JPH0369854A - Running transmission structure of industrial vehicle - Google Patents

Abstract

PURPOSE:To enable smooth transmission of both transmission mechanisms by a method wherein a first clutch-type transmission mechanism is positioned on the upstream side of transmission and a second shift-gear-tye transmission mechanism is positioned on the downstream side of transmission in a such constitution that the shift gear of the second transmission mechanism is first engaged. CONSTITUTION:When a shift gear 35 of a second transmission mechanism 41 positioned on downstream of transmission is to be engaged, transmission toward upstream from the second transmission mechanism 41 is relatively short to a first transmission mechanism so that its inertial weight is small (since the first transmission mechanism is still i neutral state). Therefore difference i number of rotations between the shift gear 35 of the second transmission mechanism 41 and gears 29, 30 to be engaged with is not so large, and difference in number of rotations at the time of engagement is likely to be small thereby permitting the shift gear 35 to be engaged with the gears 29, 30 rather smoothly.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a traveling transmission structure for a working vehicle in which two sets of transmission mechanisms are connected in series.

[Conventional technology]

As for the above-mentioned traveling transmission structure, the first transmission structure on the upper side of the transmission
Both the transmission mechanism and the second transmission mechanism on the downstream side of the transmission,
Some devices are configured as a gear shift type in which the shift gear is slid to engage the gear on the engaged side.

In this case, for example, as disclosed in Japanese Utility Model Application Publication No. 59-196755, the shift gear of the first transmission mechanism on the upper side of the transmission is slid, and then the shift gear of the second transmission mechanism on the lower side of the transmission is slid. There are some that are configured to do so.

[Problem to be solved by the invention]

In the case of the above-mentioned gear shift type, if the rotational speed of the shift gear and the rotational speed of the gear on the engaged side do not match closely, it is difficult for the shift gear to mesh with the gear on the engaged side. The longer the transmission gear or transmission system that engages with the shift gear or the gear on the engaged side, the greater the inertial weight applied to the shift gear or the gear on the engaged side. There tends to be a difference in the rotational speed between the two, and that difference is difficult to close.

Therefore, when the shift gear of the first transmission mechanism is slid in the disclosed structure, the shift gear meshes with the gear on the engaged side relatively easily. This is because the first transmission mechanism is located on the upper transmission side and the transmission system from the main clutch to this shift gear is relatively short, and the second transmission mechanism on the lower transmission side is in the neutral position. The transmission system connected to the gear on the engaged side is also short up to the second transmission mechanism. This is because the inertial weight applied to the gear on the occlusal side is small, so even if the rotation speeds of both gears do not match, the rotation speeds can be matched relatively easily at the start of occlusion.

However, when the shift gear of the first transmission mechanism is engaged with the gear on the engaged side, and then the shift gear of the second transmission mechanism on the lower transmission side than the first transmission mechanism is slid,
This shift gear is difficult to engage with the gear on the engaged side. This is because a relatively large number of transmission members are connected to the shift gear of the second transmission mechanism, from the main clutch through the first transmission to this shift gear, resulting in a large inertial weight.
This is thought to be because the rotation speeds of the shift gear of the second transmission mechanism and the gear on the engaged side are difficult to match.

Here, an object of the present invention is to provide a configuration that allows smooth gear shifting operations when two sets of transmission mechanisms are connected in series.

[Means to solve the problem]

The feature of the present invention is that the traveling transmission structure of a working vehicle is configured as follows. That is, a clutch-type first transmission mechanism that slides a shift member having an engaging portion to engage the engaging portion with an engaging portion of a gear on the engaged side disposed coaxially; a second transmission mechanism of a gear shift type that engages a gear on the engaged side disposed on a separate shaft by sliding the first transmission mechanism so that the first transmission mechanism is located on the transmission upper side of the second transmission mechanism; The two are connected in series, and means is provided for causing the start of engagement of the shift gear in the second transmission mechanism to precede the start of engagement of the shift member in the first transmission mechanism, and the functions and effects thereof are as follows. be.

[For production]

With the configuration as described above, first, the second
When the shift gears of the transmission mechanism engage, the transmission system from the second transmission mechanism to the first transmission mechanism becomes relatively short and its inertia weight becomes relatively small (if the first transmission mechanism is still in neutral) (to be in a state). Therefore, the difference in rotational speed between the shift gear of the second transmission mechanism and the gear on the occlusal side is not very large, and the difference in rotational speed tends to become small during occlusion, so the shift gear and the gear on the occlusal side can be relatively smoothly shifted. bite

When the shift member of the first transmission mechanism on the upper side of the transmission engages after the shift gear of the second transmission mechanism engages, the upper transmission side from the first transmission mechanism is connected to the main clutch or another transmission mechanism. The lower transmission side from the first transmission mechanism is connected to the second transmission mechanism and its lower transmission side, and its inertia weight is also large. As a result, the difference in rotational speed between the shift member of the first transmission mechanism and the gear on the engaged side becomes relatively large, but in a latch type first transmission mechanism, the engaging part of the shift member and the engaging part Since the spacing is set wide (the same applies to the gear on the engaged side), the engaging part of the shift member smoothly engages with the engaging part of the gear on the engaged side, even if the rotation speed difference is relatively large. That's what I do.

