CN210134690U

CN210134690U - Electronic communication tower

Info

Publication number: CN210134690U
Application number: CN201822274435.1U
Authority: CN
Inventors: 张邦; 杨欢; 刘朋飞
Original assignee: Henan Ju Jie Electronic Technology Co Ltd
Current assignee: Henan Ju Jie Electronic Technology Co Ltd
Priority date: 2018-12-30
Filing date: 2018-12-30
Publication date: 2020-03-10
Anticipated expiration: 2028-12-30

Abstract

The utility model provides an electronic communication tower, including the ejector pin, the riser, and a support, air spring and guide bar, the ejector pin is installed in the sleeve, and ejector pin right-hand member face welded connection seat I, install cardboard I in the connecting seat I, the welding of cardboard I is on splint outer arc side upper portion, the sleeve is installed on riser right flank upper portion, weld back force spring on the left end face in the sleeve, back force spring right-hand member and ejector pin left side welded connection, the riser is installed in last backup pad up end left side, the scaffold weldment is at riser right-hand member face downside, the air spring is installed in the support, air spring right-hand member welded connection seat II, install cardboard II in the connecting seat II, the welding of cardboard two right-hand member faces is in splint outer arc side lower part, the ejector pin is installed at the splint middle part, install clean cotton pad on the ejector pin: the automatic cleaning function of the communication tower column is realized, and the cleaning effect is good.

Description

Electronic communication tower

Technical Field

The utility model relates to an electronic communication tower belongs to the communication equipment field.

Background

The communication tower in the prior art cannot automatically clean the communication tower column, generally needs manual cleaning by operators, and is difficult to clean; communication tower elevation structure among the prior art is simple, and lift stability is not good, does not have spacing suggestion structure simultaneously, so needs an electronic communication tower to solve the above-mentioned problem that appears urgently.

SUMMERY OF THE UTILITY MODEL

The utility model aims at providing an electronic communication tower to solve the problem of proposing among the above-mentioned background art.

In order to achieve the above purpose, the present invention is realized by the following technical solution: an electronic communication tower comprises an upper supporting plate, a chassis, a communication wire and a communication tower column, wherein the upper supporting plate is welded on the upper side face of the chassis, an automatic cleaning mechanism is arranged on the left side of the upper end face of the upper supporting plate, a lifting mechanism is installed in the chassis, the communication wire is installed on the upper end face of the communication tower column, the communication tower column is installed in the chassis, the upper end of the communication tower column extends to the upper portion of the upper side face of the upper supporting plate, the automatic cleaning mechanism comprises a push rod, a vertical plate, a support, an air spring and a guide rod, the push rod is installed in a sleeve, the right end face of the push rod is welded with a first connecting seat, a first clamping plate is installed in the first connecting seat, the first clamping plate is welded on the upper portion of the outer arc-shaped side face of a clamping plate, the sleeve is installed on the, the device comprises a vertical plate, a support, a gas spring, a second clamping plate, a push rod, a cleaning cotton pad, a reset spring and a connecting plate, wherein the vertical plate is arranged on the left side of the upper end face of an upper supporting plate, the support is welded on the lower side of the right end face of the vertical plate, the gas spring is arranged in the support, the right end face of the gas spring is welded with the second connecting plate, the right end face of the second clamping plate is welded on the lower portion of the outer arc-shaped side face of a clamping plate, the push rod is arranged in.

Furthermore, cardboard one rotates through pivot one and one with the connecting seat and is connected, cardboard two rotates through pivot two and connecting seat two and is connected, the support rotates through pivot three and air spring to be connected, the transversal semicircular in shape of splint, in the use, communication tower extrudees splint, splint extrusion ejector pin, the ejector pin is to the left side removal in the sleeve to compress the return spring, cardboard one is rotating in connecting seat one through pivot one simultaneously, cardboard two is rotating in connecting seat two through pivot two, the air spring shrink simultaneously, the air spring left side is through pivot three at the support internal rotation, air spring and return spring make splint and communication tower surface laminating under the spring action, thereby make splint and communication tower closely laminate, improved the clean cleanliness factor in later stage.

