pendulum dairy gates fitting and maintenance …...addition of solid sight panels – making it...

Version 1.4 P a g e | 1

Pendulum® Dairy Gates

Fitting and Maintenance Instructions

Kit for one gate shown

Leask Engineering Ltd | 3442 State Highway 26 | Tatuanui | Morrinsville 3374

+64 7 889 7769 www.leask.co.nz

http://www.leask.co.nz/


Contents

Introduction ............................................................................................................................................ 3

Kit List ...................................................................................................................................................... 4

Overall Dimensions ................................................................................................................................. 5

Safety Requirements ............................................................................................................................... 6

Other Requirements (not supplied) ........................................................................................................ 7

Tools .................................................................................................................................................... 7

Galvanised Medium Purpose Pipe ...................................................................................................... 7

Gate Installation ...................................................................................................................................... 8

Step 1: Unpack the components ......................................................................................................... 8

Step 2: Cut the lead out rail (if applicable) ......................................................................................... 9

Step 3: Determine the gate angle ..................................................................................................... 10

Step 4: Position the Mounting Frame ............................................................................................... 11

Step 5: Brace the Mounting Frame ................................................................................................... 13

Step 6: Complete the Mounting Frame Welding. ............................................................................. 14

Step 7: Position the Weight Arm ...................................................................................................... 15

Step 8: Hang the Gate ....................................................................................................................... 16

Step 9: Check and adjust the gate closed alignment ........................................................................ 17

Step 10: Check and adjust the gate open alignment ........................................................................ 17

Step 11: Fabricate the closed gate support ...................................................................................... 18

Installation of the opening and closing mechanism ............................................................................. 20

Step 12: Mount the Control Rail ....................................................................................................... 20

Step 13: Attach the Gate Control Rod .............................................................................................. 24

Step 14: Fit the Crank Stopper .......................................................................................................... 25

Step 15: Adjust the Gate ................................................................................................................... 26

Step 16: Completion ......................................................................................................................... 28

Monthly Maintenance .......................................................................................................................... 28

Operation .............................................................................................................................................. 29


Introduction

Pendulum® gates were introduced to New Zealand dairy farmers in 1983 by Leask

Engineering. The Pendulum® exit gate, manufactured for herringbone dairy sheds, offers a

unique design and effective control over cow flow during milking. The gates, which pivot on

sealed ball bearings, are robustly constructed and can be opened from anywhere along the

pit. On opening, the gate swings away from the operator to an overhead position on the

breast rail side of the shed, allowing a clear exit for the cows. Milked and un-milked cows are

easily separated, thus providing rapid exit and entry to the dairy shed (follow through flow).

Individual cows can be stopped, even when they are exiting in close formation. Selected cows

can be drafted from the herd to be attended to after milking.

Pendulum® Gates have always been reowned for providing:

Quick, easy and accurate control

Labour savings

Positive open and closed locking

Large exit area

Since the early days of design, our Pendulum® gate has evolved and developed, and recent

design changes have seen further significant improvements with the following advantages

and features:

Addition of a mounting frame for quicker and easier installaton

Stronger gate frame

Gate quick attach mounting

Heavier control rod ends and bolts

Stonger secondary arm with the weight incorporated inside

Flanged bearing housings

Extra head clearance for personnel

Extra head clearance for the front cows

Addition of solid sight panels – making it easier for the cows to see the moving gate

Better support of the gate frame during opening/closing motion

Ability to use either 15NB or 20NB control rails


Kit List

Item No. Part Number Description Side Qty (2 gates) 1 S004 10 00 00 0 1 Mounting Frame RH 1

