CN206225768U - A kind of cam pin module - Google Patents

Abstract

The utility model discloses a kind of cam pin module, cam, motor, main shaft, driving wheel and cutter mechanism are promoted including contact pin mechanism, contact pin, contact pin promotes cam and driving wheel to be installed on main shaft, driving wheel is connected with leverage, cutter mechanism also connects the leverage, contact pin promotes cam to connect driving plate by unloading force mechanisms, and contact pin mechanism also connects driving plate, and cutter mechanism is docked with contact pin mechanism；Driving plate is installed on a pair of slide rails, is unloaded force mechanisms and is unloaded power base including one group of Cam Follower and one, and Cam Follower promotes cam and catch bar to dock with contact pin respectively on one side, and catch bar is fixed in driving plate.The utility model promotes actuated by cams contact pin using typical circular wheel drive cut end of nonplanar structure and using contact pin, the drawbacks of avoiding conventionally employed multiple contact pins and promote actuated by cams to exist, by equipment cost reduction about 1/3rd, contact pin speed improves more than 30%, and contact pin precision, stability and service life are highly improved.

Description

A kind of cam pin module

Technical field

The utility model is related to electron trade technical field of processing equipment, more particularly to a kind of cam of connector pin to insert Pin equipment.

Background technology

Largely popularized with electronic product and fast-developing, for the need for the electronics connection member between electronic product Ask also increasing.The pedestal of electronics connection member is general to be molded with plastic-injection, i.e. HOUSING（Plastic casing）, in plastic casing Main body on be provided with circular hole for plugging terminal.Terminal is plugged, most traditional mode is manually by terminal One by one in insertion circular hole.Later, people carried out insertion terminal work using pin machine.The processing rotating speed of traditional pin machine is generally only 300 ~ 400 turns per minute can be reached, production efficiency is low.

And developing rapidly with electronic product, and most of electronic products all towards it is smaller, more closely direction develop, This allows for people and is proposed requirement higher to the miniaturization of bonder terminal, densification, and obviously tradition pin machine The process requirements of people cannot have been met.High-Speed Automatic cam pin machine is occurred in that with that, and general principle is by motor band Moving cam completes contact pin as power, and the patent of invention of such as Patent No. ZL 201310310304.3 discloses a kind of high speed Cam pin machine, which employs three sets of structures of cam, i.e. clamping and positioning and cuts using actuated by cams, itself the disadvantage is that, First, the making of cam is far more precise, and three sets of cams need cost higher, and its control structure is also more complicated, and precision is relatively low； Second, because cam quantity is excessive, cause speed still not fast enough, constrain the efficiency of contact pin；3rd, in equipment running process Less stable, this can also influence contact pin effect.

Utility model content

The technical problems to be solved in the utility model be to provide a kind of structure design more rationally, contact pin speed is fast, coordinate essence The cam pin module that degree is high, integrated cost is lower.

In order to solve the above technical problems, the utility model is adopted the following technical scheme that：A kind of cam pin module, including insert Pin mechanism and contact pin promote cam, it is characterised in that：Motor, main shaft, driving wheel and cutter mechanism are also included, main shaft is by connection Axle device connects motor, and contact pin promotes cam and driving wheel to be installed on main shaft and forms coaxial fixed, and driving wheel is connected with Lever machine Structure, cutter mechanism also connects the leverage, and contact pin promotes cam to unload force mechanisms by one and connects a driving plate, contact pin mechanism Also it is connected with the driving plate, cutter mechanism is docked with contact pin mechanism；The driving plate is installed on a pair of slide rails, the power of the unloading machine Structure include one group of Cam Follower and one it is swingable unload power base, Cam Follower is fixed on and unloads on power base, cam following Device with contact pin while promote cam to dock, another side is docked with a catch bar, and catch bar is fixed in driving plate, driving plate is connected There is resetting means；Cam is promoted to promote Cam Follower to be swung together with power base is unloaded by contact pin, Cam Follower drives Catch bar is moved, thus drive driving plate advance so that promote contact pin mechanism advance complete spigot child-operation, driving plate by Resetting means drives and resets, and is consequently formed reciprocal.

