DE1052315B - Gearbox with hydraulic control device for driving lifting vehicles - Google Patents

Description

GERMAN

KL. oils 1U7

INTERNAT. KL. B 65 g

PATENT OFFICE

C7959 XI / 81e

REGISTRATION DATE: JULY 28, 1953

NOTICE
THE REGISTRATION
AND ISSUE OF THE
EDITORIAL:

MARCH 5, 1959

The invention relates to a transmission with hydraulic control device, in particular for Drive of lifting vehicles with a hydraulic torque converter, with intermediate shafts for reversing the direction of rotation and with several gear ratios that can be shifted by means of dog clutches.

There are hydraulic vehicle drives known which, in addition to a main drive motor, which is a combustion or electric motor, as essential elements hydraulic pumps, hydraulic motors, Control and regulating devices as well as the corresponding binding and conduction means for the hydraulic fluid contain. For example, there can be two hydraulic units, one of which one works as a pump and the other works as a motor. It is also possible to use several hydraulic motors, z. B. for single wheel drive, to switch in parallel or in series, the direction of rotation by appropriate Reversal of the pressure medium flow can be reversed and thereby achieved a braking effect can be that the motors are disconnected from the pump and temporarily act as pumps an overflow valve work with adjustable pressure. The drive is by individual hydraulic motors also known for trucks. Here, for example, the hydraulic system also has two pumps different flow rates, a centrifugal regulator that controls solenoid valves and a control spool each for each traction motor. With such an arrangement it can be achieved that everyone Motor can stand still and run forwards or backwards independently of the other.

In addition to such fully hydraulic drives, transmissions are known in which the torque is hydraulic or directly mechanically to the output point, for example to the vehicle axle can be. With the appropriate arrangement of hydraulically operated multi-plate clutches and the Required controls can be such a transmission in the forward direction and in the reverse direction switch under load.

Especially when operating forklifts and similar vehicles for picking up, transporting and placing loads, great demands are placed on the mobility of the vehicle, which only satisfactorily fulfills drives which are specially adapted for these purposes can be. When using lifting vehicles, a very responsive control for Requires the drive, which makes it possible for the driver to be very precise and centimeter by centimeter Approach loads or parking spaces. Here, the drive elements must not contain any impermissible Be exposed to wear and tear, and the vehicle operator's gearbox

with hydraulic control device
for driving lifting vehicles

Applicant:

Clark Equipment Company,
Buchanan, Me. (V. St. A.)

Representative: Dipl.-Ing. W. Kuborn, patent attorney,
Düsseldorf, Tonhallenstr. 8th

Claimed priority:
V. St. v. America July 29, 1952

Charles Arthur Cook, Jackson, Mich. (V. St. A.),
has been named as the inventor

must be protected from excessive stress on individual parts of the body, such as the legs. Such overuse can occur, for. B. result if the driver through the construction of the Vehicle is forced, the creeping movement of the vehicle, which is very often required in the course of the work When the drive is engaged, it can be controlled by applying the brakes to a greater or lesser extent.

The task of creating a drive that is particularly suitable for lifting vehicles, the one mentioned Requirements met is solved by the invention in a simple manner.

The transmission according to the invention with a hydraulic control device has two intermediate shafts hydraulically operated clutches, by the selective switching of each one of the Intermediate shafts can be connected to the transmission input shaft. In one through a pressurized fluid source A first and a second control valve are located in the hydraulic fluid circuit, one or the other clutch being acted upon with hydraulic fluid by the first control valve and can thus be operated while the connecting line is through the second control valve between the first and the second control valve either with the pressure source or with the sump can be connected. This creates a mechanically switchable transmission gear from the input shaft uncoupled so that the gear ratios can be switched in this state.

809 768/322

The invention offers the particular advantage that the braking process begins immediately with the coupling process can be connected. The second control valve has a hydraulic actuation device, which is connected to a hydraulic brake system of the lifting vehicle in such a way that when Pressing the brakes at the same time automatically releases the one in use Coupling takes place and when the brakes are released this coupling is automatically brought back into the use position will. This allows the power transmission between the input shaft and the output shaft be interrupted or switched on again very quickly and inevitably to put the vehicle in to move very small distance intervals forwards or backwards without, for example, the in The main drive motor that is still in operation is disrupted, causing the load to be raised or lowered.

The second control valve can also be operated by hand.

The first control valve can also assume a third position in which the one to the clutches leading hydraulic fluid lines are connected to the sump.