S004 10 00 01 0 1 Mounting Frame LH 1

2 S004 20 00 00 0 1 Weight Arm RH 1

S004 20 00 01 0 1 Weight Arm LH 1

3 S004 30 00 00 0 1 Gate (with pin retaining plate) RH 1

S004 30 00 01 0 1 Gate (with pin retaining plate) LH 1

4 S004 40 00 00 0 1 Control Rod (2 piece, 1 rod end) Common 2

5 S004 40 00 02 0 1 Adjuster (with rod end) RH on gate

S004 40 00 03 0 1 Adjuster (with rod end) LH on gate

6 S004 40 30 04 0 1 Crank Lever Common 2

7 S004 40 30 06 0 1 End Bracket Common 2

8 S004 40 65 00 0 1 Handle Common 12

9 S004 40 65 06 0 1 Support Bracket Common 2

10 S004 40 65 08 0 1 15NB Control Rail Ring Common 24

Note: 20NB Control Rail Rings available on request

11 S004 40 65 12 0 1 Crank Stopper with rubber Common 2

12 S004 40 65 14 0 1 Crank Stopper Support Common 2

13 S004 40 65 16 0 1 Front Stopper Common 2

14 S004 40 65 18 0 1 Front Stopper Support Common 2

15 SHAFT COLLAR 28.6 Shaft Collar 1 1/8” Common 2

16 S004 10 65 00 0 1 2070 x 10mm Alignment Rod Common (not shown) 1

Fig.1 Kit for 1 gate shown

2

1

3

4

7

6

5

10

8

9

11

12

15

13

14


Overall Dimensions

Fig 2. Overall Dimensions


Safety Requirements These installation instructions provide guidance for the correct installation of the Pendulum®

gates and are intended to be used by qualified and experienced site engineers, who are

competent and fit to do the job safely. These gates are fitted internationally, therefore local

or site specific health and safety legislative requirements are not detailed within. Installers

must adhere to all local health and safety legislation. It is the responsibility of the personnel

on site to ensure the health and safety of everyone on and around their worksite, including

workers, clients and members of the public. Within New Zealand, the Health and Safety at

Work Act 2015 applies. If you have any queries or concerns regarding safe working practices,

please contact your supervisor, site foreman/manager or local safety advisor before

proceeding.

Leask Engineering is not responsible for the results of any action taken on the basis of

information in this document, or for any errors or omissions. The following safety list is not

exhaustive, but is intended as a quick guide.

Ensure:

The worksite remains safe

You are aware of the site hazards and controls implemented

You report accidents or near misses in the required timeframes

Personal protective equipment is worn in the correct manner (head, eyes, ears, hands,

feet), relative to site hazards and/or other hazards

Tools and equipment

o are right for the job

o have been tested and visually examined by a competent person

o guards are secure and in good repair

o safety devices are operating correctly

All operators are trained and competent

Electrical cables are within test date, and are routed to guarantee safe working

practices

The work area is fenced off from the public

The pit is guarded to prevent accidental falling

Suitable steps or a platform are available (600mm should suffice but depends upon

roof height)

Proper manual lifting techniques are used to avoid injury

Appropriate first aid and fire extinguishing equipment is at hand

Safe work procedures associated with welding or grinding hot works (welding flashes,

fumes, sparks, burns, fire) are followed


Other Requirements (not supplied)

Tools

Marker Grinder with cutting disc for steel

Plumb line or 2m straight edge Spirit Level

Arc welder 2.5, 3 & 4.5mm allen keys

Hammer Measuring Tape

13,15,16,17,18, 19 and 24mm spanners 3.2 (or 2.5) welding rods

Wire Brush G clamp or similar

Paint and painting equipment Grease gun with multipurpose grease

Rope or strap 2 pairs of vice grips

Galvanised Medium Purpose Pipe

15NB – sufficient length for 2 control rails running the full length of the pit or

20NB - for pits longer than 26m, to avoid excess control rail flexing, 20NB control rails are

recommended. If required please contact Leask Engineering for 20NB control rail rings.

32NB – for diagonal bracing to roof rafters and fabrication of closed gate supports, lengths

are site specific.

50NB Breech Rail Front Posts – Minimum height 1940mm from finished floor level,

preferably higher and connected to a roof rafter as shown below. Alternatively connect

the two Breech Rail Front Posts together with a 50NB hoop.

