SU1625723A1 - Automatic speed and load control system of self-propelled vehicle - Google Patents

Abstract

The invention relates to vehicle technology, namely, to automatic transmission control devices of a vehicle. The purpose of the invention is to increase reliability by improving the quality of transients during automatic gear shifting. The switching on switch of the stabilization unit is designed to be connected. The invention relates to vehicle technology, in particular, to automatic control systems for speed and load modes of a self-propelled machine. The aim of the invention is to increase reliability by improving the quality of transients during automatic gear changes. Figure 1 is a schematic diagram of the system; figure 2 - characteristics of the system in the mode of stabilization speed. The system contains an information-measuring unit 1, an executive device that turns off the stabilization mode of one of the cavities of the hydraulic cylinder for pre-alignment of speeds to the power source and the hydraulic accumulator, and the opposite cavity to the drain by means of control amplifiers. In this case, both cavities of the speed stabilization cylinder are locked, and when the stabilization mode is on, both cavities of the cylinder cylinder are pre-aligned for grayness, while one of the cavities of the speed stabilization cylinder is connected to the hydraulic cylinder and opposite to the amplifier drain. In addition, the hydroac / ul tor is made with the possibility of permanent connection with pressure pini by means of amplifiers in their off position and by means of the on valve when the speed stabilization mode is off with pressure lee In the switched on position of the power saver or when the stabilization mode is off Hydroccumulator from source and | OI power switch (.I. 1 hp, 2 and,. gear change (Fig. 1), consisting of electro-hydraulic valves 2 3 whose electromagnets rely on information signals about high and low gears, developed by the information-measuring unit 1, control channels 4-7, amplifiers 8 and 9 of the control signals of the higher and lower gears, control valves 10 and 11 of the higher and lower gears, actuating hydraulic cylinders 12 and 13 of the higher and lower transmissions and time relays 14. Channel 4 controls are connected through control valve 11, through channel 6 and through the SJ SL VI hO CO

Description

Speech amplifier 9 cm of control with end-cavity control amplifier 8 of control signal by means of hydroline 15 1 control channel 5 is connected through control valve 10, through channel 7 h through control amplifier 8 of control signal cavity of hydrotilium control signal 9 by means of hydro-line 16 In turn, the control signal amplifier connects the Executive Hydrocyl Radr 1 ° to the pressure line 17 through the channel (hydroline) and went to the drain 19 (the amplifier 9 of the control signal cnflvi-ry executor nopopna g 1 | ngtgpl n 17 gamal 20} ibot with a drain 21 strengthened by 8 and cut ianon uppaplars n i in a single position, goin their cavities control-wi i srsrc gtpm ana / ju 22 and 23 c i a h o The main line 17 through the choke 21 of the Tortse va control valve turn-off time from the first position of the control caps 10 and 11 (as shown in FIG. 1) is connected to the pressure line –b via the channel 26 and in the second position of one of the control valves 10 and 11, it is connected to the tower 0 27 or 23 In the position of the repuser 14 times, the i -nest emptiness of the ijii 8 and the signal g ravlonr-l them (.- oi, i hotTL soyuzht with about 99 years before DS1Rom tKjce i hydrolines 30 and 3

The thorium cavity (protruding spring) of the control valve 10 has the ability to connect with the drain 3 from the hydraulic line 18 through the can 33 and the actuating hydraulic cylinder 12 12 as a response t the end of the nonoi control valve 11 has the ability to connect with the hydraulic valve 3- Hydrolines C through channel C5 and the executive 1-cylinder 13 Vp of the second position to entrolon valves can be removed by signatures, accompanying it with pressure, (IL 25 nepej throttles 36 and 3 / besides in the second position con i roln valve 10 t rtsova cavity 9 usmlitel control signal has the ability Cpd. with outlet 38 via the hose 39 parts in the second position of the control valve 11 toriova cavity usiln llch 8 uprshlenil signal has the ability to combine with plum gidsoliniyu 40 through 41

Pd.i, c 4 times, has the ability to connect the electro-hydraulic units 2 and 3 to the pressure line 42 through the channel 43 in the position in which it is fully ignited, and in the position we have a gyostouchch 1 relay or partially

it is born, electro-hydraulic valves of the CTC are unified from the source of the pitches, and the thread / first control signal is processed by the actuator in the form of

in the rotation of the shaft mechanism 44 of the rotatable actuator hydrojig | indra 12 and 13 and the gearbox associated with the shaft of the control gear that controls the coupling clutches