Further, the main shaft is fixed in a lower plate by bearing block, and foreboard, back plate, side are provided with lower plate Contact pin is promoted cam, driving wheel, leverage and unloaded including force mechanisms enclose and cover by plate and upper plate, above-mentioned each plate, contact pin mechanism and Cutter mechanism is exposed to outside side plate；The slide rail is installed in back plate.

Further, the driving wheel include upper driving wheel and lower driving wheel, the leverage include upper lever and Lower lever, cutter mechanism includes upper cutter and lower cutter；The lower lower lever of driving wheel connection, lower lever front end connects a lower cutter Slide, lower cutter slide is connected with lower cutter fixed seat, and lower cutter is installed in lower cutter fixed seat, and terminal is located at lower cutter On, the plastic casing for receiving terminal（HOUSING）Positioned at terminal opposite, fixed by special fixed mechanism, terminal is then by special The manipulator that door is equipped with（Certainly manually can also）Deliver to terminal and place position；Upper driving wheel connects upper lever, and upper lever front end connects A upper cutter slide is connect, upper cutter is fixed by upper cutter slide；Upper cutter slide and lower cutter slide connect with contact pin mechanism Connect.

Further, lower lever and upper lever have identical structure, include forearm and postbrachium, forearm and postbrachium it Between form structure straggly up and down, and both are connected as a single entity by axle sleeve, and forearm front portion is provided with roller bearing, postbrachium rear portion be provided with driving wheel with Driving wheel, driving wheel is docked with wheel with driving wheel；Upper lever and lower lever are fixed on foreboard and back plate each via a guide shaft activity Between form lever construction.

Further, upper cutter slide has a chute, and the anterior roller bearing of upper lever is stuck in the chute of upper cutter slide Form upper cutter structure movable up and down；Lower cutter slide also has a chute, and the anterior roller bearing of lower lever is stuck in lower cutter Lower cutter is formed in the chute of slide to can slide up and down structure.

Further, the upper driving wheel and lower driving wheel have identical structure, and its sheave surface is non-planar junction Structure, but the thickness of wheel disc is uniform, and upper convex portion and lower concave part are respectively provided with thereon, and upper convex portion and lower concave part are alternateed, the table of wheel disc Face is to seamlessly transit；Upper driving wheel and lower driving wheel are staggered；The driving wheel supporting roller is parallel to be provided with two, upper driving wheel Wheel disc be stuck between two driving wheel supporting rollers of upper lever, and the wheel disc of lower driving wheel is then stuck in two of lower lever drivings Between wheel supporting roller；By the swing rotation of upper driving wheel and lower driving wheel through driving wheel supporting roller be converted into upper lever and under The rocking action of lever is driving moving up and down for upper cutter and lower cutter.

Further, the Cam Follower includes two rollers, is mounted on unloading the head end of power base, one of them Roller promotes cam to connect with contact pin, and another roller connects with catch bar.

Further, a fixed block is provided with lower plate, the tail end for unloading power base is installed on this and fixes by a fixing axle Swingable structure is constituted on block.

Further, fixed by a guide pin bushing respectively between upper lever and lower lever and respective guide shaft.

Preferably, the front end of main shaft is provided with optoelectronic switch, and optoelectronic switch matches near the side of main shaft with optoelectronic switch Anti-dazzling screen be then fixed on main shaft, optoelectronic switch is covered together with anti-dazzling screen by a protection board.The function of optoelectronic switch is main Have at 2 points, one is to determine（Main shaft, contact pin promote cam and driving wheel）Relative zero；Two are eliminated by way of " clear point " Motor（Servomotor）Cumulative errors in the process of running.

The present invention promotes actuated by cams by typical circular wheel drive cut end using nonplanar structure and using contact pin Contact pin, whole process fully automated can be carried out, it is to avoid the drawbacks of existing for conventionally employed multiple actuated by cams, not only by equipment Integrated cost reduction about 1/3rd, and contact pin speed is improved more than 30%, while contact pin precision is also highly improved, And improve the operation stability and service life of equipment.

Brief description of the drawings

Fig. 1 is the utility model main part structure chart；

Fig. 2 is the utility model main part Facad structure figure；

Fig. 3 is the utility model main part construction profile；

Fig. 4 is that the utility model contact pin promotes cam and contact pin mechanism assembly structure figure；

Fig. 5 is that the utility model contact pin promotes cam and contact pin mechanism setting plan；

Fig. 6 is that the utility model main shaft promotes cam assembly structure figure with upper and lower driving wheel and contact pin；

Fig. 7 is the utility model contact pin mechanism mounting structure figure；

Fig. 8 is lever construction figure；

Fig. 9 is upper and lower driving wheel and working gear process time diagram.

