SU1344986A1 - Jaw safety clucth - Google Patents

Abstract

The invention relates to the field of mechanical engineering and can be used in all sectors of the national economy to protect high-speed machines and mechanisms from overloads. The aim of the invention is to increase the durability by automatically adjusting the pressing force of the coupling halves (P) to dependent f (L 8 00 4 4 from 00 USf

Description

ti from transmitted torque. The coupling contains a driver P 1 installed on screw slots with the possibility of axial movement on sleeve 2, and driven P 3 mounted on sleeve 2 by means of sliding bearing 4, П are interconnected by cams 5. The angle of slope of the splines to the axis of the coupling is made smaller angle of the profile of the cams P 1 and 3. An annular groove 6 is formed on the inner surface of the P 1, and on the outer surface of the sleeve 2 is made on

The invention relates to mechanical engineering and can be used in all sectors of the national economy to protect high-speed machines and mechanisms from overload.

The aim of the invention is to increase durability by automatically adjusting the force of pressing the coupling half depending on the transmitted torque.

Fig 1 shows the proposed coupling, a longitudinal section; in fig. 2, section A-A in FIG. Ij in FIG. 3 shows a section BB in FIG. 1 | figure 4 - the mutual position of the goods and the leading coupling half at the intermediate stage of the open; in fig. 5 - relative position of the half-coupling cams at the intermediate stage of opening; .on FIG. 6 - the mutual position of the goods and the leading coupling half when the coupling is fully opened; in fig. 7 - relative position of the cams of the coupling half at full opening of the coupling; in fig. 8 is a diagram of the forces acting on the lead coupling half when transmitting torque.

The safety cam clutch contains a leading coupling half 1, mounted on screw slots with the possibility of axial movement on sleeve 2, and a driven half body 3, mounted on sleeve 2 by means of a sliding bearing 4. Sleeve 2 can be performed as a whole, and that team. On the face-surfaces of the half couplings 1 and 3 facing one another, the cams 5 are made.

44986

 right is the grooves 13, in which centrifugal weights 14 are stapled in shape with the ability to interact with the annular groove 6. The torque from sleeve 2 is through the slits and is transmitted to P 1 and through the cams 5 to P 3, and the centrifugal The weights 14 are pressed against the inner surface of the P-1. As the torque changes, the axial force changes, acting thinly in the spline connection of P 1 and sleeve 2 and the pressing P 1 to P 3. 8 Il.

five

five

0

five

2

made on the leading coupling half 1 and the sleeve 2, in the cross section normal to the helix, can have rectangular, trapezoidal or involute profiles, and the direction of the helix of the slot is chosen so that the axial force arising in the splined connection presses the leading coupling half 1 to the driven coupling half 3 The slope angle of the splines to the coupling axis is made smaller than the cam profile angle of coupling half 1 and 3. An annular groove 6 is trapezoidal in cross-section in the inner surface of the leading coupling half 1. The driven coupling half 3 is rigidly connected to the sprocket 7 of the chain coupling of the chain drive or another element connecting the coupling with the working parts, and fixed from axial displacement along the hub 2 by the retaining ring 8. The half coupling 1 and 3 are fitted with one another relative to the other central A spring 9 or a set of springs located between the washers 10 and 11. Press the coupling half, and, conversely, the magnitude of the transmitted torque is adjusted by nuts 12. In the guide grooves 13, made on the outer surface of the sleeve 2, va skoboobraznyh centrifugal load 14 (Fig. 1,3) having at the end face on the side opposite the cams drive coupling part 1, a tapered surface .. Loads 14 may be podprulsineny to the inner surface of a leading half of the coupling 1 pru- zkinami 15. Loads 14 are located on

sleeve 2 so that when the clutch is closed, the distance between the tops of the tapered surfaces of the weights 14 and the annular groove 6 on the inner surface of the leading coupling half 1 is less than the height of the cam. The weights are secured against turning on the sleeve 2 with the help of the bald patches made on it. The clutch is closed by a casing 16 connected to a driven coupling half 3 by a cap nut 17. The clutch is sealed by a ring 18 and cuffs 19 and 20.

Cam clutch operates as follows.

The clutch is pre-set to transfer the required torque, for which change the force of pressing the leading coupling half 1 to the driven half coupling 3, compressing the spring 9 with nuts 12. The required force of the spring 9 is determined from the dependence

 tg (-f) - j-tg- (7 + F,) - 25

D

- (F, + p np) -f,

20

D

(/ f

d

P.