Fig 3. Breech Rail Front Posts connected to the rafter


Gate Installation

The Leask Pendulum® gate has been purposely designed for quick and easy installation.

Please follow these instructions carefully, incorrect installation may shorten the lifespan of

the gate, or make the gate more difficult to operate. Make sure all steps of the installation

process have been completed as instructed.

Instruction steps 2 to 16 are for the LH gate, when viewed with back to exit, looking towards the

cow entrance. Repeat all steps for the opposite side.

Step 1: Unpack the components

Set out the components, dividing the complete kit into left and right kits as shown below

Fig 4. Viewed with back to exit, looking towards cow entrance.

All components are symmetrical (can be used on either side) except for the 6 items shown below.

Fig 5. Close up of handed components (viewed with back to exit, looking towards cow entrance).

1a

1b

3a

2a

2b

3b


Step 2: Cut the lead out rail (if applicable)

If the lead out (A) rail is attached to the breech rail front post (B), cut 250mm off the lead out

rail, measured from the face of the breech rail front post, and scallop the lead out rail an

additional 15mm (to socket over a 50NB post). The gate mounting frame (1) will be inserted

into this space.

Fig 6. Mark the lead out rail

Fig 7. Shortened and scalloped lead out rail.

B

A


Step 3: Mark the floor where the tip of the gate is going to be above

Measure forward from the front face of the breech rail front posts (B). The distance forward

is determined by the cup centres (width allowed for each cow)

Cup centres Distance forward

660mm 1025mm

700mm 1055mm

760mm 1110mm

800mm 1140mm

900mm 1210mm

Place a straight edge (C) across the floor and mark a line on the floor (D). This is the preferred

distance forward for the tip (sweep arc) of the gate.

Fig 8. Place a straight edge the correct distance forward from the front post.

C

B

D


Step 4: Position the Mounting

Frame

Positon and hold the gate mounting

frame (1) against the breech rail front

post.

Note: Gate mount is 21kg and is top heavy, it

is recommended that 2 people position this

item to ensure safe working practices.

The gate height is pre-determined by

placing the base of the mounting

frame on the finished platform

concrete. Contact Leask Engineering

for advice if the roof height is less than

2400mm as the mounting frame may

need to be shortened.

The gate position (relative to the

breech rail front post) is pre-

determined by socketing the 50NB

breech rail front post into the semi-

circular cut out.

Use a strong G clamp or similar to

secure the mount in place. See red

arrows for clamping position.

Also support the mounting frame and

clamp with a rope or strap, to prevent

either from falling if the clamp slips.

Simulate the gate maximum width (tip

of gate sweep arc) by using the

alignment rod as shown Fig 11.

Use a pair of vice grips to clamp the

10mm diameter x 2070mm alignment

rod (16), in the centre of the mounting

frame (see red arrows), and through

the hole/flush with the back of the

frame.

Fig 9. View of mount positioned against the breech rail front post.

Fig 10. View of mount positioned with breech rail front post socketed into the semi-

circular cut out.

Fig 11. Clamp the alignment rod to the mounting frame.

1

D

16


Position the mounting frame at the correct

angle, relative to the pit. Use a spirit level and

straight edge (or plumb line) (E) to ensure the

tip of the alignment rod is directly above the

line drawn on the floor in step 3.

If necessary, loosen the mounting frame G

clamp and rotate the mounting frame (1)

around the breech rail front post (B) to

achieve the correct position above the line.

Retighten the G clamp.

Temporarily hang and swing the gate through

its full motion (if the G clamp allows), to

ensure you have sufficient space for the gate

to operate. It may be necessary to adjust the

mounting frame position relative to existing

obstacles e.g. roof beams.

Note: The gate is 24.5kg, it is recommended that 2

people position this item to ensure safe working

practices.

Important: To ensure the gate shaft is going

to be horizontal, place a spirit level across the

tips of the mounting frame quick attach hooks

and adjust to make it level. When you are

sure the mount is correctly positioned and

level in both directions, tack weld the mount

frame where it is clamped to the breech rail

front post to hold securely in place. To be fully

welded later.

