member 51 is provided with a protrusion 52 that is linked to the operating system, and by rotating the cam member 51, the cam surface of the cam member 51 engages with the roller 49 and moves in the axial direction. This allows the pulley pitch diameter to be changed. The belt tensioner 52 rotates against the spring force of the spring 54 so that the tension on the belt A by the tensioner 52 changes in accordance with this change in the pulley pitch diameter.

Further, the tensioner 53 on the general belt B side is linked to an operating lever 57 via a spring 55 and a cable 56, and by operating the operating lever 57, the tensioner 53 on the general belt B side is connected to a three-axis PTO shaft that is strongly pressed against the general belt B. Position P1 and a three-drive position P2 where the three PTO shafts are not pressed strongly against the general belt B are set.

The driven pulley 35 includes a disc-shaped plate part 35b with a plurality of hollow holes 35a interposed therein, a pulley part 35c attached to the outside of the disc-shaped plate part 35b, and a cylindrical part attached to the inside of the plate part 35b. The cylindrical portion 35d is fitted onto the second rotating shaft 18.

Note that 54 is a stop ring of the bearing 50, and 55 is a mounting portion that is attached to an appropriate location to inhibit rotation of the roller stand 48.

Therefore, the driving force for the wheels 12.12 is transmitted from the engine 1 through the variable pulley 31, the belt A1 pulley 35, the second rotating shaft 18, and the transmission mechanism (not shown).

On the other hand, the combined power of the three PTO shafts is transmitted from the engine 1 through the pulley 33, belt B1 pulley 34, and first rotating shaft 17 to an external transmission system that is separate from the transmission system for the driving force of the wheels 12 and 12. A driving force for driving the equipment is transmitted to a PTO shaft that is a part of the first rotating shaft 17. As a result, the pulley 33 has a constant pitch diameter, so even if the vehicle speed of the wheels 12.12 changes due to a change in the pitch diameter of the variable pulley 31, the PTO shaft (first rotating shaft 17) remains at a constant rotation speed. It will rotate.

(Effects of the Invention) Since the present invention is configured as described above, the second concave rotating shaft is located outside the first rotating shaft, and the first rotating shaft drives the PTO shaft or the drive shaft without taking up space. one of the forces, the second
The rotation shaft can transmit the other, and the PTO shaft can be rotated independently of the drive shaft.

[Brief explanation of the drawing]

1 to 7 show embodiments of the present invention, and FIG. 1 is a skeleton diagram of a belt type continuously variable transmission. Figure 2 is a skeleton diagram of a belt-type continuously variable transmission according to another embodiment;
Figures 7 to 7 show the specific configuration of the embodiment shown in Figure 2, Figure 3 is a sectional view of the main part of the belt type continuously variable transmission, Figure 4 is a side view of the variable speed drive system, and Figure 5 is a side view of the variable speed drive system. 6 is a side view of the PTO shaft drive system, and FIGS. 6 and 7 are a partial sectional view and side view of the variable pulley. Fig. 8 is a side view of a general tiller (walking type moving layer a). 1... Engine 2... Output shaft 3. 30... Variable pulley 4. 31...Fixed sheave 5.36...Movable sheave 14.33...PTO shaft (output extraction shaft) 16.
34...Pulley 17...First rotating shaft 18...Second rotating shaft A, B...Belt has a force\2 and 1... - Engine 2 - Output shaft 31] - Variable pulley 31 - Fixed sheave 36 - Movable sheave 33 - PTO shaft (output extraction shaft) 34 - Pulley 17... ...First rotating shaft 18...Second rotating shaft B...Belt "-1"

Claims (1)

[Claims] (1) A variable pulley mechanism is constructed by winding a belt between a variable pulley on the driving side and a pulley on the driven side, which are made up of a movable sheave and a fixed sheave. A transmission mechanism is constructed by winding a belt between a driving pulley and another driven pulley, and a cylindrical second rotating shaft is rotatably fitted outside the first rotating shaft. A double shaft structure is formed, and a driven pulley of the variable pulley mechanism is mounted on one of the first or second rotation shaft.
A belt-type continuously variable transmission, characterized in that a driven-side pulley of a transmission mechanism is attached to the other, and the other of the first or second rotating shaft is linked to an output output shaft.