DE2023846A1 - Control device for hydraulically driven implements on an agricultural tractor - Google Patents

Description

Messerschmitt-Bölkow-Blohm Münchör ;., May 11, 1970

GmbH Rd / Κθ

Hlofcv ^ 9:
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Control device for hydraulically driven tools on a farm tractor

The invention relates to a control device for hydraulically driven implements on an agricultural tractor, which primarily include a three-point linkage and several optionally attachable devices.

In known devices of the type mentioned, a special operating lever is provided for each implement, wherein Due to the large number of levers required, a relatively complicated structure for the entire control device results and the operation of the device is very difficult because of the possibility of incorrect switching.

On a control device of the type mentioned, in addition to a three-point linkage acting on one or both sides working cylinder z. B. for a power lift, as well at least one hydraulic motor are to be driven in different combinations at the same time, the The object of the invention is to provide a control device that is relatively easy to operate with relatively little overall effort create that only a small number of controls requires.

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The object is achieved in a control device of the type described in that a sleeve rotatably mounted in a preselection control cylinder is provided with a shift gate in which a shift lever is guided, which is connected to a control piston rotatably and axially displaceably mounted in the sleeve Rotary movement is communicated to a further actuator assembly which cooperates with the preselection control cylinder of a sleeve and its control piston. With the exception of the operating means for the three-point linkage thereby forming Advantageously, said shift lever is the only operating element of all the other can be connected to the Aokerschlepper hydraulic working equipment, whereby the operator of the device is substantially simplified. The geared association between the control piston actuated by the gearshift lever on the one hand and the further control unit on the other hand makes it possible to design the two control units mentioned in such a way that any combination of working devices corresponding to practical requirements can be operated at the same time.

In an expedient development of the invention is included the rotary movement of the control piston with gear means transferred to another control piston, which is axially displaceable and / or rotatable in another Steuter cylinder is stored, with between the other Steiierkolben and A rotatably mounted further sleeve can be arranged with the further control cylinder, which can be driven with means the rotary movements of the sleeve of the preselector cylinder are communicated are. This form of training enables @s in one single structural unit, the relatively simply designed hydraulic and gearbox. To arrange means and 'with help a preselection handle that comes with the sleeve of the Vorwalilsylinders connected, the Einriolittmg for the enterprise Implements or equilateral. Operation of combined Απ

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adapt tools. .

According to a further development of the invention, the gearshift lever is rotatably mounted about its longitudinal axis, with its rotary movement acting on the sleeve of the preselector by means of geared means your cylinder is transferred. By this arrangement, the feasible with drive means known per se is, the separate arrangement for the handle of the preselection holder is omitted without due to the different Degrees of freedom of the switching handle there is a risk of operating errors. In an expedient embodiment of the invention have both the preselection control cylinder as also the other control cylinder outputs for one-sided and for double-sided working cylinders, with instead Working cylinder acted upon on one side also the connection of a hydraulic motor (mowing motor), for example is possible. The claimed assignment of the outputs enables a relatively simple design of the hydraulic units.

According to a further development of the invention, an additional and with a cam disk is for the drive of a three-point linkage connected shift lever is provided, the cam having a rotational degree of freedom and together with a further cam disk connected to a feedback, likewise with a rotatorisohen degree of freedom the position of a third cam disk mounted with two translational degrees of freedom determines which one to the first two cams and one under spring force standing valve arrangement. A line connection from a hydraulic pump to a working cylinder is only produced if both shift levers, d. H. both the shift lever for the control arrangement and the additional shift lever for the three-point linkage take a corresponding position. For work that one

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Simultaneous or alternating operation of the three-point linkage and other work equipment ©, is in this · Arrangement significantly reduces the risk of operating errors, because after setting the preselection only the two mentioned shift levers have to be operated.

In an expedient development, the valve arrangement is so daß.die third cam after the opening of a first valve and overcome, the game of a -second valve against the! Traft the closing spring of the second valve loading ψ wegbar is the first with the. Valve switched in parallel. is. With this arrangement it is ensured in particular that the power lift is loaded without jolts irrespective of the operation of the shift lever assigned to it.

According to a development of the invention, the control device has at least one control line to "the one of the Control cylinder leads to an idle device, which in one of the control cylinders umgelisndexi idle line relative large cross-section is arranged. With this facility prevents the print medium from being over relatively idle high resistances of the control device and of the lines connected to it ^ is carried »due to the applicable relatively large cross-sections dor idle line can the idle loss © can be reduced considerably.