Speed stabilization unit contains

the speed sensor of the machine is made as an idronpump 45 v yrouiero a definite inmatic connection with the tire, I am looking at the morning of the morning

5 i of the form of a rsg leased rp with a r 4 uprar reni re ulprch we h vszangnggo system of tpg levers with a handle t-y and 48

p dn / bold Iuko ITKH 48 with psog / ryu, full-time paon tux sing / en ci lar 5 5 shi-ko-kopan 52 B1 luisnn analog-discretion porcion of 53 cocio itions from o | Otnik 54 and

Fuzhins 5b Bands (Ü6 rights / 1s of the companion i is not with 57 schoolinii, cho i nuei R olom ayug - Discrete, etc., with the bottom line of the drrsos and} g / eem diossel 46 3., 58 pi

gani RflOia hii ..- gfogti popvod1p rr & och under pressure from hydraulic synga y, 1, from the gearbox valve -7 turn on MOxiPi soooipt with hydrol nig 19 ankle-D kretnogo -,; bga ioatel 53 Aux yang1 yyyy nci to the other ripeo6 azovatep gidropichi51 and 6U i / r 1 are connected to face gk, with f-i fits i distributor control M -, co

be ibOHHo 1, the spread / n of the PSL 61 space and the bulkhead of the box body is possible to connect th & tTtH u2 r 63 upravl and g ihodor fb generator bb impuls i3 ivn67iio per

it is connected to the inlet distributor, 64 distributions are distributed1,174 by hydraulics 08 and 69 are connected to the cavities of the executive hydraulic cylinder 70 built in by the accelerator control circuit

Generatorbimplispod rm It doukhpozitsionnoe relay, 1, the state of the “ash gland 77 / springs 73 ak” mind // torus relay 75 Ер meni nopoiH. - otr1 h ustnn1 ol8ny cm Ct c and BG and iodeysuyut. rss about gem o

and, and springs 76

The input 05 of the pulse generator is connected by; wu of the position relay 71 og ovremg nns with relo 75 Rimeni hydrrini and 77 and with ak / mu l 7 h g, 1 control 11 / fi and

Time relay 75 is configured to connect, at the end of the filling phase of its working cavity, the end cavity 80 of the two-position relay 71 by means of the hydroline 81. The two-position relay 71 in the extreme upper position of the spool 72 has the ability to connect the battery 74 to the output 67 of the pulse generator 66, and a time relay 75 is provided with a drain 82. To keep the spool 72 in the extreme upper position, the input 65 of the pulse generator is configured to be connected via the throttle 83 to the end cavity 80.

The valve 52 for switching on the stabilization unit is configured to communicate the supply line 58 when the stabilization block is turned off via the hydraulic line 84 to the control cylinder of the actuating hydraulic cylinder 70. the piston of the latter is in the extreme left position corresponding to the minimum speed mode of the engine hydrolysed 85 is connected to drain 86. The pulse generator is then disconnected from the main supply 58 of the unit by the switch-on valve 52. Hydrolines 87 and 88 allow you to communicate the cavities of the actuator of the hydraulic cylinder 70 through the distributor 04 and the two-position relay 71 with a drain 89

The pre-alignment device, speeds, contains an executive speed cylinder 90, which is installed in the accelerator control drive, the piston of which is spring-loaded at both ends and the accumulator 91, which serves to prevent the pressure drop in the supply line during transients, as all automatic control systems powered from a single power source.

The hydroaccumulator 91 is adapted to be connected to the pressure line 92 of the hydraulic line 93 by means of amplifiers 8 and 9 of the control signals in the off position, and also to the pressure line 58 by means of the valve 52 of turning on the stabilization unit and the hydraulic line 94 when the stabilization mode is off, which is necessary periodic charging of the hydroaccumulator 91 during system operation.

