JPS5921943Y2 - Transmission device for small self-propelled work equipment - Google Patents

Description

[Detailed Description of the Invention] This invention relates to a transmission device for a small self-propelled working machine such as a small snow blower or a cultivator.

This type of small self-propelled working machine needs to change its traveling speed depending on the working situation, working conditions, etc., and is therefore equipped with a transmission device.

Various types of transmissions are known, but for this type of small self-propelled work machine, a transmission using a friction disk has been developed for reasons such as simpler structure, reduced weight, and reliable power transmission. There are some equipped with

In other words, in this transmission, the circumferential surface of the friction wheel is brought into rolling contact with the side surface of a friction disk that is rotationally driven by a prime mover such as an internal combustion engine, and the circumference of the friction disk is changed by displacing the friction wheel in the diametrical direction of the friction disk. By moving the friction disc to a location where the speed is high and a location where it is slow, or to a location where the speed is reversed, the rotation of the friction disc is changed or reversed using a friction wheel.

However, in this type of transmission, power transmission must be cut off before the friction wheel is displaced in the diametrical direction of the friction disk, and therefore a clutch mechanism is required.

However, the conventional clutch mechanism has a complicated structure and has a problem that it does not meet the above-mentioned objectives of simplifying the structure and reducing weight.

In addition, when a clutch structure and a speed change structure are provided, conventionally these operations are independent, and the structure has a clutch operation lever and a speed change operation lever, which makes operation cumbersome. There were also some glitches.

This invention was developed based on the above-mentioned circumstances, and its purpose was to simplify the structure of the clutch mechanism by creating a transmission mechanism using friction discs and friction wheels, and to allow the transmission to be controlled with a single operating lever. Another object of the present invention is to provide a transmission device for a small self-propelled working machine that is easy to operate due to the clutch operation.

An embodiment of this invention will be described below by applying it to a small self-propelled snow blower shown in FIGS. 1 to 5.

In the figure, reference numeral 1 denotes a vehicle body, and the vehicle body 1 is approximately box-shaped, and houses a transmission 2, which will be described later.

A prime mover 3, such as an internal combustion engine, is placed on the upper surface of the vehicle body 1, and a drive side belt pulley 5 is attached to an output shaft 4 extending from the prime mover 3.

On the other hand, a blower case 6 is provided at the front end of the vehicle body 1 to protrude forward, and a snow removal cover 8 that covers the rear half of the auger 7 is connected to the front end of the blower case 6.

A blower 9 is housed in the blower case 6,
This blower 9 is rotated by a blower rotation shaft 10.

The blower rotating shaft 10 also rotates the auger 7.

The blower rotating shaft 10 is guided into the vehicle body 1, and is provided with a driven belt pulley 11 at its tip.

A belt 12 is passed between the driven belt pulley 11 and the driving belt pulley 5, and therefore the blower 9 and the auger 7 are rotated by the prime mover 3.

The snow accumulated by the auger 7 is guided into the blower case 6, and is ejected from a duct 13 that communicates with the blower case 6 and is led upward.

Note that 14 is a direction changing plate provided at the open end of the duct 13.

A drive shaft 15 is pivotally attached to the vehicle body 1 along the longitudinal direction, and a belt wheel 1 is attached to the front end of the drive shaft 15.
6 is installed.

Another belt 17 is stretched between this belt pulley 16 and the drive side belt pulley 5, and this drive shaft 15 is rotationally driven by the prime mover 3.

A friction disk 18 related to the transmission of the present invention is integrally attached to the rear end of the drive shaft 15.

A circumferential side surface of a friction wheel 19 is pressed against one side surface, that is, the rear surface, of the friction disk 18 so as to be movable toward and away from the friction wheel 19 and movable from the rear surface thereof.

This friction wheel 19 has a friction material (not shown) such as a rubber material attached to its circumferential surface by baking or other means, and is spline-engaged with a driven shaft 20 horizontally suspended in the left-right width direction of the vehicle body 1. , can move along the axial direction on this driven shaft 20.

When this friction wheel 19 is displaced along the driven shaft 20, the friction wheel 19 changes its rolling contact position with the friction disk 18, and therefore rolls into contact with the friction disk 18 at a position where the circumferential speed has changed, so that the friction disk The rotation of 18 is transmitted to the driven shaft 20 by changing the speed.

In FIG. 3, the position of Pl is set to be the first forward speed, the position of P2 is set to the second speed, the position of P3 is set to the third speed, and the position of P4 is set to be the reverse speed.