〔Effect of the invention〕

As described above, by arranging the clutch type first transmission mechanism on the upper transmission side and the shift gear type second transmission mechanism on the lower transmission side, and arranging the shift gear of the second transmission mechanism to engage first, The dual-speed mechanism enables smooth gear shifting operations, and improves gear shifting operability.

〔Example〕

Embodiments of the present invention will be briefly described below with reference to the drawings.

As shown in Fig. 6, a frame (2) extends rearward from the mission case (1), and the engine (3) is mounted on this frame (2).
A traveling transmission case (5) equipped with wheels (4) at the bottom of 1).
) are connected to each other, and a control handle (6) is provided on the upper part of the mission case (1), thereby forming a walk-behind work machine which is an example of a work vehicle.

Next, to explain the transmission structure of the PTO system in detail, as shown in Figs. 2 and 6, the output shaft (39
) is provided protruding from the mission case (1) side, and P
A TO system input shaft (9) is provided concentrically with the output shaft (39) and protrudes toward the engine (3), and a PTO pulley (8) is fixed to this input shaft (9). The output shaft (39) and the PTO pulley (8) are connected via a multi-plate clutch (7). Furthermore, a PTO shaft (10) is installed in parallel with this input shaft (9), and this PTO shaft (10)
A PTO high speed gear (11) and a PTO low speed gear (■2) are fixed to the O axis (10). On the other hand, a PTO shift gear (13) is fitted onto the human power shaft (9) in a spline structure so as to be slidable.

Therefore, by engaging the PTO shift gear (13) with the PTO high speed gear (11) or the PTO low speed gear (■2), the working device (not shown) connected to the hitch (14) shown in FIG. ) can be shifted to two high and low speeds.

Next, to explain the transmission structure of the running system in detail, as shown in Figs. 1 and 6, the input shaft (17) equipped with the running pulley (16) is located to the right from the center of the mission case (1). It protrudes from the transmission case (1) toward the engine (3) in a deviated state, and this driving pulley (16
) and the PTO pulley (8).
5) is wound.

Inside the mission case (1), a first transmission shaft (20) is installed horizontally, and the first transmission shaft (20) is installed between the inner surface of the mission case (1) on the deviation side of the input shaft (17) and the input shaft (17). The first transmission is a bevel gear (1) on the shaft (20).
9) is fixed, and this bevel gear (19) is connected to the input shaft (17).
) is engaged with the bevel gear (18).

A first shift gear (33) is attached to the first transmission shaft (20) on the opposite side of the human power shaft (17) so as to be slidable with a spline structure. and,
The second transmission shaft (21) and the third transmission shaft (20) are connected to the first transmission shaft (20).
Transmission shafts (22) are arranged in parallel, and a second transmission shaft (21)
A first gear pair (23) and a first transmission gear (24) are fitted on the outside so as to be relatively rotatable, and a convex engagement portion (34
a) a shift member (34) and a second shift gear (
35) is attached with a spline structure so that it can be slid freely. Further, a second gear pair (25) and a second transmission gear (26) are fixed to the third transmission shaft (22), and the first gear pair (23), the second gear pair (25), and the first transmission gear (2
4) and the second transmission gear (26) are engaged with each other.

The third transmission shaft (22) is equipped with an output gear (2) which will be described later.
A third transmission gear (28) that meshes with the third transmission gear (28) is fitted onto the outside so as to be relatively rotatable, and a fourth transmission gear (29) and a fifth transmission gear (30) are fixed to the third transmission gear (28). ing. In this mission case (1), the driving output part (31) is deviated to the right side of the body (to the left in the drawing) and protrudes downward from the lower surface of the mission case (1). A cylindrical output shaft (32) having a spline structure on its inner surface is mounted horizontally in this output part (31), and the output gear (27) is mounted on this output shaft (32).
) is fixed.

With the above structure, when the first shift gear (33) of the first transmission shaft (20) is engaged with the first gear pair (23),
The engaging portion (34a) of the shift member (34) is connected to the first gear pair (
23) or the engaging portion (24a) of the first transmission gear (24), and the second shift gear (35)
By engaging the fourth transmission gear (29) or the fifth transmission gear (30), the power can be shifted to four forward speeds and transmitted to the output shaft (32). Conversely, the first shift gear (33
) is engaged with the second gear pair (25) and by performing a similar operation, the power can be shifted to four reverse gears and transmitted to the output shaft (32).

