CN115076346A

CN115076346A - Lubricating equipment for aluminum ingot mould conveying chain

Info

Publication number: CN115076346A
Application number: CN202210708781.4A
Authority: CN
Inventors: 王启; 王赟; 张敬龙; 谢菊; 陈冠吉
Original assignee: Guangdong Shunbo Aluminum Alloy Co ltd
Current assignee: Guangdong Shunbo Aluminum Alloy Co ltd
Priority date: 2022-06-21
Filing date: 2022-06-21
Publication date: 2022-09-20

Abstract

The invention provides lubricating equipment for an aluminum ingot mould conveying chain, which comprises a spraying lubricating device and a transmission lubricating device, wherein the spraying lubricating device is used for spraying and lubricating the conveying chain, and the transmission lubricating device is connected with the conveying chain to realize contact lubrication; the transmission lubricating device comprises a bearing groove and a gear lubricating structure, the gear lubricating structure is rotatably arranged between two end faces of the bearing groove, the conveying chain is in meshing transmission with the gear lubricating structure, a spray head of the spray lubricating device is positioned above the gear lubricating structure and is used for spraying and lubricating a chain in meshing transmission with the gear lubricating structure, the bearing groove is used for bearing and storing spray dripping lubricating oil, and the gear lubricating structure transfers and paints the lubricating oil in the bearing groove to the conveying chain; the novel structure can be conveniently additionally arranged on old equipment, automatically and effectively lubricate the conveying chain, manual operation is not needed, the lubricating efficiency and quality can be effectively improved, and the risk of manual operation is reduced.

Description

Lubricating equipment for aluminum ingot mould conveying chain

Technical Field

The invention relates to the field of conveying chain lubricating equipment, in particular to lubricating equipment for an aluminum ingot mold conveying chain.

Background

In the working process of the casting machine, due to continuous casting, the mold can keep a certain temperature (200 ℃ and 300 ℃), and the temperature of the chain driving the mold can be increased along with the temperature. Because of higher temperature, the lubricating substance can be gradually evaporated, so that the rotating performance of the rotating wheel bearing of the chain is reduced; after the rotation performance of the rotating wheel is reduced, the rotating wheel is locked, the stable movement of the mold is influenced, and the fluctuation occurs in the solidification process of the aluminum ingot to generate a product with unqualified appearance; traditional ingot casting production line, especially to old equipment relatively, the rectification degree of difficulty is great, and the cost is very high, and most processing methods are for manually scribbling lubricating oil, and efficiency is not high to manual operation has certain risk, so remain to improve.

Disclosure of Invention

In order to overcome the defects of the prior art, the invention aims to provide the lubricating equipment for the aluminum ingot mould conveying chain, which has a novel structure, can be conveniently additionally arranged on old equipment, automatically and effectively lubricate the conveying chain, does not need manual operation, can effectively improve the lubricating efficiency and quality, and reduces the risk of manual operation.

In order to achieve the purpose, the invention adopts the following technical scheme:

the invention provides lubricating equipment for an aluminum ingot mould conveying chain, which comprises a spraying lubricating device and a transmission lubricating device, wherein the spraying lubricating device is used for spraying and lubricating the conveying chain, and the transmission lubricating device is connected with the conveying chain to realize contact lubrication;

the transmission lubricating device comprises a receiving groove and a gear lubricating structure, the gear lubricating structure is rotatably installed between two end faces of the receiving groove, the conveying chain is in meshing transmission with the gear lubricating structure, a spray head of the spray lubricating device is located above the gear lubricating structure and used for spraying and lubricating a chain in meshing transmission with the gear lubricating structure, the receiving groove is used for receiving and storing spray dripping lubricating oil, and the gear lubricating structure transfers and paints the lubricating oil in the receiving groove to the conveying chain.

In a preferred technical scheme of the invention, the gear lubricating structure comprises a gear body and a plurality of teeth fixedly arranged on the outer wall of the gear body, wherein an oil coating mechanism is arranged at the teeth and used for adsorbing lubricating oil in the bearing groove and transferring and coating the lubricating oil on the contacted conveying chain.