The pump provided in the hydraulic control device for returning the pressure fluid in the torque converter also serves as a pressure source for the control device. A first check valve is provided in the line leading to the torque converter, which is set to a pressure which is higher than that for a favorable efficiency of the torque converter and sufficient pressure to operate the clutches. Behind the first check valve branches a return line bypassing the torque converter with a second check valve which limits the fluid pressure in the line to the torque converter upwards. In the return line between the torque converter and the sump is a third check valve provided that the fluid pressure in the line to the torque converter down limited. The second and third check valves are adjusted so that the liquid pressure in the is maintained for a favorable operation of the torque converter required range.

The drawings illustrate several embodiments of the invention.

Figures IA, 1B and 1C show juxtaposed a vertical longitudinal section through a transmission according to the invention;

Fig. 2 is a schematic representation of the transmission shown in Fig. 1 and shows the geometric Arrangement of the various gear shafts;

FIG. 3 illustrates a partial cross-section along the line 3-3 in FIG. 2, seen in the direction of the arrows;

4 shows a view of an embodiment of the control valve unit seen from above;

FIG. 5 shows an end view of the valve unit according to FIG. 4;

Fig. 6 is a section through the valve unit along the line 6-6 in Fig. 4 looking in the direction of the arrows ;

FIG. 7 shows a section through the valve unit along the line 7-7 in FIG. 4 in the direction of the arrows seen represent;

FIG. 8 shows a section through the valve unit along the line 8-8 in FIG. 4 in the direction of the arrows seen;

FIG. 9 shows, in a schematic representation, an embodiment of the control device with that shown in FIG Recognize valve arrangement;

Fig. 10 shows in section a further embodiment of the control valve unit;

FIG. 11 is a schematic illustration of a further embodiment of the control device with the in FIG Fig. 10 shown valve arrangement.

In Fig. 1A, at 1 is an engine flywheel housing

ίο indicated that encloses a flywheel 2 that in turn fastened by means of screws 3 at the end of the crankshaft 4 of an engine or a prime mover is. On the outer periphery of the flywheel 2 is in a suitable manner, for. B. by welding, a externally toothed ring gear 5 attached, which is optionally driven by a starter motor of known design can be.

Behind the engine flywheel 2 is a fluid torque converter, generally indicated by the reference number 6, which is arranged within a housing 7 which is fastened to the flywheel housing 1 by means of screws T. The fluid torque converter 6 comprises a pump housing 8 which is fastened to the flywheel 2 by means of screws 9 so as to rotate together therewith. The pump housing 8 comprises a hub part 8 ′ and the components 10. The fluid torque converter 6 further comprises the turbine elements 11 which are fastened to a hub part 12.

which in turn with the front end of a horizontal transmission input shaft extending axially to the rear 13 is wedged. In addition, the torque converter 6 includes reaction elements 14, the by means of a brake, generally designated by the reference number 15, effective in only one direction are attached to a socket part 16, which is arranged concentrically to the input shaft 13 and on its rear end is attached to a flange part 17, this flange part by means of screws 18 is attached to the housing 7 of the torque converter. The fixed socket part 16 is used to support the hub part 8 'of the pump housing 8.

A liquid pump arrangement generally indicated by reference numeral 20 is outside of the stationary socket part 16 arranged concentrically with the latter and attached by means of screws 19 attached to the flange part 17. The pump 20 supplies pressure fluid for the control device according to the invention, which is described in detail below. As an inlet for the hydraulic fluid for the torque converter 6, a radial liquid channel 21 formed in the flange part 17, an in the fixed sleeve part 16 formed axial fluid channel 22 and one in the one-way brake 15 provided opening 23, which guides the liquid to the pump 10 and the turbine elements 11. as The exit of the liquid from the torque converter 6 is an opening 24 in a support part 25 provided, which is arranged concentrically to the input shaft 13 and in a suitable manner, for. B. by Welding, is attached to the pump housing 8. From the opening 24, the liquid passes through a with the reference numeral 26 generally designated check valve in one formed in the input shaft 13 Liquid channel 27. The channel 27 is in the fixed socket part 16 and the flange part 17 provided liquid channel 28 in connection. The already mentioned check valve 26 comprises a socket part 29 which is inserted into the channel

L KJO & J 1 O

27 is inserted, a spring 31 normally pressing a ball 30 against one end of the socket part 29. The check valve 26 is set to a relatively low pressure of, for. B. set about 1.4 kg / cm ² .

At the rear end of the torque converter housing 7 is a transmission housing by means of screws 33 34 attached. The housing 34 has on the top a removable cover part 37 to a To provide access to the interior of the housing.

The already mentioned transmission input shaft 13 is mounted in a ball bearing 35 in the front End wall of the transmission housing 34 is held. Inside the gear housing 34 is at the end of the Transmission input shaft 13 has a gear 36 formed. Inside the gear housing 34 are above the Axis of the transmission input shaft 13 on both sides of a vertical plane containing this axis two intermediate shafts 38 and 39 are arranged.