Further, the transversal arc of personally submitting of clean cotton pad, the guide bar is installed in the guide hole, the guide hole is seted up at splint middle part position, in the use, the clean cotton pad of communication tower post extrusion, clean cotton pad drives the guide bar and removes in the guide hole, the guide bar removes and drives the connecting plate and remove, the connecting plate removes tensile reset spring, reset spring is under the resilience force effect, with the clean cotton pad with laminate mutually with communication tower post surface, the communication tower post removes, make clean cotton pad remove for the communication tower post, the dirty of adhesion is clear away on the clean cotton pad to the communication tower post, thereby the self-cleaning function of communication tower post has been realized, clean effect is good.

Further, self-cleaning mechanism is equipped with two sets ofly, two sets of self-cleaning mechanism bilateral symmetry installs on last backup pad up end, and two sets of self-cleaning mechanism structures are the same, and in the use, the communication tower post removes, makes two sets of clean cotton pads clear away the dirty on the communication tower post simultaneously, has improved dirty clear away scope greatly, and clean wide range.

Furthermore, the lifting mechanism comprises a lower support plate, a right nut seat, a right longitudinal screw rod, a right groove, a right belt wheel, a left groove, a left longitudinal screw rod, a left nut seat, a guide sleeve, an indicating rod and a limit baffle plate, wherein the lower support plate is arranged in the chassis, the upper end surface of the lower support plate is fixedly connected with the communication tower column through a bolt, the right nut seat is welded on the right end surface of the lower support plate, the right end of the right nut seat is arranged on the right longitudinal screw rod, the right longitudinal screw rod is arranged in the middle of the right groove, the right groove is arranged on the right side surface of the chassis, the right belt wheel is sleeved on the lower part of the annular side surface of the right longitudinal screw rod, the left belt wheel is sleeved on the lower part of the annular side surface of the left longitudinal screw rod, the left nut seat is welded on the left end surface of the lower, the left groove is formed in the left side face in the bottom frame, the guide sleeve is installed on the upper supporting plate, the indicating rod is installed in the guide sleeve, and the limiting baffle is welded to the upper end face of the indicating rod.

Further, the right nut seat is connected with the right longitudinal screw rod through a first ball nut pair, the left nut seat is connected with the left longitudinal screw rod through a second ball nut pair, the right belt wheel is connected with the left belt wheel through a synchronous belt, the lower end of the left longitudinal screw rod is connected with a driving motor, the driving motor is installed in a containing groove, the containing groove is formed in the left side of the lower end face of the underframe, the driving motor is connected with an external power supply through a connecting wire, in the using process, a driving motor circuit is switched on, the driving motor drives the left longitudinal screw rod to rotate in a left groove, the left longitudinal screw rod rotates to drive a left belt wheel to rotate, the left belt wheel drives a right belt wheel to rotate through the synchronous belt, the right belt wheel rotates to drive the right longitudinal screw rod to rotate, the first ball nut pair and the second ball nut pair convert the rotary motion of the right longitudinal screw rod and the left longitudinal screw rod into linear, the lower support plate drives the communication tower column to move upwards, so that the lifting function of the communication tower column is realized.

Furthermore, a fluorescent strip is pasted on the outer surface of the indicating rod, in the using process, the left nut seat and the right nut seat drive the lower supporting plate to move upwards, the lower supporting plate drives the communication tower column to move upwards, when the lower supporting plate contacts the indicating rod, the lower supporting plate drives the indicating rod to move upwards in the guide sleeve, and after the limiting baffle on the indicating rod is separated from the guide sleeve, a driving motor circuit is cut off, so that the limiting prompting function of the ascending height is realized, and the condition that the lower supporting plate ascends and exceeds the stroke is avoided.

The utility model has the advantages that: the utility model discloses an electronic communication tower, because of the utility model discloses add ejector pin, sleeve, return spring, riser, support, air spring, connecting seat one, cardboard one, splint, reset spring, clean cotton pad, guide bar, connecting plate, cardboard two and connecting seat two, realized the self-cleaning function of communication tower post, clean effect is good.

Because of the utility model discloses added bottom suspension fagging, right nut seat, the vertical lead screw in right side, right recess, right band pulley, left recess, the vertical lead screw in a left side, left nut seat, guide pin bushing, pilot lever and limit baffle, realized the raising and lowering functions of communication tower post.