In a preferred technical scheme of the invention, the end surface of the tooth, which is far away from the wheel body, is recessed downwards to form a clamping groove, one side wall of the clamping groove is provided with a first counter bore, the other side of the clamping groove is provided with a first through hole, and the first through hole is superposed with the axis of the first counter bore; the oiling mechanism comprises a sponge block, a pushing and pressing piece, a spring and a guide rod, the pushing and pressing piece is installed in the clamping groove, a pressing block of the pushing and pressing piece protrudes out of the clamping groove through a first through hole, a convex column is fixedly arranged at one end of the guide rod, a thread is arranged on the outer wall of the convex column and is connected and installed at a first countersunk hole in a threaded manner, the other end of the guide rod is movably inserted into the pushing and pressing piece, the spring is sleeved on the guide rod, and the spring provides outward thrust for the pushing and pressing piece; the sponge piece is arranged in the clamping groove, the sponge piece is clamped between the pushing piece and the inner wall of the clamping groove, and when the pushing piece is pressed from the outside, the pushing piece extrudes the sponge piece, so that lubricating oil in the sponge piece flows out.

In a preferred technical scheme of the invention, one side of the top of the clamping groove is provided with a flow guide groove, the bottom of the flow guide groove is obliquely arranged, the top end of the flow guide groove is communicated with the clamping groove, the bottom end of the flow guide groove extends to the side wall of the tooth, and the oblique bottom end of the bottom of the flow guide groove is positioned above the pressing block.

In a preferred technical scheme of the invention, a bump is fixedly arranged on one side of the top of the clamping groove, which is far away from the first through hole, and the bottom of the bump extends to the upper part of the top of the clamping groove and is used for limiting the sponge block; the clamping groove is far away from the wall surface of the first through hole, and an oil spoon groove is formed in the wall surface of the first through hole and communicated with the clamping groove through a backflow hole.

In a preferred technical scheme of the invention, the upper wall surface and the lower wall surface of the oil scoop groove are both of inclined surface structures, and the two inclined surfaces form a narrowing structure at the notch of the oil scoop groove.

In a preferred technical scheme of the invention, the backflow hole is of a bending structure, the bending part is arranged towards one side far away from the clamping groove, and the bending part is flush with the plane where the notch of the clamping groove is located; the backward flow hole includes first slope section and second slope section, and the slope top of first slope section and the inclined plane bottom position intercommunication that the spoon oil groove is close to the draw-in groove, the slope bottom and the draw-in groove intercommunication of second slope section, the slope bottom of first slope section and the slope top of second slope section be linked together, form the portion of bending.

Drawings

FIG. 1 is a schematic structural diagram of a lubricating apparatus for an aluminum ingot mold conveying chain provided in an embodiment of the present invention;

FIG. 2 is a schematic diagram of a transmission lubrication apparatus and a transmission chain according to an embodiment of the present invention;

FIG. 3 is a schematic view of the internal structure of a gear lubrication structure provided in an embodiment of the present invention;

FIG. 4 is a schematic view of a tooth construction provided in an exemplary embodiment of the present invention;

FIG. 5 is a schematic view of the mating structure of a tooth and an oiling mechanism provided in an exemplary embodiment of the present invention;

FIG. 6 is a schematic view of a pusher provided in an embodiment of the present invention;

FIG. 7 is a schematic illustration of the scoop condition of the oiling mechanism provided in an exemplary embodiment of the present invention;

FIG. 8 is a schematic view of a first angular position of the oil applying mechanism after the scoop oil has been swung upwardly in accordance with an exemplary embodiment of the present invention;

FIG. 9 is a schematic diagram of a second angular position of the oil applying mechanism after the oil scoop has been swung upwardly in accordance with an exemplary embodiment of the present invention;

fig. 10 is a schematic diagram of a third angular position of the oil applying mechanism according to an embodiment of the present invention, after the oil scoop swings upward.

In the figure:

100. a spray lubrication device; 110. a spray head; 120. a pump body; 130. an oil storage tank; 140. a first oil delivery pipe; 150. a second oil delivery pipe; 160. a third oil delivery pipe; 200. a transmission lubrication device; 210. a receiving groove; 211. a discharge pipe; 220. a gear lubrication structure; 221. a wheel body; 222. teeth; 223. a card slot; 224. a first counterbore; 225. a first perforation; 226. a diversion trench; 227. a bump; 228. an oil scoop groove; 229. a return orifice; 2291. a first inclined section; 2292. a second inclined section; 300. an oiling mechanism; 310. a sponge block; 320. a biasing member; 321. briquetting; 322. a push block; 323. a first male pipe; 324. a second male pipe; 325. a first guide hole; 326. a second guide hole; 327. sinking a groove; 330. a spring; 340. a guide bar; 341. a convex column.

