JPH0784182B2 - Controller for spin turn in combine etc. - Google Patents

Description

The present invention relates to a spin turn control device in a combine or the like.

(Prior Art) In the publicly known Japanese Utility Model Laid-Open No. 58-48567, a left clutch body and a right clutch body which are removably engaged with a center gear rotated by a hydraulic continuously variable transmission are disclosed. It has a mechanism for connecting and disconnecting to and from the center gear and a hydraulic reverse mechanism having a hydraulic clutch body that can rotate the left axle and the right axle in opposite directions, and after the left clutch body or the right clutch body is disengaged from the center gear. There is disclosed a spin-turn control device in a combine or the like configured such that the hydraulic clutch body of the hydraulic reverse mechanism is "contacted".

Although not known, Japanese Patent Application No. 63-149101 by the same applicant
In the specification, a left clutch body and a right clutch body that mesh with a center gear that rotates by a hydraulic continuously variable transmission, and hydraulic left and right cylinders that mesh with the center gear. And a hydraulic reversing mechanism having a reverse power connecting / disengaging clutch body capable of rotating the left axle and the right axle in opposite directions, and the hydraulic reversing mechanism after the left clutch body or the right clutch body is disengaged from the center gear. In a control device for a spin turn in a combine or the like configured so as to be “contact”, a left clutch disengagement detection switch and a right switch which are turned on when the left and right clutch bodies are disengaged from the center gear, in the vicinity of the left and right clutch bodies. A clutch disengagement detection switch is installed to operate the spin turn valve for opening and closing the oil supply path of the hydraulic reverse mechanism. Turn solenoid, the spin-turn control device in the configuration were combined such as current through the left clutch disengaging detecting switch or the right clutch disengaging detecting switch is described.

(Problems to be Solved by the Invention) In the former known technology, the technology regarding the detailed configuration is not clear.

In the latter prior art, one of the left clutch body and the right clutch body is in the "contact" state and the other clutch body is in the "off" state to perform a spin turn. The configuration electrically detects that the left and right clutch bodies are disengaged from the center gear, and the reverse rotation power relay clutch body "contacts".
I am trying to become. However, if the foot pedal of the free side clutch body (also used as a brake) is mistakenly pressed during the spin turn, the rotation is transmitted from the reverse power relay clutch to the controlled clutch body via the other clutch body. , Mechanical lock may cause malfunction.

Therefore, the present invention electrically detects the connection / disconnection between the left and right clutch bodies and the center gear to open / close the oil feed path of the hydraulic clutch body, so that the foot pedal of the clutch body on the free side is erroneously operated during the spin turn. Even if you step on it, the mechanical lock will not be activated.

(Means for Solving the Problems) Accordingly, the present invention is directed to the spin lever 68 and the left and right clutch bodies 2
Left and right axles 43, 44 that rotate through 0, 21 and the left and right axles 4
A hydraulic reverse rotation mechanism 56 provided between Nos. 3 and 44, and left and right foot pedals 91 and 94 for moving and braking the left and right clutch bodies 20 and 21 are provided. When the spin lever 68 is operated, the left and right clutch bodies are provided. One of 20 and 21 is "contact", the other is "off" and the hydraulic reversing mechanism 56 is "contact", and the left and right axles 43 and 44 are opposite to each other via the hydraulic reversing mechanism 56. In the rotating type, switches 96 and 97 for detecting the operation of the left and right foot pedals 91 and 94 are provided at positions near the operating portions of the left and right foot pedals 91 and 94, and during the spin turn by the spin lever 68, When the switches 96 and 97 detect the operation of the foot pedal of the foot pedals 91 and 94 that moves the other clutch body that is "off", the hydraulic reversing mechanism 56 automatically turns off. Combines configured to For spin turn control device in, and the left and right clutch body 2
Left and right switch arms 100 and 101 are provided in the vicinity of 0 and 21, and the left and right switch arms 100 and 101 are pressed and turned on when the left and right clutch bodies 20 and 21 are turned off. 69 and 70 are provided, and the left and right switch arms 100 and 101 are retracted from the pressing action of the left and right clutch bodies 20 and 21 against the elasticity of the springs 104 and 105 when the left and right foot pedals 91 and 94 are stepped on. Spin turn solenoid for activating the oil supply path opening / closing spin turn valve 66 of the hydraulic reversing mechanism 56.
Reference numeral 73 denotes a spin turn control device in a combine or the like configured to be energized via the left clutch disengagement detection switch 69 or the right clutch disengagement detection switch 70.