Drawings

Other features, objects and advantages of the invention will become more apparent upon reading of the detailed description of non-limiting embodiments with reference to the following drawings:

fig. 1 is a schematic structural diagram of an electronic communication tower according to the present invention;

fig. 2 is a schematic structural view of an automatic cleaning mechanism in an electronic communication tower according to the present invention;

fig. 3 is an enlarged schematic structural diagram of a position a of an automatic cleaning mechanism in an electronic communication tower according to the present invention;

fig. 4 is a schematic structural view of a lifting mechanism in an electronic communication tower according to the present invention;

in the figure: 1-automatic cleaning mechanism, 2-upper supporting plate, 3-lifting mechanism, 4-underframe, 5-communication wire, 6-communication tower column, 101-ejector rod, 102-sleeve, 103-return spring, 104-vertical plate, 105-bracket, 106-gas spring, 107-connecting seat I, 108-clamping plate I, 109-clamping plate, 110-reset spring, 111-cleaning cotton pad, 112-guide rod, 113-connecting plate, 114-clamping plate II, 115-connecting seat II, 301-lower supporting plate, 302-right nut seat, 303-right longitudinal screw rod, 304-right groove, 305-right belt wheel, 306-left belt wheel, 307-left groove, 308-left longitudinal screw rod, 309-left nut seat, 310-guide sleeve, 311-indicator rod, 312-limit stop.

Detailed Description

In order to make the technical means, creation features, achievement purposes and functions of the present invention easy to understand, the present invention is further described below with reference to the following embodiments.

Referring to fig. 1-4, the present invention provides a technical solution: an electronic communication tower comprises an upper supporting plate 2, an underframe 4, a communication wire 5 and a communication tower column 6, wherein the upper supporting plate 2 is welded on the upper side surface of the underframe 4, an automatic cleaning mechanism 1 is arranged on the left side of the upper end surface of the upper supporting plate 2, an elevating mechanism 3 is arranged in the underframe 4, the communication wire 5 is arranged on the upper end surface of the communication tower column 6, the communication tower column 6 is arranged in the underframe 4, the upper end of the communication tower column 6 extends to the upper part of the upper side surface of the upper supporting plate 2, the automatic cleaning mechanism 1 comprises a mandril 101, a vertical plate 104, a bracket 105, a gas spring 106 and a guide rod 112, the mandril 101 is arranged in a sleeve 102, a first connecting seat 107 is welded on the right end surface of the mandril 101, a first clamping plate 108 is arranged in the first connecting seat 107, the first clamping plate 108 is welded on the upper part of the outer arc-shaped side surface of the clamping plate 109, the, the vertical plate 104 is arranged on the left side of the upper end face of the upper supporting plate 2, the support 105 is welded on the lower side of the right end face of the vertical plate 104, the gas spring 106 is arranged in the support 105, the right end of the gas spring 106 is welded with the second connecting seat 115, the second clamping plate 114 is arranged in the second connecting seat 115, the right end face of the second clamping plate 114 is welded on the lower portion of the outer arc-shaped side face of the clamping plate 109, the ejector rod 101 is arranged in the middle of the clamping plate 109, the cleaning cotton pad 111 is arranged on the right end face of the ejector rod 101, the connecting plate 113 is welded on the left end face of the ejector.

The lifting mechanism 3 comprises a lower support plate 301, a right nut seat 302, a right longitudinal screw rod 303, a right groove 304, a right belt wheel 305, a left belt wheel 306, a left groove 307, a left longitudinal screw rod 308, a left nut seat 309, a guide sleeve 310, an indicating rod 311 and a limit baffle 312, wherein the lower support plate 301 is arranged in the underframe 4, the upper end surface of the lower support plate 301 is fixedly connected with the communication tower column 6 through bolts, the right nut seat 302 is welded on the right end surface of the lower support plate 301, the right end of the right nut seat 302 is arranged on the right longitudinal screw rod 303, the right longitudinal screw rod 303 is arranged in the middle of the right groove 304, the right groove 304 is arranged on the right side surface of the underframe 4, the right belt wheel 305 is sleeved on the lower part of the annular side surface of the right longitudinal screw rod 303, the left belt wheel 306 is sleeved on the lower part of the annular side surface of the left longitudinal screw rod 308, the left nut seat, the left longitudinal screw rod 308 is arranged in the left groove 307, the left groove 307 is arranged on the left side surface in the bottom frame 4, the guide sleeve 310 is arranged on the upper support plate 2, the indication rod 311 is arranged in the guide sleeve 310, and the limit baffle 312 is welded on the upper end surface of the indication rod 311.

