WO2004106764A1

WO2004106764A1 - Mechanical soft-actuated coupling

Info

Publication number: WO2004106764A1
Application number: PCT/CN2004/000552
Authority: WO
Inventors: Zhongyuan Hong; Hua Hong; Xia Hong
Original assignee: Zhongyuan Hong; Hua Hong; Xia Hong
Priority date: 2003-05-29
Filing date: 2004-05-27
Publication date: 2004-12-09
Also published as: CN1553062A; CN1260488C

Abstract

The present invention relates to a flexible mechanical soft-actuated coupling. It mainly comprises a spider provided with blades and connected with a spindle of a motor, a friction casing provided outside the spider and connected with the left and right caps, and centrifugal steel balls between the spider and the casing. A lot of dampers are provided on the spider shaft between the spider blades. A conical bore is provided in the spider shaft, a conical sleeve is provided in and matching with the conical bore. An opening is on one side of the conical sleeve, said conical sleeve with the keyway thereon is fitted on the spindle of a motor. Therefore, the advantages of the coupling are fair arrangement, good softactuated performance, wide applicability, mass production, stable and reliable transmission process, good transmission quality and convenience for assembly and disassembly and so on.

Description

Mechanical soft starter

Technical field

The present invention relates to a mechanical power transmission device, and in particular, to friction generated by a steel ball centrifugal body during rotation between a prime mover (motor, turbine, reciprocating engine, etc., hereinafter simply expressed by a motor) and a load Structural improvement of a mechanical soft starter using torque to transfer power.

Background technique

The applicant of this patent applied for a utility model and invention patent named "centrifugal moment-limiting steel ball coupling" in 2001 (patent number: 01209432.4, application number: 01108396.4, international application number: PCT / CN02 / 00160) . It mainly connects the star wheel with the main shaft of the motor and is the active part that transmits power; the load is connected with the half body, the left cover, the right cover, the friction shell, the gland, etc., and becomes the passive body of the steel ball coupling; The steel ball dispersion and red dan powder are mixed to form a transmission medium uniformly distributed in a fan-shaped cavity divided from the friction shell and the star wheel blades; a shaft stopper is arranged on the shaft body between the star wheel blades. During operation, the motor drives the star wheel and throws the transmission medium to the inner wall of the friction shell and the sides of the left and right covers to generate friction torque. When the resistance torque is greater than the load, drag the passive body to rotate to achieve power transmission; when it is less than the load resistance torque, the passive body cannot be dragged to achieve no-load soft start of the motor, or overload protection function, Or multi-machine drive coordination function. However, there are still the following disadvantages: 1. Due to the large range of the size of the spindle that involves the connection of the motor and the load, the model scale of its series spectrum reaches as many as hundreds of types, which can only be sold by order, single-piece production, and supply The long cycle and high cost make it impossible to organize large-scale production, and it does not meet the needs of domestic and foreign countries, especially restricting the development of international markets. 2. The structure length is longer than that of ordinary ordinary couplings, which brings difficulties and infeasible problems to customers' existing equipment technology innovation. 3. There are many links in the structure that make up the dimensional chain, and the accumulated error is large, resulting in a large coaxiality error between the installation alignment reference and the centerline of the motor spindle, and the transmission quality is reduced. 4. It is easy to damage the coupling or destroy the flexible connection when it is implemented by forced compression during installation and disassembly, resulting in the failure of the transmission function. Disclosure of invention

The invention overcomes the above-mentioned shortcomings of the prior art, and provides a mechanical soft starter with a reasonable structure, good versatility, suitable for large-scale production, and capable of meeting the immediate needs of the domestic and especially international markets.

The invention also solves the technical problems in the prior art, such as poor applicability and reliability, poor transmission quality, and inconvenient assembly and disassembly.

Confirm this The above-mentioned technical problems of the present invention are mainly solved by the following technical solutions: including a star wheel with blades connected to the main shaft of the prime mover, a friction shell provided outside and connected to the left and right covers, and a steel ball interposed therebetween The centrifugal body is provided with a plurality of stoppers on the shaft body between the star wheel blades, which is characterized in that a cone hole is provided in the star wheel shaft body and a cone sleeve configured therewith is provided; the radius of the cone sleeve An opening is provided on the top; the cone sleeve and the key groove provided on the sleeve are matched with the motor main shaft.

In the present invention, in order to achieve the purpose that a star wheel can be matched with a variety of motor spindle diameters, the size of the cone sleeve and the star wheel cone hole is fixed, but the inner hole and key groove of the cone sleeve are according to the motor spindle diameter. Choose it.