(Embodiment) An embodiment of the present invention will be described with reference to the drawings. 1 is a mission case such as a combine, in which an input shaft 2 is laterally provided at an upper position, and one end of the input shaft 2 is a hydraulic continuously variable transmission ( A hydrostatic transmission 3 is attached, and an output pulley 4 reaching the cutting portion is attached to the other end of the input shaft 2.

A switching gear group 8 including a large gear 5, a middle gear 6, and a small gear 7 is slidably fitted in the input shaft 2 in the axial direction, and a shifter 9 is engaged with the switching gear group 8. Reference numeral 10 is a shifter shaft on which the shifter 9 is mounted.

Reference numeral 11 denotes an intermediate shaft, and a small gear 12 meshing with the large gear 5, a middle gear 13 meshing with the middle gear 6, and a large gear 14 meshing with the small gear 7 are fixed to the intermediate shaft 11, respectively. . A fixed gear 16 that engages with the center gear 15 is fixed between the middle gear 13 and the large gear 14.

Reference numeral 17 denotes a side clutch shaft, and the center gear 15 is loosely fitted in the center position of the side clutch shaft 17 only for rotation.

Left inner teeth 18 and right inner teeth 19 are formed on both sides of the center gear 15, respectively. The side clutch shaft 17 is provided with a left clutch body 20 that is connectable / detachable with respect to the left inner tooth 18 and a right clutch body 21 that is releasable with respect to the right inner tooth 19 so that they can slide only. Reference numerals 20a and 21a are tooth portions that mesh with the left and right inner teeth 18 and 19, and the tooth portions 20a and 21a are formed to have a width that protrudes outward even if they mesh with the left and right inner teeth 18 and 19.

22 is a shifter groove formed in the left clutch body 20, 23 is a shifter groove formed in the right clutch body 21,
A left shifter 24 is engaged with 22 and a right shifter 25 is engaged with the shifter groove 23.

A left brake 26 and a right brake 27 are provided outside the left and right clutch bodies 20 and 21, respectively. Left and right brakes 26, 27
Is formed of a left disc 28 and a right disc 29 (FIG. 2) fixed to the mission case 1, a left disc 32 and a right disc 33 fixed to the left annular drum 30 and the right annular drum 31, respectively.

Left and right inner teeth 34 and 35 are integrally formed on the left and right annular drums 30 and 31, respectively, and the left and right inner teeth 34 and 35 are provided outside the left and right tooth portions 20a and 21a of the left and right clutch bodies 20 and 21, respectively. The left outer tooth 36 and the right outer tooth 37 formed on the above are meshed with each other.

A base of an arm 90 is attached to the base of the left shifter 24, and a rod 92 connected to a left foot pedal 91 is attached to the arm 90.
The base of the right shifter 25 is connected to the base of the arm 93, and the arm 93 is connected to the rod 95 connected to the right foot pedal 94.

The left and right clutch bodies 20 and 21 include left and right foot pedals 91 and 94.
When stepping on, the left and right shifters 24, 25 move in the axial direction, the engagement with the left and right inner teeth 18, 19 is released, and the left and right annular drums 30, 31
And the left and right annular drums 30 and 31 are pressed, the left and right disks 32 and 33 are brought into pressure contact with the left and right disks 28 and 29, and the left and right brakes are operated.

A left reduction gear 38 and a right reduction gear 39 mesh with the left tooth portion 20a and the right tooth portion 21a of the left and right clutch bodies 20, 21, respectively. 40
Is a reduction shaft of the left reduction gear 38 and the right reduction gear 39.

The left small reduction gear 41 is fixed to the outside of the left reduction gear 38, and the right small reduction gear 42 is fixed to the outside of the right reduction gear 39.

A left axle 43 and a right axle 44 are mounted near the reduction shaft 40. A left drive gear 45 meshing with the left small reduction gear 41 is fixed to the left axle 43, and a right drive gear 46 meshing with the right small reduction gear 42 is fixed to the right axle 44.

