CN209782417U - lamp set - Google Patents

Abstract

The utility model belongs to the technical field of lamps, in particular to a lamp, which comprises a lamp post, a slider, a limiting block, a gear and a wire winding wheel, wherein the slider is vertically and slidably arranged in the hollow lamp post, and the limiting blocks are respectively and slidably arranged in two sliding grooves symmetrically distributed on the inner wall of a transmission cavity of the slider; when the utility model is maintained, only the crank at the lower end of the lamp post needs to be shaken, so that the slider provided with the bulb is descended to the mounting groove, and then the bulb is replaced, and the whole process does not need maintenance personnel to climb to carry out high-altitude operation, thereby avoiding the danger brought by the high-altitude operation; the utility model discloses compare in traditional lamps and lanterns appearance simple structure and pleasing to the eye, the whole process of wire that the current conducting plate is connected can not participate in the action in addition, has avoided the wire and has followed the slider removal and the reciprocal quilt that leads to is buckled, effectively prolongs the life of this wire.

Description

Lamp set

Technical Field

The utility model belongs to the technical field of lamps and lanterns, especially, relate to a lamp.

Background

The traditional overhead lamp with the upright posts is visible at any place on two sides of a road at present, the lamp heads are basically arranged at the top ends of the upright posts, when a circuit is overhauled or a bulb is replaced, the lamp with the structure needs to be manually climbed or a ladder is used for maintaining the lamp at the top ends of the lamp, the whole process is overhead operation, the operation is inconvenient, and high danger is caused, so that the operation difficulty of maintenance personnel is increased; the existing lamps also have the condition that the lamps do not need to climb manually or use a ladder during maintenance, but most of the overhead lamps adopt a method that the lamp upright rods are bent around hinge points or stretched and retracted in an up-and-down sliding manner for maintenance, the upright rod structures of the lamps are complex, the lamps are likely to be not bent or stretched in the use process, the implementation of the lamp maintenance work is influenced, the difficulty of the whole maintenance work is increased, and the working efficiency of the lamp maintenance is greatly reduced; in addition, the lamp capable of bending the vertical rod or sliding the vertical rod up and down is difficult to compare with the traditional vertical rod in appearance image due to the problem of the design of the structure of the lamp. The utility model relates to a lamps and lanterns solve above-mentioned problem.

SUMMERY OF THE UTILITY MODEL

In order to solve the above-mentioned defects in the prior art, the utility model discloses a lamp, it adopts following technical scheme to realize.

In the description of the present invention, it should be noted that the terms "inside", "below", "upper" and the like indicate the position or positional relationship based on the position or positional relationship shown in the drawings, or the position or positional relationship which is usually placed when the products of the present invention are used, and are only for convenience of description and simplification of the description, but do not indicate or imply that the equipment or elements indicated must have a specific position, be constructed or operated in a specific orientation, and thus, should not be construed as limiting the present invention. Furthermore, the terms "first," "second," and the like are used merely to distinguish one description from another, and are not to be construed as indicating or implying relative importance.

A light fixture, characterized by: the lamp comprises a lamp post, a cover plate, a lamp shade, a current-conducting plate, a sliding block, limiting blocks, a limiting spring, a rack, a gear, a first fixed pulley, a lamp socket, a bulb, a second fixed pulley, a wire-winding wheel and a transmission shaft, wherein the sliding block is vertically and slidably installed in the hollow lamp post, the limiting blocks are respectively and slidably installed in two sliding grooves symmetrically distributed on the inner wall of a transmission cavity of the sliding block, and the two limiting blocks are respectively matched with two limiting grooves on the inner wall of the lamp post and the current-conducting plate installed in the limiting; two limiting blocks are respectively and fixedly provided with a rack, and the two racks are simultaneously meshed with a gear arranged on the inner wall of the transmission cavity; the first fixed pulley is arranged in the transmission cavity through a shaft and is positioned between the two limiting blocks.

The two limiting springs which are symmetrically arranged on the inner wall of the transmission cavity and are always in a stretching state respectively exert the resetting function on the two limiting blocks; a lamp socket with a live wire joint and a zero line joint at the tail part is arranged in an installation hole which is positioned on the upper end surface of the sliding block and is vertically communicated with the transmission cavity, a bulb is arranged in the lamp socket, and the bulb penetrates through a cover plate arranged at the upper end of the lamp post to be matched with a lampshade arranged on the cover plate; the upper end of the inner wall of the lamp post is provided with a second fixed pulley, the lower end of the lamp post is coaxially provided with two wire winding wheels through a transmission shaft, and one end of the transmission shaft, which is positioned at the outer side of the lamp post, is provided with a crank; the two wire winding wheels respectively correspond to the first fixed pulley and the second fixed pulley above.