In figure, 1 is motor, and 2 is shaft coupling, and 3 is bearing block, and 4 is lower plate, and 5 is main shaft, and 6 is back plate, and 7 is foreboard, and 8 are Lower driving wheel, 9 is that contact pin promotes cam, and 10 is upper driving wheel, and 11 is contact pin mechanism, and 12 is driving plate, and 13 is catch bar, and 14 are Force mechanisms are unloaded, 15 is slide rail, and 16 is lower lever, and 17 is guide shaft, and 18 is lower cutter sliding seat, and 19 is fixed column, and 20 is lower cutter Fixed seat, 21 is lower cutter, and 22 is upper lever, and 23 is upper moving knife slide, and 24 is upper moving knife, and 25 is terminal, and 26 is plastic casing, 27 To unload power base, 28 is Cam Follower, and 29 is fixing axle, and 30 is fixed block, and 31 is optoelectronic switch, and 32 is anti-dazzling screen, and 33 are Postbrachium, 34 is forearm, and 35 is axle sleeve, and 36 is driving wheel supporting roller, and 37 is roller bearing, and 38 is guide pin bushing.

Specific embodiment

To enable above-mentioned purpose of the present utility model, feature and advantage more obvious understandable, below in conjunction with the accompanying drawings to this The specific embodiment of utility model is described in detail.Elaborate many details in order to abundant in the following description Understand the utility model.But the utility model can be implemented with being much different from other manner described here, this area Technical staff can do similar improvement in the case of without prejudice to the utility model intension, therefore the utility model does not receive following public affairs The limitation of the specific implementation opened.

Unless otherwise defined, all technologies used herein and scientific terminology with belong to the utility model technical field The implication that technical staff is generally understood that is identical.Term used in the utility model, such as "front", "rear", " on ", D score, "left", "right" etc., is intended merely to describe the purpose of specific embodiment, it is not intended that in limitation the utility model.

In the present embodiment, reference picture 1, Fig. 2, Fig. 3, Fig. 4 and Fig. 5, the cam pin module,

Including motor 1, main shaft 5, driving wheel, contact pin promotes cam 9, contact pin mechanism 11 and cutter mechanism, main shaft 5 to pass through Shaft coupling 2 connects motor 1, and contact pin promotes cam 9 and driving wheel to be installed on main shaft 5 and forms coaxial fixed, and driving wheel is connected with Leverage, cutter mechanism also connects leverage, and contact pin promotes cam 9 to unload force mechanisms 14 by one and connects a driving plate 12, Contact pin mechanism 11 is connected with the driving plate 12, and cutter mechanism is docked with contact pin mechanism 11；The driving plate 12 is installed on a pair of cunnings On rail 15, it is described unload force mechanisms 14 including one group of Cam Follower 28 and it is swingable unload power base 27, Cam Follower 28 It is fixed on and unloads on power base 27, the one side of Cam Follower 28 and contact pin promotes cam 9 to dock, another side and a catch bar 13 pairs Connect, catch bar 13 is fixed in driving plate 12, driving plate 12 is connected with resetting means（It is not shown）；Cam 9 is promoted by contact pin Cam Follower 28 is promoted to be swung together with power base 27 is unloaded, Cam Follower 28 drives catch bar 13 to move, thus Driving plate 12 is driven to advance, so as to promote the advance of contact pin mechanism 11 to complete insertion terminal 25 operate, driving plate 12 is by resetting means band It is dynamic to reset, it is consequently formed reciprocal.

The main shaft 5 is fixed in a lower plate 4 by bearing block 3, and foreboard 7, back plate 6, side plate are provided with lower plate 4 （It is not shown）And upper plate（Do not identify）Contact pin is promoted into cam 9, driving wheel, leverage and is unloaded including force mechanisms 14 enclose and cover, inserted Pin mechanism 11 and cutter mechanism are exposed to outside side plate；The slide rail 15 is installed in back plate 6.