Both ends of the driven shaft 20 are rotatably supported by both ends of a substantially U-shaped swing frame 21 that is horizontally suspended in the width direction of the vehicle body 1, and this swing frame 21 supports the driven shaft. It is swingably attached to the vehicle body 1 at a position offset from the pivot point 20.

That is, support shafts 22a and 22b are provided protruding from the side wall of the vehicle body 1, and these support shafts 22a.

22b, both U-shaped ends of the swing frame 21 are rotatably supported.

Therefore, when the swing frame 21 is tilted by means to be described later, the driven shaft 20 is displaced toward the rear of the vehicle body, thereby separating the friction wheel 19 from the friction disk 18.

Note that one support shaft 22b is provided to protrude from a gearbox 23 formed on one side wall of the vehicle body 1.

One end of the driven shaft 20 is introduced into this gearbox 23, and a first small gear 24 is attached to this introduction end.

This small gear 24 meshes with a large gear 25 housed in the gearbox 23, and this large gear 25 is connected to the second small gear 2.
6 are designed to rotate together.

The second pinion 26 meshes with a gear 28 of an axle 27 that passes through the gearbox 23.

The axle 27 passes through the vehicle body 1 in the left-right direction and is rotatably supported, and is provided with running mechanisms 29 and 29 at both ends located outside the vehicle body 1 in the left-right direction.

The traveling mechanisms 29, 29 are, for example, crawler traveling devices, and include a drive wheel 30 integrally attached to the axle 27,
A driven wheel 31 arranged at a distance behind this driving wheel 30
The frame is constructed by passing an endless track band, that is, a crawler 32, between the two.

Tires (not shown) may be attached directly to the axle 27 instead of the roller traveling device.

The speed change operation structure of the friction wheel 19 is constructed as follows.

That is, at the rear end of the vehicle body 1, there are a pair of left and right handles 34.
34 extend obliquely upward, and these handles 34.
By operating 34, the steering of this snow blower is changed.

A shift position indicating plate 35 as shown in FIG. 4 is attached between these handles 34,34.

This indicator plate 35 has a shift position regulating hole Q1. Q2. Q3
and Q4 are formed as elongated holes in the front-rear direction, and between the rear ends of these regulation holes Q1 to Q4, these regulation holes Q1 to Q4 are formed.
A communication hole 36 is formed to intersect with Q4 and communicate these.

The above-mentioned shift position regulating hole Q1 is for 1st forward speed, Q2 is for 2nd forward speed, Q
3 is the same third speed and Q4 is reverse.

A speed change operation lever 37 is led out through these regulation holes Q1 to Q4 or the communication hole 36.

The lower end of the gear shift operating lever 37 is connected to a support pin 39 provided at the rear end of a coupling member 38 so as to be rotatable in the left and right direction, and the lower end of the gear shift operating lever 37 is connected to a support pin 39 provided at the rear end of a coupling member 38, and is connected to a support pin 39 provided at the rear end of a coupling member 38, and is connected to a support pin 39 provided at the rear end of a connecting member 38 so as to be rotatable in the left and right direction. An inner wire 40a of the Bowden wire 40 is connected to the connected portion.

The center portion of the connector 38 is attached to a support shaft 41 installed between the bundles 34 and 34 so as to be rotatable in the front and rear direction, and the front end of the connector 38 has an operating rod 4
The upper ends of the two are connected.

The lower end of the actuating rod 42 is connected to the rear end of a connecting rod 44 via a direction changing crank 43.

The connecting rod 44 is guided into the vehicle body 1, and its front end is connected to the swing frame 21.

The connecting rod 44 is always pressed forward by the coil spring 45, and the swing frame 21 is therefore urged to rotate in one direction. It is pressed into contact with the

On the other hand, the inner wire 40a of the Bowden wire 40 is led into the vehicle body 1, and its other end is connected to the rear end of the displacement arm 46.

The rear end portion of the displacement arm 46 is bent in an oval shape, and this bent portion is rotatably attached to a bracket 47 provided on the vehicle body 1 via a support shaft 48.

Therefore, when the rear end of the displacement arm 46 is pulled by the inner wire 40a, the displacement arm 46 is rotatably displaced via the support shaft 48.

A U-shaped connecting fork 4 is attached to the tip of the displacement arm 46.
9, and this connecting fork 49 has a sliding groove 50.50.
It is formed.

These sliding grooves 50,50 are engaged with friction wheels 19.

That is, a ring 51 is rotatably attached to the boss portion 19a of the friction wheel 19, and locking pins 52, 52 are protruded from the ring 51.

These locking pins 52, 52 are connected to the sliding grooves 50, 5.
0 in a slidable manner.