In a special development of the invention, the control pistons are spring-bound and in their neutral position held in their two end positions by locking devices, their holding force when exceeding a specified working pressure of the hydraulic medium is also exceeded. With the help of this device, a reset takes place the control piston in the neutral position as soon as, for example an implement is overloaded or the working piston assigned to it has reached its end position.

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An exemplary embodiment of the invention is shown in the drawing shown.

Fig. 1 shows the overall arrangement of a control device in longitudinal section, the invention not relating to details are omitted or schematically simplified are posed.

The device and its mode of operation are described below with reference to the drawing. ■

In a preselection control cylinder 1, a sleeve 2 is rotatably mounted, which is used with a handle 13 to preselect the connected hydraulic working devices to be operated, of which working cylinders 60 to 6 * 1 acted on one side, a cutting motor 62 and working cylinders 63 to 6k acted on on both sides are schematically simplified are shown. A control piston 5 is rotatably and axially displaceably mounted in the sleeve 2 and has a piston rod Ik which penetrates the end face of the sleeve and is provided with a switching lever 4 and a gearwheel 6. A bevel gear 11 and a shift gate 3 are also attached to an end of the sleeve 2 protruding from the preselection cylinder 1. The bevel gear 11 is in engagement with another bevel gear 12, which is attached to the end of a further sleeve 10 protruding from a further control cylinder 9, in which a further control piston 8 is also rotatably and axially displaceably supported, whose from the further. Sleeve 10 protruding piston rod 15 is in engagement with the aforementioned gear 6 via a rack 7. Instead of the handle 13 to the device code "ine may be made while k in the drawing, not shown kinematic connection between the sleeve 2 and the shift lever with the shift lever about its longitudinal axis k rotatably on the piston rod · \ k is stored. In the one further control piston 8, the further control cylinder 9 and the other

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Sleeve 10 comprehensive control unit can be on the arrangement the further sleeve 10 and the gears 12 and 11 for geared connection of both control units with simplified Requirements for the arrangement are waived, d. H. if the entire control system is only used for a relatively small number of implements that are acted upon on one and two sides is to be interpreted.

After preselection of the implements by .dl © handle 13 or the shift lever 4 is used to raise and lower one Three-point linkage simplified with the help of a schematically

power lift 45 shown by actuation of a further shift lever 3I This additional shift lever is connected to a cam disk 30, which has a rotational degree of freedom and which, together with another cam disk 32 connected to a return, also has a rotational degree of freedom, the position of a third cam disk 34 determines which is applied to a valve assembly. In the "neutral position" of the lever 31, a valve 36 is opened against the force of its spring 4o just enough for a second valve 38 to remain closed while utilizing the play 37. Part of the oil delivered by the tractor's pump 50 passes through a systematic

w simplified idle unit 66 and a control line 65 via the two control units. 1, 2, 5 and 8, 9, 10 into the valve arrangement 35, where it is passed through the opened valve 36 into the oil sump 41. Due to the occurring in the idling device 66 Differsnzdruck this ine for the light exiting from the pump 50 oil © line connection are 67 "68 relatively large cross-section and low Strämungswiderstand ^ free _B which returns also in d @ n oil sump 41st In the two control units H ₈ 2, 5 and 8, 9 »10, there are only very low oil pressures. The oil in the working cylinder of the power lift 45 is passed through a check valve 46 0 © wi © which is fed by its spring 39

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Further valve 38 which is held closed and which blocks the valve arrangement 35.

If the shift lever 3I is now moved in the direction of the lifting arrow, the valve 36 of the valve arrangement 35 closes as a result of the sequence of movements taking place via the cam disks 30, 32 and 34, the differential pressure also prevailing in the idling device 66 collapsing and the idling line 67 and 68 is blocked. The pump 50 now delivers oil from the oil sump IfI, which is shown in the drawing in the same manner of representation and with the same reference numerals, in order to avoid long line paths at different points. The pressurized oil passes through line i6 and arrives via bores 17 and 18 of the further control cylinder 9 and a channel 19 of the further sleeve 10 via lines 20 and 21 to an inlet 22 of the further preselection control cylinder 9 through a bore 23 of the further preselection control cylinder 9 and a further bore 24 of the further sleeve 10, the oil passes via an annular groove 25 and an axial bore 26 of the further control piston 8 to a further annular groove 27, from which it passes via bores 29 and 28 of the further sleeve 10 and the further control cylinder 9 a pressure oil line 42 arrives at an inlet 43 of the preselection control cylinder 1. fj