Preferably, the left cover and the right cover are provided with protrusions near the star wheel shaft, and the star wheel blades have a T-shaped structure, and the shape is adapted to the cavity surrounded by the left cover, the right cover, and the friction shell. In this way, the length of the structure of the present invention can be shortened while ensuring the effective width.

Through the series optimization design of the two parameters of the effective diameter and effective width of the star wheel, the preconditions to ensure that the matching power is 3 ~ 5600kw and the input speed is 500 ~ 3000r / min are unchanged and the fill factor of the transmission medium is within the allowable range Next, the steps of adjusting the effective diameter and compressing the effective width are adopted, together with the realization of a star wheel and a variety of motor shaft diameters, so that the original series of hundreds of models and specifications are compressed into more than a dozen of the present invention. .

Preferably, rib rings are provided on both sides of the base of the T-shaped star wheel blade. In order to strengthen the bending and torsional strength on both sides, and to prevent the red dandelion powder from penetrating into the bearing.

As a preference, the difference L between the length of the star wheel shaft body and the minimum main shaft length in the supporting motor group is 20 nm! ~ 60mm; and the mounting distance between adjacent two end faces is 2 ~ 6 mm. When the present invention is connected to a motor with a large main shaft length, the star wheel shaft end is kept at a distance from the motor main shaft shoulder. The purpose of leaving L is when the motor or the load spindle extends into it, and the installation distance between adjacent two end faces is 2 ~ 6 mm, the existing equipment technology can be replaced with the original short ordinary coupling when it is technologically transformed. the goal of.

Preferably, the opening is a radial opening, and its size is 1 to 4 mm; and an axial groove is provided on the inner side of the cone sleeve. In this way, the cone sleeve can be conveniently fixed in the cone hole.

Preferably, the left cover is integrated with the half body through a stud, an end face of the half body is provided with a baffle plate and bolted to the half body to limit the pin from channeling outward; the half body is provided with a tapered hole, A tapered sleeve configured therewith is arranged on the tapered sleeve; the tapered sleeve and the upper key groove are matched with the load spindle.

Preferably, the interface between the taper sleeve and the taper hole is provided with 2 to 10 locking holes and 1 to 4 pull-out holes.

Preferably, the locking hole is a deep long threaded hole on the star wheel taper hole and a straight hole on the taper sleeve shaft body; the pull-out hole is a shallow straight hole on the star wheel taper hole, and the taper sleeve The shaft body has deep and long threaded holes.

In addition, a ball bearing is provided between the left end of the star wheel shaft body and the left cover, and the ball bearing is fastened by a gland and a screw; A needle bearing is arranged between the right end of the body and the right cover, and the needle bearing is limited by a retaining ring. Needle bearings play a role of radial positioning during installation, and are not positioned in the axial direction, which can facilitate loading and unloading. Ball bearings play a positioning role in both axial and radial directions. Because the left end of the star wheel matches the shaft diameter of the bearing and the tapered hole that matches the tapered sleeve, and the left cover is installed to align the reference circle and the shaft hole, and the right cover bearing hole and the outer circle that matches the tapered sleeve are all in The process is completed during the process installation, and the coaxiality is high. In addition, the installation of the half body is aligned with the reference circle and the tapered hole that is matched with the tapered sleeve is also completed in a process installation. The coaxiality is high, thereby improving the transmission system. Smoothness and reliability, good transmission quality.

In the present invention, before the taper sleeve matching the star wheel and the half body is locked, its inner hole is loosely matched with the motor or the load spindle. After the star wheel or half body is pushed into the main shaft with the taper sleeve, tighten the screws on the taper sleeve according to the required torque to achieve reliable connection and realize power transmission. When disassembling, it is only necessary to unscrew the locking nail and screw it into the pull-out hole in the taper sleeve with the threaded hole to pull out the taper sleeve and loosen the main shaft for simple and convenient disassembly.

Therefore, the mechanical soft starter provided by the present invention has the following advantages: 1. The purpose of matching a star wheel with a variety of motor spindle diameters is achieved, and hundreds of models and specifications of the original series are compressed to more than a dozen of the present invention. 2. The main body of the product can realize large-scale production and can be provided with a certain amount of storage. When supplying, you only need to select the corresponding cone sleeve and stopper according to the order data provided by the customer, and then fill the transmission medium according to the data provided by the computer. Can be delivered immediately, greatly improve the delivery time, and improve production efficiency. 3. The structure length has good compatibility with existing equipment, which is conducive to the technical transformation of customers based on existing equipment. 4. The transmission process is stable and reliable, the transmission quality is good, and the disassembly and installation are very convenient.