Therefore, the displacement arm 46
When rotationally displaced by the operation of a, the connecting fork 49
is displaced, the friction wheel 19 is displaced in the axial direction of the driven shaft 20.

Further, as shown in perspective in FIG. 5, a locking mechanism 53 is provided between the connecting rod 44 and the displacement arm 46.
is configured.

That is, a lock plate 54 is fixed to the displacement arm 46, and the friction wheel 1 is attached to the lock plate 54.
Lock holes R1, R2, R3 and & are bored to correspond to the respective positions of 9.

The lock holes R1 are arranged so as to be in the first forward speed, R2 in the second speed, R3 in the third speed, and R4 in the reverse position.

On the other hand, a lock crank 55 is disposed corresponding to such a lock plate 54.

That is, a bracket 56 is protruded from the vehicle body 1, and the center portion of the lock crank 55 is rotatably attached to the bracket 56 via a pivot shaft 57.

A lock pin 58 is protruded from the lower surface of one end of the lock crank 55 and faces one of the lock holes R1 to R4, and this lock pin 58 is removably engaged with any of the lock holes R1 to R4. It is supposed to be done.

Further, an engagement groove 59 is formed at the other end of the lock crank 55, and this engagement groove 59 engages with an engagement pin 60 protruding from the connecting rod 44.

Therefore, when the connecting rod 44 is pulled rearward against the coil spring 45, the lock crank 55 rotates via the pivot shaft 57, so that the lock pin 58 is separated from the lock hole R1 or R2-R4. .

The operation of the snow remover with such a configuration will be explained.

The rotation of the prime mover 3 is caused by the drive side belt pulley 5 and each belt 12,
17 and driven side belt pulleys 11 and 16, the blower rotating shaft 10 and the drive shaft 15 are rotationally driven, respectively.

Since the blower rotation shaft 10 rotates the blower 79 and the auger 7, the snow is shoveled in from the snow removal cover 8, and the snow is sprayed by the blower 9 and discharged from the duct 13.

On the other hand, the drive shaft 15 rotates the friction disk 18, and the friction wheel 19 in contact with the end surface of the friction disk 18 is rotated by friction.

The rotation of the friction wheel 19 is then transmitted to the driven shaft 20.

Since the driven shaft 20 rotates the axle 27 via the gears 24, 25, 26, 28, the drive wheel 30 is rotated, thereby rotating the roller 32 to achieve traveling.

When it is desired to change the speed, the speed change operation lever 37 is pulled in the direction of arrow F1 as shown in FIG.

That is, assuming that the shift operation lever 37 is now located in the regulation hole Q3 for the third forward speed, when the shift operation lever 37 is displaced in the direction of arrow F1, the coupling 38 rotates in the direction of arrow A about the support shaft 41. The actuating rod 42 is thus pulled up.

As shown in FIG.
Pull in the direction of arrow B against the

Therefore, the connecting rod 44 rotates the swing frame 21 and displaces the driven shaft 20, which is eccentrically attached to the swing frame 21, as shown in the imaginary line.

Therefore, the friction wheel 19 separates from the friction disk 18 and their contact is broken.

As a result, the rotation of the friction disk 18 is not transmitted to the friction wheel 19, and power transmission is therefore cut off, so that the snow blower stops running.

In other words, this operation becomes a clutch function.

On the other hand, as the connecting rod 44 is moved in the direction of arrow B, the engagement pin 60 of the locking mechanism 53 also moves in the direction of arrow B.
Since the lock crank 55 is moved in the direction, the lock crank 55
It is rotated in the direction of arrow C around .

This rotation causes the lock pin 58 to separate from the lock hole R3 of the lock plate 54 fixed to the displacement arm 46.

Therefore, the displacement arm 46 is released from the restraint by the □ lock pin 58.

Next, the shift operation lever 37 in FIG. 4 is moved in the direction of arrow F2 along the communication hole 36 while being pulled in the direction of arrow F1.

Then, since the speed change operation lever 37 is rotatably supported by the connector 38 via the support pin 39, the speed change operation lever 37 swings in the direction indicated by the arrow.

As a result, the inner wire 40a of the Bowden wire 40 is pulled, and thus the inner wire 40a pulls the rear end of the displacement arm 46, as shown in FIG.

At this time, the displacement arm 46 is in a state where the restraint by the lock pin 58 is released, so that the displacement arm 46 rotates about the support shaft 48 .

The amount of rotation of the displacement arm 46 is changed in accordance with the amount of displacement of the speed change operating lever 37 in the direction of arrow F2.