A first rope wound on one of the wire winding wheels is upwards connected with the end face of one limiting block by bypassing the first fixed pulley through a rope hole positioned on the lower end face of the sliding block and communicated with the transmission cavity, and a second rope wound on the other wire winding wheel is upwards connected with the upper end face of the sliding block by bypassing the second fixed pulley through a rope groove on the side face of the sliding block; the first cord is wound in the opposite direction to the second cord.

As a further improvement of the present technology, the lamp post inner wall is symmetrically provided with two first guide grooves, two opposite side surfaces of the sliding block are respectively provided with a first guide block, and the two first guide blocks respectively slide in the two first guide grooves on the lamp post inner wall, so as to ensure that the sliding block moves vertically along the lamp post inner wall.

As a further improvement of the present technology, two second guide grooves are symmetrically formed in two side walls of the sliding groove, two second guide blocks are symmetrically installed on two side end faces of the limiting block, and the two second guide blocks slide in the two second guide grooves respectively to ensure: when the limiting block relieves the motion limitation on the sliding block, the second guide block does not move any more due to the length limitation of the second guide groove, and the first rope which is continuously wound can pull the sliding block to move downwards sequentially through the limiting block and the second guide block; the irreversible deformation caused by the excessive stretching of the limiting spring due to the fact that the first rope pulls the sliding block to move downwards through the limiting block, the tension spring plate and the limiting spring is avoided.

As a further improvement of the technology, the part of the first rope, which is positioned between the limiting block and the first fixed pulley, is parallel to the sliding direction of the limiting block in a stretched state, so that the limiting block is ensured to contract inwards along the second guide groove and remove the limitation on the movement of the sliding block, the pressure of the limiting block on the bottom surface of the sliding groove is minimum, the friction force caused by the movement of the limiting block is minimum, and the limiting block can contract quickly and remove the limitation on the movement of the sliding block and simultaneously save the physical force of an operator.

The lower end face of the limiting block is a smooth surface, and the limiting block can slide horizontally along the sliding groove.

As a further improvement of the technology, the two conducting plates are respectively connected with a live wire and a zero line of an external power supply through leads, the limiting block corresponding to the live wire is connected with a live wire joint at the tail part of the lamp socket through a lead, and the limiting block corresponding to the zero line is connected with a zero line joint at the tail part of the lamp socket through a lead.

As a further improvement of the technology, an operation groove is formed in the side face of the lower end of the lamp pole, the crank is hidden in the operation groove, a cover capable of being locked is arranged at the notch of the operation groove, and only when a worker or a manager of the lamp possesses a key, the cover on the operation groove can be opened for normal operation.

As a further improvement of the technology, an installation groove communicated with the inside of the lamp post is formed in the operation groove; when the bulb descending along with the sliding block from the inside of the lamp rod reaches the mounting groove, the bulb can be replaced through the mounting groove.

The utility model discloses well stopper is made by conducting material, and rack, gear, slider, rope are made by non-conducting material.

The utility model provides a connecting wire between stopper and the lamp socket is in the state of lax all the time, and the motion of stopper can not make connecting wire between stopper and the lamp socket be very straight and lead to the electricity between the two to be connected and interrupt.

The utility model discloses well spacing spring is in tensile state all the time, is in order to make two stoppers respectively with be located the current conducting plate in close contact with of two spacing inslots, form good electric conductivity.

The utility model discloses there is frictional force between the side of well slider and the lamp pole inner wall, and the dead weight of slider is less than frictional force between the two, avoids when the stopper removes the motion restriction to the slider to fall down fast from the lamp pole top by the dead weight and cause the damage.