BRIEF DESCRIPTION OF THE DRAWINGS

Figure 1 is a side view of a half section of the present invention;

FIG. 2 is a cross-sectional view taken along A-A of FIG. 1;

FIG. 3 is a cooperation characteristic diagram of the present invention, a motor, and several common working machines;

FIG. 4 is a comparison diagram of energy consumption of the present invention and an ordinary coupling during the startup process;

Figure 5 is the process of joining the active and passive shafts when the invention is started. The best way to implement the invention

The technical solutions of the present invention will be further specifically described below through the embodiments and the accompanying drawings.

Embodiment 1: A star wheel 10 is connected to a motor through a cone sleeve 1 in a shaft hole thereof, and the star wheel is an active part of the present invention. A bearing 4 is provided on the outer circle at the left end of the star wheel shaft body, and is installed in the bearing hole of the left cover 7, and then the cover 2 and the screw 3 are used to fasten the position and seal. The outer circle of the right end of the star wheel shaft body is combined with the bearing 14 酉 5, and the bearing is installed in the bearing hole of the right cover 12, and the retaining ring 13 is used for positioning. Seal rings 15 are designed on the outer circles of the star wheel shaft and the left and right covers, respectively, to prevent the infiltration of red powder Bearings. The star wheel shaft body is provided with a T-shaped blade 27 in the middle, and a rib ring 29 is provided on the concave sides. The shaft body between the star wheel blades is a hexagonal body, and a combiner 22 is provided thereon. A friction shell 8 is provided between the left cover and the right cover and the effective diameter of the star wheel blades, and they are integrated by fasteners 5 and 16. The containment surface surrounded by the left cover, the right cover and the friction cover shell and the cavity of the star wheel blade containment surface is filled with a certain number of transmission media 11, and the periphery between the containment surface and the containment surface is provided with The contact gaps and the bearings 4 and 14 constitute the "flexible coupling" of the present invention to realize its transmission function. A detection plug 9 is provided on the periphery of the friction shell to periodically and randomly check the wear of the steel balls and make up for the filled steel balls. The matching cone surface fan of the cone sleeve and the star wheel is provided with 2 to 10 locking holes 25 and 1 to 4 pull-out holes 26. A radial opening 28 is provided on the radius of the cone sleeve, and its size is 2 mm. The locking hole 25 is a long threaded hole on the star wheel cone hole 24 and a straight hole on the cone sleeve cone. By tightening the hexagon socket screw in the locking hole, the cone sleeve is pressed into the star wheel cone hole. At the same time, the opening 28 on the radius of the taper sleeve is contracted, and the taper sleeve and the upper key groove 23 thereof lock the motor or the load spindle and realize power transmission. The pull-out hole is a shallow straight hole on the inner cone hole of the star wheel, and a deep thread hole on the outer cone of the cone sleeve. When the screw in the locking hole is removed and screwed into the pull-out hole, Pull out the taper sleeve while loosening the connection to the spindle. The above star wheel, the left cover, the right cover, the friction shell, the pressure cover, the retaining ring, the bearing, the transmission medium and the fastener, etc. together constitute the right assembly of the present invention.

The half body 21 is connected to the load main shaft through a locking cone sleeve, and the half body and the right assembly are connected into a body through a pin 18, and the baffle 19 and the bolt 20 are used to prevent the pin from axially escaping. The above is the composition of the present invention, in which the star wheel is the active part, and the rest constitute the passive body.

Embodiment 2: The combiner 22 is a technical improvement of the combiner of the centrifugal moment-limiting steel ball coupling, that is, the ferrite magnet tile permanent magnet block of the original coupler is changed to a neodymium iron boron strong magnet Rectangular permanent magnet block. This magnetic block has 10 times the magnetic force of the former, has a small size and a small footprint, and can replace the application of the original brake block resistor and the transmission of a 2-pole or 4-pole large motor.

During the operation of the invention, the star wheel is driven by a motor to drive, and the transmission medium is driven by the star wheel blades under the dual effects of centrifugal force and the resistance of the damper. Generate friction torque to transfer power. When the friction torque M _{F is} greater than the drag torque of the load, it can smoothly and reliably drag the running load at steady-state and constant-speed operation, or start the original stationary load and accelerate to the working speed to enter the steady-state operating condition. Otherwise, the speed of the running load will be reduced or even blocked (overload slip), or the load cannot be started and maintained at its original stationary state, and the soft-start motor (start slip) is unloaded.

