JPH0348060A - Transmission for industrial vehicle - Google Patents

Abstract

PURPOSE:To improve working efficiency by a method wherein when coupling is completed, a clutch for selecting a counter shaft for a counter shaft coupled at present is disengaged, and a clutch for selecting a counter shaft for a counter shaft whose coupling with a gear is completed is engaged. CONSTITUTION:Gear trains 8 and 9 for forward are disposed on the one 3 of two counter shafts 3 and 4 and gear trains 10 and 11 for reverse on the other 4. In switching between forward and reverse, under a state in which the input shaft 1 side is coupled to the output shaft 2 side through the one counter shaft 3 by means of a control means, a gear to be selected is coupled to the one counter shaft. After the coupling is completed, a clutch 6 for selection of the one counter shaft 3 is engaged, and switching is effected so that a clutch 7 for selection of the one counter shaft 4 is engaged. This constitution effects switching in an extremely short time without engaging and disengaging a clutch during engagement and disengagement of a gear and improves response to gear shifting.

Description

Detailed Description of the Invention (Field of Industrial Application) This invention relates to a transmission device for industrial vehicles such as forklifts, which is particularly compact and has good responsiveness when shifting between forward and reverse gears, or when shifting between forward and reverse gears. The present invention relates to a transmission device in which power transmission between second speeds is not interrupted and delicate forward and reverse operations are possible.

(Prior Art and Problems to be Solved by the Invention) Some large industrial vehicles, such as forklift trucks, are equipped with multi-stage transmissions from the viewpoint of work efficiency. In addition, recently, with the intention of improving work efficiency for industrial vehicles other than large ones,
Vehicles equipped with multi-stage transmissions began to appear (Utility Model Publication No. 60-40847, Japanese Patent Application Publication No. 59-110947).
.

In the case of industrial vehicles such as forklifts, the main work is to transport so-called heavy objects or to frequently move back and forth in a relatively narrow space, so it is necessary to change gears and clutches when shifting between forward and reverse. If it takes a long time to intermittent, the responsiveness when changing direction of travel will decrease. Similarly, if the driving force is temporarily interrupted during a shift between the first and second speeds, the speed before the shift cannot be maintained, resulting in a decrease in work efficiency. For example, in the case of forklifts, etc., there are many operations in which forward and backward movements are performed hundreds or even thousands of times a day, but if this "switching" between forward and backward movements is not performed instantaneously, - This results in a considerable decrease in work efficiency for the whole day. That is, even if one second of lost time occurs during the - times of switching operations, the overall work efficiency for the day will be greatly reduced.

This occurs not only when switching between forward and reverse speeds, but also when switching between the first speed and second speed.

In addition, unlike ordinary cars, industrial vehicles require delicate positioning of objects to be transported, and because they often transport heavy objects, smooth starting is required. In the case of industrial vehicles, the above operation required a high level of skill for the operator due to the configuration of the hydraulic circuit.

By the way, among the above industrial vehicles, small ones are still equipped with a transmission with one forward speed and one reverse speed due to the lack of space and the low absolute vehicle price. The current situation is that there are many.

In this way, a transmission with one forward speed and one reverse speed is good for work in relatively narrow buildings, etc., but when used in places where the transport distance is relatively long, it is necessary to transport heavy objects. Due to the fact that the reduction ratio is set at a fairly high level, the conveyance efficiency is significantly reduced. For this reason, there has been a desire for an industrial vehicle equipped with a multi-stage transmission that can be provided at low cost and can be mounted on small industrial vehicles.

The present invention was made in view of the current situation, and
It has good responsiveness when shifting between forward and reverse gears, no interruption of driving force when shifting between first and second gears, allows delicate operation, and has a compact exterior. The purpose of the present invention is to provide a transmission with a structure that can be installed on small industrial vehicles.