To make the illustration clearer, the intermediate shaft 38 in Fig. 1B is out of its normal position been swung out. The front end of the intermediate shaft 38 is mounted in a ball bearing 40, which is held in the front end wall of the gear housing 34. To store the At the rear end of the intermediate shaft 38, a ball bearing 41 is used, which is inserted into the rear end wall of the transmission housing 34 is installed. On a placed on the intermediate shaft 38 bushing 38 'is in the vicinity of the front end wall of the gear housing 34 a gear 42 is mounted, which with the gear 36 on the rear end of the transmission input shaft 13 is engaged. ·

The gear 42 can optionally with the aid of the coupling means indicated generally at 32 the intermediate shaft 38 are coupled. The gear 42 includes an axially rearwardly extending one tubular hub part 43 which has straight wedge tracks 44 on its outside. The Keilbahnen 44 carry a plurality of annular, radially extending clutch plates 45 which extend longitudinally can move the wedge tracks axially. On the intermediate shaft 38 is behind the hub portion 43 of the Gear 42 attached to a cylinder assembly 46 having an axially forwardly extending tubular Section 47 includes. This tubular section 47 extending in the axial direction engages over the clutch disks 45 and has straight wedge tracks 48 on its inside, which one . Carry a plurality of clutch disks 49 extending in the radial direction and extending along the wedge tracks can move axially. The clutch disks 49 alternate with those arranged in between Clutch disks 45 off. An annular end plate 50 is located on the inner wedge tracks 48 arranged sliding; this plate is subject to movement in one direction by a retaining ring 51 prevented.

The cylinder 46 comprises an annular cylinder part 52 in which an annular piston 53 extends axially can move. The collet 53 serves to connect the clutch disks 49 with the clutch disks 45 in To bring frictional engagement in order to couple the gear 42 with the intermediate shaft 38. The actuation of the Piston 53 takes place by optionally admitting pressure fluid into cylinder 52. For production a connection between the cylinder 52 and a pressure fluid source are used in the cylinder arrangement 46 formed liquid channel 61, a liquid channel provided in the intermediate shaft 38 62, a fluid channel 63 in a built into the rear end wall of the gear housing 34 Liquid distributor hub 64 and a liquid channel 65 formed in the gear housing cover 37. An end plate 57 is fastened to the cover part 37 and the gear housing 34 by means of screws 58. One in the end plate is used to supply oil for cooling the clutch plates 45 and 49 57 provided opening 56, a liquid channel 59 formed in the intermediate shaft 38 and radial Openings 60 in the hub portion 43 of the gear 42 and in the socket 38 '.

On the intermediate shaft 38 is between the ball

bearing 41 and the cylinder assembly 46 a gear 66 attached. As can be seen from Fig. 2, this is Gear 66 meshes with a gear 67 which is keyed to an output shaft 68, the axis of which lies below the transmission input shaft 13 in the same vertical plane as the axis of the latter Wave. The front end of the output shaft 68 is mounted in a tapered roller bearing 69 which is built into a radial wall 70 of the transmission housing 34. The rear end of the output shaft 68 is mounted in a tapered roller bearing 71 built into the rear end wall of the gear housing 34.

The aforementioned intermediate shaft 39 is shown in FIG. 3 at its front end in a ball bearing 76 mounted, which is installed in the front end wall of the gear housing 34. The back end of the shaft 39 is mounted in a ball bearing 77 built into the rear end wall of the gear housing 34. on the bushing 39 'placed on the intermediate shaft 39 is in the vicinity of the front end wall of the transmission housing 34, a gear 78 is mounted, which is inserted into the gear 36 at the rear end of the transmission input shaft 13 intervenes.

The gear 78 can with the help of the generally indicated at 72 coupling means optionally with the Intermediate shaft 39 are coupled. Like the gear 42 on the intermediate shaft 38, the gear has 78 has a tubular section 79 extending axially to the rear and having straight ones on the outside Splines 80. The splines 80 carry a plurality of radially extending annular Clutch disks 81, which can move axially on the spline. On the intermediate shaft 39 is behind the hub 79 of the gear 78 a cylinder assembly 82 is attached, one axially forward extending tubular portion 83 comprises. The tubular section 83 engages over the clutch plates 81 and has a straight spline 84 on its inside, on which a plurality of radially extending annular clutch plates 85 are arranged, which extend along the keyways can move axially. The clutch disks 85 are alternating with the clutch disks 81 arranged. The internal spline 84 also carries an axially movable clutch plate 86, which by a retaining ring 87 is prevented from moving in one direction.