Compared with the traditional lamp, the utility model adopts the matched transmission of the wire winding wheel and the rope to avoid the slipping phenomenon in the matched transmission process of the belt pulley and the belt, and the matched transmission cost of the wire winding wheel and the rope is far lower than the matched transmission cost of the chain and the chain wheel; the limiting block and the limiting groove are in straight surface fit instead of inclined surface fit, so that the position of the sliding block at the top end of the lamp post can be better fixed; when the utility model is maintained, only the crank at the lower end of the lamp post needs to be shaken, so that the slider provided with the bulb is descended to the mounting groove, and then the bulb is replaced, and the whole process does not need maintenance personnel to climb to carry out high-altitude operation, thereby avoiding the danger brought by the high-altitude operation; the utility model discloses simple structure has better result of use.

Drawings

Fig. 1 is an overall schematic view of a lighting device.

Fig. 2 is a schematic cross-sectional view of an illumination device.

Fig. 3 is a schematic view of the section of the limiting block, the limiting spring, the rack and the gear.

Fig. 4 is a schematic diagram of a limiting block, a sliding block, a lamp post and a conductive plate.

FIG. 5 is a schematic view of the slider and the first guide block.

FIG. 6 is a cross-sectional view of the inner slide groove and the second guide groove of the slider.

Fig. 7 is a schematic view of a light pole.

Figure 8 is a cross-sectional view of the first channel in the light pole.

Fig. 9 is a schematic cross-sectional view of a limiting groove in a lamp post.

FIG. 10 is a cross-sectional view of the lamp post, the wire winding wheel and the transmission shaft.

Fig. 11 is a schematic section view of the limiting block, the second guide block, the sliding block and the lamp post.

Fig. 12 is a schematic diagram of the cord principle.

Number designation in the figures: 1. a lamp post; 2. an operation slot; 3. mounting grooves; 5. a first guide groove; 6. a limiting groove; 7. a cover plate; 8. a lamp shade; 9. a conductive plate; 10. a slider; 11. a transmission cavity; 12. rope grooves; 13. a sliding groove; 14. a second guide groove; 15. a rope hole; 16. mounting holes; 17. a first guide block; 18. a limiting block; 19. a second guide block; 20. a tension spring plate; 21. a limiting spring; 22. a rack; 23. a gear; 24. a first fixed pulley; 25. a lamp socket; 26. a bulb; 27. a second fixed pulley; 28. winding the wire wheel; 29. a drive shaft; 30. a first rope; 32. a second rope.

Detailed Description

The attached drawings are schematic diagrams of the implementation of the present invention in order to understand the structural operation principle. The specific product structure and the proportional size are determined according to the use environment and the conventional technology.

as shown in fig. 1, the lamp comprises a lamp post 1, a cover plate 7, a lampshade 8, a conductive plate 9, a slider 10, a limiting block 18, a limiting spring 21, a rack 22, a gear 23, a first fixed pulley 24, a lamp socket 25, a bulb 26, a second fixed pulley 27, a wire winding wheel 28 and a transmission shaft 29, wherein as shown in fig. 2, the slider 10 is vertically and slidably mounted in the hollow lamp post 1; as shown in fig. 3, 4 and 9, two sliding grooves 13 symmetrically distributed on the inner wall of the transmission cavity 11 of the sliding block 10 are respectively provided with a limiting block 18 in a sliding manner, and the two limiting blocks 18 are respectively matched with two limiting grooves 6 on the inner wall of the lamp post 1 and a conductive plate 9 arranged in the limiting grooves 6; as shown in fig. 3 and 11, two limit blocks 18 are respectively and fixedly provided with a rack 22, and the two racks 22 are simultaneously meshed with a gear 23 arranged on the inner wall of the transmission cavity 11; as shown in fig. 4 and 11, the first fixed pulley 24 is mounted in the transmission cavity 11 through a shaft and located between the two limit blocks 18.

As shown in fig. 2 and 11, two limiting springs 21, which are symmetrically installed on the inner wall of the transmission cavity 11 and are always in a stretched state, respectively exert a reset function on the two limiting blocks 18; as shown in fig. 2, a lamp socket 25 having a live wire terminal and a neutral wire terminal at the tail is installed in an installation hole 16 located on the upper end surface of the sliding block 10 and vertically communicated with the transmission cavity 11, a bulb 26 is installed in the lamp socket 25, and the bulb 26 passes through a cover plate 7 installed at the upper end of the lamp post 1 to be matched with a lampshade 8 installed on the cover plate 7; as shown in fig. 4 and 10, the upper end of the inner wall of the lamp post 1 is provided with a second fixed pulley 27, the lower end of the inner wall of the lamp post 1 is coaxially provided with two wire winding wheels 28 through a transmission shaft 29, and one end of the transmission shaft 29, which is positioned at the outer side of the lamp post 1, is provided with a crank; as shown in fig. 4 and 12, the two winding rollers 28 correspond to the upper first fixed pulley 24 and the second fixed pulley 27, respectively.