(Means for Solving the Problem) A transmission device for an industrial vehicle according to the first invention has two counter shafts arranged parallel to an input shaft, and an output shaft arranged parallel to these two counter shafts. A counter shaft selection clutch is interposed between the above two counter shafts and the input shaft or between the above two counter shafts and the output shaft to connect and connect these shafts. A gear train for forward movement is arranged, and a gear train for reverse movement is arranged on the other one of the counter shafts, and the gear train meshes with each gear on each of the above counter shafts on the output shaft or input shaft. are arranged so that they can be freely connected and disengaged via a gear selection clutch so that any one of the gears constituting the gear train can be selectively engaged with any gear of the gear train on the counter shaft. When switching between forward and reverse, the next gear to be selected is connected to the countershaft on the unconnected side via the gear selection clutch, and when this connection is completed, the current The present invention is equipped with a control means that performs switching control to turn off the counter shaft selection clutch of the connected counter shaft and turn on the counter shaft selection clutch of the counter shaft for which the gear connection has been completed. Specially designated as Maki.

The industrial vehicle transmission according to the second invention has two counter shafts arranged parallel to the input shaft, an output shaft arranged parallel to these two counter shafts, and the above-mentioned two counter shafts and human power A counter shaft selection clutch is interposed between the shafts or between the above two counter shafts and the output shaft, and is capable of connecting and connecting these shafts to form a half-clutch state. Each first speed gear train for reverse movement is arranged, and each second speed gear train for forward movement and reverse movement is arranged on the other counter shaft, and the above mentioned gear train is arranged on the output shaft or the input shaft. A gear train that meshes with each gear on each counter shaft is configured such that any one gear of each gear constituting the gear train can be selectively meshed with any gear of the gear train on the counter shaft. It is arranged so that it can be connected and disengaged via a selection clutch, and when switching between 1st speed and 2nd speed for forward and reverse,
The present invention is characterized by comprising a control means for controlling the two counter shaft selection clutches to be switched to pass through a half-clutch state, and then to switch from one clutch to the other clutch.

The industrial vehicle transmission according to the third invention has two counter shafts arranged parallel to the input shaft, an output shaft arranged parallel to the two counter shafts, and the two counter shafts and the input shaft arranged parallel to each other. A counter shaft selection clutch is interposed between the shafts or between the above two counter shafts and the output shaft to connect and disconnect between these shafts, and on each of the above counter shafts, on the above output shaft or on the input shaft. A gear train that selectively engages the gears is disposed so as to be freely coupled and disengaged, and a counter shaft selection clutch provided on each of the counter shafts is selectively actuated as appropriate, so that a gear train is selectively engaged with the gears. In a transmission for an industrial vehicle configured to transmit power from an input shaft to an output shaft, the above two counter shaft selection clutches are configured to be operated by a hydraulic circuit equipped with a hydraulic circuit as shown below. It is characterized by

(a), the output side port is connected to the operating hydraulic circuit of the two counter shaft selection clutches, and the input side port is connected to the hydraulic pump side via the throttle valve.
A position type switching valve is installed, Φ), branched from between the throttle valve and the switching valve, and a manual relief valve and ON-OFF operation are controlled by a signal from the control device when switching the switching valve. A solenoid valve that operates repeatedly and whose output side communicates with the reservoir tank side is installed.

(Function) As described above, the industrial vehicle transmission according to the first invention has a forward gear train on one of the two counter shafts and a reverse gear train on the other. By arranging
When switching between forward and reverse movement, the control means connects the gear to be selected to the other countershaft while the input shaft side and the output shaft side are connected by one countershaft,
After this connection is completed, the selection clutch of one of the countershafts is turned OFF and the selection clutch of the other countershaft is turned ON, so the clutch is turned OFF while the gears are engaged. Since there is no need to keep the
It is possible to obtain a transmission device with good responsiveness regarding shifting.

As described above, the industrial vehicle transmission according to the second invention has a first speed gear for forward and reverse movement on one of the two counter shafts, and a second speed gear for forward and reverse movement on the other side. When switching between the first and second speeds, the control means causes the two counter shaft selection clutches to be switched to be in a half-clutch state, and then one of the clutches is turned off. If you operate the other clutch to switch, it will be used when switching between forward and reverse or the first clutch.
There is no interruption in driving force when switching from high speed to second speed.

In the industrial vehicle transmission device according to the first and second inventions, the two counter shafts are disposed parallel to the input shaft, and the two counter shafts are arranged parallel to each other, as described above. By arranging the output shafts parallel to each other and arranging a gear train for shifting between these two counter shafts, the transmission can be housed within the same volume as the conventional one-forward gear and one-reverse gear train. can.