D

Fig 12. Rotate the mounting frame until the tip of the alignment rod is

directly above the line on the floor.

Fig 13. Hang the gate and swing it through its full motion, to ensure there

is sufficient clearance to operate the gate.

Fig 14. Ensure quick attach brackets are level

E

D

1

B


Step 5: Brace the Mounting Frame

Prior to adding any other components to the gate, the mounting frame must be supported by

bracing. Check the mount has remained level (as per step 4) in all directions and tack the

supports in place. Some bracing examples are shown, and a combination of methods may be

required to create a solid support arrangement.

Fig 15. A diagonal support to the rafter Fig 16. Bracing across the pit, connecting the front corner of the LH mounting frame to the front corner

of the RH mounting frame (if head height allows).

Fig 17. Bracing in line with breech rail front post, bolted to the wall. Fig 18. Bracing in line with breech rail front post, concreted into the

floor.


Step 6: Complete the Mounting

Frame Welding.

When you are sure that the mount is

correctly aligned and is level in each

direction (as per step 4), and that the gate

has sufficient space to swing, the

mounting frame can be fully welded to

the supports (fitted in step 5) and then to

the breech rail post at the top (see Fig 20

yellow lines)

Ensure the mount upright is plumb

(parallel to the front post) in each

direction. Weld the mount to the breech

rail post at the bottom (see Fig 21 yellow

lines).

If applicable also weld the mounting

frame to the lead out rail (A).

Clean and paint all welds with a zinc

enriched paint.

Fig 20. Top welding.

Fig 21. Bottom Welding.

Fig 22. Lead out rail.

A


Step 7: Position the Weight Arm

Note: The weight arm is 25kg, it is recommended that 2 people position

this item to ensure safe working practices.

The weight arm (2) can be lifted into position and supported

using a temporary pin placed through the bottom holes of the

weight arm top brackets as shown.

Lift the weight arm and temporary pin up through the middle

of the gate mount.

Rotate the weight arm 90 degrees and feed the guide box

section between the guide rollers.

Allow the temporary pin to carry the weight arm as it rests on

the mounting frame. This keeps the weight arm high enough

to be able to be joined to the gate.

Fig 23. Temporary pin placement

Fig 24. Lift the weight arm up through the mounting frame and rotate 90 degrees

Fig 25. Place the weight arm guide between the

rollers

Fig 26. Weight arm in temporary rest position.

2


Step 8: Hang the Gate

Note: The gate is 24.5kg, it is recommended that

2 people position this item to ensure safe

working practices.

Ensure you have the correct gate - the

adjuster bracket should be on the cow

side of the gate.

Remove the M16 joining bolt from the

gate (3). Place the retaining plate onto

the gate hinge pin.

Hang the gate by placing the gate hinge

pin into the quick attach brackets.

Secure both sides of the hinge pin with

M10 x 35 bolts and nyloc nuts.

Slide the weight arm back towards the

pit, lift the gate up until the pivot holes

are horizontal, slide the weight arm

forward and align the holes. Replace the

M16 joinin bolt and nut taking care not

to damage the plastic bushes. Do not

overtighten the hinge bolt and nut.

Remove the temporary locating pin

from the weight arm.

When fully open there should be a

minimum of 50mm clearance between

the weight arm (1) and the floor. If the

mounting frame has been mounted

lower than normal, the bottom of the

weight arm and the short diagonal box

section will need to be shortened, to

avoid impact and also ensure there is

enough ground clearance to prevent

accidental nips.

Fig 27. Remove the M16 bolt and placement of the hinge pin retaining plate.

Fig 28. Hang the gate and secure the hinge pin.

Fig 29. Join the gate to the weight arm and fasten.

Fig 30. Shorten the weight arm if the ground clearance is less than 50mm

1

3


Step 9: Check and adjust the gate closed alignment

When the gate is closed check if the gate hangs

correctly aligned, central in line with the weight arm

(see fig 31 red arrow).