Detailed Description

The technical scheme of the invention is further explained by the specific implementation mode in combination with the attached drawings.

As shown in fig. 1 and fig. 2, the embodiment of the invention discloses a lubricating device for an aluminum ingot mold conveying chain, which comprises a spray lubricating device 100 and a transmission lubricating device 200, wherein the spray lubricating device 100 is used for spraying and lubricating the conveying chain, and the transmission lubricating device 200 is connected with the conveying chain in a transmission manner to realize contact lubrication; the transmission lubricating device 200 comprises a receiving groove 210 and a gear lubricating structure 220, the gear lubricating structure 220 is rotatably installed between two end faces of the receiving groove 210, a conveying chain is in meshed transmission with the gear lubricating structure 220, a spray head 110 of the spray lubricating device 100 is positioned above the gear lubricating structure 220 and is used for spraying and lubricating a chain in meshed transmission with the gear lubricating structure 220, the receiving groove 210 is used for receiving and storing spray dripping lubricating oil, and the gear lubricating structure 220 transfers and paints the lubricating oil in the receiving groove 210 to the conveying chain.

Furthermore, the bottom of the receiving groove 210 is communicated with a discharge pipe 211, and the discharge pipe is provided with a switch valve for discharging the lubricating oil in the receiving groove, so that the lubricating oil can be conveniently replaced.

Further, the spray lubrication device 100 includes a pump body 120, an oil storage tank 130, a first oil delivery pipe 140, a second oil delivery pipe 150, a third oil delivery pipe 160, and a nozzle 110, wherein an oil inlet of the pump body is communicated with an oil outlet of the oil storage tank through the first oil delivery pipe, the first oil delivery pipe is provided with an electromagnetic valve, the oil outlet of the pump body is communicated with the second oil delivery pipe, two third oil delivery pipes are arranged at the end part of the second oil delivery pipe through a three-way pipe, the third oil delivery pipes are respectively arranged in parallel with the two conveying chains, the two third oil delivery pipes are respectively located above the corresponding conveying chains, and the nozzle is installed at the bottom of the third oil delivery pipe and sprays lubricating oil to the conveying chains.

Further, the length of the receiving groove 210 is larger than the interval between the two conveying chains, and the sprayed and dropped lubricating oil can be received and contained in the receiving groove; the number of the gear lubricating structures 220 is 2, the gear lubricating structures are respectively arranged corresponding to the two conveying chains, and the two gear lubricating structures are arranged in the receiving groove and utilize lubricating oil in the receiving groove.

The lubricating device for the aluminum ingot mould conveying chain is novel in structure, can automatically and effectively lubricate the aluminum ingot mould conveying chain, sprays and lubricates the conveying chain through the spraying and lubricating device, paints and lubricates the conveying chain through the transmission and lubricating device, and achieves double lubricating effects; moreover, the transmission lubricating device is provided with a receiving groove, so that the lubricating oil sprayed or dropped in the use process of the spray lubricating device can be received and collected, and the waste of the lubricating oil is effectively prevented; moreover, the conveying chain of the existing equipment can be conveniently and additionally arranged by the aid of the structural design, the conveying chain is convenient to use, the original equipment is not required to be disassembled and assembled, installation difficulty is reduced, and popularization and use are facilitated.

Further, as shown in fig. 3, the gear lubrication structure 220 includes a wheel body 221 and a plurality of teeth 222 fixedly disposed on an outer wall of the wheel body 221, a rotating shaft is fixedly disposed in the middle of the wheel body, and the gear lubrication structure is erected between two end surfaces of the receiving groove through a bearing seat transmission frame, so that the gear lubrication structure and the conveying chain are in meshing transmission; the oiling mechanism 300 is installed at the tooth 222, and the oiling mechanism 300 is used for adsorbing the lubricating oil in the receiving groove 210 and transferring and coating the lubricating oil on the contacted conveying chain; when the teeth rotate to the bottom of the receiving groove, the lubricating oil in the receiving groove can be adsorbed by the oil coating mechanism, and when the teeth rotate to the part meshed with the conveying chain, the lubricating oil can flow out and contact with the conveying chain, so that the lubricating effect is realized.