Therefore, in this case, parts such as the same transmission case can be shared with a transmission with one forward speed and one reverse speed.
A multi-stage transmission can be directly installed in the same position (within the space).

Further, when the industrial vehicle transmission device according to the third invention is provided with the hydraulic circuit as described above, the solenoid valve can be turned on and off for a predetermined period of time by the control device during normal gear shifting.
As a result of the clutch being activated and gradually connected, smooth gear changes can be achieved, and when delicate clutch operation is required, the driver can operate the manual relief valve mentioned above to achieve delicate driving conditions. It will be done.

Moreover, since a throttle valve is interposed between the hydraulic circuit including the switching valve, relief valve, and solenoid valve and the hydraulic pump, there is a connection between the hydraulic pump and other hydraulic equipment (for example, a torque converter). The hydraulic pressure can be maintained above a predetermined pressure without affecting the operation of other hydraulic equipment.

(Example) Fig. 1 is a skeleton diagram showing the overall configuration of a torque converter type automatic transmission with two forward and two reverse speeds according to the first invention. This is a transmission device configured as follows.

In FIG. 1, ■ is a human power shaft, 2 is an output shaft, and 34 is a counter shaft arranged parallel to the human power shaft 1 and the output shaft 2. In this embodiment, the input shaft 1 and the output shaft 2 are coaxially arranged.

5 is a torque converter, which connects the input shaft 1 and the crankshaft C.
It is interposed between.

A friction plate type counter shaft selection clutch 6 is interposed between the input shaft 1 and the counter shaft 3 to connect and disconnect power between the two shafts. Similarly, between the input shaft 1 and the counter shaft 4, there is a friction plate type counter shaft selection clutch 7 that connects and disconnects the power between the two shafts, and an idle gear 15 that reverses the rotation direction. equipped. Then, the human power shaft 1 and the counter shaft selection clutch 6
．． 7, there are gears 35, 36, .36, which transmit power from the human power shaft 1 to the counter shaft selection clutches 6, 7, respectively.
37 (Gear 15 is interposed between gears 36 and 37)
is interposed.

On the counter shaft 3, from the left in FIG.
A continuous (high speed) gear 9 is fixedly provided.

Similarly, on the counter shaft 4, from the left side in FIG.
and a second continuous (high speed) gear 11 are fixedly installed.

The output shaft 2, which is disposed parallel to the two counter shafts 3 and 4, has a gear 12 that is always in mesh with the gear 8 for the first forward train and the gear 10 for the first reverse train; A gear 13 that constantly meshes with the second gear 9 and the second reverse gear 11 is rotatably disposed with respect to the output shaft 2, respectively.

Furthermore, a gear selection clutch 14 is interposed between the gears 12 and 13 on the output shaft 2 to selectively connect the output shaft 2 and these gears 12 and 13. This gear selection clutch 14 is formally constructed of a dog clutch type with a synchronizing mechanism.

Incidentally, in the case of this embodiment, the output shaft 2 and the counter shafts 3 and 4 are arranged in a positional relationship as shown in FIG. 2(a) in a direction perpendicular to the axis.

However, as another embodiment, when the input shaft 1 and the output shaft 2 are arranged in parallel axes, they may be arranged in a positional relationship as shown in FIG. 2(b).

The countershaft selection clutch 6.7 is controlled by a piston-cylinder mechanism 6a, 7a (see FIG. 3) within the clutch 6.7, which is controlled by a manual switching valve, and the gear selection clutch 14 is It is configured to be operated by a hydraulic actuator 29 (see FIG. 3) controlled by a solenoid valve.

That is, the transmission having the configuration shown in FIG. 1 is configured to be operated by the hydraulic circuit shown in FIG. It is configured to be operated under the control of To explain the configuration of the hydraulic circuit shown in FIG. 3, pressure oil from the hydraulic pump 20 is supplied to the above-mentioned torque converter 5 via a conduit 22 equipped with a pressure regulating valve (pressure regulating valve) 21. , then oil cooler 23
．． It is configured to pass through the filter 24, lubricate each part of the device, and return to the reservoir tank 32.

Further, a branch circuit A branches from the pipe 22 and performs switching control of the counter shaft selection clutch 6.7 (in this embodiment, forward/reverse switching control), and a branch circuit A that performs switching control of the gear selection clutch 14. It is connected to a branch circuit B that performs switching control between the first speed and the second speed in this embodiment.