If not, slacken the 6 bearing bolts and adjust the

gate, retighten the 6 bolts when the gate is vertical,

and resting between the guides.

While moving the gate up and down, make sure the

weight arm is guided between the rollers without

fouling. The gate should be easy to move, without

any tight spots.

Step 10: Check and adjust the gate open alignment

When the gate is fully open, the vertical rails in the gate should be plumb. If not, slacken the

6 bearing bolts and adjust the gate, retighten when the gate rails are vertical. The weight arm

should be sitting central in the mounting frame.

It may be necessary to complete steps 9 and 10 several times to get the gates to sit correctly

in both open and closed positions. Another adjustment option is to loosen the bearing grub

screws, and slide the bearings sideways on the shaft, then retighten the grub screws. In all

cases small adjustments are recommended.

Note: If the gate is adjusted vertical when closed (as per step 9), once the gate is fully opened

the weight arm will also have moved sideways as illustrated in per fig 34.

Fig 32. Check the gate is plumb. Fig 33. Adjust open gate Fig 34. Check the weight arm is central in the mounting frame.

Fig 31. Check gate hangs central to the weight arm.


Step 11: Fabricate the closed gate support

It is critical that the corner of the gate is supported when in the fully closed position, otherwise

cows could force and bend the gate from either side. A closed gate support is required to

both prevent the cows pushing the gate sideways and also to catch and open the gate

extension (F) as the gate pivots closed.

The size and shape of the closed gate support is site specific therefore is not part of the

supplied kit. Catches and catch supports are included in the kit (see fig 37, items 13 & 14).

Tie the gate and weight arm

tightly together in the closed

position (see fig 35 red

arrows).

Pivot the gate extension (F)

out fully until there is 10mm

clearance at its rubber stopper

(G). Clamp the extension in

this position. The closed gate

support can be fabricated to

suit the gate in this position as

shown in figs 36 and 37.

Use 32NB galvanised pipe to

construct a support (H) from

the front headrail post (J).

Tack the closed gate support in

position. The gate must be

able to swing over the

horizontal stopper (13) (with

25mm clearance in all

directions), but the tip of the

gate extension (F) must catch

on the stopper forcing it to

almost fully extend as shown

in fig 37.

Untie the gate and weight arm, swing the gate through its opening and closing motion and

check the clearance between the gate and the stopper.

When you are sure the closed gate support is in the correct position, complete the closed gate

support welding. Clean and paint the welds.

Fig 35. Tie the gate and weight arm together. Gate fully closed and almost fully extended.

Fig 36. Example of a closed gate support Fig 37. Gate extension can’t get past the closed

configured to suit feeding troughs. support.

F

F

H

G

J

13&14


Fig 38. Gate fully closed.

Fig 39. Gate fully open.


Installation of the opening and closing mechanism

Step 12: Mount the Control Rail

It is recommended that initially only one length of control rail is fitted. The remainder can

be fitted upon completion of the gate set up.

Typically 15NB galvanised pipe is used for the pit control rails (K) and is

fitted along the full length and each side of the pit, enabling the gates to

be operated from anywhere along the pit. However for pits longer than

26m, to avoid excess control rail torsional flexing, 20NB control rails are

recommended. If so please contact Leask Engineering and request 20NB

control rail rings.

12 rings (item 10) are supplied for mounting the 15NB control rails on

each side. When fitted, the rail should be straight and easy to rotate.

The position of the control rail rings and brackets will depend upon how

close the breech rail front post is to the edge of the pit. If the post is at

or close to the edge of the pit, (within 125mm from pit edge to post face)

skip option 1 and instead go to option 2, or vice versa.

Option 1 - The breech rail front post is spaced away from the edge of the pit (>125mm from

the edge of the pit to the post face).

Weld two or three control rail rings (10) to the back of the

breech rail, placing the first ring close to the gate as shown in

fig 40 above. Slide a control rail through the rings.