The performance of the present invention will be described in detail below with reference to the accompanying drawings 3-5.

1. No-load soft start performance. The condition for realizing the soft start of the motor at no load is that the external characteristic diagrams of both the soft starter and the working machine must have intersections, and the corresponding speed n _{t is} called the load start critical speed. A speed time plot showing the motor and the working machine of the present invention, FIG. 5 (n- t I _a graph showing the relationship between the rotational speed of the motor during startup versus time curve I _b represents the relationship of the rotation speed of the working machine during the startup process as a function of time. At startup, when the motor rotational speed _{_{_{n d ≤n t, M F ≤M}}} L, maintaining the original static load, and the motor star wheel is approximated with the first to load starting, stable and rapid rise in the curve segment 0 of _13, to (0.85 —0.9) n _k . The flexible joint of the present invention slips, and the slip is maximum at n _t , and the rotation speed changes like a curve

The speed of the eighth and eighth sections of 1 ₃ increased from (0.85 to 0.9) n _k to n _k . When n _d > n _t , beij ij M _F > M _L , the motor starts to drag the load into the second step start-up phase, and its starting additional torque M _F -ML_ determines the angular acceleration of the load start, the flexible joint until complete synchronization slip is reduced by the flexible coupling into a rigid coupling, speed changes the curve section ₁₃ of the BC, reduced n _F. From the start of the second step, the section of the working machine to the rigid connection such as the curve I _b has been rising steadily, and then the motor and the load are raised to a stable operating condition at a common speed, as shown in the CD section of FIG. 5. Therefore, the larger the n _t , the better the no-load soft-start performance. The height of n _t has a direct impact on the external characteristics of the starter and the working machine.

Figure 3 is a torque-speed relationship curve (M_n diagram). If the present invention is not provided with a resistor, its external characteristic function formula M _F = f (n ² ), and its graph is a quadratic parabola OAi F passing through the origin of the Cartesian coordinate. The working machine type has a centrifugal type

M, = f (n ² ), constant slope type M, -f (n), constant torque type M, = constant, constant power type M ,,- ¹ ) and the like. Taking a centrifugal working machine as an example, its external characteristic is a quadratic parabola 0 ₂ 1 passing through 0 ₂ points on the ordinate of the Flute coordinate. If the present invention is not provided with a stopper, the external characteristic intersection point is A _1; The torque 1 \ / ^ and n _t1 corresponding to this point are very low. In this way, not only the speed gradient of the motor at the no-load start is small and the effect is poor, but also when the load is started in the second step, the additional start torque (ie M _F1 -M _U ) is small, which delays the load start process and delays The working machine is put into steady-state operation. When a stopper is provided in the present invention, the transmission medium can be subjected to the dual effects of centrifugal force and resistance of the stopper during the startup process, and its external characteristic graph is improved to change according to O ^ FC, and the intersection point is increased to A ₂ , the eight _second intersection critical speed corresponding to the load start n _t2> n _t1, n so as to achieve good results greatly improved performance of the soft start load _T (see FIG. 3).

FIG. 4 is a comparison diagram (I-t diagram) of the current during the startup process of the present invention and the startup process of a common coupling. The curve I represents the current change using the present invention, and the curve II represents the current change using a common coupling. In curve I the motor starting current l _Q output drops sharply linear load segment to 0.7I _Q, the first to substantially linear down to l _k, in this case the maximum slip flexible coupling stage, and then gradually rises; rigid coupling stage Drop to operating current l _k . Curve II drops slowly until it reaches the operating current l _k . Experiments prove that the energy consumption during the startup process of the present invention is only 20% to 25% of the ordinary coupling.

Second, regarding the overload protection performance (see Figure 3). The present invention cooperates with a motor and makes the intersection point of the external characteristic graphs of the two be F, which is between the maximum torque M _m and the rated torque M _{k of the} motor, and the corresponding rotation speed is n _F. Thus, the present invention not only has The motor's overload protection performance can also exert its characteristics of allowing instantaneous overload. When the motor is operating under rated conditions, the torque M _k and the rotation speed n _k . At this time, the friction torque M _c = kM _{k provided} by the present invention and the torque reserve coefficient K> 1. The present invention is rigid. It can connect power smoothly and reliably to ensure constant transmission speed ratio. When the motor output torque varies with the load resistance torque,