A branch circuit A that performs switching control of the counter shaft selection clutch, that is, forward/reverse switching control in this embodiment.
The side branches off from the conduit 22 and is connected to a switching valve 25 via a throttle valve 24 .

This switching valve 25 is configured to selectively supply pressure oil to the above-mentioned counter shaft selection clutch 67 using a three-position selection lever 30.

One port of the switching valve 25 is connected to the reservoir tank 32 side.

Further, it is further branched from between the throttle valve 24 and the switching valve 250 and connected to an inching valve 26 and a solenoid valve 27 called a hydraulic modulator, which are arranged in parallel. This solenoid valve 27 is connected to the electric circuit 4
0 is connected to the position sensor 33 of the lever 30, and in conjunction with the operation of the lever 30, it is configured to return (leak) a part of the pressure oil to the reservoir tank 32 side at the time of starting to soften the shock at the time of starting. has been done.

On the other hand, a branch circuit B, which performs switching control of the gear selection clutch 14 (see FIG. 1), that is, switching control between the first speed and the second speed in this embodiment, is branched from the pipe line 22 and includes a solenoid valve. 28, the gear selection clutch 1
Hydraulic actuator 2 that operates 4 (see Figure 1)
9 is connected. And the above solenoid valve 2
8 is configured to be automatically switched under control from a control device (not shown) in response to an operator's instruction, the degree of depression of an accelerator pedal (not shown), engine rotational speed, etc. Further, as shown in FIG. 3, the hydraulic actuator 29 is of a three-position type, and has two pistons 29c with different diameters in a stepped cylinder 29b.
, 29d are arranged, and the rod 2 is connected to one piston 29d.
9a to the neutral position shown in the figure, a second position obtained by moving the piston 29d to the right from that position, and a third position obtained by moving both the pistons 29c and 29d to the left from the neutral position. The configuration is such that the position of In the case of such a configuration, since the neutral position is obtained by hydraulic pressure from both sides, there is an advantage that the neutral position can be reliably obtained. In addition, the gear selection clutch 14
(See Figure 1), instead of the above hydraulic actuator,
It may be configured to operate using an electric motor, and in this case, it can be operated only with an electric signal, so
There is no need for hydraulic piping, etc., which simplifies the structure.

In addition, the gear selection clutch 14 (see Fig. 1 + tg
) are attached to the rod 29a of the hydraulic actuator 29 that operates switches 5w1-5w2 for confirming each position of their operation.

As described above, the solenoid valve 28 is controlled by a control device (not shown) or the like in a feedback manner using electrical signals from the switches Swl to Sw3.

Thus, the present transmission operates as follows.

Now, suppose that the lever 30 in Fig. 3 is moved forward (to the left in Fig. 3) and the vehicle is moving forward, and when the vehicle speed reaches zero or extremely low speed and has substantially stopped, the lever 30 in Fig. 3 is moved to the reverse side (left side in Fig. 3). 3), the control device immediately determines from the switches Sw and -zsw3 whether the solenoid valve 28 is connected to the first speed or the second speed of the counter shaft. If the gear is checked and the gear is in the second gear, the gear is returned to the first gear. This operation is instantaneously performed. At this time, the lever 30
By the tilting operation, the spool of the switching valve 25 moves from the left side to the right side in FIG. 3. Therefore, the pressure oil from the hydraulic pump 20 side was previously supplied to the counter shaft selection clutch 6 side, but now the hydraulic pump 20 side and the counter shaft selection clutch 7 side are connected, and the pressure oil is supplied to the counter shaft selection clutch 6 side. 6 is turned OFF (released), and the counter shaft selection clutch 7 is operated by the hydraulic circuit so as to be turned ON (connected). Therefore, this switching valve 2
5, the switching from one countershaft to the other countershaft is performed by forming a state in which the next gear to be connected is connected to the countershaft to be changed, The currently connected counter shaft is switched to the other counter shaft. Therefore, the gear change can be performed in a shorter time than in the conventional case where the clutch is turned off, the gear is changed, and the scratch is turned on. That is, extremely good response performance can be obtained.