As an embodiment of the present invention: the first clamping plate 108 is rotatably connected with the first connecting seat 107 through a first rotating shaft, the second clamping plate 114 is rotatably connected with the second connecting seat 115 through a second rotating shaft, the support 105 is rotatably connected with the gas spring 106 through a third rotating shaft, the cross section of the clamping plate 109 is semicircular, in the using process, the clamping plate 109 is extruded by the communication tower 6, the push rod 101 is extruded by the clamping plate 109, the push rod 101 moves to the left in the sleeve 102 and compresses the return spring 103, meanwhile, the first clamping plate 108 rotates in the first connecting seat 107 through the first rotating shaft, the second clamping plate 114 rotates in the second connecting seat 115 through the second rotating shaft, meanwhile, the gas spring 106 contracts, the left side of the gas spring 106 rotates in the support 105 through the third rotating shaft, and the gas spring 106 and the return spring 103 rotate under the elastic force effect to enable the clamping plate 109 to be attached to the outer surface of the communication tower 6.

As an embodiment of the present invention: the cross section of the cleaning cotton pad 111 is arc-shaped, the guide rod 112 is installed in the guide hole, the guide hole is formed in the middle of the clamping plate 109, in the using process, the cleaning cotton pad 111 is extruded by the communication tower column 6, the cleaning cotton pad 111 drives the guide rod 112 to move in the guide hole, the guide rod 112 drives the connecting plate 113 to move, the connecting plate 113 moves to stretch the reset spring 110, the reset spring 110 enables the cleaning cotton pad 111 to be attached to the outer surface of the communication tower column 6 under the effect of resilience force, the communication tower column 6 moves, the cleaning cotton pad 111 moves relative to the communication tower column 6, dirt adhered to the communication tower column 6 is cleared by the cleaning cotton pad 111, the automatic cleaning function of the communication tower column 6 is achieved, and the cleaning effect is good.

As an embodiment of the present invention: automatic cleaning mechanism 1 is equipped with two sets ofly, and two sets of automatic cleaning mechanism 1 bilateral symmetry install on 2 up end of backup pad, and two sets of automatic cleaning mechanism 1 structures are the same, and in the use, communication tower 6 removes, makes two sets of clean cotton pads 111 clear away the dirty on communication tower 6 simultaneously, has improved dirty clear away scope greatly, and clean wide range.

As an embodiment of the present invention: the right nut seat 302 is connected with the right longitudinal screw 303 through a first ball nut pair, the left nut seat 309 is connected with the left longitudinal screw 308 through a second ball nut pair, the right belt wheel 305 is connected with the left belt wheel 306 through a synchronous belt, the lower end of the left longitudinal screw 308 is connected with a driving motor, the driving motor is arranged in a receiving groove, the receiving groove is formed in the left side of the lower end face of the underframe 4, the driving motor is connected with an external power supply through a connecting wire, in the using process, a driving motor circuit is switched on, the driving motor drives the left longitudinal screw 308 to rotate in a left groove 307, the left longitudinal screw 308 rotates to drive the left belt wheel 306 to rotate, the left belt wheel 306 drives the right belt wheel 305 to rotate through the synchronous belt, the right belt wheel 305 rotates to drive the right longitudinal screw 303 to rotate, the first ball nut pair and the second ball nut pair convert the rotary motion of the right longitudinal screw 303 and the left longitudinal screw 308 into linear motion, the, the lower support plate 301 drives the communication tower 6 to move upward, thereby realizing the lifting function of the communication tower 6.

As an embodiment of the present invention: the fluorescent strip is pasted on the outer surface of the indicating rod 311, in the using process, the lower supporting plate 301 is driven by the left nut seat 309 and the right nut seat 302 to move upwards, the lower supporting plate 301 drives the communication tower column 6 to move upwards, when the lower supporting plate 301 contacts the indicating rod 311, the lower supporting plate 301 drives the indicating rod 311 to move upwards in the guide sleeve 310, and after the limiting baffle 312 on the indicating rod 311 is separated from the guide sleeve 310, a driving motor circuit is cut off, so that the limiting prompt function of the lifting height is realized, and the condition that the lower supporting plate 301 is lifted and overtravel is avoided.