The valve 52 of the speed stabilization unit is designed in such a way that when the stabilization mode is off and the control signal amplifier 8 is turned on, one of the executive cavities

hydraulic cylinders 90 through hydraulic lines 95 and 86, amplifier 8 and hydraulic lines 97 are connected to a hydraulic accumulator 91 connected by a channel 94 with a power source 58, with

In this case, the opposite cavity of the hydraulic cylinder 90 is connected via hydraulic lines 98 and 99 through the amplifier 9 to the drain 100. When the stabilization mode is off and the control signal of the first control cylinder 9 of the said hydraulic cylinder 90 is turned on via hydraulic lines 95 when 96 , and the opposite cavity by

hydraulic lines 98 and 99, amplifier 9 and hydraulic lines 97 are connected to the hydraulic accumulator 91.

Consider the operation of the system when operating in the stabilization mode.

speed. The activation of this mode is carried out by the handle 48, with the help of which the required speed of the machine is set. When this valve 58 inclusion is in the position shown in

Fig. 1, the actuating hydraulic cylinder 90 of the pre-aligning speeds is turned off, and the executive hydraulic cylinder O of the Stabilizing Speed is ready for operation.

Consider the operation of the system when the switch is switched to the high voltage. The information signal about the need for switching, produced by the information-measuring unit 1, enters the main signal of the hydraulic valve 2. The control signal amplifier 9 and channel 15 reports the last the cavity of the control signal amplifier 8 with the pressure line 42. The amplifier 8 is switched on and connects its control cavity with the pressure line 17 via the throttle 24 and the channel 22 Now, if informetsionny even necessary signal transmission switching disappears, the processing actuator control signal will nevertheless prodslzhats.

In this position, the amplifier 8 will connect

one of the cavities of the actuating cylinder 70 of the stabilization unit by means of a hydroline 96 through the valve 52 of the inclusion, channel 69, as well as by means of a hydraulic line 9 / with a hydraulic accumulator 91 Last

emptied, displacing a portion of the working fluid into the cavity of the actuating cylinder 70, while the opposite cavity of the hydraulic cylinder 70 through the channel 68, the valve 52 of the inclusion, the hydroline 99 by means of the booster 9 is connected to the drain

100. As a result, the piston of the hydraulic cylinder 70 is displaced to the left, lowering the engine speed. This is a preliminary alignment of the angular velocities of the driving and driven parts of the friction clutches of the gearbox, which is necessary by the time the gearshift begins to top gear (Fig. 2, section TI).

In the same position, the amplifier 8 soy dinit executive hydraulic cylinder of 12 high gears with a choking line 17 through channel 18. The hydraulic cylinder 12 will be triggered and then by means of an effective if 1 mt prop propane blow of the yoke mechanism 44 a pyrex will occur; yuchenie on

rtK CluyiO rioponnuv /,

In the same position of the amplifier 8 of the endcap, the cavity of the amplifier 9 of the signal is upright connected to the drain 101 via the hydroline 16 and the amplifier 8. Thereby preventing the spontaneous triggering of the amplifier 9 from leakage through the 1 zolotniki elements.

In the second position of the piston of the actuating hydraulic cylinder 1-e, when its apr / - l mon is compressed, the valve 10, which controls the valve 10, is connected to the pressure line 1 7 through hydraulic lines 33 and 18 and i rose to increase 0. As a result, The pan 10 is triggered and moved to the second position. This position K0ii rpon valve 10 connects the operating cavity of time relay 14 to 27 L, causing relay 14 to empty. After emptying, it informs the torus of the control cavity of the amplifier 8 of the control sigal by means of the glandular joint JO with drain 29. The pressure in the end face of the amplifier 8 decreases , and under the action of the spring, the spool of the amplifier 8 returns to its original position, detaching the working cavity of the hydraulic cylinder 12 from the pressure line 17 and connecting it to the drain 19. Pro. | See if the emptying is performed by the leg of the hydraulic cylinder 12.

From the second position of the control valve 10, the oriovole cavity of force elp 9 is connected to drain 38 by means of pipelines 39 and 10. pr; e (a random power amplifier 9 is created; either from the leakage through the gold elements or in the case of information the signal for the subsequent shutdown from the hydroglot hydraulics, and at that moment, the process of switching the transmission from the previous information signal was still completed.

In addition, in the position when the time relay 14 is supported, the control of the control terminal 8 and 9 is connected to

discharge 29 through lines 30 and 31 and relay 14, which also excludes underdose / glymo; h this time is triggered by amplifiers. In the annex, in which the time relay 14 is empty, the hydraulic valves 2 and 3 are disconnected from the power source 42 by the relay 14. This also prevents the amplifiers 8 and 9 from turning on when one of the electro-octi-oi and 3 triggers, while the time relay 14 is completely It is not charged that will provide filtering of informational CHI during the transitional processes, three of them / one transfer.