At the time of this switching, the position sensor 3
3, the spool of the solenoid valve 27 moves left and right for a predetermined period of time in FIG.
This state is repeated to gradually increase the pressure of the pressure oil being supplied to the switching valve 25 side. Therefore, at the time of starting when the forward and reverse modes are switched, the impact of starting caused by instantaneous engagement of one of the counter shaft selection clutches is alleviated.

Further, as shown in the hydraulic circuit of FIG. 3, for the switching valve 25 that operates power transmission, a throttle valve 24 is provided on the hydraulic pump 20 side, and a branch is provided between the throttle valve 24 and the switching valve 25. By arranging the inching valve 26 whose output port side communicates with the reservoir tank 32 side, and the solenoid valve 27, as described above, it is possible to alleviate the shock at the time of starting when switching between forward and reverse travel, and By manually operating the inching valve 26, delicate operation control unique to industrial vehicles can be performed. That is, for example, transporting (loading) paper rolls using a forklift.
In this case, the core must be placed on the paper roll that is already in stock so that the core matches exactly, so the mm”-
Movement in cm units is required, but when performing such an operation, by manually operating the inching valve 26, the pressure oil supplied to the switching valve 25 is changed to the inching valve 26. By escaping from the valve 26 to the reservoir tank 32 side, extremely delicate operation control can be performed.

In this case as well, the pressure between the hydraulic pump 20 and other hydraulic equipment can be reduced to the extent that the pressure between the hydraulic pump 20 and other hydraulic equipment is reduced by the action of the throttle valve 24, as in the case of the shock mitigation operation by the solenoid valve 27 described above. There isn't.

Furthermore, from the first speed to the second speed in the forward or reverse state,
A control device (not shown) operates the solenoid valve 28 according to the degree of depression of the accelerator pedal, the engine speed, etc. For example, if the accelerator pedal is further depressed while the vehicle is running in first gear, the control device detects this change and moves the spool of the solenoid valve 28 to the right. This movement of the spool of the solenoid valve 28 to the right causes the rod 29a of the hydraulic actuator 29 to move from the left to the right, and this movement causes the switch Sw+ to turn OFF.
Confirmed by becoming N. And the above rod 2
By moving 9a, gear selection clutch 1 shown in FIG.
The sleeve 14a of No. 4 moves to the right, and the gear 9 or 11 on the countershaft is connected to the output shaft 2, thereby establishing the second speed in forward or reverse travel.

If the operational state of each component of the transmission device in such a desired speed change state is represented by "o", it will become as shown in the table of FIG. 9.

By the way, in the above embodiment, the case of a torque converter type automatic transmission device was explained, but the torque converter 5
(See Fig. 1) is replaced with a power transmission member 5° having a torsional damper function as shown in Fig. 4, and each counter shaft selection clutch By controlling the clutch and the clutch for selecting each gear with a control device, it is possible to easily provide fully mechanical automatic gear shifting.

Further, the embodiment of the first invention has good responsiveness when switching between forward and reverse, so it is effective for industrial vehicles used in applications where switching between forward and reverse is frequent; however, the transport distance is In the case of industrial vehicles used for long applications, as shown in FIG. 4 is provided with a second speed gear 9.11 for forward and reverse movement, and in this case, in the hydraulic circuit of FIG.
If a throttle valve 34 (indicated by a two-dot chain line) is interposed between 5 and the reservoir tank 32, and the changeover valve 25 is operated to switch between the first speed and the second speed, the first speed It is possible to provide a transmission device that can transmit power without interruption when switching between the first and second speeds. That is, if now, lever 3 in FIG.
0 to the 1st gear side (left side in Figure 3) and driving in 1st gear, if you operate the tilting operation to the 2nd gear side (right side in Figure 3), in Figure 3, the switching The spool of valve 25 moves from left to right. Therefore, the pressure oil from the hydraulic pump 20 side is transferred to the counter shaft selection clutch 6.
The hydraulic circuit on the counter shaft selection clutch G side passes through the instantaneous neutral position (the position where the hydraulic circuit on the counter shaft selection clutch 6 and 7 side communicates with the reservoir tank side). The internal pressure does not drop momentarily due to the action of the throttle valve 34, but maintains the pressure on the plate (at least the pressure that creates a half-clutch state) for a predetermined time, and within that predetermined time, the pressure on the hydraulic pump 20 side and the counter shaft are maintained. The selection clutch 7 side is communicated with the counter shaft selection clutch 7 to generate a hydraulic pressure sufficient to bring the counter shaft selection clutch 7 into a half-clutch state. Therefore, the switching from one countershaft to the other countershaft caused by switching the switching valve 25 is performed after both countershafts are connected to the human power shaft in a half-clutch state.