A clutch shaft 47 is mounted near the left and right axles 43, 44,
The clutch shaft 47 is provided with a reverse power relay clutch 48 for spin turns. The reverse rotation power relay clutch body 48 is formed of one side 49 fixed to the clutch shaft 47 and the other side 50 loosely fitted to the clutch shaft 47, and when hydraulic pressure acts, the one side 49 and the other side. 50 is connected and rotates integrally.

A gear 51 is integrally formed on the other side 50, and the gear 51 is meshed with the right drive gear 46.

An intermediate gear 52 is fixed to the right side of the clutch shaft 47. A counter shaft 53 is provided near the clutch shaft 47, and a left intermediate gear that meshes with the left drive gear 45 is provided on the left side of the counter shaft 53.
54, and a right intermediate gear 55 that meshes with the intermediate gear 52 is fixed to the right side of the counter shaft 53.

The transmission mechanism from the gear 51 meshed with the right drive gear 46 to the left intermediate gear 54 meshed with the left drive gear 45 through the reverse rotation power relay clutch body 48 is a hydraulic reverse mechanism 56 for spin turn. Becomes

3 shows a hydraulic circuit for controlling the left and right clutch bodies 20 and 21 and the reverse power relay clutch 48, in which 57 is an oil tank, 58 is a hydraulic pump, and 59 is a relief valve. 60 is a side clutch valve, 61 is an unload valve, 62 is a left cylinder, 63 is a right cylinder, 64 is a steering relief valve, 65 is a steering lever, 66 is a spin turn valve,
67 is a spin turn relief valve, 68 is a spin turn lever, 69 is the left clutch body 20 is the center gear 15 left internal teeth 18
The left clutch disengagement detection switch, which is turned on when the arm 90 comes into contact with the arm, when the right clutch disengagement switch 70 is turned on when the right clutch body 21 disengages from the right internal tooth 19 of the center gear 15. A detection switch, 71 is a left side clutch solenoid that moves the side clutch valve 60 to the right, 72 is a right side clutch solenoid that moves the side clutch valve 60 to the left, 73 is a spin turn solenoid that moves the spin turn valve 66 to the left, and 74 is an Load valve
An unload solenoid that moves 61 to the left.

The left and right cylinders 62 and 63 are double-acting cylinders.The main chamber 75 of the left cylinder 62 and the side clutch valve 60 are connected by an oil feed duct 76, and the main chamber 77 of the right cylinder 63 and the side clutch valve 60 are fed. Connected by oil duct 78, each sub-chamber 7
An oil return duct 81 is connected to 9 and 80.

Openings 82 and 83 are separately formed in the main chambers 75 and 77, and the openings 82 and 83 are connected to the spin turn valve 66 through an oil discharge duct 84. The openings 82 and 83 are normally closed from the inside by pistons 85 and 86, but the main chambers 75 and 77
When the pistons 85, 86 are moved up to a position where the left and right clutch bodies 20, 21 are disengaged from the left and right inner teeth 18, 19, the openings 82, 83 are formed so as to open.

The steering lever 65 and the spin turn lever 68 are levers that can be switched to the right, neutral, and left "3 positions".

FIG. 4 is an electric circuit diagram, and 96 is the left foot pedal 91.
The left brake detection switch that turns off when you press, 97 the right brake detection switch that turns off when you step on the right foot pedal 94, 87 the switch that turns on when the auxiliary gear shift lever reaches medium speed, and 88 the main gear shift lever. A switch that is turned on when the vehicle speed is 0.4 to 0.5 m / s or less, 89 is a delay circuit, and the left side clutch solenoid 71 or the right side clutch solenoid is energized by operating the spin turn lever 68.
At 72, after the spin turn lever 68 returns to the neutral position, it is further energized for about 1.2 seconds.

FIGS. 5 to 7 show a second embodiment, in which the switch pressing arm 98 is provided on the left shifter 24 and the right shifter 25.
The switch pressing arms 99 are attached respectively to the left clutch disengagement detection switch 69 and the right clutch disengagement detection switch 70 are attached to the left and right switch arms 100 and 101, respectively. The switch arms 100 and 101 have shafts 102 and 103 at their bases.
Further, it is axially mounted so as to always return to the neutral position via the springs 104 and 105. Pins are attached to the rotating ends of the switch arms 100 and 101.
Install 106 and 107. When the left foot pedal 91 or the right foot pedal 94 is depressed, the pins 106 and 107 come into contact with the arm 90 or the arm 93, and the left clutch disengagement detection switch.
69 or the right clutch disengagement detection switch 70 is retracted from the left switch pressing arm 98 or the right switch pressing arm 99, the left clutch disengagement detection switch 69 or the right clutch disengagement detection switch 70 is turned off, and the spin turn is stopped.