Slide the crank lever (6) over the 15NB control rail (L) as

shown (or butt against the 20NB control rail), with the arm

towards the cow entry. Fully weld ensuring the axis is

straight.

Accurately measure the distance from the centre of the crank

lever pipe (6) to the face of the breech rail front post (B). Mark

and cut the Support Bracket (9) to suit the above

measurement, then slide it over the crank lever. Support the

weight of the components and tack the support bracket to the

breech rail front post. The bracket must be central to the post

and perpendicular to the control rail. The control rail must be

easy to rotate.

Fig 40. Gate Control Rail

K

H

Fig 41. Weld the crank lever to the control rail

Fig 42. Measure from centre to face. Shorten and

weld the support bracket central to the front post

6

L

10

H

B

6

9


Slide the shaft collar (15) over the crank lever pipe.

Measure from the centre of the crank lever (6) to the centre

of the gate mounting frame post (1). Cut the end bracket (7)

to suit this measurement.

Grease the end of the crank lever tube. Slide the shortened

end bracket into the crank lever tube. Weld the end bracket

to the mounting frame post (1). The crank must go forward

towards the cow exit. The control rail must be easy to rotate.

Slide the shaft collar (15) up against the support bracket (9)

and lock in position.

Diagonally brace the support plate (9) and the end bracket

(7) (see red arrows)

Fig 43. Slide the locating shaft collar over the crank

lever pipe

Fig 44. Measure from centre to centre

Fig 45. Shorten and weld the end bracket to the

gate mount post. Clamp the shaft collar in place.

Fig 46. Diagonal braces

7

1

1

15

6

15

9

9

7


Option 2 - The breech rail front post is close to the

edge of the pit (<125mm from the edge of the pit

to the post face).

If the breech rail front post is in line with the breech

rail, it will be necessary to space the control rail rings

off the breech rail a minimum of 30mm towards the

centre of the pit, to enable the control linkage to

crank over centre.

The distance from the centre of the breech rail front

post (B) to the centre of the control rail (L) needs to

be a minimum of 65mm.

Accurately measure the above distance, mark and

cut both the support bracket (9) and the end bracket

(7) to suit this measurement.

The distance from the centre of the control rail (L) to

the top face of the mounting frame flat

crossmember (1) must be a minimum of 75mm.

Using the above dimensions, weld two or three

control rail rings (10) to the back of the breech rail,

placing the first ring close to the gate as shown in fig

40 above. Slide a control rail through the rings.

Slide the shaft collar (15) and then the shortened

support bracket (9) onto the crank lever (6). Fit the

crank lever (6) over the 15NB control rail (L) as

shown (or butt against the 20NB control rail), with

the arm towards the cow exit. Fully weld the crank

lever to the control rail, ensuring the axis is straight.

Support the weight of the components and weld the

support bracket (9) to the breech rail front post (B).

The bracket must be on the side of the post and

perpendicular to the control rail. The control rail

must be easy to rotate.

Fig 48. Measure between centres.

Fig 49. Weld the crank lever to the control rail.

15

L

9

6

L

1

B

B


Grease the end of the crank lever

tube. Slide the shortened end bracket

(7) into the crank lever tube (6). Weld

the end bracket (7) to the breech rail

front post (B). The crank must go

forward towards the cow exit. The

control rail must be easy to rotate.

Slide the shaft collar (15) up against

the support bracket (9) and lock in

position.

Fig 51. View of ‘post close to pit edge’ crank lever arrangement.

Fig 50. Weld the shortened end bracket to the breech rail front post.

15

B

7

6

9


Step 13: Attach the Gate Control Rod

Position the adjuster approximately in the middle of the

gate adjustment slot.

Fit the straight section of the control rod (4) to the adjuster

bracket (5).

Fit the dog leg section of the control rod (4) to crank lever

(6). Use the inner hole if the post is close to the pit edge (as

per step 2, option 2), otherwise use the end hole as shown.

Ensure the ball joint is pinched up tight, therefore

preventing the ball rotating on the bolt.