Further, as shown in fig. 4 and 5, a clamping groove 223 is recessed downward from an end surface of the tooth 222 away from the wheel body 221, a first counter bore 224 is formed in a side wall of the clamping groove 223, a first through hole 225 is formed in the other side of the clamping groove, and an axis of the first through hole 225 coincides with an axis of the first counter bore 224; the oiling mechanism 300 comprises a sponge block 310, a pushing piece 320, a spring 330 and a guide rod 340, wherein the pushing piece 320 is installed in a clamping groove 223, a pressing block 321 of the pushing piece 320 protrudes out of the clamping groove 223 through a first through hole 225, one end of the guide rod 340 is fixedly provided with a convex column 341, the outer wall of the convex column 341 is provided with threads, the convex column is connected and installed at a first countersunk hole 224 through the threads, the other end of the guide rod 340 is movably inserted into the pushing piece 320, the spring 330 is sleeved on the guide rod 340, and the spring 330 provides outward thrust for the pushing piece 320; the sponge block 310 is arranged in the clamping groove 223, the sponge block 310 is clamped between the pushing piece 320 and the inner wall of the clamping groove 223, and when the pushing piece 320 is pressed from the outside, the pushing piece 320 extrudes the sponge block 310 to enable lubricating oil in the sponge block 310 to flow out.

Wherein, the briquetting that bulldozes the piece is located conveying chain upstream one side, and when conveying chain and tooth meshing transmission, the pivot position of conveying chain can form the application of force extrusion to the briquetting to cause the extrusion to the sponge piece, the lubricating oil in the sponge piece flows out, and lubricating oil adheres to on the pivot, and follow-up transfer to on the rotating gear.

Further, as shown in fig. 6, the pushing element 320 includes a pushing block 322 and a pressing block 321, a first convex tube 323 is fixedly disposed on a side wall of the pushing block 322, and an outer diameter of the first convex tube is adapted to an outer diameter of the first through hole; a second convex pipe 324 is fixedly arranged on one side wall of the pressing block 321, and the outer diameter of the second convex pipe is matched with the inner diameter of the first convex pipe and is in threaded connection and matching; first guiding hole 325 has been seted up to the lateral wall of ejector pad 322, first guiding hole runs through the both sides of ejector pad, and the axis coincidence of the axis of first guiding hole and first protruding pipe, the terminal surface of briquetting 321 is equipped with second guiding hole 326, the axis coincidence of the axis of second guiding hole and second protruding pipe, the diameter of first guiding hole and second guiding hole is the same, and all with the external diameter adaptation of guide bar, the tip of guide bar can run through first guiding hole, stretch into in the second guiding hole, thereby provide the direction effect for the removal that bulldozes the piece, conveniently bulldoze the removal and reset of piece.

Furthermore, the end of the first guide hole 325 away from the first convex tube 323 is provided with a sinking groove 327, the diameter of the sinking groove is matched with the outer diameter of the spring, one end of the spring is clamped in the sinking groove, and the inner diameter of the spring is matched with the diameter of the guide rod, so that the spring can be further prevented from being separated.

Furthermore, the outer wall of the first convex pipe is of a square structure, the first through hole is of a square hole structure, and the first convex pipe is in sliding fit with the first through hole, so that the push block can be effectively prevented from rotating and deviating, and the sponge block can be effectively extruded; it should be noted that, the outer wall of the pressing block is of a cylindrical structure, which does not affect the normal rotation of the pressing block and facilitates the disassembly and assembly between the first convex pipe and the second convex pipe.

Furthermore, a second through hole is formed in the sponge block, the space of the second through hole is matched with the outer diameter of the spring, a crack is formed in the bottom of the sponge block, the crack extends upwards to be communicated with the second through hole, and two ends of the crack penetrate through two side walls of the sponge block; the sponge body can be conveniently and smoothly inserted and installed.

When the oiling mechanism is installed, the pushing block is placed in the clamping groove, and the first convex pipe extends into the first through hole; then, a spring is placed into the clamping groove, and one end of the spring extends into the sinking groove and is clamped in the sinking groove; then the guide rod is inserted into the first countersunk hole and is screwed down, so that the spring and the push block are clamped and installed in the clamping groove; then, the pressing block is arranged at the first perforation, so that the second convex pipe is in threaded connection and matching with the first convex pipe; and finally, placing the sponge block into the clamping groove, so that the sponge block is clamped inside the clamping groove, and installing the oiling mechanism.