(Operation) Next, the operation will be described.

The present invention is configured as described above, and in normal traveling, the rotation of the hydraulic continuously variable transmission 3 is transmitted through the switching gear group 8 to the small gear 1
2, transmitted to any of the middle gear 13 and the large gear 14 to rotate the intermediate shaft 11, and transmitted to the center gear 15 via the fixed gear 16 fixed to the intermediate shaft 11.

The left and right inner teeth 18, 19 of the center gear 15 have a left and right clutch body 2
Since 0 and 21 mesh, the left and right reduction gears 38 and 39 rotate via the left and right clutch bodies 20 and 21, and the left and right reduction gears 38 and 39
The left and right small reduction gears 41, 42 fixed to the right and left rotate, the left and right driving gears 45, 46 which are always meshed with the left and right small reduction gears 41, 42 rotate, and the left and right axles 43, 44 rotate to travel.

In the above, since the reverse power motive power disengagement clutch body 48 is not hydraulically applied, the one side 49 and the other side 50 are idling.

Then, in this state, spin turn the aircraft (left axle 43
And the right axle 44 are rotated in the opposite direction and turned on the spot), the spin turn lever 68 may be switched to the left or right. That is, for example, when the spin turn lever 68 is tilted to the right to turn right (upper side in FIG. 4), the right side clutch solenoid 72 is energized (switches 87 and 88 are ON), and the side clutch is turned on. The valve 60 is switched to the right (moved to the left in the drawing), and the delay circuit 89 detects that the spin turn lever 68 is tilted to the right.

When the side clutch valve 60 is switched, oil is sent to the main chamber 77 of the right cylinder 63, and the shaft of the piston 86 extends. Then, the right clutch body 21 moves to the right side via the right shifter 25 (Fig. 1), the engagement between the right clutch body 21 and the right inner tooth 19 is released, and the arm 93 causes the right clutch disengagement detection switch 70 to operate. Press.

When the right clutch disengagement detection switch 70 is turned ON, the spin turn solenoid 73 is energized, the spin turn valve 66 is switched to the right side (left in the drawing), and the opening 83 opens so that the hydraulic pressure from the hydraulic pump 58 Is transmitted to the reverse power relay clutch 48.

When hydraulic pressure is applied to the reverse rotation power relay clutch 48, one side 49 and the other side 50 of the reverse power relay clutch 48 come into pressure contact with each other, and in this state, the rotation of the left drive gear 45 passes through the left intermediate gear 54. The right intermediate gear 55 fixed to the counter shaft 53 is rotated, and the intermediate gear 52 meshing with the right intermediate gear 55 is rotated to rotate the clutch shaft.
Rotate 47 to rotate clutch shaft 47 from one side 49 to the other 50.
And the gear 51 is rotated. Gear 51 is right drive gear 46
The right drive gear 46 rotates to engage the right axle 44
Is rotated in the opposite direction to the left axle 43. Therefore, the aircraft spin-turns.

As described above, when the aircraft spin-turns, the right drive gear 46 rotates in the opposite direction to the normal traveling, but the reverse power relay clutch body 48 that transmits the reverse rotation to the right drive gear 46, The right clutch 21 is disengaged from the right internal tooth 19 and electrically controlled so that it operates after turning on the right clutch disengagement detection switch 70.Therefore, the normal rotation force for normal running and the reversal for spin turn are used. The force and the right drive gear 46 do not act simultaneously.

If the right foot pedal 94 is accidentally depressed during the spin turn in which the right clutch body 21 is disengaged from the right internal tooth 19, the right brake 27 is actuated via the arm 93 and the right shifter 25 to lock the right clutch pedal 21. However, in the present invention, the right brake detection switch 9 is turned off when the right foot pedal 94 is depressed.
7 is provided, and the switch 97 is normally connected to a circuit, but when it is turned off, the circuit is disconnected to open and close the oil feeding path of the rolling power relay clutch 48.
It acts on the spin-turn solenoid 73 of 66 to stop the oil supply to the rolling power relay clutch 48. Therefore, the spin turn is stopped and the mechanical lock is prevented.

