RU2251632C1 - Force - cooled friction clutch - Google Patents

Abstract

FIELD: mechanical engineering.

SUBSTANCE: invention relates to devices for transmission of rotation and it can be used in tractors, automobiles, materials handling equipment and other devices used to control rotating high-inertia masses. Proposed force-cooled friction clutch contains inner and outer clutch members with channels for lubricating and cooling liquid, friction disks with grooves and holes inter connecting all spaces of grooves and engagement mechanism made in form of cylinder with pressure ring-shaped piston provided with channels and spring-loaded spools for forced lubrication of friction disks. Novelty is that through holes are made in radial direction in pressure ring-shaped piston. Stop is made in each hole from side of inner diameter of piston. Plug is fitted in each hole from side of outer diameter of piston. Spools are solid parts with ring-shaped grooves, and two channels for lubricating-and-cooling liquid are made in piston for each spool. One channel is connected with grooves and holes of friction disks, and the other is connected with space formed between plug and upper end face of spool.

EFFECT: improved efficiency of disk cooling without decrease of transmission of torque and prevention of liquid friction between disks with clutch disengaged.

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Description

The invention relates to the field of engineering, in particular to devices for transmitting rotation, and can be used in tractors, automobiles, hoisting mechanisms and in other devices associated with the control of rotating high inertia masses.

A known design of a friction clutch operating in oil, which has an inner half coupling and an outer half coupling with channels for lubricating coolant (hereinafter referred to as the coolant), friction discs in which annular grooves and holes are made connecting all cavities of these grooves to each other, the switching mechanism, made in the form of a cylinder with a pressure annular piston. In the piston, channels are made into which throttles with calibrated holes are inserted [1].

The disadvantages of this design are the inability to supply coolant without reducing the transmitted moment and the inability to accurately control the amount of coolant supplied to the friction surfaces.

The closest in technical essence is a friction clutch containing an internal half-coupling and an external half-coupling with coolant channels, friction discs, a switching mechanism made in the form of a cylinder with a pressure annular piston, in which spring-loaded hollow spools with holes made with the possibility of connecting them to the cavity in which the friction discs are located [2].

Coolant is supplied to friction surfaces of friction discs in two ways. One coolant stream is supplied from the oil bath formed in the inner coupling half, under the action of centrifugal force on the coolant through a calibrated hole. The second coolant flow is supplied only to the friction disk located at the annular piston due to the overflow of fluid from the oil bath in the inner coupling half. In this case, part of the coolant supplied through the spool is poured into the crankcase, where the friction clutch is located, and, therefore, is not involved in the removal of heat.

The disadvantages of this design are the inability to accurately control the amount of coolant supplied to the friction surfaces, and the overspending of the coolant supplied to the friction clutch, as well as the dependence of the amount of coolant involved in the heat removal on the angular speed of rotation of the friction clutch.

The objectives of the invention are the creation of a friction clutch with forced cooling, which provides more efficient cooling of the disks without reducing the transmitted torque, and the elimination of harmful fluid friction between the disks in the off friction clutch.

The essence of the invention lies in the fact that the friction clutch with forced cooling contains internal and external half-couplings with channels for lubricating coolant, friction disks with grooves and holes connecting all cavities of the grooves to each other, the switching mechanism, made in the form of a cylinder with a pressure ring piston having channels and spring-loaded spools of forced lubrication of friction discs.

The difference between the proposed friction clutch and the known one is that through holes are made in the radial direction of the pressure annular piston, and a stop is made in each bore of the piston’s inner diameter, and a plug is installed in each bore of the piston’s outer diameter, and spools made of an integral design with annular grooves, and in the piston for each spool there are two channels for lubricating-cooling fluid, one of which is connected to the grooves and a hole iyami friction discs and the other - with a cavity formed between the cap and the upper end of the spool.

This difference provides an increase in the cooling efficiency of the friction surfaces of the friction clutch due to the forced supply of the required amount of coolant under pressure on the friction surface directly from the cylinder cavity. In addition, when the clutch is turned off or in the clutch is turned on (without slipping), the spool located in the piston and controlled by pressure in the cylinder cavity allows completely eliminating or arbitrarily reducing the amount of coolant supplied to the disks. At the same time, idling eliminates fluid friction and harmful braking torque in the transmission, and when the clutch is turned on, the appearance of a squeezing force in the disk pack is eliminated, which increases the compression of the disks and makes the transmission of torque more reliable.

Figure 1 shows a General view of the friction clutch. Figure 2 shows the friction clutch during the inclusion process. In FIG. 3 shows the position of all parts of the coupling in the fully engaged state. 4 and 5 show, respectively, the slave and the leading friction discs.