The cylinder arrangement 82 delimits an annular cylinder 88 in which an annular piston is located 89 is located. The piston 89 serves to keep the clutch disks 85 in frictional engagement with the clutch disks 81 to bring the gear 78 to the intermediate shaft 39 to couple. To operate the Piston 89 is used to selectively let pressure fluid into the cylinder 88. To produce a Connection between the cylinder 88 and a pressure fluid source are used in the cylinder

arrangement formed liquid channel 90, a liquid channel 91 which is provided in the intermediate shaft 39 , a liquid channel 92 in a liquid distributor piece 93 which is inserted into the rear end wall of the gear housing 34 , and a liquid channel 94 formed in the gear housing cover 37. By means of screws 101 is on a cover plate 100 is attached to the cover part 37 and the gear housing 34. The oil for cooling the clutch plate 81 and 85 is fed through an opening 102 provided in the cover plate 100; From this opening the oil passes through a fluid channel 97 in the intermediate shaft 39 and through radial openings 98 in the hub section 79 of the gear wheel 78 and in the associated bushing 39 ' to the clutch plates.

On the intermediate shaft 39 , a gear 95 is fastened between the ball bearing 77 and the cylinder arrangement 82 and is constantly in engagement with the already mentioned gear 66 fastened on the intermediate shaft 38.

The transmission described above works as follows: When the output shaft 68 is to be driven in the forward direction, the gearwheel 42 is coupled to the intermediate shaft 38 by actuation of the coupling means 32. Then the drive between the input shaft 13 and the output shaft 68 takes place via the gearwheel 36, the gearwheel 42, the coupling means 32, the intermediate shaft 38, the gearwheel 66 and the gearwheel 67. If the output shaft 68 is to be driven in the reverse direction, the gearwheel is 42 is uncoupled from the intermediate shaft 38 , and the gear wheel 78 is coupled to the intermediate shaft 39, that is, while the coupling means 32 are put out of operation, the coupling means 72 are actuated at the same time. The gearwheel 36, the gearwheel 78, the coupling means 72, the intermediate shaft 39, the gearwheel 95, the gearwheel 66 and the gearwheel 67 now serve to mediate the drive between the input shaft 13 and the output shaft 68.

It can be seen that the gear 66 on the intermediate shaft 38 serves as a drive gear when the output shaft 68 is driven in the forward direction and as an intermediate gear when the output shaft 68 is driven in the reverse direction. By using the gear 66 as an intermediate gear, it is possible to dispense with the installation of an intermediate gear of relatively small diameter, which would necessarily have to operate at undesirably high speeds. Those skilled in the art will readily recognize that the torque multiplication between the motor and the output shaft 68 occurs through the torque converter 6 in both forward and reverse drive.

The housing 104 of a manual transmission is fastened to the rear end of the transmission housing 34 by means of screws 103. Within the gearbox housing 104. A drive shaft 105 is disposed whose front end is mounted in a built in the front end wall of the housing 104, ball bearings 106, while the rear end makes this shaft in a ball bearing 107 which is installed in the rear end wall of the housing 104 . At the front end of the drive shaft 105 , an internal gear 108 is fastened in a suitable manner, which is constantly in mesh with a gear 109 formed at the rear end of the transmission output shaft 68 . A gear 110, which is preferably made in one piece with the drive shaft 105 , is located near the front end wall of the housing 104; Furthermore, two axially spaced gears 111 and 112 are mounted on the sockets 113 and 114, which are concentric with the shaft 105. Dog clutch teeth 115 and 116 are formed on these gears 111 and 112, respectively. The gears 111 and 112 can optionally be coupled to the shaft 105 by means of a coupling mechanism generally indicated by the reference number 117 and to be operated by hand. The coupling unit 117 comprises a hub part 118 which is attached to the shaft 105 and on the outside has a straight spline 119 on which an annular coupling collar 120 with a straight internal spline 21 can slide axially. When the clutch collar 120 is slid to the right, the internal splines 121 are engaged with the dog clutch teeth 116 of the gear 112 to couple it to the shaft 105. When the coupling collar part 120 is pushed to the left, the internal spline teeth 121 are brought into engagement with the claw coupling teeth 115 of the gear 111, in order to make it with the

to couple the shaft 105.

Inside the housing 104 , below the drive shaft 105, there is a driven shaft 122, the front end of which is supported in a ball bearing 123 fastened in the front end wall of the housing 104 , while its rear end is supported in a ball bearing 124 fastened in the rear end wall of the housing 104 is. At the front end of the shaft 122 , in the vicinity of the ball bearing 123, a gear 125 is mounted on a bushing 126 arranged concentrically with the shaft 122 . The gear 125 is in constant mesh with the gear 110 on the shaft 105. Immediately behind the gear 125 on the shaft 122 is a clutch mechanism, generally identified by the reference numeral 127. The coupling mechanism 127 comprises a hub part 128 which is fastened on the shaft 122 and has external splines 129 which serve to receive the straight internal splines 130 of a coupling collar part 131 . The clutch collar 131 can be slid to the left to engage the internal splines 130 with the dog clutch teeth 132 formed on the gear 125 so as to couple the gear 125 to the driven shaft 122. Gears 133 and 134 are attached to driven shaft 122 and mesh with gears 111 and 112 on shaft 105, respectively.