In the second embodiment, the switch shift arm 98 is attached to the left shifter 24.
The switch pressing arms 99 are attached to the right shifter 25 respectively, and the left clutch disengagement detection switch 69 and the right clutch disengagement detection switch 70 are respectively left and right switch arms.
The switch arms 100 and 101 are attached to the shafts 102 and 103 via springs 104 and 105 so that the bases of the switch arms 100 and 101 are always returned to the neutral position. Is the left foot pedal 91 or the right foot pedal
When stepping on 94, the pin 90 with which arm 90 or arm 93 abuts
Since 6 and 107 are attached, the left foot pedal 91
Or, when the right foot pedal 94 is stepped on, the arm 90 or the arm 93 abuts the pin 106 or the pin 107, and the switch arms 100 and 101 are rotated about the shafts 102 and 103. Clutch disengagement detection switch
70 is retracted from the left switch pressing arm switch 98 or the right switch pressing arm switch 99, and the left clutch disengagement detection switch 69 or the right clutch disengagement detection switch 70 is set.
Turn off and reverse power relay clutch body 4 of hydraulic reverse mechanism 56
Turn off 8 to stop the spin turn.

(Effects) As described above, according to the present invention, the spin lever 68, the left and right axles 43 and 44 that rotate via the left and right clutch bodies 20 and 21, and the hydraulic reverse mechanism 56 provided between the left and right axles 43 and 44. And left and right foot pedals 91 and 94 for moving and braking the left and right clutch bodies 20 and 21, and when the spin lever 68 is operated, one of the left and right clutch bodies 20 and 21 is “contacted”, If the other one is "OFF" and the hydraulic reversing mechanism 56 is "contact", and the left and right axles 43, 44 rotate in opposite directions via the hydraulic reversing mechanism 56, the left and right foot pedals 91, 94 Switches 96, 97 for detecting the operation of the left and right foot pedals 91, 94 in the vicinity of the operating portion of
Is provided, during the spin turn by the spin lever 68,
When the switches 96, 97 detect the operation of the foot pedal of the foot pedals 91, 94 for moving the other clutch body which is "off", the hydraulic reversing mechanism 56 automatically "off". And a left and right switch arms 100 and 101 in the vicinity of the left and right clutch bodies 20 and 21. The left and right switch arms 100 and 101 are provided with the left and right clutches. Left and right clutch disengagement detection switches 69 and 70 are provided that are turned on when the bodies 20 and 21 are turned off.The left and right switch arms 100 and 101 are provided with springs 104, when the left and right foot pedals 91 and 94 are stepped on. A spin rotor configured to be displaced in the direction of retreating from the pressing action of the left and right clutch bodies 20 and 21 against the elasticity of 105 and actuating the spin turn valve 66 for opening and closing the oil feeding path of the hydraulic reverse mechanism 56. Down solenoid
Since 73 is a spin turn control device in a combine or the like configured to be energized via the left clutch disengagement detection switch 69 or the right clutch disengagement detection switch 70, the free side Even if the left foot pedal 91 or the right foot pedal 94 of the clutch body is depressed to brake, the mechanism is not locked for the above reason.

[Brief description of drawings]