Via a preselection control cylinder 1 and its sleeve 2 penetrating bore 44, an annular groove 47 of the control piston 5 and its, axial bore 48 and its further annular groove 49 and a preselection control cylinder 1 and the sleeve 2 penetrating bore 69, which via a line 70 with the check valve 46 is connected, the power lift 45 is acted upon. The piston 7I of the working cylinder is while lifting in Riohtung. The line system described here is also a known flow divider 73 connected via a line 72. From flow divider 73 Furthermore, another line 74 leads via a bore 75

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the further control cylinder 9 and the further sleeve 10 to the channel 19 of the further sleeve 10, which, however, is blocked. After reaching the new position of the three-point linkage the eccentric disk 32, which is firmly connected to the return guide 33, brings about the "neutral position" again In this way, the pump is relieved and the three-point linkage is hydraulically blocked.

When the additional shift lever 3I is moved in the lowering direction indicated by the arrow, the two valves 36 and 38 of the valve arrangement 35 are opened. The back "ter the piston of the power lift 45 oil contained flows under pressure of the pressure acting on the piston devices weight over a line 76 'a lowering throttle 771, the open valve 38 back to the sump 41", the open valve 36 causes this discharge, already described, the Pump 50. The lowering process is terminated after reaching the new end position via the return 33 analogously to the previously described manner.

All other attachments are operated with the aid of a single shift lever h assigned to these devices. For this purpose, the sleeve 2 of the preselection control cylinder ^ with the aid of the handle 13 »which can be kinematically connected to the shift lever h in the manner described above, is brought into a position assigned to the implement, with a known lock, not shown in the drawing, temporarily solve is. The shift gate 3 firmly connected to the sleeve 2 of the preselection control cylinder 1 is brought into a position in which the shift lever h is located in a recess 78 assigned to the implement to be operated. Corresponding to the connected working device, the recess 78 has a limitation within which the shift lever h can be displaced and / or in the axial direction of the piston rod lh

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is rotatable about this axis. The preselection is independent of the operating state of the engine; it can take place with the engine stopped or running, with the pump 50 remaining unloaded. In the example shown, the working cylinder 61 acted upon on one side is provided for actuating a front loader, and a working cylinder 6h acted upon on both sides is provided for actuating a front loader shovel. After the preselection made by setting the sleeve 2, the control pistons 5 and 8 are in the neutral position shown in the drawing, which is secured with the aid of a detent 79. In the manner described above, the valve arrangement 35 is also in the neutral position and the pump 50 is relieved.

When the front loader is lifted, the switching lever k is pivoted out of the plane of the drawing towards the viewer. Driven by the toothed wheel 6 and the toothed rack 7, the further control piston 8 moves downward until a locking device 80 engaging the piston 8 engages in an upper annular groove 81 of the piston 8.

Due to the position of the further control piston 8 in the further sleeve 10, a bore 82 penetrating the named parts and the further control cylinder 9 is interrupted - and thus also the control line 65 described above, with a switchover in the idle device 66 through which the from the pump 50 delivered oil via the lines 16, 20, 21 also described to the inlet

22 of the further control cylinder 9 arrives. About holes

23 and Zk of the further control cylinder 9 and the further sleeve 10, and an annular groove of the other control piston 8 reaches the pressure oil to the output 53 ^dös further Steuer.-cylinder, on which the one side is acted upon working cylinder 6i the front loader rocker is pivoted and moves the

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Piston of the working cylinder 6i in the lifting direction. The idling device 66 is switched so that the lines 72 and 74 are under the oil pressure supplied by the pump. In addition, the annular groove 27 of the further control piston 8 and the associated bore 29 of the further sleeve 10 do not coincide, as a result of which the connection to the check valve k6 leading via the lines 42 and 70 is interrupted. The lines 72 and 7 ^ and the blocked line 73 are under oil pressure via the quantity distributor 73. The lifting process can be interrupted at any time by returning the shift lever 4 to its neutral position. However, if this lever is left in its position, which is held by a locking device 80, the piston of the working cylinder 61 finally reaches its end position, whereby the oil delivered by the pump 50 is diverted into the sump 41 via an overflow valve (not shown in the drawing) will. The pressure difference occurring at the overflow valve also acts with means not shown in the drawing on the lower piston side 83 of the further control piston 8, whereby the force of the locking device 80 is exceeded and the piston 8, supported by the force of a spring restraint 84a and b, moves into its Neutral division moved back. The pump 50 is relieved in the manner described above.