As shown in fig. 12, a first rope 30 wound on one of the winding wheels 28 is connected with the end face of one of the limit blocks 18 by passing through a first fixed pulley 24 upwards through a rope hole 15 which is positioned on the lower end face of the sliding block 10 and communicated with the transmission cavity 11, and a second rope 32 wound on the other winding wheel 28 is connected with the upper end face of the sliding block 10 by passing through a second fixed pulley 27 upwards through a rope groove 12 on the side face of the sliding block 10; the first cord 30 is wound in the opposite direction to the second cord 32.

As shown in fig. 8, two first guide grooves 5 are symmetrically formed on the inner wall of the lamp post 1; as shown in fig. 5 and 6, two opposite side surfaces of the sliding block 10 are respectively provided with a first guide block 17, and the two first guide blocks 17 respectively slide in the two first guide grooves 5 on the inner wall of the lamp post 1, so as to ensure that the sliding block 10 moves along the inner wall of the lamp post 1 vertically.

As shown in fig. 6, two second guide grooves 14 are symmetrically formed on two side walls in the sliding groove 13; as shown in fig. 11, two second guide blocks 19 are symmetrically installed on two side end faces of the limiting block 18, and the two second guide blocks 19 respectively slide in the two second guide grooves 14 to ensure that: when the motion limit of the sliding block 10 is released by the limit block 18, the second guide block 19 does not move any more due to the length limit of the second guide groove 14, and the first rope 30 which is continuously wound can pull the sliding block 10 to move downwards through the limit block 18 and the second guide block 19 in sequence; the irreversible deformation caused by the excessive stretching of the limiting spring 21 due to the fact that the first rope 30 pulls the slider 10 to move downwards through the limiting block 18, the tension spring plate 20 and the limiting spring 21 is avoided.

As shown in fig. 12, the portion of the first rope 30 between the stopper 18 and the first fixed pulley 24 is parallel to the sliding direction of the stopper 18 in a stretched state, so as to ensure that the pressure of the stopper 18 on the bottom surface of the sliding groove 13 is minimum and the friction force caused by the movement of the stopper 18 is minimum in the process that the stopper 18 is retracted inwards along the second guide groove 14 and the limitation on the movement of the slider 10 is removed, which is beneficial for the stopper 18 to retract quickly and remove the limitation on the movement of the slider 10 and simultaneously save the physical strength of an operator.

The lower end surface of the limiting block 18 is a smooth surface, which is beneficial to the horizontal sliding of the limiting block 18 along the sliding groove 13.

As shown in fig. 2, the two conductive plates 9 are respectively connected with the live wire and the zero wire of the external power supply through wires, the limit block 18 corresponding to the live wire is connected with the live wire joint at the tail of the lamp holder 25 through a wire, and the limit block 18 corresponding to the zero wire is connected with the zero wire joint at the tail of the lamp holder 25 through a wire.

As shown in fig. 7 and 10, an operation slot 2 is formed on a side surface of a lower end of the lamp pole 1, the crank is hidden in the operation slot 2, a cover which can be locked is arranged at a notch of the operation slot 2, and only when a worker or a manager of the lamp has a key, the cover on the operation slot 2 can be opened for normal operation.

As shown in fig. 7 and 10, the operating slot 2 is provided with an installation slot 3 communicated with the lamp post 1; when the bulb 26 descending along with the slider 10 from the inside of the lamp rod 1 reaches the mounting groove 3, the bulb 26 can be replaced through the mounting groove 3.

The utility model discloses well stopper 18 is made by conducting material, and rack 22, gear 23, slider 10, rope are made by non-conducting material.

The utility model provides a connecting wire between stopper 18 and the lamp socket 25 is in the state of laxity all the time, and stopper 18's motion can not make the connecting wire between stopper 18 and the lamp socket 25 straighten and lead to the electricity between the two to be connected and interrupt.

The utility model discloses well spacing spring 21 is in tensile state all the time, is in order to make two stoppers 18 respectively with be located the current conducting plate 9 in two spacing grooves 6 in close contact with, form good electric conductivity.