The basic principles and the main features of the invention and the advantages of the invention have been shown and described above, it will be evident to those skilled in the art that the invention is not limited to the details of the foregoing illustrative embodiments, but that the invention may be embodied in other specific forms without departing from the spirit or essential characteristics of the invention. The present embodiments are therefore to be considered in all respects as illustrative and not restrictive, the scope of the invention being indicated by the appended claims rather than by the foregoing description, and all changes which come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein.

Furthermore, it should be understood that although the present description refers to embodiments, not every embodiment may contain only a single embodiment, and such description is for clarity only, and those skilled in the art should integrate the description, and the embodiments may be combined as appropriate to form other embodiments understood by those skilled in the art.

Claims

1. The utility model provides an electronic communication tower, includes backup pad (2), chassis (4), communication wire (5) and communication tower (6), its characterized in that: the automatic cleaning device is characterized in that the upper support plate (2) is welded on the upper side face of the bottom frame (4), the automatic cleaning mechanism (1) is arranged on the left side of the upper end face of the upper support plate (2), the lifting mechanism (3) is installed in the bottom frame (4), the communication wire (5) is installed on the upper end face of the communication tower column (6), the communication tower column (6) is installed in the bottom frame (4), the upper end of the communication tower column (6) extends to the upper portion of the upper side face of the upper support plate (2), the automatic cleaning mechanism (1) comprises a push rod (101), a vertical plate (104), a support (105), an air spring (106) and a guide rod (112), the push rod (101) is installed in the sleeve (102), the right end face of the push rod (101) is welded with a first connecting seat (107), a first clamping plate (108) is installed in the first connecting seat (107), and the, the sleeve (102) is arranged on the upper portion of the right side face of a vertical plate (104), a return spring (103) is welded on the left end face in the sleeve (102), the right end of the return spring (103) is connected with the left side face of a push rod (101) in a welding manner, the vertical plate (104) is arranged on the left side of the upper end face of an upper supporting plate (2), a support (105) is welded on the lower side of the right end face of the vertical plate (104), a gas spring (106) is arranged in the support (105), the right end of the gas spring (106) is welded with a second connecting seat (115), a second clamping plate (114) is arranged in the second connecting seat (115), the right end face of the second clamping plate (114) is welded on the lower portion of the outer arc-shaped side face of a clamping plate (109), the push rod (101) is arranged in the middle of the clamping plate (109), a cleaning cotton pad (111) is arranged on the right end face of the push rod (101, the right end of the return spring (110) is connected with the outer arc surface of the clamping plate (109) in a welding mode.

2. An electronic communication tower according to claim 1, wherein: the clamping plate I (108) is rotatably connected with the connecting seat I (107) through a rotating shaft I, the clamping plate II (114) is rotatably connected with the connecting seat II (115) through a rotating shaft II, the support (105) is rotatably connected with the gas spring (106) through a rotating shaft III, the cross section of the clamping plate (109) is semicircular, in the using process, the communication tower column (6) extrudes the clamping plate (109), the clamping plate (109) extrudes the ejector rod (101), the ejector rod (101) moves leftwards in the sleeve (102) and compresses the return spring (103), meanwhile, the clamping plate I (108) rotates in the connecting seat I (107) through the rotating shaft I, the clamping plate II (114) rotates in the connecting seat II (115) through the rotating shaft II, meanwhile, the gas spring (106) contracts, the left side of the gas spring (106) rotates in the support (105) through the rotating shaft III, and the gas spring (106) and the return spring (103, make splint (109) and communication tower post (6) surface laminating to make splint (109) and communication tower post (6) closely laminate, improved the clear cleanliness factor in later stage.

3. An electronic communication tower according to claim 1, wherein: the cross section of the cleaning cotton pad (111) is arc-shaped, the guide rod (112) is arranged in the guide hole, the guide hole is arranged in the middle of the clamping plate (109), in the use, clean cotton pad (111) of communication tower post (6) extrusion, clean cotton pad (111) drive guide bar (112) and move in the guiding hole, guide bar (112) remove and drive connecting plate (113) and remove, connecting plate (113) remove tensile reset spring (110), reset spring (110) are under the resilience effect, with clean cotton pad (111) and the laminating of communication tower post (6) surface mutually, communication tower post (6) remove, make clean cotton pad (111) remove for communication tower post (6), the dirty of adhesion is clear away on clean cotton pad (111) to communication tower post (6), thereby the self-cleaning function of communication tower post (6) has been realized, clean effect is good.

