CN201923602U

CN201923602U - Backstop with overload protection function

Info

Publication number: CN201923602U
Application number: CN2010206897198U
Authority: CN
Inventors: 叶笃孟
Original assignee: ZHEJIANG JINGJI ELECTROMECHANICAL CO Ltd
Current assignee: Shanghai fine base industry Co., Ltd.
Priority date: 2010-12-30
Filing date: 2010-12-30
Publication date: 2011-08-10
Anticipated expiration: 2020-12-30

Abstract

The utility model discloses a backstop with an overload protection function, which structurally comprises an outer ring, an inner ring and a wedge combination. The wedge combination is arranged in an outer ring inner circle between the inner ring and the outer ring, inner and outer contact ends, which are close to the inner ring and the outer ring, of each wedge are in arc-shaped design, and center points of the two arc-shaped contact ends of each wedge are non-coincident. By means of changing the shapes of the wedges in the backstop, the backstop skids during overload, when the wedges are wedged, wedged angles are enlarged gradually along with increase of torque, and when the wedged angles are larger than friction angles, the wedges can skid on surfaces of the inner ring and the outer ring. When the torque is reduced, the wedged angles are smaller than the friction angles, and the backstop realizes normal backstop. When overload impact force is reduced, the backstop can normally operate again. Use safety of equipment is greatly increased. Centers of the wedges are coincident to fixed centers thereof by means of calculation, so that the backstop is more stable in operation, and the service life of the backstop is prolonged.

Description

A kind of holdback with overload protection

Technical field

The utility model relates to holdback, specifically a kind of holdback with overload protection.

Background technology

The low speed holdback of using on the market is broadly divided into roller type brake and wedge backstop at present.Phase has been introduced contact low speed wedge backstop, i.e. NJ (NYD) type holdback in the early 1990s in China.Through long-term development, developed DSN type low speed holdback again.The inner thin oil lubricant that adopts of DSN type holdback has replaced the original grease lubrication that adopts, and has improved lubricating condition, has reduced friction coefficient, has prolonged service life.Its unique anti-rotation arm of force split design makes when belt feeder maintenance or other need reverse, and only need carry out shirtsleeve operation and can realize.And transmit compact conformation under the situation of identical check moment, in light weight, equipment under load condition, shut down safe and reliable, setting accuracy is low; can be widely used in promoting on the load transfer device, have on the equipment of check requirement as belt conveyer, bucket elevator, slat conveyer and other.

The principle of work of DSN type holdback is the inner ring rotation, and the outer ring maintains static, and a plurality of voussoirs are distributed in the space that is formed by inner ring and outer ring according to certain rules, and inner ring can only promptly be rotated in the forward to a direction rotation.By means of the overturning couple that spring produces on voussoir, the eccentric cylinder surface of voussoir is contacted gently with inside and outside circle.During contrarotation, voussoir under the effect of spring overturning couple, the wedging Internal and external cycle make its become one bear check moment (principle schematic---Fig. 1).

We were to calculate the check moment that holdback is born with the weight of material own when selecting holdback to belt feeder in the past.But we find that in practice holdback can satisfy under the situation of aforementioned calculation check moment fully, also can transship phenomenon once in a while.According to our long-term observation, belt feeder to the maximum impact that holdback produced be belt feeder is fully loaded shut down after, be not activated when restarting and when shutting down once more.At this moment holdback not only carries the check moment that weight produced of material, has also born the check moment of the antagonistic force generation of belt tension.Thereby cause holdback to produce the overload phenomenon.If want to bear fully the check moment that the impact of this period produces, then to up select one even several shelves during the holdback type selecting, this is very uneconomic.

The holdback overload generally following situation can occur: 1. when apparatus overload, the holdback outer ring is damaged or the internal part damage, be made the belt feeder reversing, cause whole holdback to lose efficacy and scrap.The belt feeder reversing also can damage the belt feeder parts sometimes, and just there is certain potential safety hazard in this.And the production cycle of a holdback is also longer, and the user produces and regards one's time as if it were gold, and this will bring serious loss to the user.2. when apparatus overload, skidding appears in holdback sometimes, and holdback is against incessantly making the belt back skating.But this phenomenon is only kept the time in several seconds or tens seconds, after check power that impulsive force produced reduces, and the normal again check of holdback, the belt feeder orderly closedown, start recovers normal operation.