The utility model discloses there is frictional force between the side of well slider 10 and the 1 inner wall of lamp pole, and the dead weight of slider 10 is less than frictional force between the two, avoids slider 10 to fall down fast from 1 top of lamp pole by the dead weight and cause the damage when stopper 18 removes the motion restriction to slider 10.

The utility model discloses a work flow: in an initial state, the two limiting blocks 18 are respectively positioned in the two limiting grooves 6 and are respectively in contact fit with the corresponding conducting plates 9, the first rope 30 and the second rope 32 are both in a tightening state, and the bulb 26 is positioned in the lampshade 8.

When the bulb 26 in the lampshade 8 needs to be replaced, the upper cover of the operation groove 2 at the lower end of the lamp post 1 is opened, the crank is shaken, and the crank drives two coaxial winding wheels 28 to synchronously rotate through a transmission shaft 29; a first rope 30 is wound around a coiler 28 corresponding to the first fixed pulley 24, and a second rope 32 is discharged from the coiler 28 corresponding to the second fixed pulley 27; the first rope 30 pulls the limiting block 18 connected with the first rope to slide inwards and contract along the second guide groove 14, the limiting block 18 drives the gear 23 to rotate through the rack 22 arranged on the limiting block 18, and the gear 23 drives the other limiting block 18 to slide inwards and contract along the corresponding second guide groove 14 through the other rack 22; the two limit blocks 18 are separated from the corresponding conductive plates 9 at the same time and gradually slide out of the corresponding limit grooves 6 to gradually relieve the limitation on the sliding block 10, and the two limit springs 21 are further stretched at the same time; at the same time, the second rope 32 gradually becomes slack; when the two limit blocks 18 slide out of the limit grooves 6 at the same time, the second guide blocks 19 on the two limit blocks 18 simultaneously reach the limit positions of the corresponding second guide grooves 14, the two limit springs 21 are stretched to the longest, the slack degree of the second rope 32 reaches the limit, and the slack amount of the second rope 32 at this time is equal to the sliding distance of any one of the limit blocks 18 along the corresponding sliding groove 13.

The handle is continuously shaken, the first rope 30 drives the sliding block 10 to overcome the friction between the first rope and the inner wall of the lamp post 1 to move downwards through the limiting block 18 and the two second guide blocks 19 arranged on the first rope, the first rope 30 is continuously wound, the second rope 32 is continuously released, the bulb 26 moves downwards along the inner wall of the lamp post 1 along with the sliding block 10, and the sliding block 10 pulls the upper end of the second rope 32 to move downwards; when the sliding block 10 drives the bulb 26 to move to the mounting groove 3, the crank is stopped to shake and the handle is retracted, and the two limiting blocks 18 press the inner wall of the lamp post 1 under the action of the two limiting springs 21, so that the friction force between the sliding block 10 and the inner wall of the lamp post 1 is increased, and the sliding block 10 is further prevented from continuously sliding downwards along the inner wall of the lamp post 1 after the handle is loosened; at this time, the first rope 30 is still in a stretched state, and the second rope 32 is in a relaxed state; then the bulb 26 is replaced from the mounting groove 3; after the bulb 26 is replaced, the crank is shaken in the reverse direction, the first rope 30 which is in the tight state before begins to be released and becomes loose gradually, and the second rope 32 which is in the loose state before begins to be wound and becomes tight gradually; when the second cord 32 is fully tightened, the amount of slack in the first cord 30 reaches a maximum, and the maximum amount of slack in the first cord 30 is equal to the previous maximum amount of slack in the second cord 32; and when the handle is further shaken, the second rope 32 pulls the sliding block 10 to move upwards against the friction force between the sliding block and the inner wall of the lamp post 1 and the self gravity, and the sliding block 10 pulls the upper end of the first rope 30 to move upwards through the second guide block 19 and the limiting block 18.