The driven shaft 122 protrudes from the housing 104 , and a brake drum 135 is attached to its rear end, which can cooperate with a brake band 136 in order to brake the driven shaft 122.

For low speed, high gear ratio drive, the clutch collar 131 is moved to the left to couple the gear 125 to the driven shaft 122. • a drive for medium-speed and medium-speed ratio of the clutch collar 131 is in the in Fig: IC moved back position shown, and the clutch collar 120 is moved to the right to the gear 112 to be coupled to the drive shaft 105th For a drive with high speed and low gear ratio, the coupling collar 120 is moved to the left in order to couple the gear 111 with the drive shaft 105. From this

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it follows that by selectively actuating the from the position shown in Fig. 8 to the right be-coupling collar 120 and 131 between the drive is vycgt, the connection between the liquid shaft 105 and the. driven shaft 122 in. Each capacity opening 143 and the liquid channel 142 down-direction three .speeds or speeds break ,. .

The coupling collars 120 and 131 8 Tu of the valve opening 141 is a piston slide 159 can be optionally moved by means of suitable shift forks and linkage, which has a central annular groove 160. Since the latter has the latter -Means are designed in a known manner and not attached to cable 161, which can be connected to a control lever (does not form part of the invention, it does not appear shown) in a suitable manner, required to represent them in detail and to io to a movement of the The following are structural details and positions which are inevitably determined by the fluid control device according to the invention, generally indicated at 162 at 162, of the operation of an embodiment of the position determining means. 8 position of the shooting record shown n ;. This device enables the actuation 15 above 159, fluid flowing through the channel 142 in the fluid-operated couplings 32 and 72 and the opening 141 can only flow around the piston valve the supply of 'fluid under a pressure, ie within the annular groove within a suitable area to the liquid 160, It should be noted that the liquid orifices keitsdrehmomentwandler 6, 153 and 154 in that the valve body 138 is arranged inside the control device according to the invention comprises 120 half of the housing 104, with the internal control valve mechanism, the 4 to 8 Ren of serving as a sump container housing 104 is shown in detail. Who stand through the reference connection. If now the piston slide number 137 generally marked control valve from the position shown in Fig. 1 moves to the left mechanism comprises a valve body or a, the: liquid channel 142 through the ring housing 138, the 25-shaped groove within the gearbox housing 160 is arranged with the liquid opening 153 in 104 and connected to this by means of the flange. The opening 154 remains in Ver-139 can be attached. In the valve body 138 there is a connection with the interior of the housing 104. If two parallel valve openings 140 and 141 are now the piston slide 159 shown in FIG. These openings 140 and 141 are moved through ... th position to the right, the channel • a liquid channel 142 is connected to one another. 30 142 is connected to the opening 154, while the öff-Further, a fluid opening 153 is provided in the valve body 138 again with the interior of the housing 104 opening 143, one end of which is connected to the outside. · ..

opens, while the other end with the valve Fig. 9 shows schematically the liquid circuit opening 140 and a liquid channel 144, which is in the control device according to the invention. Which extends parallel to the openings 140 and 141, the liquid opening 143 already mentioned in FIG. 35, in which there is a valve connection. A non-return valve, generally identified by the reference numeral 145 with the delivery side of a liquid pump 20, can be installed in the liquid channel 144 through a line (not shown), which check valve can be connected to one. Thus, the opening 140 can be in the relatively high pressure, for example in the size valve body. 138, at 163 a schematic representation of about 6.3 kg / cm ² is set. The 40 provided fluid channel means pressurized fluid to check valve 145 comprises a ball 146 and a guide. The control openings 153 and 154 spring 147. Behind the valve ball 146 there is a suitable line (not shown) with a liquid channel 144 with an opening 148 in the cable provided in the gear housing cover 37, which opens outside the valve body 138. Channels 65 and 94 are connected. "The in Fig. 9 schematic-further behind the valve ball 146 an opening 141 represented by the 45 table is thus arranged through the non-return valve 164 and 165 indicated generally at reference numeral 149, respectively. which is connected to a medium pressure in with the coupling means 32 and 72. The ^{pump 20 set of the order of magnitude of about 2.8 kg / cm 2} is also-by, which is in Fig. 9 at 166. The check valve 149 comprises a ball 150 ... indicated liquid channel means to the sump and a spring 151 and is connected to a liquid channel 50 container or the housing 104 In the position shown in FIG. 9 , the piston opens into the housing 104 ... slides 155 and 159 are the coupling means 32 and