Reference picture 1, Fig. 2, Fig. 6 and Fig. 7, the driving wheel includes upper driving wheel 10 and lower driving wheel 8, the leverage Upper lever 22 and lower lever 16 are included, cutter mechanism includes upper cutter 24 and lower cutter 21；It is lower to drive the lower lever of 8 wheel connections 16, the lower front end of lever 16 connects a lower cutter slide 18, and lower cutter slide 18 is connected with lower cutter fixed seat 20, and lower cutter 21 is pacified Loaded in lower cutter fixed seat 20, terminal 25 is located on lower cutter 21, the plastic casing 26 for receiving terminal 25（That is HOUSING） Positioned at the opposite of terminal 25, by special fixed mechanism（The scope of the invention is not belonging to, it is not shown）Fixed, terminal 25 is then by specially matching somebody with somebody Standby manipulator（The scope of the invention is not belonging to, it is not shown）Deliver to terminal and place position（Can certainly manually feeding）；Upper driving Wheel 10 connects upper lever 22, and the front end of upper lever 22 connects a upper cutter slide 23, and upper cutter 24 is fixed by upper cutter slide 23； Upper cutter slide 23 and lower cutter slide 18 are connected with contact pin mechanism 11.

Reference picture 1, Fig. 3 and Fig. 8, lower lever 16 and upper lever 22 have identical structure, include forearm 34 and after Arm 33, forms structure straggly up and down between forearm 34 and postbrachium 33, and both are connected as a single entity by axle sleeve 35, and the front portion of forearm 34 is provided with Roller bearing 37, the rear portion of postbrachium 33 is provided with driving wheel supporting roller 36, and driving wheel is docked with wheel 36 with driving wheel；Upper lever 22 and lower lever 16 are fixed between foreboard 7 and back plate 6 each via the activity of a guide shaft 19 and form lever construction.

Reference picture 1, Fig. 7 and Fig. 8, upper cutter slide 23 have a chute, and the roller bearing 37 of the front portion of upper lever 22 is stuck in be cut The structure movable up and down of upper cutter 24 is formed in the chute of knife slide 23；Lower cutter slide 18 also has a chute, lower lever The roller bearing 37 of 16 front portions is stuck in the chute of lower cutter slide 18 and forms lower cutter 21 and can slide up and down structure.Simultaneously as The presence of chute in upper cutter slide 23 and lower cutter slide 18 so that upper cutter 24 and lower cutter 21 can be with upper cutter slides 23 and lower cutter slide 18 reciprocatingly moved in the drive of driving plate 12.

Reference picture 1, Fig. 6 and Fig. 8, the upper driving wheel 10 and lower driving wheel 8 have identical structure, and its sheave surface is equal It is nonplanar structure, but the thickness of wheel disc is uniform, and upper convex portion and lower concave part are respectively provided with thereon, and upper convex portion and lower concave part are mutually handed over Replace, the surface of wheel disc is to seamlessly transit；Upper driving wheel 10 and lower driving wheel 8 are staggered；The driving wheel supporting roller 36 is parallel Two are provided with, the wheel disc of upper driving wheel 10 is stuck between two driving wheel supporting rollers 36 of upper lever 22, and the wheel of lower driving wheel 8 Disk is then stuck between two driving wheel supporting rollers 36 of lower lever 16；By swing turn of upper driving wheel 22 and lower driving wheel 16 It is dynamic to be converted into the rocking action of upper lever 22 and lower lever 16 to drive upper cutter 24 and lower cutter 21 through driving wheel supporting roller 36 Move up and down.As a example by above driving wheel 10 specifically, when the upper convex portion in the wheel disc of upper driving wheel 10 is rotated to driving wheel When between supporting roller 36, the tail end of upper lever 22 is lifted, and front end pushes, and upper cutter 24 is moved downward；Conversely, working as upper driving wheel 10 Wheel disc in lower concave part rotate during between driving wheel supporting roller 36, the tail end of upper lever 22 is pushed, and front end upwarps, upper cutter 24 motions upwards.Lower cutter 21 is identical with the action process principle of lower driving wheel 8, and difference is, upper driving wheel 10 and lower driving Wheel 8 is staggered, therefore, the action process of lower cutter 21 and upper cutter 24 is carried out in reverse direction, i.e., when upper cutter 24 to During lower motion, the then motion upwards of lower cutter 21.