When two limiting blocks 18 arranged in the sliding grooves 13 at the two sides of the sliding block 10 meet with the two limiting grooves 6 on the inner wall of the lamp pole 1, the two limiting blocks 18 are instantly and simultaneously bounced into the two limiting grooves 6 respectively under the action of the limiting spring 21; the two limiting springs 21 are restored to the initial state, and the two limiting blocks 18 are respectively in contact fit with the conducting plates 9 in the two limiting grooves 6 again; since the maximum slack of the first rope 30 is equal to the previous travel of any stopper 18 sliding along the sliding groove 13, the stopper 18 which has completely entered the stopper groove 6 at this time returns the slack of the first rope 30, so that the first rope 30 is tightened again; the handle is further shaken, and due to the limitation of the two limit blocks 18 on the slider 10, the slider 10 cannot move upwards under the pulling action of the second rope 32, so that the handle cannot continuously swing around the transmission shaft 29, and the shaking of the handle is finished; at this time, the bulb 26 enters the lampshade 8, and the bulb 26 is replaced; during the whole process of replacing the bulb 26, the operator does not need to climb to carry out high-altitude operation, and the danger caused by climbing is avoided.

To sum up, the utility model has the advantages that: the utility model adopts the cooperation transmission of the wire winding wheel 28 and the rope to avoid the slipping phenomenon possibly occurring in the transmission process of the utility model by the cooperation of the belt pulley and the belt, and simultaneously, the cost of the cooperation transmission of the wire winding wheel 28 and the rope is far lower than the cost of the cooperation transmission of the chain and the chain wheel to realize the transmission of the utility model; the limiting block 18 and the limiting groove 6 are in straight surface fit instead of inclined surface fit, so that the position of the sliding block 10 at the top end of the lamp pole 1 can be better fixed; when the utility model is maintained, only the crank at the lower end of the lamp post 1 needs to be shaken, so that the slider 10 provided with the bulb 26 descends to the mounting groove 3, and then the bulb 26 is replaced, and the whole process does not need maintenance personnel to climb to carry out high-altitude operation, thereby avoiding the danger brought by the high-altitude operation; the utility model discloses compare in traditional lamps and lanterns appearance simple structure and pleasing to the eye, the whole process of wire that current conducting plate 9 is connected can not participate in the action in addition, has avoided the wire and has followed slider 10 to remove and the reciprocal quilt that leads to is buckled, effectively prolongs the life of this wire.

Claims (3)

1. A light fixture, characterized by: the lamp comprises a lamp post, a cover plate, a lamp shade, a current-conducting plate, a sliding block, limiting blocks, a limiting spring, a rack, a gear, a first fixed pulley, a lamp socket, a bulb, a second fixed pulley, a wire-winding wheel and a transmission shaft, wherein the sliding block is vertically and slidably installed in the hollow lamp post, the limiting blocks are respectively and slidably installed in two sliding grooves symmetrically distributed on the inner wall of a transmission cavity of the sliding block, and the two limiting blocks are respectively matched with two limiting grooves on the inner wall of the lamp post and the current-conducting plate installed in the limiting; two limiting blocks are respectively and fixedly provided with a rack, and the two racks are simultaneously meshed with a gear arranged on the inner wall of the transmission cavity; the first fixed pulley is arranged in the transmission cavity through a shaft and is positioned between the two limiting blocks;

The two limiting springs which are symmetrically arranged on the inner wall of the transmission cavity and are always in a stretching state respectively exert the resetting function on the two limiting blocks; a lamp socket with a live wire joint and a zero line joint at the tail part is arranged in an installation hole which is positioned on the upper end surface of the sliding block and is vertically communicated with the transmission cavity, a bulb is arranged in the lamp socket, and the bulb penetrates through a cover plate arranged at the upper end of the lamp post to be matched with a lampshade arranged on the cover plate; the upper end of the inner wall of the lamp post is provided with a second fixed pulley, the lower end of the lamp post is coaxially provided with two wire winding wheels through a transmission shaft, and one end of the transmission shaft, which is positioned at the outer side of the lamp post, is provided with a crank; the two wire winding wheels respectively correspond to the first fixed pulley and the second fixed pulley above;

A first rope wound on one of the wire winding wheels is upwards connected with the end face of one limiting block by bypassing the first fixed pulley through a rope hole positioned on the lower end face of the sliding block and communicated with the transmission cavity, and a second rope wound on the other wire winding wheel is upwards connected with the upper end face of the sliding block by bypassing the second fixed pulley through a rope groove on the side face of the sliding block; the first cord is wound in the opposite direction to the second cord.

2. A light fixture as recited in claim 1, wherein: two first guide grooves are symmetrically formed in the inner wall of the lamp post.

3. A luminaire as claimed in claim 1 or 2, characterized in that: install first guide block on two relative sides of above-mentioned slider respectively, two first guide blocks slide respectively in two first guide slots on the lamp pole inner wall.