Two axially spaced liquid 72 connected to the sump container 104 and located Openings 153 and 154 each have one end ... therefore out of service .. If the coupling with the valve opening 141 in connection, while 55 means 32 are to be actuated, the actuation becomes theirs other ends outside the valve body 138 wire 161 from the position shown in Fig. 9 after flow out. pressed to the left, whereby the slide 159 is pushed to the left. Inside the opening 140 there is a piston. the channel 142 with the to the slide valve 155, the slide of which has a central ring coupling means 32 leading fluid channel-shaped Has groove 156. To connect within the piston 60 means 164. It can be seen that the A suitable Bowden wire 157 is attached to the slide, coupling means 72 in this position of the slide which suitably with a control lever (not 159 remain ineffective as they are represented over the liquid) can be connected so that the piston channel means 165 with the sump container 104 in slide 155 within the opening 140 there is an optional binding. If the coupling means 72 can be moved. The valve 155 has two 65 to be actuated, the slide 159 is out of the Positions that are shifted to the right by the position shown generally at 158 in FIG Teten position determining means inevitably determined whereby the liquid channel means 165 with the are. In the position shown in FIG. 8, channel 142 connects. At the same time, the the valve 155 the fluid opening 143 with the fluid-fluid channel leading to the coupling means 32 142. When the valve piston 155 70 connects channel means 164 with the sump tank 104

bound, whereby the coupling means 32 are put out of operation. From the above description it can be seen that either the coupling means 32 or the coupling means 72 can be actuated or both coupling means can be put out of operation by selectively moving the piston slide 159.

When the forward clutch 32 or the reverse clutch 72 is actuated, a drive is imparted between the input shaft 13 and the output shaft 68, whereby a driving force is applied to the drive shaft 105 of the transmission means arranged in the housing 104. When changing the gear ratios, it is necessary to relieve the drive force on the shaft 105 before moving the coupling collars 120 and 131. To do this quickly and forcibly, the plunger slide 155 may from be in Fig. Position illustrated 9 to the right moves to the connection between the fluid passage means 163 and to interrupt the channel 142 and the channel 142 to the sump 104 to be connected, whereby the respectively selected forward or Reverse clutch means 32 and 72 are put out of operation. As a result, the drive between the input shaft 13 and the output shaft 68 of the transmission is interrupted, and the drive shaft 105 of the transmission means is relieved of the drive force. After the desired transmission ratio has been selected within the change gear means, the control piston 155 can be moved back into the position shown in FIG. 9 in order to restore the connection between the fluid channel means 163 and the channel 142 .

The control device according to the invention also serves to control the flow of pressurized fluid to the torque converter 6. If the pressure of the pressurized fluid supplied to the opening 143 and the channel 144 (both formed in the valve block 138 ) exceeds a value of approximately 6.3 kg / cm ² , this will occur Check valve 145 is open, and pressure fluid flows through this valve into the fluid opening 148, which is connected by a line (not shown) to the channel 21 which is provided in the flange part 17 fastened to the rear end wall of the torque converter housing 7. As already explained in detail, the liquid entering the channel 21 is directed into the interior of the pump housing 8. The liquid flowing through the check valve 145 can thus reach the torque converter 6 through the liquid channel means 167 shown schematically in FIG. 9. As also explained above, liquid flows, which the turbine elements 11 leaves the torque converter 6 through which schematically illustrated at 168 fluid channel means to the check valve 26. As shown in Fig. 9 schematically illustrates the check valve 26 by flowing fluid through fluid conduit means 169 a condenser 170 from which the liquid passes through liquid channel means 171 into the sump tank 104 . Suitable fluid lines (not shown) connect the fluid channel means 171 to the above-mentioned fluid openings 56 and 102 which are formed in the end plates 57 and 100 attached to the gear housing 34 and to the cover part 37 '; from these openings the liquid reaches the groups of coupling plates 45 and 49 or 81 and 85 in order to cool them. As shown schematically in FIG. 9, liquid channel means 172 suitable for this purpose connect the liquid channel means 171 to the couplings 32 and 72.

In the event that the pressure of the fluid supplied to the torque converter 6 ^{exceeds the value of approximately 2.8 kg / cm 2} , it is provided that the fluid opens the check valve 149 so that part of the fluid flows through the opening 152 to the sump container 104 is diverted. From the above it can be seen that the three check valves 26, 145

ίο and 149 cooperate to maintain the pressure of the fluid flowing to the torque converter 6 within the proper range for high efficiency operation of the torque converter.