Wedge backstop is in operation and sends unusual sound through regular meeting at present, and this is the sound of contact-impact between voussoir and the inside and outside circle.But, if not overlapping with the center of voussoir, the attachment point of voussoir can not strengthen this phenomenon, make it influence the stationarity of equipment operation.Reduce equipment life greatly.

The utility model content

(1) technical matters that will solve

The purpose of this utility model is the defective that exists at prior art, and a kind of holdback with overload protection is provided, and the appearance overload phenomenon that has solved the prior art existence can cause holdback to scrap the problem that reduces with the steady life-span of entire equipment operation.

(2) technical scheme

The technical scheme that its technical matters that solves the utility model adopts is: a kind of holdback with overload protection, its structure comprises outer ring and inner ring and is arranged on the wedge combinations in the circle in the outer ring between the Internal and external cycle, two outsides, outer ring are equipped with side plate by the outer-hexagonal bolt, then by socket head cap screw enclosing cover are installed on the side plate; Described wedge combinations is made up of voussoir, yoke plate, roller, pin, self lock nut, torsion spring; The voussoir of described space, roller are arranged on by pin and self lock nut on the yoke plate of both sides, and torsion spring is installed in the voussoir head, and described voussoir designs for arc near the inside and outside two contact ends of Internal and external cycle and the center-point of two arcs does not overlap.

The center-point of described voussoir and the voussoir attachment point on yoke plate overlaps.

Described thrust ring is installed on the side plate by socket head cap screw.

Described two blocks of side plates are being provided with groove with enclosing cover one side, and are provided with oil sealing in the groove.

Described biside plate below is connected with the arm of force by arm of force pin.

(3) beneficial effect

A kind of holdback with overload protection of the present utility model is compared with prior art, has following beneficial effect:

The utility model is on the technical foundation of original holdback, by changing the shape of the inner voussoir of holdback, allow holdback when overload, produce the phenomenon of skidding, voussoir wedge and the time, increase along with moment, wedging is contended cumulative big, and when wedging angle during greater than friction angle, voussoir will skid on inside and outside circle surface.When moment reduced, the wedging angle was less than friction angle, the normal check of holdback.So when the overload impulsive force reduces, can normally move again again.The safety in utilization of equipment improves greatly.By calculating the voussoir center is overlapped with its permanent center, make the holdback operation more steady, prolong the service life of holdback.

Description of drawings

Fig. 1 is the structural principle scheme drawing of the holdback of prior art;

Fig. 2 is the structural representation of the holdback of band overload protection of the present utility model;

Fig. 3 is the structural principle scheme drawing of the holdback of band overload protection of the present utility model.

Among the figure: 1, outer ring; 2, inner ring; 3, wedge combinations; 4, thrust ring; 6, socket head cap screw; 7, enclosing cover; 8, side plate; 9, outer-hexagonal bolt; 10, oil sealing; 11, arm of force pin; 12, the arm of force; 13, pin; 14, voussoir; 15, torsion spring; 16, roller; 17, yoke plate; 18, self lock nut.X, free rotation direction; Y, check direction.

The specific embodiment

Next explain below with reference to Figure of description a kind of holdback with overload protection of the present utility model being done.

A kind of holdback with overload protection, its structure comprises outer ring 1 and inner ring 2 and is arranged on the wedge combinations 3 in the circle in the outer ring between the Internal and external cycle, two outsides, outer ring are equipped with side plate 8 by outer-hexagonal bolt 9, then by socket head cap screw 6 enclosing cover 7 are installed on the side plate; Described thrust ring 4 is installed on the side plate by socket head cap screw.Described two blocks of side plates are being provided with groove with enclosing cover one side, and are provided with oil sealing 10 in the groove.Described biside plate below is connected with the arm of force 12 by arm of force pin 11.Described wedge combinations is made up of voussoir 14, yoke plate 17, roller 16, pin 13, self lock nut 18, torsion spring 15; The voussoir of described space, roller are arranged on by pin and self lock nut on the yoke plate of both sides, and torsion spring is installed in the voussoir head, and described voussoir designs for arc near the inside and outside two contact ends of Internal and external cycle and the center-point of two arcs does not overlap.