To lower the front loader, the switch lever 4 is moved backwards, whereby the control piston 8 is driven via the gear 6 and the rack 7, executes an upward movement and the snap lock 80 assigned to it engages in a lower annular groove 85 of the piston. The oil located behind the piston of the working cylinder 6i is pushed back into the outlet 53 under the action of the device and reaches the further control piston 8 of an annular groove 89 and the inner wall of the weifcer @ a sleeve

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formed annulus over a further sleeve 10 and the further control cylinder 9 penetrating bore 90 and Lines 86 and 87 return to the oil sump 41 via an adjustable lowering throttle 88.

A working cylinder 6k acted upon on both sides is provided for attaching a front loader shovel. For lifting the front loader shovel, the setting of the preselection by means of the handle 13 remains unchanged, while the control piston 5 comes into engagement with the locking device 79 assigned to it with an annular groove ^ λ. Due to the lateral offset of the,

Control piston 5 is interrupted the preselection control cylinder 1, the sleeve 2 and the control piston 5 penetrating bore 92 and the control line 65 is blocked. The practically pressureless short circuit of the oil circuit is switched off in the manner described above. The oil coming from the pump 50 now makes its way in the manner described when lifting the front loader to the input kj of the control cylinder 1 and from here passes through a bore kk penetrating the preselection control cylinder 1 and the sleeve 2 and an annular groove ^ 7 of the control piston 5 »As well as another bore 93 penetrating the preselection control cylinder 1 and its sleeve 2 via an output line 59a to the right piston side of a double-sided working cylinder f) 6k, the piston rod of which is connected to the front loader shovel in a manner not shown. The oil located on the left side of said piston can be fed via line 59b, a radial bore 9k through the preselection control cylinder 1 and its sleeve 2 and a further radial bore 95 through the two named parts via lines 99 and 100 and the lowering throttle 88 escape into the swamp kl. If the lifting process is not ended by manual actuation of the shift lever k , a return to the neutral position takes place analogously to the example described above, as soon as the working piston of the working cylinder 64 reaches its end position, with the overpressure building up

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the pressure oil supplied by the pump 50 is likewise discharged into the oil sump kl in the manner previously described.

The pressure on the overflow device, not shown, also acts in a manner not shown on the left side 97 of the control piston 5, which is returned to the neutral position against the force of its locking device 79 and supports its spring restraint 9f a and b. When lowering the front loader shovel, the shift lever h translates in the opposite direction »that is to the right. shifted, the control piston 5 of the preselection control cylinder 1 follows this movement. The preselection control cylinder 1 is supplied with pressure oil at the inlet kj via the bore kk , which leaves it again via the bore 9 ^ and enters the working cylinder 6k acted upon on both sides on the left-hand side. The return of the oil located on the right-hand side in the working cylinder 6k takes place via the bores 93 and 98 of the preselection control cylinder 1, as well as the lowering throttle 88. The return of the control piston 5 to the neutral division and the switchover of the pump circuit from idling to load © takes place analogously as described for lifting the front loader bucket.

In addition to the working cylinder 6 ^ for the front loader shovel, a further working cylinder, which is acted upon on one side or on both sides, can be connected for a reversible plow, a plow wheel or a tipper. The control of this cylinder then takes place analogously to the manner described, where the shift lever k is to be inserted into another recess of the shift gate 3, not shown in the drawing, which is arranged in front of or behind the recess described.

A mowing motor 62, which must be operable at the same time as a mowing elevator, is connected to one output 59a for the working cylinder 6k acted upon on both sides, where-

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at for the mower lift. working piston pressurized on one side. 60 is presented, which is at an output 51 of the further Control cylinder 9 is connected. In the two oil circuits there is a flow divider known per se 73 switched. The control processes for the mower motor and the mower lift run analogously to the examples described above. The one intended for the mower motor and the mower lift Recess 78 of the shift gate 3 allows one Pivoting movement of the lever about the longitudinal axis of the control piston 5 »with the further control piston 8 being a translational one Moves and controls the raising and lowering of the mower elevator, as well as a translatory movement in Axial direction of the control piston 5 * with the latter being the input and turning off the mower controls.

The lowering throttle 88 can in a manner known per se with devices be provided to adapt to the connected work equipment »for example with adjusting elements, which are kinematically connected to the preselection control cylinder or there can be several, the individual working devices adapted switchable lowering throttles are used. Compared to arrangements in which each working unit is assigned its own control lever, the The arrangement described the use of more than two lowering throttles also in the last-mentioned application example.

Additional working cylinders that are acted upon on one or both sides can be connected via the unused outputs 5% » 5 ^, 55 and 56.