Therefore, a state where the power is interrupted when switching between the first speed and the second speed does not occur.

In addition, in the case of the transmission according to the present invention, all the gears are composed of external gears, so by removing the gears constituting the device according to the purpose or price, it is possible to change the transmission to two forward speeds and one reverse speed. Various transmission devices such as the above can be provided. For example, in FIG. 4, a transmission with two forward speeds and one reverse speed can be achieved by removing the gear 50, or by removing the gears 50, 51, 52 and gear selection clutch 53 and fixing the gear 54 to the output shaft 2. , it is possible to provide a transmission with one forward speed and one reverse speed, which is the same as the conventional one, and the power is not interrupted.

Also, when the input shaft l and the output shaft 2 are arranged in parallel axes (
2(b) and 6), the shaft length of the transmission can be further shortened by changing the hydraulic pump 20 from the position shown in FIG. 1 to the position shown in FIG. I can do it. The configuration of this device from the direction perpendicular to the axis is the second
As shown in Figure (b).

Incidentally, in each of the above embodiments, a gear train that meshes with a gear train fixedly installed on the counter shaft is disposed on the output shaft 2, and the counter shaft selection clutch 6.7 is connected to the counter shaft 3.
. That is, a counter shaft selection clutch 6.7 is interposed between the counter shaft 3.4 and the output shaft 2 to connect and disconnect between these shafts, and the gears 8 and 9 on the counter shafts 3 and 4 , 10.11 and the gear selection clutch 14 are connected to the input shaft I.
Even if it is disposed above, the same effect as in the above embodiment can be obtained. Moreover, in the case of such a configuration, the counter shaft 3.4 is shifted to a different speed as shown in FIG. Since it can be positioned above the device, the counter shaft selection clutches 6.7 disposed on the counter shafts 3.4 will not be immersed in the lubricating oil of the transmission. Loss of torque caused by immersion in water can be eliminated. That is, it is possible to provide a transmission with good mechanical efficiency. In the skeleton diagram of FIG. 7, the gears 35 and 38 are shown separated vertically, but these gears 35 and 38 are actually meshed as shown in FIG. 8. . Further, in FIGS. 7 and 8, the same shafts or gears as shown in FIGS. 1 and 2 are indicated using the same reference numerals.

Furthermore, the transmission device according to the present invention including each of the above-mentioned modified embodiments has a gear selection clutch disposed on the output shaft, and outputs the output from the gears fixedly installed on the two counter shafts via the gear selection clutch. Since power is transmitted to the gears rotatably disposed on the shaft, the number of gear selection clutches is minimized, simplifying the configuration, reducing the cost and reducing the volume of the device. It contributes to making it a combination.

(Effects of the Invention) Since the transmission according to the present invention is configured and operates as described above, it does not have low responsiveness or interruption of driving force during gear shifting, which lowers work efficiency, unlike conventional gear shifting devices. Therefore, work efficiency is greatly improved. Also,
Fuel efficiency is also improved because there is no wasted power due to poor responsiveness or power failure.

Moreover, since it can be stored within the same volume as a conventional transmission, it can be installed in a small vehicle.

In addition, by replacing or removing the gears, it can be used as a transmission for various purposes, so mass production can be expected, and since it can be supplied at low cost, it can be easily installed in small industrial vehicles.

Furthermore, it also becomes possible to perform delicate motion control, which is particularly required for industrial vehicles due to their use.