4. An electronic communication tower according to claim 1, wherein: automatic cleaning mechanism (1) is equipped with two sets ofly, two sets of automatic cleaning mechanism (1) bilateral symmetry installs on backup pad (2) up end, and two sets of automatic cleaning mechanism (1) structures are the same, and in the use, communication tower (6) remove, make two sets of clean cotton pads (111) clear away the dirty on communication tower (6) simultaneously, have improved dirty clear range greatly, and clean wide range.

5. An electronic communication tower according to claim 1, wherein: the lifting mechanism (3) comprises a lower supporting plate (301), a right nut seat (302), a right longitudinal screw rod (303), a right groove (304), a right belt wheel (305), a left belt wheel (306), a left groove (307), a left longitudinal screw rod (308), a left nut seat (309), a guide sleeve (310), an indicating rod (311) and a limit baffle (312), wherein the lower supporting plate (301) is installed in the bottom frame (4), the upper end surface of the lower supporting plate (301) is fixedly connected with the communication tower column (6) through a bolt, the right nut seat (302) is welded on the right end surface of the lower supporting plate (301), the right end of the right nut seat (302) is installed on the right longitudinal screw rod (303), the right longitudinal screw rod (303) is installed in the middle of the right groove (304), the right groove (304) is arranged on the right side surface of the bottom frame (4), the right belt wheel (305) is sleeved on the lower part of the annular side surface of the right longitudinal screw rod, the left belt wheel (306) is sleeved on the lower portion of the annular side face of a left longitudinal screw rod (308), the left nut seat (309) is welded on the left end face of a lower supporting plate (301), the left end of the left nut seat (309) is connected with the left longitudinal screw rod (308), the left longitudinal screw rod (308) is installed in a left groove (307), the left groove (307) is formed in the left side face of an underframe (4), a guide sleeve (310) is installed on an upper supporting plate (2), an indicating rod (311) is installed in the guide sleeve (310), and a limit baffle (312) is welded on the upper end face of the indicating rod (311).

6. An electronic communication tower according to claim 5, wherein: the right nut seat (302) is connected with a right longitudinal screw rod (303) through a ball nut pair I, the left nut seat (309) is connected with a left longitudinal screw rod (308) through a ball nut pair II, the right belt wheel (305) is connected with a left belt wheel (306) through a synchronous belt, the lower end of the left longitudinal screw rod (308) is connected with a driving motor, the driving motor is installed in a containing groove, the containing groove is formed in the left side of the lower end face of the underframe (4), the driving motor is connected with an external power supply through a connecting wire, in the using process, a driving motor circuit is switched on, the driving motor drives the left longitudinal screw rod (308) to rotate in a left groove (307), the left longitudinal screw rod (308) rotates to drive the left belt wheel (306) to rotate, the left belt wheel (306) drives the right belt wheel (305) to rotate through the synchronous belt, and the right belt wheel (305) rotates to drive the, the first ball nut pair and the second ball nut pair convert the rotary motion of the right longitudinal screw rod (303) and the left longitudinal screw rod (308) into linear motion, the left nut seat (309) and the right nut seat (302) drive the lower support plate (301) to move upwards, and the lower support plate (301) drives the communication tower column (6) to move upwards, so that the lifting function of the communication tower column (6) is realized.

7. An electronic communication tower according to claim 5, wherein: the fluorescent strip is pasted on the outer surface of the indicating rod (311), in the using process, the lower supporting plate (301) is driven to move upwards by the left nut seat (309) and the right nut seat (302), the lower supporting plate (301) drives the communication tower column (6) to move upwards, when the lower supporting plate (301) contacts the indicating rod (311), the lower supporting plate (301) drives the indicating rod (311) to move upwards in the guide sleeve (310), and after the limiting baffle plate (312) on the indicating rod (311) is separated from the guide sleeve (310), a driving motor circuit is cut off, so that the limiting prompting function of the lifting height is realized, and the condition that the lower supporting plate (301) is lifted to exceed the stroke is avoided.