Furthermore, the end part of the pressing block, which is far away from the second convex pipe, is of a convex spherical crown structure, can be conveniently contacted with a shaft pin of the conveying chain and can apply pressure, and the pressing piece can be conveniently moved and can extrude the sponge block.

Furthermore, the middle part of the end face of the convex column far away from the guide rod and the middle part of the end face of the pressing block far away from the second convex tube are both provided with prismatic grooves for being matched with an external screwdriver tool for use, so that the guide column and the pressing piece are convenient to disassemble and assemble for use.

Furthermore, the wall surface of the push block, which is far away from the first convex pipe, is of an inclined surface structure, and the bottom of the push block extends and inclines towards one side, which is far away from the first convex pipe, so that the part, which is close to the bottom of the clamping groove, of the sponge block can be narrowed, and the sponge block can be conveniently inserted; on the other hand, the contact area of the push block and the sponge block can be increased, and the outflow of lubricating oil can be accelerated in the subsequent extrusion process.

Furthermore, a diversion trench 226 is arranged on one side of the top of the clamping groove 223, the bottom of the diversion trench 226 is obliquely arranged, the top end of the diversion trench 226 is communicated with the clamping groove 223, the bottom end of the diversion trench 226 extends to the side wall of the tooth 222, and the oblique bottom end of the bottom of the diversion trench 226 is positioned above the pressing block 321; the guide groove can provide a flowing flow channel for the lubricating oil, so that the lubricating oil can flow out along the guide groove, and the lubricating oil can be smoothly contacted and lubricated with the shaft pin part of the conveying chain.

Furthermore, a projection 227 is fixedly arranged on one side of the top of the clamping groove 223 far away from the first through hole 225, and the bottom of the projection 227 extends to the position above the top of the clamping groove 223 to limit the sponge block 310, so that the sponge block is further prevented from being separated; an oil scoop groove 228 is formed in the wall surface of the clamping groove 223 far away from the first through hole 225, and the oil scoop groove 228 is communicated with the clamping groove 223 through a backflow hole 229.

Furtherly, the bottom of accepting the groove is arc column structure for lubricating oil gathers towards bottom position, and when gear lubrication structure rotated, the spoon oil groove of the tooth that is in the bottom position can carry out spoon oil, drives partial lubricating oil and rotates, and when rotating to the top, makes the lubricating oil flow to sponge piece department.

Further, the upper and lower wall surfaces of the oil scoop groove 228 are both inclined surface structures, and the two inclined surfaces form a narrowing structure at the notch of the oil scoop groove 228; due to the arrangement of the two inclined planes, on one hand, external lubricating oil can conveniently and smoothly enter the oil groove of the spoon, and especially when the tooth teeth rotate to the bottom of the bearing groove, the lubricating oil enters the oil groove of the spoon along the inclined planes; on the other hand, the lubricating oil can be prevented from flowing out of the notch of the oil groove of the spoon, especially when the teeth rotate to the top position, the lubricating oil can still flow towards the bottom direction of the other inclined plane, and flows back towards the sponge block through the backflow hole.

Further, the reflow hole 229 is of a bending structure, and the bending portion is disposed towards a side far away from the card slot 223, and the bending portion is flush with a plane where the notch of the card slot is located; the return hole 229 includes a first inclined section 2291 and a second inclined section 2292, the inclined top end of the first inclined section 2291 is communicated with the inclined bottom end of the oil scoop groove 228 close to the clamping groove, the inclined bottom end of the second inclined section 2292 is communicated with the clamping groove 223, and the inclined bottom end of the first inclined section 2291 is communicated with the inclined top end of the second inclined section 2292 to form a bending part.