[Brief explanation of drawings]

FIG. 1 is a skeleton diagram showing the overall configuration of a torque converter type automatic transmission with two forward speeds and two reverse speeds according to the present invention, and FIG. 2(a) shows the arrangement structure in the direction perpendicular to the axis of FIG. 2(b) is a diagram showing the arrangement structure in the direction perpendicular to the axis when the human power shaft and the output shaft are arranged on parallel axes, and FIG. 3 is a circuit showing the hydraulic circuit for operating the transmission. Figure 4 is a skeleton diagram showing the configuration of the mechanical automatic transmission device 2, Figures 5, 6, and 7 are skeleton diagrams showing other embodiments, and Figure 8 is the gear shift shown in Figure 7. FIG. 9 is a diagram showing the arrangement structure of the device in the direction perpendicular to the axis, and is a table showing the operating state of each component of the transmission in a desired speed change state with Oj marks. ■...Input shaft; 2... Output shaft, 3, 4... Counter shaft, 6, 7... Counter shaft selection clutch, 8...
・Forward 1st speed gear, 9... Forward 2nd speed gear, IO
... 1st speed gear for reverse movement, 11 ... 2nd speed gear for reverse movement, 14 ... gear selection clutch, 24 ... throttle valve,
25...Switching valve, 26...Inching valve, 27
... Solenoid valve, 34... Throttle valve. ] 5 Fig. 1 (a) (b) Fig. 2 Fig. 3 Fig. 3 52 Fig. 4 Fig. 8 ] 0 Fig. 9

Claims (3)

[Claims] (1), two counter shafts are arranged parallel to the input shaft, and an output shaft is arranged parallel to these two counter shafts, and between the above two counter shafts and the input shaft or between the above two counter shafts. A counter shaft selection clutch is interposed between the output shaft and the output shaft, and a gear train for forward movement is disposed on one of the counter shafts, and a gear train for forward movement is disposed on one of the counter shafts. a gear train for reverse movement is arranged on the output shaft or the input shaft, and a gear train that meshes with each gear on each of the counter shafts is selected from among the gears constituting the gear train. It is disposed so that it can be freely engaged and disengaged via a gear selection clutch so that it can mesh with any gear of the gear train on the counter shaft, and when switching between forward and reverse, the counter on the uncoupled side The next gear to be selected on the shaft is connected to that countershaft via a gear selection clutch, and when this connection is completed, the countershaft selection clutch of the currently connected countershaft is turned OFF, A transmission for an industrial vehicle, comprising a control means for switching and controlling a counter shaft selection clutch of the counter shaft for which the gear connection has been completed to turn on the counter shaft selection clutch. (2), two counter shafts are arranged parallel to the input shaft, and an output shaft is arranged parallel to these two counter shafts, and between the above two counter shafts and the input shaft or between the above two counter shafts. A countershaft selection clutch is interposed between the output shaft and the output shaft, and a clutch for selecting a countershaft is interposed between these shafts to form a half-clutch state. At the same time, second gear trains for forward and reverse gears are arranged on the other one of the counter shafts, and the output shaft or the input shaft meshes with each gear on each of the counter shafts. A gear train is connected and disengaged via a gear selection clutch so that any one of the gears constituting the gear train can be selectively engaged with any gear of the gear train on the counter shaft. It is freely arranged, and when switching between forward and reverse 1st and 2nd speeds,
An industry characterized by comprising a control means for controlling the above-mentioned two counter shaft selection clutches to be switched through a half-clutch state, and then switching from one clutch to the other clutch. Vehicle transmission. (3), two counter shafts are arranged parallel to the input shaft, and an output shaft is arranged parallel to these two counter shafts, and between the above two counter shafts and the input shaft or between the above two counter shafts. A counter shaft selection clutch is interposed between the output shaft and the output shaft to connect and connect these shafts, and a gear train is provided on each of the counter shafts to selectively engage gears on the output shaft or the input shaft. are disposed so as to be freely connected and disengaged, and the counter shaft selection clutch provided on each of the above counter shafts is selectively operated as appropriate to transmit power from the input shaft to the output shaft via the selected counter shaft. A transmission for an industrial vehicle configured to transmit data, wherein the two counter shaft selection clutches are configured to be operated by a hydraulic circuit having a hydraulic circuit as described below. . (a), so that the output side port is connected to the operating hydraulic circuit of the two counter shaft selection clutches, and the input side port is connected to the hydraulic pump side via the throttle valve.
A position type switching valve is provided, (b) branching from between the throttle valve and the switching valve,
A manual relief valve and a solenoid valve which is operated to repeat ON-OFF operation by a signal from the control device when the switching valve is switched, and whose output side communicates with the reservoir tank side are provided.