As described above, the first transmission shaft (20) portion corresponding to the input shaft (17) and the inner surface of the mission case (1) on the side opposite to the deflection side of the input shaft (17), and the second transmission shaft Axis (21)
The first shift gear (33) and the shift member (
34) etc., the first transmission mechanism (40) (forward/reverse and elevation two-stage transmission) is constructed.

Furthermore, the mission case (
1) A second transmission mechanism corresponding to the inner surface and the first transmission mechanism (40)
A second transmission mechanism (41) including a second shift gear (35) is connected between the transmission shaft (21) portion and the third transmission shaft (22).
) (high/low two-stage transmission). As described above, the clutch type first transmission mechanism (40) is arranged in series on the transmission upper side, and the gear shift type second transmission mechanism (41) is arranged in series on the transmission lower side.

The state shown in Figure 1 is the one-wheel driving transmission case (5).
The input shaft (36) is inserted into the output shaft (32), and the traveling transmission case (5) is connected to the left side of the output section (31) in the drawing. In this traveling transmission case (5), an axle (37) is made to protrude from the lower end to the right in the drawing, so that the wheels (4) are located at the left-right center (CL) of the machine body. With the above structure, power from the output shaft (32) is transferred to the input shaft (36) of the traveling transmission case (5),
It is transmitted to the axle (37) via the transmission chain (38).

Further, as shown in FIG. 1, the right side surface (la) of the mission case (1) can be completely opened from the input shaft (17) to the output section (31). Thereby, by removing the right side surface (1a) after removing the driving transmission case (5), inspection and repair of various parts of the driving system inside the transmission case (1) can be easily performed. Then, the third transmission shaft (22) protrudes from the right side surface (la),
A brake (42) is provided on the protrusion.

Next, the slide operation structure of the shift member (34> of the first transmission mechanism (40) and the second shift gear (35) of the second transmission mechanism (41) will be described in detail. As shown in Fig. 3.4.5. On the ceiling (lb) of the mission case (1), there is a gear shift operation case part (43) that protrudes upward on the right side of the fuselage on the front side of the fuselage. The speed change rod (44) is
Rotatable around the axis (Pl), and the axis (Pl)
It is attached so that it can be slid in any direction. A shift lever (45) is connected to a shift rod (44) portion protruding from the rear wall (43a) of the shift operation case portion (43), and this shift lever (45) extends toward the rear of the aircraft. There is.

On the other hand, a first shift shaft (46) and a second shift shaft (47) are located in the left and right direction of the aircraft inside the mission case (1).
is constructed and fixed, and the first and second shift shafts (
46) and (47), a first shift fork (48) and a second shift fork (49>) are slidably fitted on the outside.The first shift fork (48) is connected to the first transmission mechanism shown in FIG. (40), and the second shift fork (49) is engaged with the second shift gear (35) in the second transmission mechanism (41) in FIG.

A first arm (50) is fixed to the speed change rod (44) with a bolt (52), and is inserted into a long hole (48a) of the first shift fork (48) along the longitudinal direction of the aircraft.
The lower end of the first arm (50) is engaged.

Furthermore, the second arm (51) can rotate relative to the speed change rod (44), and the speed change rod (
44), and the lower end of the second arm (51) is engaged in the elongated hole (49a) of the second shift fork (49) along the oblique direction of the fuselage. In addition, as shown in FIGS. 3 and 5, the second arm (
A long groove (51b) along the axis (Pl) is provided in the boss portion (51a) of 51), and a bolt (53) is engaged in this long groove (51b).

Thereby, even if the speed change rod (44) is rotated around the axis (Pl), the second arm (51) is configured not to rotate accordingly.

With the above structure, the gear shift lever (45)
First, slide it in the direction of the axis (Pl).

In this case, the first and second arms (50) and (51) slide together with the speed change rod (44), but the first shift fork (48) is not operated due to the flexibility of the elongated hole (48a). On the contrary, the second shift four (49)
is slid along the second shift shaft (47) by the action of the oblique elongated hole (49a), thereby shifting the second shift gear (35) of the second transmission mechanism (41).
meshes with the fourth transmission gear (29) or the fifth transmission gear (30).

Following this sliding operation in the direction of the axis (Pl), the shift lever (45) is operated to swing around the axis (Pl).

In this case, the first arm (50) swings together with the speed change rod (44), but the second arm (5I) swings together with the bolt (53).
) does not swing due to the engagement action. As a result, the first shift fork (48) is slid along the first shift shaft (46), and the shift member (34) of the first transmission mechanism (40) is shifted to the first gear pair (23) or It engages with the first transmission gear (24).