The presently described in detail transmission proves to be particularly useful in a lifting vehicle with which loads are grasped, transported and set down. When the lifting vehicle raises or lowers loads, the engine used to drive the Kurbeiao shaft 4 must be operated to drive the fluid pump which is used to develop the fluid pressure for actuating the various auxiliary devices of the vehicle. It is also often necessary to move the vehicle forward or backward centimeters when gripping and lifting or lowering a load in order to bring it into the correct position. In order to enable the last-mentioned operations to be carried out correctly, in a modified embodiment of the control device according to the invention, means are provided for deactivating the clutches 32 and 72 when the brakes of the vehicle are applied. The engine can thus remain in constant operation while a load is being raised or lowered, while at the same time the drive between the input shaft and the output shaft of the transmission can be quickly and forcibly interrupted and switched on again in order to enable the vehicle to move centimeter by inch without the To interfere with operations of lifting or lowering a load.

In the modified embodiment of the invention, the control valve mechanism, generally designated by the reference numeral 173 in FIG. 10, is used which, like the valve mechanism 137 described above, is arranged within the transmission housing 104 and fastened in a suitable manner to the side wall thereof. The control valve mechanism 173 comprises a valve body 174 in which two parallel valve openings 175 and 176 are provided. These openings are connected to one another by a liquid channel 177. Furthermore, a channel 178 is formed in the valve body 174 , one end of which is connected to the valve opening 176 , while the other end opens outside the valve body 174. In addition, two channels 179 and 180 are provided in the valve body 174 , one end of each of which is connected to the valve opening 175 , while the other ends open outside the valve body 174. In the valve opening 175 there is a piston slide 181 with a central annular groove 182. One end of the slide 181 is connected by means of a bracket 183 to a crank arm 184 which cooperates with an actuating lever 185 ; this operating lever can be brought into three different positions in order to move the slide 181 into three different positions.

A piston slide 186 with a first annular groove 187 is located in the valve opening 176.

At one end of the valve opening 176 a holding cup 188 is provided which carries a helical spring 189 supported against one end of the slide 186. A second annular groove 190 is formed on the piston slide 186 and communicates via a radial opening 191 with an axial fluid channel 192 which, as shown in FIG. 10, opens out at the left end of the valve outside the same. Pressure fluid that reaches the annular groove 187 within the opening 176 through the channel 178 and seeps through the outer circumference of the slide 186 collects in the annular groove 190 and is guided back through the opening 191 and the channel 192 into the sump container 104.

At the right end of the slide 186 is a generally cup-shaped disk 193 which is normally supported against a closure part 194 fastened in the right end of the valve opening 176. A liquid channel 195 is provided in the valve body 174 , one end of which is connected to the valve opening 176 between the closure part 194 and the cup-shaped cuff 193 , while the other end of the channel 195 opens outside the λ ^ εηίϊΐ-body 174.

The liquid channel 178 is connected to the delivery side of the liquid pump 20 by a line (not shown). The valve opening 176 is thus in communication with the pump 20 by fluid channel means which are shown schematically in FIG. 11 at 196. The channels 179 and 180 are connected to the openings 65 and 94 provided in the gear cover part 37 by lines not shown. Thus, the valve opening 175 is in communication with the couplings 32 and 72 through the fluid channel means shown schematically in FIG. 11 at 197 and 198.

The slide valve 181 works essentially in the same way λνίε the valve 159 described above in connection with the first embodiment of the control device according to the invention. In other words, when the slide 181 is moved to the left from the position shown in FIG Communication established between the fluid channel means 197 and the channel 177 so that pressurized fluid can flow to the clutch 32 to actuate it. In this position of the slide 181 , the coupling 72 is connected to the sump container 104 via the liquid channel means 198 . However, when the slide 181 is moved to the right from the position shown in FIG. 11, the coupling 32 is connected to the sump container 104 by the liquid channel means 197 . If the slide 181 is pushed all the way to the right, the coupling 72 is connected to the pressure fluid source by the fluid channel means 198 and is thus actuated. It can be seen that the slide 181 can assume one of three positions, ie a neutral position or a position in which either the clutch 32 or the clutch 72 is actuated.

The already mentioned fluid line 195 is connected to the master cylinder 197a of the vehicle's braking system via a line 196a. In the master cylinder 197a there is a piston 198a which can be moved by the brake pedal 200 via a suitable linkage (indicated schematically at 199). When the brake pedal 200 is depressed, the fluid in the master cylinder 197a is pressurized and thus exerts a force on the fluid in the lines 201 and 202 , which lead to the wheel brake cylinders indicated schematically at 203 and 204. When the wheel brake cylinders 203 and 204 are actuated to apply the brakes of the vehicle, a force is also exerted on the fluid in the lines 195 and 196 α , which in turn exerts a force on the cup-shaped sleeve 193 within the valve opening 176 in order to prevent the To push the slide piston 186 according to FIG. 10 to the left against the force of the spring 189. If the slide 186 is moved to the left, the connection between the channel 177 and the channel 178 is interrupted, while the channel 177 is connected to the sump container 104 through an opening 205, whereby the previously actuated clutch 32 or 72 is relieved of the fluid pressure and is thus put out of operation.