Both the preselection control cylinder 1 and the further control cylinder 9 and the valve arrangement 35 can be enclosed by a common housing (not shown in the drawing) and form a structural unit, these being the

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Control unit comprehensive unit also with one known per se and primarily at the left end of the preselection control cylinder 1 arranged device can be provided aur overload protection. This overload protection also responds if any work device in the neutral position (blocked position) is overloaded learns. In particular, this also applies to tools that are connected to the three-point linkage are in the case of the so-called position control.

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Claims (1)

EM 8.23 / 68 - 15 - 11.5.7O '/ Rd / Κβ Claims Control device for hydraulically driven tools on an agricultural tractor, with a three-point linkage and several optionally attachable devices include, characterized in that a sleeve (2) rotatably mounted in a preselection control cylinder (l) is provided with a shift gate (3), in which a switching lever (4) is guided, which is rotatably and axially displaceably mounted in the sleeve with a Control piston (5) is connected, the rotary movement of which a further, with the preselection control cylinder (1) of the Sleeve (2) and its control piston (5) cooperate Control unit (8, 9 and 1O) is communicated. 2. Device according to claim 1, characterized in that the rotary movement of the control piston (5) with geared means (6 and 7) on one further control piston (8) is transmitted, which is axially displaceable and / or rotatable in a further control cylinder (9) is stored. 3. Device according to claim 2, characterized «that between the further Control piston (8) and the further control cylinder (9) a rotatably mounted further sleeve (IQ) is located, which communicated with geared means (11 and 12) the rotary movements of the sleeve (2) of the preselection control cylinder (-1) are. k. Device according to one of the preceding claims, characterized in that the switching - 16 - 109851/0427 EM 8.23 / 68 - 16 - 11.5 »70 ί & lever (4) is rotatably mounted around © eis © LämgsaeJas® and its rotary baxfegumg is geared to the 'sleeve (2.) of the preselection®t © uerzylind © rs (1) transformer, '. Direction according to eia © md © r worh © rgeh®ndem Asasiprüsh ©, thereby gekenmg © i © te.net that your © control cylinder (i and 9) outputs (5I to 57) ^^ r one-sided and outputs (58a and b) for ^x working cylinders (60 mad 64) pressurized on both sides 6. Eiari © SitBS! IiS after eisaoa of the Tosrhor-going carrion ₈ da «by kennseiehnet ₉ that a drive for the three-point stage © @in SW-SStSlXcIiQZ ¹ and with one net, where the Kttr ^ asa ^ eSieifoe (30) 0ia © si FreilieitSigrad auftir © is vmA amsaEiaem with a further and with a return (33) "^ earfousdeaesa. Kur ^ emselieibe (32), also with © isa © sa rotatorisefeesa degrees for · © ISA © itsgrad _B with the position of a sisroi traaslatoris © li © 2i freedom ©. stored third JSiarv@sä.s©li©ibe (3 ^) l3 © stiiarait ₀ "rich sin both © ratgettaBaf © n Kiuur ¥ "etts © laeib © 3m (30 maad 32) and a« mter spring force st © feeadea VeatilauaordEmiag, whereby with eatspr © © ls. © mdQr St © ll «jag b © id © r S © halth. © b ^ l (4 and 31) via .the tno »itaiam actuated ©» Eisuriohtuagesi (i, 2, 5 uad 8 ₉ 9si 10) © i »e conduit connection ^ ~ ψ & ά © iaer hydraulic pump (50) auia power generator of the three-pin rod8 is made . Means: xaaeh claim 6, characterized g k © © η η _β is characterized in that the third Karrouscheibe (3 ^) by opening a first Yentils (36) and overcoming of the game (37) ® ± n @ a second ®ntll ¥ @ (38 ) ^ ®g®n the force of the closing spring of the »reiten Yantlis (38) can be moved, which is connected in parallel with the first valve (36). - 17 - 109851/0427 EM 8.23 / 68 - 17 - 11.5.70 Rd / Κθ 8. Device according to one of the preceding claims, characterized in that it has at least one control line (65) which leads from one of the control cylinders (9) to an idling device (66) which is in an idling line bypassing the control cylinders (1 and 9) (67 and 68) is arranged with a relatively large cross-section, · Device according to one of the preceding claims, characterized characterized in that the control piston (5 and 8) are spring-tied in their neutral position and by locking devices in their right and left end positions (79 and 80) are held, the Haltelcraft when exceeding a predetermined working pressure of the hydraulic medium is also exceeded. 109851/0427. L e r s e i t e