Reference picture 4 and Fig. 5, the Cam Follower 28 include two rollers, are mounted on unloading the head end of power base 27, One of roller promotes cam 9 to connect with contact pin, and another roller connects with catch bar 13.

A fixed block 30 is provided with lower plate 4, the tail end for unloading power base 27 is installed on the fixed block by a fixing axle 29 Swingable structure is constituted on 30.

Reference picture 1, is fixed by a guide pin bushing 38 respectively between upper lever 22 and lower lever 16 and respective guide shaft 19.

Reference picture 1, Fig. 2 and Fig. 6, the front end of main shaft 5 are provided with optoelectronic switch 31, and optoelectronic switch 31 is close to the one of main shaft 5 Side, the anti-dazzling screen 32 matched with optoelectronic switch 31 is then fixed on main shaft 5, and optoelectronic switch 31 is together with anti-dazzling screen 32 by a protection Plate（Do not identify）Cover.The function of optoelectronic switch 31 mainly has at 2 points, and one is to determine（Main shaft 5, contact pin promotes cam 9 and drives Wheel）Relative zero；Two is that motor 1 is eliminated by way of " clear point "（Servomotor）Cumulative errors in the process of running.

Action process explanation：

Reference picture 9, it is initial position to set 0 ° of angle during contact pin promotes cam 9 and two sequential of driving wheel.

1, motor 1 is rotated, and during to 21 ° of angles, lower driving wheel 8 prizes lower cutter 21 and moves up by lower lever 16, incision Knife 21 starts retainer action；

2, during to 41 ° of angles, upper driving wheel 22 prizes upper cutter 24 and starts to move down by upper lever 22, and upper cutter 24 is opened Beginning does blank action；

3, during to 46 ° of angles, lower cutter 21 stops moving up, and lower cutter 21 has held terminal 25；

4, during to 86 ° of angles, upper cutter 24 stops moving down, and contact pin promotes cam 9 to start to promote contact pin mechanism 11 to move, Terminal 25 is had been turned off, starts contact pin（Lower cutter is now gone up to clamp terminal 25）；

5, during to 176 ° of angles, contact pin mechanism 11 stops reach；Terminal is already inserted into plastic casing（housing）；

6, during to 181 ° of angles, upper cutter 24 is moved up, and lower cutter 21 is moved down, and upper lower cutter opens；

7, during to 196 ° of angles, contact pin promotes cam 9 to shift the continuation of contact pin mechanism 11 onto and moves forward, and starts riveting terminal and enters plastic casing；

8, during to 201 ° of angles, upper cutter 24 stops moving up, and lower cutter 21 stops moving down, and terminal 25 continues riveting and enters Plastic casing 26；

9, during to 226 ° of angles, contact pin mechanism 11 stops reach, and terminal 25 continues riveting and enters plastic casing 26；

10, during to 246 ° of angles, lower cutter 21 continues to move down, and terminal 25 continues riveting and enters plastic casing 26, lower cutter 21 after It is continuous to open；

11, during to 261 ° of angles, contact pin mechanism 11 is moved after starting, and contact pin, riveted are completed；

12, during to 266 ° of angles, lower cutter 21 stops moving down, and lower cutter 21 returns to original position；

13, during to 271 ° of angles, upper cutter 24 stops moving up, and upper cutter 24 returns to original position；

14, during to 341 ° of angles, contact pin mechanism 11 moves after stopping, and contact pin mechanism 11 returns to original position；

15, during to 360 ° of angles, contact pin mechanism 11 returns to original state.

So far, the action of a cycle is completed, and is so gone round and begun again.

Each technical characteristic of embodiment described above can be combined arbitrarily, to make description succinct, not to above-mentioned reality Apply all possible combination of each technical characteristic in example to be all described, as long as however, the combination of these technical characteristics is not deposited In contradiction, the scope of this specification record is all considered to be.

Below the utility model is described in detail, the above, only the preferred embodiment of the utility model and , it is when the utility model practical range can not be limited, i.e., all to make impartial change and modification according to the application scope, all should still belong to this In utility model covering scope.