As shown in fig. 7 to 10, tooth is through accepting the bottom back in groove, in the in-process of up swing, the inside lubricating oil of spoon oil groove can not be easy get into in the draw-in groove, wait tooth swing to when being close to the top position, the lubricating oil in the spoon oil groove just can flow through the portion of bending and get into in the draw-in groove, especially swing to directly over at the tooth, in contact with the conveying chain, the inside whole lubricating oil of spoon oil groove just can flow in the draw-in groove of station, because sponge piece self adsorbs full lubricating oil, when the lubricating oil in the spoon oil groove flows to the sponge piece, can not absorb easily, the conveying chain also can extrude the briquetting this moment, make lubricating oil flow along the guiding gutter, thereby make the pivot of conveying chain obtain to contact more lubricating oil, realize effectual lubrication effect.

While the invention has been described with reference to a preferred embodiment, it will be understood by those skilled in the art that various changes may be made and equivalents may be substituted for elements thereof without departing from the spirit and scope of the invention. The present invention is not to be limited by the specific embodiments disclosed herein, and other embodiments that fall within the scope of the claims of the present application are intended to be within the scope of the present invention.

Claims

1. The utility model provides a lubricating arrangement for aluminium ingot mould conveying chain which characterized in that:

the spraying lubricating device is used for spraying and lubricating the conveying chain, and the transmission lubricating device is connected with the conveying chain to realize contact lubrication;

2. The lubricating apparatus for the aluminum ingot mold conveying chain as claimed in claim 1, wherein:

the gear lubricating structure comprises a gear body and a plurality of teeth fixedly arranged on the outer wall of the gear body, wherein an oiling mechanism is arranged at the teeth and used for adsorbing lubricating oil in the bearing groove and transferring the lubricating oil to the conveying chain contacted with the lubricating oil.

3. The lubricating apparatus for the aluminum ingot mold conveying chain as claimed in claim 2, wherein:

the end face, away from the wheel body, of the tooth is provided with a clamping groove in a downward recessed mode, a first counter bore is formed in one side wall of the clamping groove, a first through hole is formed in the other side of the clamping groove, and the first through hole is overlapped with the axis of the first counter bore;

the oiling mechanism comprises a sponge block, a pushing and pressing piece, a spring and a guide rod, the pushing and pressing piece is installed in the clamping groove, a pressing block of the pushing and pressing piece protrudes out of the clamping groove through a first through hole, a convex column is fixedly arranged at one end of the guide rod, the outer wall of the convex column is provided with threads, the convex column is connected and installed at a first countersunk hole, the other end of the guide rod is movably inserted into the pushing and pressing piece, the spring is sleeved on the guide rod, and the spring provides outward thrust for the pushing and pressing piece;

the sponge piece is arranged in the clamping groove, the sponge piece is clamped between the pushing piece and the inner wall of the clamping groove, and when the pushing piece is pressed from the outside, the pushing piece extrudes the sponge piece, so that lubricating oil in the sponge piece flows out.

4. A lubricating apparatus for an aluminium ingot mould conveying chain according to claim 3, characterised in that:

draw-in groove top one side is equipped with the guiding gutter, and the tank bottom slope of guiding gutter sets up, and the top and the draw-in groove intercommunication of guiding gutter, bottom extend to the lateral wall of tooth, and the tank bottom slope bottom of guiding gutter is located the top of briquetting.

5. A lubricating apparatus for an aluminium ingot mould conveying chain according to claim 4, characterized in that:

a convex block is fixedly arranged on one side, away from the first through hole, of the top of the clamping groove, and the bottom of the convex block extends to the position above the top of the clamping groove and is used for limiting the sponge block; the clamping groove is far away from the wall surface of the first through hole, and an oil spoon groove is formed in the wall surface of the first through hole and communicated with the clamping groove through a backflow hole.

6. A lubricating apparatus for an aluminium ingot mould conveying chain according to claim 5, characterized in that:

the upper wall surface and the lower wall surface of the oil spoon groove are both of inclined surface structures, and the two inclined surfaces form a narrowing structure at the notch of the oil spoon groove.

7. A lubricating apparatus for an aluminium ingot mould conveying chain according to claim 6, characterised in that:

the backflow hole is of a bending structure, the bending part is arranged towards one side far away from the clamping groove, and the bending part is flush with the plane where the notch of the clamping groove is located;

the backward flow hole includes first slope section and second slope section, and the slope top of first slope section and the inclined plane bottom position intercommunication that the spoon oil groove is close to the draw-in groove, the slope bottom and the draw-in groove intercommunication of second slope section, the slope bottom of first slope section and the slope top of second slope section be linked together, form the portion of bending.