Such rotation of the displacement arm 46 is caused by the connection fork 49
, is transmitted to the friction wheel 19 via the locking pins 52, 52 and the ring 5, and displaces the friction wheel 19 along the axial direction of the driven shaft 20.

Therefore, the friction wheel 19 can be displaced along the driven shaft 20, that is, in the diametrical direction of the friction disk 18, in accordance with the amount of displacement of the speed change operation lever 37 in the direction of arrow F2.

When the displacement position of the shift operating lever 37 in the direction of arrow F2 is determined, for example, when the shift lever 37 reaches the second forward speed position, that is, the position corresponding to the restriction hole Q2, the shift operating lever 37 is released.

Then, in this state, the friction wheel 19 is at the F2 position, and as the displacement arm 46 is displaced, the lock plate 54 is in a position where the R2 lock hole faces the lock pin 58, so that the shift lever 37 is released, the connecting rod 44 is pressed by the coil spring 45 and returns in the direction opposite to the direction of arrow B, whereby the gear shift lever 37 is moved in the direction opposite to the direction of arrow F1 and enters the restriction hole Q2. On the other hand, since the swing frame 21 is pushed and rotated, the friction wheel 19 moves to the F of the friction disk 18 via the driven shaft 20.
It is pressed against the end face at position 2.

Therefore, the rotation of the friction disk 18 is transmitted to the friction wheel 19 to rotate the driven shaft 20.

At this time, since the rotation peripheral speed of the friction disk 18 at the F2 position is lower than that at the F3 position, a reduced rotation is applied to the driven shaft 20.

On the other hand, when the connecting rod 44 returns in the direction opposite to the direction of the arrow B, the lock crank 55 is returned, and the lock pin 58 is fitted into the lock hole R2 opposite to this, so that the lock plate 54 is moved by the lock pin 58. be restrained.

Therefore, since the displacement arm 46 is locked, the friction wheel 19 is firmly stopped at this position.

As described above, according to the above embodiment, the gear shift operation lever 37
By displacing the connecting rod 4 in the direction of arrow F1, the connecting rod 4
4 to swing the swing frame 21, and thereby the friction wheel 1
Since the friction wheel 9 is separated from the friction disk 18, power transmission is completely cut off when the friction wheel 19 is displaced in the axial direction, and the friction wheel 19 does not rub against the friction disk 18.

Therefore, the end face of the friction disk 18 is not damaged, the friction material baked into the friction wheel 19 is not damaged, and the friction wheel 19 can be smoothly displaced in the axial direction with a relatively small force.

Moreover, such separation operation of the friction wheel 19 can be performed by simply moving the speed change operating lever 37 in the direction of the arrow F1, so handling is extremely easy.

According to the above embodiment, even if the friction wheel 19 is displaced to each shift position, the displacement arm 46 is locked by the locking mechanism 53 to prevent the friction wheel 19 from being displaced in the axial direction.

Therefore, even if the friction wheel 19 is displaced to positions Pl, F2, etc., it will not be displaced in the outer radial direction of the friction disk 18 due to its rolling contact with the friction disk 18.

In particular, in this type of snow remover, when the friction wheel 19 is at the positions P1 and P2, the snow removal work is performed by traveling at low speed, and the friction wheel 19 is at the positions P3 and P2.
When it is located at P1 and P2, it is used exclusively for running, so when it is located at P1 and P2, it is used exclusively for driving.
Although it is easy for the friction wheel 19 to receive the force of moving the friction wheel 19 in the direction of the outer diameter of the friction disk 18, the locking mechanism 53 prevents undesired displacement of the friction wheel 19. It is possible to prevent this and ensure a highly accurate gear ratio.

Further, since the locking mechanism 53 is released and locked by utilizing the displacement of the connecting rod 44 in the direction of the arrow B and the opposite direction, the structure is simplified and the operation is simple.

Note that this locking device is not limited to the above embodiment, and various modifications can be implemented.

That is, in the case of the above embodiment, the lock plate 54 is fixed to the displacement arm 46, and the lock plate 54 is fixed to the displacement arm 46.
4 are formed with lock holes R1 to R4, and a lock pin 58 is formed in the lock crank 55 to constitute the locking device 53. Apart from such embodiments, for example, FIGS. Other embodiments such as those shown in .

That is, in this case, a box 101 is provided on the upper surface of a connecting fork 49 attached to the tip of a displacement arm 46, and a coil is always urged upward by a spring 102 and a coil inside this box 101. A lock pin 103 is housed therein, and this lock pin 103 is made to protrude from the top surface of the box 101.