Claims (10)

1. a kind of cam pin module, including contact pin mechanism and contact pin promote cam, it is characterised in that：Also include motor, master Axle, driving wheel and cutter mechanism, main shaft connect motor by shaft coupling, and contact pin promotes cam and driving wheel to be installed on shape on main shaft Fixed into coaxial, driving wheel is connected with leverage, cutter mechanism also connects the leverage, and contact pin promotes cam to pass through one Unload force mechanisms and be connected with a driving plate, contact pin mechanism is connected with the driving plate, and cutter mechanism is docked with contact pin mechanism；The driving Plate is installed on a pair of slide rails, described to unload force mechanisms and unload power base including one group of Cam Follower and one are swingable, cam with Dynamic device is fixed on and unloads on power base, and Cam Follower with contact pin while promote cam to dock, another side is docked with a catch bar, is pushed away Lever is fixed in the driving plate, and driving plate is connected with resetting means.

2. cam pin module according to claim 1, it is characterised in that：The main shaft is fixed on by bearing block In plate, foreboard, back plate, side plate and upper plate are installed in lower plate, contact pin is promoted cam, driving wheel, Lever machine by above-mentioned each plate Structure and unload including force mechanisms enclose and cover, contact pin mechanism and cutter mechanism are exposed to outside side plate；The slide rail is installed in back plate.

3. cam pin module according to claim 2, it is characterised in that：The driving wheel includes upper driving wheel and lower drive Driving wheel, the leverage includes upper lever and lower lever, and cutter mechanism includes upper cutter and lower cutter；Lower driving wheel connects Lower lever is connect, lower lever front end connects a lower cutter slide, and lower cutter slide is connected with lower cutter fixed seat, and lower cutter is installed on In lower cutter fixed seat, terminal is located on lower cutter；Upper driving wheel connects upper lever, and upper lever front end connects a upper cutter and slides Seat, upper cutter is fixed by upper cutter slide；Upper cutter slide and lower cutter slide are connected with contact pin mechanism.

4. cam pin module according to claim 3, it is characterised in that：The lower lever and upper lever have identical Structure, includes forearm and postbrachium, and structure straggly up and down is formed between forearm and postbrachium, and both are connected as a single entity by axle sleeve, Forearm front portion is provided with roller bearing, and postbrachium rear portion is provided with driving wheel supporting roller, and driving wheel is docked with wheel with the driving wheel；Upper lever and Lower lever is fixed on each via a guide shaft activity and lever construction is formed between foreboard and back plate.

5. cam pin module according to claim 4, it is characterised in that：Upper cutter slide has a chute, upper lever Anterior roller bearing forms upper cutter structure movable up and down in being stuck in the chute of upper cutter slide；Lower cutter slide also has one Chute, the anterior roller bearing of lower lever is stuck in the chute of lower cutter slide and forms lower cutter and can slide up and down structure.

6. cam pin module according to claim 4, it is characterised in that：The upper driving wheel and lower driving wheel have phase Same structure, its sheave surface is nonplanar structure, but the thickness of wheel disc is uniform, and upper convex portion and lower concave part are respectively provided with thereon, Upper convex portion and lower concave part are alternateed, and the surface of wheel disc is to seamlessly transit；Upper driving wheel and lower driving wheel are staggered；The drive Driving wheel supporting roller is parallel to be provided with two, and the wheel disc of upper driving wheel is stuck between two driving wheel supporting rollers of upper lever, and lower drive The wheel disc of driving wheel is then stuck between two driving wheel supporting rollers of lower lever；By swing turn of upper driving wheel and lower driving wheel It is dynamic to be converted into the rocking action of upper lever and lower lever through driving wheel supporting roller to drive moving up and down for upper cutter and lower cutter.

7. cam pin module according to claim 1, it is characterised in that：The Cam Follower includes two rollings Wheel, is mounted on unloading the head end of power base, and one of roller connects with contact pin promotion cam, another roller and catch bar phase Connect.

8. cam pin module according to claim 2, it is characterised in that：A fixed block is provided with lower plate, power bottom is unloaded The tail end of seat is installed on by a fixing axle and swingable structure is constituted on the fixed block.

9. cam pin module according to claim 5, it is characterised in that：Upper lever and lower lever and respective guide shaft it Between fixed by a guide pin bushing respectively.

10. cam pin module according to claim 1, it is characterised in that：Optoelectronic switch is installed in the front end of main shaft, Near the side of main shaft, the anti-dazzling screen matched with optoelectronic switch is then fixed on main shaft optoelectronic switch, optoelectronic switch and anti-dazzling screen Covered by a protection board together.