When inner ring 2 was rotated in the forward, voussoir 14 circular arcs contacted gently with inner ring 2 big cylindricals, outer ring 1 interior circle, and during contrarotation, voussoir 14 makes voussoir 14 and inside and outside circle wedging under the effect of torsion spring 15, bear check moment (principle is seen Fig. 1).In the processing column head is packed a plurality of circular holes of yoke plate 17 on voussoir 14 end faces, play fixation.Torsion spring 15 is installed in the voussoir head.Roller 16 is contained in inner ring 2 big cylindricals and the outer ring 1 between the circle, plays a part to support voussoir 14, and the processing column head is packed in a plurality of circular holes of yoke plate 17 on the end face, a fixation.Pin 13 cooperates with circular hole on the yoke plate 17, plays fixedly yoke plate effect.Self lock nut is contained on the outside thread of pin, tightens the back and constitute a wedge combinations.Another piece side plate 8 also is fixed on the outer ring 1 by outer-hexagonal bolt 9.2 oil sealings 10 are squeezed into respectively in the groove of two blocks of side plates 8.Enclosing cover 7 is installed on the side plate 8 by socket bolt, forms the main body of holdback.Connect with arm of force pin 11 between the main body and the arm of force 12.

(Fig. 3) as shown in the figure: the A point is the contact point during wedging between voussoir and the inner ring.The B point is the contact point during wedging between voussoir and the outer ring.The G point is the center of gyration of inside and outside circle, O ₁Point is the center of circular arc under the voussoir, O ₂Point is the center of circular arc on the voussoir, and the O point is the center of voussoir.α is the wedging angle of voussoir.

When check moment increases, the relative distance that AB is 2 increases, and makes wedging angle α increase, and when the α angle increased to friction angle greater than the wedging face, voussoir and inside and outside circle just keeping not static, had produced slide relative.And the α angle is being no more than under the situation of friction angle, does not skid.This patent is exactly by calculating, determine the angle at α angle, making it surpass friction angle (reason that current holdback damages is exactly dead at heavy overload situations lower wedge block and inside and outside circle wedge, produces severe plastic deformation) under the overload serious situation.On the contrary, under the operating mode of nonoverload, check is realized in the α angle in the check scope.Actv. has been avoided overload at that moment like this, makes equipment be not easy to damage, and don't has influence on ensuing normal use.This plays a good protective effect to equipment itself.

The center-point of described voussoir and the voussoir attachment point on yoke plate overlaps.Find the O point by calculating, be the center of voussoir.With the O point is the attachment point of voussoir, makes the holdback operation more steady like this, prolongs the service life of equipment.

The above embodiment is a kind of of the more preferably concrete embodiment of the utility model, and common variation that those skilled in the art carries out in the technical solutions of the utility model scope and replacement all should be included in the protection domain of the present utility model.

Claims

1. holdback with overload protection, its structure comprise outer ring and inner ring and are arranged on the wedge combinations in the circle in the outer ring between the Internal and external cycle that two outsides, outer ring are equipped with side plate by the outer-hexagonal bolt, then by socket head cap screw enclosing cover are installed on the side plate; It is characterized in that: described wedge combinations is made up of voussoir, yoke plate, roller, pin, self lock nut, torsion spring; The voussoir of described space, roller are arranged on by pin and self lock nut on the yoke plate of both sides, and torsion spring is installed in the voussoir head, and described voussoir designs for arc near the inside and outside two contact ends of Internal and external cycle and the center-point of two arcs does not overlap.

2. a kind of holdback with overload protection according to claim 1 is characterized in that: the center-point of described voussoir and the voussoir attachment point on yoke plate overlaps.

3. a kind of holdback with overload protection according to claim 1 and 2, it is characterized in that: described thrust ring is installed on the side plate by socket head cap screw.

4. a kind of holdback with overload protection according to claim 1 and 2 is characterized in that: described two blocks of side plates are being provided with groove with enclosing cover one side, and are provided with oil sealing in the groove.

5. a kind of holdback with overload protection according to claim 1 and 2 is characterized in that: described biside plate below is connected with the arm of force by arm of force pin.