Also, corresponding to this lock pin 103, the lock crank 1
04 is placed at the tip of the connecting rod 44 in the same manner as described above, and the lower end surface of this lock crank 104 is used as a lock plate 105.

This lock plate 105 is provided with a notched lock hole 106 at only one location.

Further, both side edges of the lock plate 105 are also set at the lock position. In this case, one side edge R1 is at the lock position for 1st forward speed, and the lock hole 106 is at the lock position R2 for 2nd forward speed.
, the other side edge R3 is at the lock position for the third forward speed.

Even in this case, the friction wheel 19 can be locked by the same operation and operation as in the previous embodiment.

However, as mentioned above, the first and second forward speeds are for moving the vehicle body 1 during snow removal work, and at this time a large load is applied to the friction wheel 19, so the friction wheel 19 It attempts to move in the direction.

Therefore, if the lock pin 103 is stopped by the lock plate 105 at the positions R1 and R2, the friction wheel 19
movement can be prevented.

On the other hand, the third forward speed and reverse speed are not used for snow removal work, so a large load is not applied to the friction wheel 19, and the movement of the friction wheel 19 is small, so the lock pin 103 is restrained at these times. It's something you don't need.

Furthermore, by configuring the locking device 53 at a position close to the friction wheel 19 on the displacement arm 46, the rattling caused by elastic deformation of the displacement arm 46 is reduced, so that the displacement of the friction wheel 19 can be stopped with high precision. It will be possible.

Furthermore, this invention is not specific to snow blowers;
It is possible to implement this method for small-sized working machines such as cultivators.

As described in detail above, this invention moves the friction wheel along the axial direction of the driven shaft and displaces it in the diametrical direction of the friction disk to change the speed of the rotation of the friction disk and output it to the driven shaft. Since the driven shaft is supported by a swinging frame that is swingable with respect to the vehicle body, when this swinging frame is rocked and displaced, the friction wheel approaches and separates from the friction disk, and the power is transferred and In other words, it forms a clutch mechanism.

Such a configuration has a simple structure because the driven shaft only needs to be supported by the swing frame.

Moreover, in the present invention, since the displacement of the swing frame and the movement of the friction wheel are controlled by a single operating lever, the operation is extremely easy.

[Brief explanation of drawings]

Figures 1 to 5 show one embodiment of this invention.
The figure is a perspective view of a small self-propelled snow blower, Figure 2 is a vertical sectional view of the main parts, Figure 3 is a sectional view taken along the line III-III in Figure 2, and Figure 4 is a perspective view showing the operating part. FIG. 5 is a perspective view showing the locking mechanism. 6 to 8 show modified examples; FIG. 6 is a longitudinal sectional view, FIG. 7 is a sectional view taken along the line Vll-Vll in FIG. 6, and FIG. 8 is a perspective view of the locking mechanism. . 1...Vehicle body, 2...Transmission, 3...
... Prime mover, 15... Drive shaft, 17...
...Belt, 18...Friction disk, 19...
... Friction wheel, 20 ... Driven shaft, 21 ...
... Swing frame, 27... Axle, 29...
Traveling mechanism, 35... Gear shift position indication plate, 37...
... Speed change operation lever, 44 ... Connection rod, 46 ... Displacement arm, Q1 to Q4 ...
・Shift position regulation hole, 36...Communication hole.

Claims (1)

[Scope of utility model registration request] A friction disk rotationally driven by a prime mover, a swinging frame that is swingably supported on the vehicle body, and a swinging frame that is pivotally supported by the swinging frame and swings integrally with the swinging frame. A driven shaft is provided along the diameter direction of the disk, and the driven shaft is attached to the driven shaft so as to be movable in the axial direction, but rotate integrally with the driven shaft, and the friction is reduced based on the swinging of the swinging frame. A friction wheel that is removably pressed against the side surface of the disk and transmits the rotation of the friction disk in this pressed state, and mutually different shift position regulating holes provided in the vehicle body and orthogonal to these shift position regulating holes. A shift position indicating plate is provided with a communication hole connecting between the shift position regulation holes, and is operated to be moved to each shift position regulation hole through the communication hole, and is connected to the swing frame and the friction wheel, and is moved to the communication hole. When operated, the oscillating frame is oscillated to separate the friction wheel from the friction disk, cutting off power transmission, and when the oscillating frame is operated, the friction wheel is moved in the axial direction of the driven shaft when moved to each shift position regulating hole. A speed change device for a small self-propelled working machine, characterized in that it is equipped with a speed change operation lever that moves the friction disk in the diametrical direction of the friction disk.