5 After the power supply 1 my cylinder 12 was emptied and the j iif.ni piston was similarly taken care, the end face of the control valve 10 pgredit vg CGI, P ELINE 33 is associated with the word

G 32, and under the action of the spring, l; the counter valve valve 10 is located at the first position. At the same time, it is working. a time relay 14 is connected in a nanosecond by the line 2b by means of: a line / 6. and

5 relays are charged only after a chggs it is possible to work with informat-utsiopn: igna-r h. Lu1-cls;

IIOP J, 1, 1 And, GCH KPP at BS E 3 -jMeiil t IPPNIRp, o J mouth, yzvrasheno. OutcomeG my r, y.

Go1 wk pjr, liroyg. With orpnogo mode /, t.inrt t and g, g and lgl | tsii given set of inhalation. -web-: those bpo. Stab them; i-zotsii / orysp rig 2,

 mind t.- gok T)

i, in the rationalized resolution, of the position as MO is shown on the fi;, 1 handle 4d y ,, I CG - item h position required | my skorisg .. dpizhen1. . Poi tom profiled kul ik

0 7 n the lever 51 is set to the M. The shaft is turned counter clockwise crpeiKi-. Zol jr-nsh-na52 inclusions which poddny-1 orbii.,. I r / rezhin and pr-in-i position, sozdynyrt-lagistr and- 53 gtay n with hydrolink n C) 9 tax-discnstn: poryoraztel 53, and lanes 5BrcrR 1C (1.1 j jro-discrete P & R imaging through hydrochemical L7 with chorpon) sensor 45 speed1 | and o HonpeML but opt-0 Drosgee 1 m 4t backs V-ru, Art,; 01, STV At efsm 1IDROLIN5-85 klopinom 51 okg. orooe tiherj or, lim j6 guide G linig1 lch - from l, .icr-jan.i g ip nor

f (OLO-LI -O pV Or-iKH 48 (, G (

5 certain passage through the river. Seventh d (l .. cel i 46 Rugko.m) is fixed in a predetermined position with the emergency control device 50 Dag% l i i yyos and b, zchgz / yy discrete ftpv g-zoiette; depends on JT produce, gi ;; h t-aroc

45 and the flow area of the adjustable throttle 46. The spool 54 of the analog-discrete converter when moving the machine at a constant speed is in a state of equilibrium under the force of the working fluid pressure in the cavity 56 and under the force of the spring 55.

When switching to a higher gear, the pressure in cavity 56 increases, which is caused by an increase in the speed of the vehicle.

The spool 54 under the action of the increased pressure of the fluid in the cavity 56 will move to the right and connect the hydroline 59 to the end cavity 62 of the distributor 64 via the channel 60, and the end cavity 63 through the channel 61 - to the drain (in Fig. 1 the valve of the distributor 64 is depicted in the position corresponding to lower gear). The spool 64 will move to the right and connect the cavity 62 to the input 65 of the pulse generator 66, the output 67 of the pulse generator to the hydraulic line 69, and the hydraulic line 68 to the hydraulic line 87.

o From the moment the working fluid impulses 66 are fed to the inlet 65 of the generator 66, portions of the fluid begin to form at the outlet of the fluid 66 and are supplied to the piston cavity of the actuating hydraulic cylinder 70. At the time of giving each portion of the working cylinder, the hydraulic cylinder 70 moves through the channel 68, the distributor 64, the hydroline 87 is connected to the drain 89 via the on-off relay 71.

As a result, the piston of the executive hydraulic 70 moves, making a more precise adjustment of the engine's speed control in the direction of lowering it, thereby restoring the desired speed of movement. Regulation takes place until a given speed of movement is restored, at which the spool 54 of the analog-discrete converter 53 blocks its lines of the hydraulic lines 60 and 61.