Upon release of the brake pedal 200, the pressure on the liquid in the master cylinder 197a is depressurized, whereby the lines 195 and 196 a and the valve opening 176 are depressurized. Then causes the spring 189 that the slider 186 returns to the right in Fig. 10 position shown, the connection between the opening 205 and the channel 177 and to interrupt the connection between the channels 177 and 178 restore.

From the above description it can be seen that the actuation of the clutches 32 and 72 for. Centimeter-wise movement of the vehicle can be controlled by appropriate manipulation of the brake pedal 200.

In the modified embodiment of the control device according to the invention, the fluid flowing to the torque converter 6 is also controlled by check valves. A check valve 207 (FIG. 11), which is set to a relatively high pressure on the order of about 6.3 kg / cm ² , is in communication by liquid channel means 208 with the liquid channel means 196 connected to the delivery side of the pump 20. The check valve 207 is also connected to the torque converter 6 by fluid passage means 209. The fluid flowing through the torque converter 6 is returned through fluid passage means 210 and a check valve 211 set at a relatively low pressure on the order of about 1.4 kg / cm ² to fluid passage means 212 connected to the sump tank 104. The check valve 213, which is set to a mean pressure of the order of magnitude of 2.8 kg / cm ² , is connected between the check valve 207 and the torque converter 6 through the line 214 to the aforementioned line 209 . The check valve 213 is also in communication through line 215 with a cooler 216 , from which the liquid is conducted through line 217 to the sump tank 104 and to the clutch plates of the clutches 32 and 72 in order to cool the clutch plates.

It can be seen that the aforementioned check valves 207, 211 and 213 cooperate with each other in such a way that the pressure of the fluid flowing to the torque converter 6 is kept within the correct range for the operation of the torque converter with high efficiency.

Claims (5)

PATENT CLAIM: 1. Transmission with hydraulic control device for driving lifting vehicles with a hy- Hydraulic torque converter, with intermediate shafts for reversing the direction of rotation and with several gear ratios to be switched by means of claw clutches in a combination of elements known per se, characterized in that on each of the two intermediate shafts (38 and 39) a hydraulically operated multi-plate clutch (32 and 72) for the optional connection of one of these Intermediate shafts are arranged with the transmission input shaft (13) and a first and a second control valve are located in a hydraulic fluid circuit fed by a pressure source, whereby the first control valve (159) optionally pressurizes one or the other clutch with hydraulic fluid and thereby actuates it can and through the second. Control valve (155) the connection line between the first control valve (159) and the second control valve (155) can optionally be connected to the pressure source or the sump, whereby a decoupling takes place. 2. Transmission with hydraulic control device according to claim 1, characterized in that the second control valve (186) has a hydraulic actuating device which is connected to a hydraulic brake system of the lifting vehicle in such a way that when the brakes are actuated at the same time an automatic release of the respectively in use position Coupling takes place and when the brakes are released, this coupling is automatically brought back into the use position. 3. Transmission with hydraulic control device according to claim 1, characterized in that the second control valve (155) can be operated by hand. 4. Transmission with hydraulic control device according to claim 1 to 3, characterized in that a third position is additionally provided for the first control valve (159 or 181) in which the pressure fluid lines (165, 165 ) leading to the two clutches (32, 72) 164 or 197, 198) are in connection with the sump. 5. Transmission with hydraulic control device according to claim 1 to 4, characterized in that the pump (20) required for the return of the liquid in the torque converter (6) simultaneously serves as a pressure source for the control device and in the line (144) leading to the torque converter a first check valve (145) is provided, which is set to a pressure which is higher than that for a favorable efficiency of the torque converter and sufficient for the actuation of the clutches (32, 72) , behind the first check valve a return line bypassing the torque converter ( 152) branches off with a second check valve (149) , which limits the fluid pressure in the line to the torque converter upwards, and a third check valve (26) is provided in the return line (168) between the torque converter and the sump (104), which controls the fluid pressure in the line to the torque converter limited downwards, the second and d ritte check valve are adjusted to maintain fluid pressure in the range required for optimal torque converter operation. Considered publications:
U.S. Patent Nos. 2,419,059, 2,461,116, 511,039, 2,530,720, 2,598,865. In addition 4 sheets of drawings © 809 768/322 2.59