The friction clutch is rigidly mounted on the shaft 1 and has an outer 2 and an inner 3 coupling halves. In the outer coupling half 2, a push-ring annular piston 4 is installed, which is pressed by the springs 5 from the thrust washer 6, leading friction discs 7 located between the annular piston 4 and the supporting disc 8. The driven discs 10 are located on the inner coupling half 3 mounted on the bearings 9. For Channels 12 and 13 are provided for supplying oil to the cavity of the cylinder 11 in the shaft 1 and in the outer coupling half 2, respectively. The cavity of the cylinder 11 is sealed with rings 14 and 15 to prevent oil leakage. To ensure forced cooling of the friction discs 7 and 10 by pressing This annular piston 4 is provided with a passage 16 and a control channel 17 and a spool 18 of forced lubrication, which is fixed on the outer diameter of the pressure annular piston 4 with a plug 24, and on the inner diameter it is pressed by a spring 19 resting on a stop 23. On the same radius as the passage channel 16 in the friction discs 7 and 10 is made grooves 20 and holes 21 (see figure 4 and 5), which when compressed, the friction discs 7 and 10 form a through flow system 22. In more detail, the location of the grooves 20 and holes 21 ve home friction disk 10 is shown in figure 4, and the leading friction disk 7 in figure 5.

The friction clutch with forced cooling operates as follows. The external source delivers oil at the command of the control (the external source and the control device are not shown) under pressure through channels 12 and 13 into the cylinder bore 11. As the pressure in the cylinder bore 11 increases, the annular piston 4 overcomes the pressing force of the springs 5 and compresses the set of friction discs 7 and 10. This starts the transmission of torque. The process of turning on the coupling is accompanied by slipping and heat generation and lasts until the rotation speeds of the leading 7 and 10 driven friction discs are completely equalized. Simultaneously with the movement of the annular piston 4, increasing pressure in the cavity of the cylinder 11 along the control channel 17 begins to act on the spool 18, which compresses the spring 19. With this movement, the groove of the spool 25 is gradually aligned with the passage channel 16, thereby opening the coolant to the friction discs 7 and 10. Next, the oil through the flow-through system 22 in the friction discs 7 and 10 lubricates the friction surfaces, while cooling the friction discs 7 and 10, and flows into the case of the friction clutch.

When the clutch is in the fully engaged state, the oil pressure in the cavity of the cylinder 11 has reached its maximum operating value, slipping is completed, the spool 18 completely compresses the spring 19 under the action of pressure and again closes (or limits to the required value) the coolant passage through passage 16 to the friction disks 7 and 10. Cutting off the coolant (or significantly reducing it) is aimed at increasing the compressive force of the friction disks 7 and 10 by eliminating the expanding force between these disks and providing the necessary margin friction torque at rotation transmission clutch.

When the clutch is turned off, the parts work in exactly the opposite order. In the off position, the pressure annular piston 4 is pressed. Friction discs 7 and 10 are free. The spool 18 is pressed by the spring 19 to the stop, thereby blocking the coolant from the cylinder 11 cavity to the friction discs 7 and 10 through the passage channel 16, which avoids the occurrence of harmful fluid friction between the disks at idle.

Thus, the original design of the spool and channel system incorporated in the invention allows to obtain the necessary increase in the amount of coolant on the friction surface of the disks by forcing it directly from the cylinder cavity during the on / off process when slipping the coupling. At idle, liquid friction and harmful braking torque in the transmission are excluded, and when the clutch is engaged, a significant reduction in the amount of coolant in the channels on the friction surfaces increases disk compression and makes torque transmission more reliable.

Sources of information

1. Description of the invention to patent US 5495927 A, cl. F 16 D 13/72, 1996.

2. Description of the invention to the copyright certificate SU 1180578 A, cl. F 16 D 13/72, 1985.

Claims (1)

Friction clutch with forced cooling, containing internal and external coupling halves with channels for lubricating coolant, friction disks with grooves and holes connecting all cavities of the grooves to each other, a switching mechanism made in the form of a cylinder with a pressure annular piston having channels and spring-loaded spools forced lubrication of the friction discs, characterized in that through holes are made in the radial pressure push-ring piston, while on the inside the piston diameter in each hole is emphasized, and a plug is installed in each hole on the outer diameter of the piston, the spools are made of an integral design with annular grooves, and two channels for lubricating-cooling fluid are made in the piston for each spool, one of which connected to the grooves and holes of the friction discs, and the other with a cavity formed between the plug and the upper end of the spool.

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