The pulse generator 66 operates as follows. The signal in the form of a constant pressure level from the input 65 through the two-position relay 71 is supplied simultaneously to the end cavity of the relay 75 time through the hydraulic line 77 and to the battery 74 through channels 78 and 79. As a result, the battery 74 is charged, compressing the spring 76. a the time relay piston 75 moves to the left and at the end of the stroke CJGIO informs the working cavity through the hydroline 81 with the end cavity 80 of the spool 72 of the two-position relay 71, as a result

the spool 72 moves upward, compressing the spring 73, and overlaps the input 65 of the pulse generator. In this case, the time relay 75 is connected via hydraulic line 77 to the discharge 82, and the battery 74 to the output 67 of the pulse generator time relay 75 begins to empty. Holding the spool 72 in its highest position is done by the pressure force of the fluid

0 entering the cavity 80 from the input 65 of the pulse generator through the choke 83. The hydraulic line 81 is blocked by the side surface of the piston of the time relay 75. At the end of the emptying phase, the piston relay 75

5 times, the cavity 80 communicates via hydroline 81 to the spring cavity 76, which is connected to the drain. The pressure in the cavity 80 drops and the valve 72 moves downward under the action of the spring 73.

0 again the fill phase of the time relay. Thus, the time relay 75 controls the on-off relay 71, which periodically connects the battery 74 to the output 67 of the pulse generator,

5 disconnecting it from the supply mains (input 65)

As a result of the simultaneous use of the gearshift unit on the speed stabilization unit

0 automatic nepei. Transmission gearing is controlled by adjusting the GHF speed of the engine (such as the machine’s operating mode is not being used, for example, when

5 airopic and agricultural landings)

In the latter case, when there is no need for the speed control mode, the speed stabilization unit is turned off. With

0, the ego of the handle 48 is moved from the on position to the off position. The lever 51, kinematically associated with the handle AB, moves to the left (clockwise relative to the axis), and behind it moves

5 to the left and the valve 52 on, disconnecting the supply line 59 from the analog-discrete converter from the main line 58 to the unit. In addition, supply line 58 is connected by means of hydrolines 84 and

0 69 with a piston cavity of the actuating cylinder 70, the opposite cavity of which is connected1 via channels 68 and 85 with a drain 86. The piston of the actuating hydraulic cylinder 70 moves 5 to the extreme left position corresponding to the minimum speed of the de-iat & Cylinder 70 in the lth case is a constant length tie rod. Improving the quality of transients on the described stabilization mode

speed is achieved due to the fact that the output of the speed pre-alignment device is connected to the hydraulic cylinder 70 of the speed stabilization unit, and in the other modes of operation of the automatic control system - to the hydraulic cylinder 90, which is also installed in the accelerator control actuator. This reduces the speed control time during operation on speed stabilization mode.

Fig. 2 shows the characteristics of the functioning of the automatic control system when operating in the mode of stabilization of the SPEED AND P rvKLYUCHRchgm G MP

N + 1st gear. The dashed line changes the 0 g forgive V, V,., P when the speed stabilizer and the speed predivision device are turned off. The solid line shows the processes when the automatic control system is on.

The speed adjustment time T0 is made up of two times: Ti and V. (At a time Ti, the speed pre-alignment device provides a preliminary rough change in the speed of the drive motor (ypq) Adjustable stabilization unit during the time T2. In connection with heme, that both the speed stabilization unit and the device prior to / other speed equalization form control signals of the same character, they must be supplied to one executive officer in the speed stabilization mode. . N- well. This reduces the Yerem control speed.

In the remaining modes of operation i of the automatic control system of the speed and load modes of the self-propelled machine, when it is not necessary to maintain the speed of the machine at the post level, the device of preliminary speed equalization is connected to the executive hydraulic cylinder 90 (Fig. 1).

In this case, when switching gears, the rod of the hydraulic cylinder 90 is moved, changing the engine speed. After the switch is completed, the rod of the hydraulic cylinder 90 returns to its original position, restoring the initially set engine speed. The rod of the hydraulic cylinder 70 is in the constantly extended position and does not interfere with the accelerator control.

In the off-stabilization mode, the executive unit of the automatic pe - switching of gears

works in conjunction with a pre-leveling device.