FIG. 1 is a development view of a mission case, FIG. 2 is an enlarged view of essential parts, FIG. 3 is a hydraulic circuit diagram, FIG. 4 is an electric circuit diagram, and FIG. 5 is an enlarged view of essential parts of the second embodiment. 6 is a side view of the same, and FIG. 7 is an electric circuit diagram of the same. Explanation of symbols 1 ... mission case, 2 ... input shaft, 3 ... hydraulic continuously variable transmission, 4 ... output pulley, 5 ... large gear, 6 ...
… Middle gear, 7 …… small gear, 8 …… switching gear group, 9 …… shifter, 10 …… shifter shaft, 11 …… intermediate shaft, 12 …… small gear, 13 …… middle gear, 14 …… large Gears, 15 …… Center gear, 16 …… Fixed gear, 17 …… Side clutch shaft, 18 ……
Left internal tooth, 19 …… Right internal tooth, 20 …… Left clutch body, 20a ……
Tooth, 21 …… Right clutch body, 21a …… Tooth, 22 …… Shifter groove, 23 …… Shifter groove, 24 …… Left shifter, 25 ……
Right shifter, 26 …… Left brake, 27 …… Right brake, 28
…… Disc, 29 …… Disc, 30 …… Ring drum, 31
...... Ring drum, 32 …… Disc, 33 …… Disc, 34
…… Internal teeth, 35 …… Internal teeth, 36 …… External teeth, 37 …… External teeth, 38…
… Left reduction gear, 39 …… Right reduction gear, 40 …… Reduction shaft, 41…
… Left small reduction gear, 42 …… Right small reduction gear, 43 …… Left axle,
44 …… Right axle, 45 …… Left drive gear, 46 …… Right drive gear,
47 …… Clutch shaft, 48 …… Reverse rotation power relay clutch unit, 49
…… One side, 50 …… Other side, 51 …… Gear, 52 …… Intermediate gear,
53 …… Counter shaft, 54 …… Left intermediate gear, 55 …… Right intermediate gear, 56 …… Hydraulic reverse mechanism, 57 …… Oil tank, 58 ……
Hydraulic pump, 59 …… Relief valve, 60 …… Side clutch valve, 61 …… Unload valve, 62 …… Left cylinder, 63 …… Right cylinder, 64 …… Steering relief valve, 65
...... Steering lever, 66 …… Spin turn valve, 67 …… Spin turn relief valve, 68 …… Spin turn lever, 69 …… Left clutch disengagement detection switch, 70 …… Right clutch disengagement detection switch, 71 …… Left side Clutch solenoid, 72 …… Right side clutch solenoid, 73 …… Spin turn solenoid, 74 …… Unload solenoid, 75
…… Main room, 76 …… Oil supply duct, 77 …… Main room, 78 …… Oil supply duct, 79,80 …… Sub chamber, 81 …… Oil return duct, 82,83
...... Aperture, 84 ...... Oil discharge duct, 85,86 ...... Piston, 87,88 ...... Switch, 89 ...... Delay circuit, 90 ......
Arm, 91 …… Left foot pedal, 92 …… Rod, 93 ……
Arm, 94 …… Right foot pedal, 95 …… Rod, 96 ……
Left brake detection switch, 97 …… Right brake detection switch, 98 …… Switch pressing arm, 99 …… Switch pressing arm, 100, 101 …… Switch arm, 102,103 …… Axis,
104, 105 …… Spring, 106,107 …… Pin.

Claims (2)

[Claims] 1. A spin lever 68 and left and right clutch bodies 20, 21.
Left and right axles 43, 44 that rotate through
The hydraulic reversing mechanism 56 provided between the left and right clutch bodies 2
Left and right foot pedals to move and brake 0, 21 9
When the spin lever 68 is operated, one of the left and right clutch bodies 20 and 21 is “contact”, the other is “off” and the hydraulic reverse mechanism 56 is “contact”. The left and right axles 43, 44 rotate in opposite directions via the hydraulic reversing mechanism 56, and the left and right foot pedals 91, 94 are located in the vicinity of the operating portion.
Switches 96 and 97 for detecting the operations of 91 and 94 are provided, and the switch 9 is operated during the spin turn by the spin lever 68.
When 6 and 97 detect the operation of the foot pedal that moves the other clutch body of the foot pedals 91 and 94 that is "off", the hydraulic reversing mechanism 56 is automatically turned off. A control device for a spin turn in a combine or the like configured as described above. 2. The left and right switch arms 10 according to claim 1, which are located near the left and right clutch bodies 20 and 21.
0 and 101 are provided, and the left and right switch arms 100 and 101 are pressed and turned on when the left and right clutch bodies 20 and 21 are turned off.
The left and right clutch disengagement detection switches 69 and 70 are provided, and the left and right switch arms 100 and 101 are the left and right foot pedals.
When 91 and 94 are stepped on, the oil reversing path of the hydraulic reversing mechanism 56 is configured so as to be displaced in the direction of withdrawing from the pressing action of the left and right clutch bodies 20 and 21 against the elasticity of the springs 104 and 105. The spin turn solenoid 73 for operating the open / close spin turn valve 66 is a spin turn control device in a combine or the like configured to be energized via the left clutch disengagement detection switch 69 or the right clutch disengagement detection switch 70.