When the moment M _k increased safety limit value [M _F] overload present invention, the rotational speed decreased slightly by n _k n _F, while the present invention by the friction torque rapidly dropped M _e [M _F], turn The moment reserve coefficient drops to K = 1, and a "slip" trend appears at point F, and the rigid connection begins to change into a flexible connection. This overload slip disengages the motor from the load without causing overload stalling and burnout and damage. However, long-term overload slip will cause the thermal annealing failure of the friction pair and failure of the flexible connection, and eventually burn the motor. For this reason, for severe long-term overload operating conditions and remote automatic control occasions, an infrared slip detection device should be set to monitor. When the overload slip causes the working machine speed to fall 10% to 20% of its working speed, a signal is output and an alarm is issued. And parking. ¾] "In occasional occasions of overload and stall, the pin of the present invention can also prevent overheating caused by overload slip. When the temperature rises to 165 degrees Celsius, the pin can be softened and sheared to stop.

3. Coordination of multi-machine drive load distribution and synchronous transmission performance. This performance is essentially an extension of the no-load starting and overload protection performance, except that the intersection point with the external characteristic graph of the motor is designed below the [M _F ] pole F. Coordination performance can simply and reliably solve the three problems of sequential start of multi-point drive, synchronous load with balanced load and overload protection.

Claims

Claim

1. A mechanical soft starter comprising a star wheel provided with blades connected to a main shaft of a prime mover, a friction shell provided outside and connected to left and right covers, and a steel ball centrifugal body interposed therebetween, The shaft body is provided with several stoppers, which is characterized in that a tapered hole (24) is provided in the star wheel shaft body, and a tapered sleeve (1) configured therewith is provided on the shaft body _; the tapered sleeve (1) An opening (28) is provided on the radius; the cone sleeve (1) and the key groove (23) provided on the radius match the main shaft of the motor.

2. The mechanical soft starter according to claim 1, characterized in that the left cover (7) and the right cover (12) are provided with protrusions near the star wheel shaft, and the star wheel blades (27) are T The shape structure is suitable for the cavity enclosed by the left cover (7), the right cover (12) and the friction shell (8).

3. The mechanical soft starter according to claim 2, characterized in that rib rings (29) are provided on both sides of the base of the T-shaped star wheel blade (27).

4. The mechanical soft starter according to claim 1, characterized in that the difference L between the length of the star wheel shaft body and the minimum main shaft length in the supporting motor group is 20mn! ~ 60mm _; and the installation distance between adjacent two end faces is 2 ~ 6mm.

5. The mechanical soft starter according to claim 1, characterized in that the opening (28) is a radial opening, the size of which is 1 to 4 mm, and is provided on the inner side of the cone sleeve (1). There are axial grooves (30).

6. The mechanical soft starter according to claim 1 or 2 or 3 or 4 or 5, characterized in that the left cover (7) is connected to the half body (21) by a pin (18), The pin is provided with a baffle plate (19) and a bolt (20); the half body (21) is provided with a tapered hole (24), and a tapered sleeve (1) configured therewith is provided on the half body (21); (1) and its keyway

(23) Matching with the load spindle.

7. The mechanical soft starter according to claim 1 or 2 or 3 or 4 or 5, characterized in that 2 to: 10 are provided on an interface of the tapered sleeve (1) and the tapered hole (24). Locking holes (25) and 1-4 pull-out holes (26).

8. The mechanical soft starter according to claim 7, characterized in that the locking hole (25) is in a star wheel cone hole

(24) is a deep and long threaded hole, and a straight hole is formed on the shaft of the taper sleeve (1); the pull-out hole (26) is a shallow straight hole on the star wheel taper hole (24), and the taper sleeve (1) ) The shaft body is deep and long threaded holes.

9. The mechanical soft starter according to claim 1 or 2 or 3 or 4 or 5, characterized in that a ball bearing (4) and a ball are provided between the left end of the star wheel shaft body and the left cover (7). The bearing is fastened by a gland (2) and a screw (3); a needle roller bearing (14) is arranged between the right end of the star wheel shaft body and the right cover (12), and the needle roller bearing (14) is a retaining ring (13) ) Limit.

10. The mechanical soft starter according to claim 7, characterized in that a ball bearing (4) is provided between the left end of the star wheel shaft body and the left cover C7), and the ball bearing is a gland (2) and The screw (3) is fastened; the right side of the star wheel shaft body A needle bearing (14) is arranged between the end and the right cover (12), and the needle bearing (14) is limited by a retaining ring (13).