Consider the operation of a preliminary leveling device at

example of switching to a higher gear. At that moment, when the control signal amplifier 8 will operate and occupy the leftmost position, by means of the valve 52 of turning on the speed-stabilizing unit,

0, which is also in the leftmost position, is one of the cavities of the executive hydraulic cylinder 90 of the device for pre-alignment of speeds through hydrolines 95 and 96, amplifier 8, and hydrolisation 97 g: oelinates with hydraulics of the Kcumul torus L, which is permanently connected at iMnopi ofi line 58 gp /, horn wider 94 and valve 52 including. At the same time, the cavity of the hydraulic cylinder 90 is opposite to the middle

0 one channel 98, valve 52 turning on i of line 99 and amplifier i 9 is connected to drain 100. As a result, the piston of the hydraulic cylinder 90 moves to the left, compressing the left spring, Engine speed

 which reduces the speed of the driving and driven parts of the transmission clutches of the gearbox before starting and at the time of the peg-key to the highest r-h Edach.

0 After a smooth automatic gear shift, the amplifier 8 is moved to its most advanced position. In this case, the cavities of the used /. Hydraulic cylinder 90 are connected to the drain 101 and

5 1 (V through amplifiers 8 and 9, and lines 96, 95 and 99, 95, respectively, as a result of its piston of the hydraulic cylinder 90, under the action of the left spring, returns the average of the field (i.e., restoring the original engine mode).

Similarly works systems; automatic control when shifting ne low gear. Suppose that the speed stabilization mode is on (valve

5 52 of the inclusion takes the position shown in figure 1).

In the event of an information signal about the need to shift to a lower gear from block 1

0, the electrohydroclic j triggers through the control channels 5 and 7, the control signal amplifier 8, the channel 16 communicates the end cavity of the amplifier 9 with the pressure line 42. The core turns on and connects its own

5, the control cavity through the hydroline 23 and the throttle 24 with the pressure line. In its position, the amplifier 9 connects the rod cavity of the hydraulic cylinder 70 to the cylinder unit with the hydraulic accumulator with a torch 9. And the hfpgzpolozhennuyu cavity with the drain 101.

As a result, the piston of the hydraulic cylinder 70 of the cr is displaced by the pressure of the liquid portion displaced by the hydraulic accumulator to the right, increasing the speed mode of the engine.

At the same time, the amplifier 9 will connect the executive hydraulic cylinder of the 13 lower gears to the pressure line 17 and will switch to the lower gear. Next, the pulse generator 66 will be put into operation, by means of which the predetermined high-speed mode of the engine is restored.

If the speed stabilization mode is turned off, the pre-alignment of the speed range during downshift is provided by the hydraulic cylinder 90 of the speed pre-alignment device.

In this case, the piston of the hydraulic cylinder 90 is displaced to the right, compressing the right spring, thereby increasing the engine speed.

After automatic gear shifting, all elements of the actuator and pre-alignment of speeds return to their original position (as shown in Fig. 1). The system is responsible for the development of a new control signal.

Claims (1)

1. The automatic control system of the self-propelled machine speed and load reclosures, containing information-measuring computer control gear, i gears, consisting of electrohydraulic valves, control signal amplifiers, control valves of hydraulic actuators, and relays time, the speed stabilization unit, which includes a speed sensor, made in the form of a hydraulic pump, kinematically connected with the driving wheels of the machine, a two-position control valve executive a speed stabilization cylinder with two control cavities, an analog-discrete converter, a two-position distributor, a pulse generator and a driver, a pre-alignment device consisting of a hydraulic accumulator and an actuating hydraulic cylinder with two control cavities installed in the accelerator control actuator and speed stabilization associated with the executive body, power source, pressure and discharge lines, in order to increase reliability By improving the quality of transients during automatic gear shifting, the speed control unit's on-off valve is configured to connect, in the first position, one of the control cavities of the executive hydraulic cylinder of the velocity pre-alignment device to the power source and accumulator, and the other control cavity to the drain hydraulic lines by means of signal amplifiers control, with both cavities of the stabilization hydraulic cylinder C erpsti — terti, in the second position both cavities - the motor yugg of the hydraulic cylinder of the preliminary expansion device - Bahi q).) STI is disconnected from the power source i:; and the pump accumulator; with slivi..1 lsh-iy pg srgz stvom amplifiers sshn nor WParlrmg 2 of the system according to claim 1, c g, and that “so that the hydroaccumulator torch is communicated to me with the pressure line through SAPI. Signs to it: control in their first position / i by means of the valve turning on the speed stabilization unit in its ir position with eum in the second position of one of the amplifiers 1 also in the B of the full position of the accumulator valve ot- keys from the napgr line Vrp Af .M t