As described above, the configuration is such that the second shift gear (35) of the second transmission mechanism (41) engages, and then the shift member (34) of the first transmission mechanism (40) engages. be.

In addition, as shown in Figures 4 and 5, the mission case (
1), the first and second shift shafts (4
6), ball (5) to fix (47) in place
4) and a fixing bolt (55).

This fixing bolt (55) is hidden under a handle support base (61), which will be described later, to prevent it from being touched inadvertently.

Next, the first shift gear (
33) slide operation (forward/reverse switching operation) structure will be described in detail. As shown in FIGS. 3 and 4, an operating shaft (56) is supported rotatably around the vertical axis (P2) below the protruding portion of the speed change rod (44) on the rear wall (43a) side. and a pair of operating arms (56a) provided at the upper end of the operating shaft (56) and a forward/reverse lever (not shown).
are connected via a pair of wires (58).

On the other hand, a third shift shaft (59) is installed and fixed in the transmission case (1), and a third shift fork (60) that engages with the first shift gear (33) is installed in the third shift shaft (59).
It is slidably fitted onto the shift shaft (59), and is attached to the operating shaft (59).
The operation arm (56b) fixed to the lower end of the third
It engages with the base of the shift fork (60). With the above structure, the operating shaft (56
) to the right or left and turn the third shift fork (60
) to slide the first shift gear (33).

Next, a handle support stand (6) equipped with a control handle (6) is installed.
For installation in 1), the structure will be explained in detail. As shown in Figures 4 and 5, the ceiling (1b) of the mission case (1)
) is provided with three mounting seats (1c) with screw holes. In the gear shift operation case part (43), the end of the left side of the machine (corresponding to the center side of the ceiling part (1b)) is formed into a stepped recessed part (43b), and a flat handle support base is formed. (61) is installed on the ceiling (lb) with its end inserted into the recessed step (43b).

Then, the handle support base (
61), the spacer (62), the gear shift operation case part (43) part of the recessed step part (43b), and the ceiling part (1b),
■They are fastened together with bolts (63).

The handle support base (61) is directly bolted to the other mounting seat (lc).

Additionally, this walk-behind work machine can be modified to the following types: In other words, the ceiling part (1) of the mission case (1)
b), remove the shift operation case part (43), shift rod (44), etc. provided in the first shift shaft (4
6) and the second shift shaft (47) into the mission case (1
) to protrude laterally outward from the right side surface (1a). In this case, the fixing bolt (55) and ball (54) are removed to make the first and second shift shafts (46), (47) slidable, and the first and second shift forks (48), (
49) respectively to the first shift shaft (46) and the second shift shaft (46).
7) Connect and fix.

Then, a shift operation part (not shown) is attached to the right side surface (1a) of the transmission case (1), and the first and second shift shafts (46) and (47) are slid from this shift operation part. , Types with speed change operation are indicated by reference numerals in the claims section for convenience of comparison with the drawings.
By virtue of this description, the invention is not limited to the structure of the attached drawings.

[Brief explanation of drawings]

The drawings show an embodiment of the traveling power transmission structure for a working vehicle according to the present invention, in which Fig. 1 is a longitudinal sectional front view of the transmission case, Fig. 2 is a longitudinal sectional side view of the vicinity of the PTO system of the transmission case, and Fig. 3 is the transmission case. Fig. 4 is a plan view of the transmission case near the ceiling, Fig. 5 is a longitudinal front view of the transmission case near the ceiling, and Fig. 6 is an overall side view of the walk-behind work machine. It is. (23), (24), (29), (30)...
...Gears on the occlusal side, (23a), (24a)...
... Engagement part of the gear on the occlusal side, (34) ...
・Shift member, (34a)...Engaging portion of shift member, (35)...Shift gear, (40)...
. . . 1st transmission mechanism, (41) . . . 2nd transmission mechanism.

Claims (1)

[Claims] By sliding the shift member (34) having the engaging portion (34a), the engaging portion (34a) is connected to the engaging portion of the engaged gears (23) and (24) arranged coaxially. (23
a), (24a) is engaged with the clutch-type first transmission mechanism (40), and the shift gear (35) is slid to engage the engaged side gears (29), (3) arranged on separate shafts.
0), a gear shift type second transmission mechanism (41
), and the first transmission mechanism (40) is connected to the second transmission mechanism (4).
1) are connected in series so as to be located on the upper side of transmission, and the shift gear (3) in the second transmission mechanism (41) is connected in series.
5) A traveling transmission structure for a work vehicle, comprising means for causing the start of engagement to precede the start of engagement of the shift member (34) in the first transmission mechanism (40).