-np

f H;

14

where T is the torque transmitted by the clutch, Nm; outer diameter of the cams, m; cam profile angle, hail; friction angle on cam surfaces, hell; average diameter of the splines, m; tilt angle of the splines to the axis of the coupling, deg;

friction angle in spline joint, hail;

centrifugal force of the cargo, the total force of the springs 15, unclenching cargo 14, N; the coefficient of friction of loads on the leading half coupling 1. The torque from sleeve 2 through the splines is transmitted to the leading coupling half 1, and from it through the cams 5 to the driven coupling half 3 rigidly connected with an asterisk 7 or another element connecting the coupling with the working bodies. Here, the centrifugal weights 14 are pressed against the inner surface of the leading half-coupling 1.

When the moment of resistance changes, the axial force acting in the splined joint of the drive coupling half 1 and the sleeve 2 and pulling the driving coupling half 1 to the driven coupling half changes. Thus, as the torque increases

resistance on driven half coupling 3, this force also increases, but since the cam profile angle is greater than the slope of the spline helix, the repulsive force of coupling halves 1 and 3 increases as the resistance moment increases faster. At the moment when the repulsive force of the coupling halves 1 and 3 will balance the axial force acting in the spline connection of the leading coupling half 1 and the hub 2, and the force of the springs 9, the coupling will open, i.e. leading half coupling 1 moving

the slots of the sleeve 2, will be released from engagement with the driven coupling half 3.

At the final stage of the cam coming out of engagement into contact with the tapered surface of the annular groove

on the inner surface of the leading half coupling 1 there enters the conical surface of the weights 14 (figs. 4 and 5), which are emitted under the action of centrifugal forces and the bows of the springs 15 along the flats on the sleeve 2 in the radial direction. The resulting axial forces, compressing the spring 9, withdrawing the cams of the coupling half from the engagement, and withdraw the driving coupling half 1 from the driven coupling half 3 to a predetermined distance. The transmission of torque to the driven coupling half 3 is stopped. The leading coupling half 1 is held in the open position with weights 14 until rotation is transmitted to sleeve 2 (Fig. 6.7). At the same time it is necessary to fulfill the conditions

Рц + Р пр 7 РПР (tgB + fnpHB),

40

45

50

55

where B is the angle of inclination of the loads forming the cones 14 and the annular groove 6 on the leading coupling half 1 to the base, degrees;

f - reduced coefficient.

Neither the load 14 is about the sleeve 2. and the leading half coupling 1. When the rotation of the sleeve 2 is turned off, the centrifugal forces of the loads 14 decrease from the maximum value to zero. When determining the value of the rotational speed, the leading half-coupling 1, by acting with the conical surface of the annular groove on the conical surface of the weights 14, begins to move them to their original position. When the goods out of the ring groove 14, the coupling closes. For

coupling closure is necessary

pr P, p (tgB-f, p, 3).

Spring-loaded cargo 14 to the inner surface of the master coupling half 1, you can achieve the beginning of the coupling closure at the minimum speed of rotation of the sleeve 2.

At the moment of launch, when large accelerations in the spline joint act, an additional inertia force arises, pressing the leading coupling half 1 to the driven coupling half 3, which allows the coupling, when it is set to transfer the nominal torque, to transfer, without opening, the starting loads.

When braking the drive coupling half 1, when negative accelerations act, this inertia force contributes to the opening of the coupling.

Installing the drive half coupling on the screw slots reduces the axial dimensions of the coupling by reducing the size of the spring compressing the coupling half and its radial dimensions, because the centrifugal force of the loads, which depends on their size, decreases to keep the driving coupling half in the open position.

ditch In addition, it provides automatic regulation of the force of pressing the coupling half, depending on the torque transmitted by the clutch. Due to a reduction in the required force of the spring compressing the coupling halves, the shock of the coupling halves is reduced when closing, which leads to an increase in the life of the coupling.

Claims (1)

Invention Formula The cam clutch contains two leading and driven coupling halves, coupled by end cams, a sleeve with guide grooves on the outer surface and a fixing mechanism of the leading coupling half in the open position in the form of stapled loads installed in the guide grooves of the sleeve with the ability to interact with the ring groove on the leading half coupling, which is connected to the sleeve by means of slots, characterized in that, in order to increase durability due to automatic Ani depending on the transmitted torque, the forces of the coupling half, the splines are screwed with a tilt angle to the coupling axis less than the cam profile angle, Fig 2 /four FIG. four dzie.5 fi & .b fiv.7 Compiled by T. Yanova Editor A. Makowska Tehred M. Didyk Corrector I. Muska Order 4904/37 Circulation 804Subscription VNIIPI USSR State Committee for inventions and discoveries 113035, Moscow, Zh-35, Raushsk nab., 4/5 Production and printing company, Uzhgorod, st. Project, 4 FCh9-8