With the gate (3) held hard closed, pivot the crank lever

(6) to the ‘1 o’clock’ position.

Use 2 pairs of vice grips to clamp the 2 pieces of control

rods (4) together, edge to edge.

Do not weld the control rods together yet – further

adjustment will be necessary. This is completed at the

end of step 16.

Fig 53. Attach the straight section of control rod

Fig 54. Attach the ‘dog leg’ section of control rod

4

4

6

4

3

Fig 55. Close the gate and pivot the crank lever to 1 o’clock

Fig 56. Clamp the two sections

of control rod

together

3

4

6

4

4

5


Step 14: Fit the Crank Stopper

Pull a string line (see blue line) from the top control rod ball

joint to the middle of the crank lever pipe.

Push the crank lever (6) forward towards the breech rail

front post until the axis of the bottom ball joint is 30mm

past the string line as shown (this puts the crank over centre

and locks the gate closed).

While the crank lever remains in this position, weld the

crank stopper (11) with rubber bush against the crank lever,

and weld a diagonal brace using the crank lever support bar

(12).

If the breech rail front post is close to the pit (as per Step

12, option 2), a small crank stopper with rubber bush can

be welded to the side breech rail front post as shown.

Fig 57. Pull a string line as shown and position the

crank

Fig 58. Crank stopper (option 1, post offset from pit)

Fig 59. Crank stopper (option 2, post close to the pit)

6

11

12


Step 15: Adjust the Gate

Various adjustments may be necessary, as illustrated.

It is assumed that the control rod overlap (see fig 61) is not welded but instead is clamped

with vice grips for easy adjustment. If an existing gate is being reset, it may be necessary to

clamp the control rod with vice grips (see fig 56) and cut existing welds (see fig 66).

A very small adjustment movement can make a large difference to the gate placement and

swing. Make only one adjustment at a time, open and close the gate and observe the

consequence.

Altering one adjustment can negatively affect another adjustment, a combination of

movements is often required to achieve a proper setting.

When making adjustments – the aim is to get a small rise in resistance as the crank lever goes

over centre in both directions (gate fully open and gate fully closed). If the adjustments are

set too ‘tight’ and there is too much resistance or the crank can’t go over centre, the gate will

be too difficult to operate at the far end of the pit. If the over centre is too slack, the gate

could accidentally open or close. The over centre resistance should be the same for both open

and closed positions.

The gate should move through its full motion without any components fouling (except for

rubber buffers). Adjust as necessary if any components are not positioned properly.

Fig 60. Adjuster/gate slide Fig 61. Control Rod overlap slide

Fig 62. Ball joint roll and length adjustment Fig 63. Adjust the fully open/rubber stopper bolts.


To prevent the gate from bouncing (and causing premature fatigue), it is important that the

gate sits firmly against the rubber stoppers. An incorrectly positioned crank stopper (see step

14) can also cause problems if the crank travels too far, the gate can bounce off its rubber

stoppers.

When fully open, the gate should be compressing the

top stoppers (see red arrows).

When fully closed, the gate should be compressing the

weight arm stopper (see red arrow).

Adjustment Result Other consequence Move adjuster towards the gate hinge pin Increased gate swing (both directions) Control rod may also need reset

Move adjuster away from the gate hinge pin Decreased gate swing (both directions) Control rod may also need reset

Extend Control Rod (at overlap or ball joint) Gate closes further, Opens less

Contract Control Rod (at overlap or ball joint) Gate opens further, Closes less

Ball joint roll – lock nut at ball joint Determine the sideways position of the control rod

Extend spacer bolts under top stop buffers Gate opens less (useful for low roof height) Control rod and adjuster may also

need reset

Shorten spacer bolts under top stop buffers Gate opens less (useful for low roof height) Control rod and adjuster may also

need reset

Problem Action Insufficient roof height Extend spacer bolts under the top stop buffers (see fig 64)

Gate does not open high enough, and does not close fully Move adjuster closer to the gate hinge pin

Gate does not open high enough, but is ok when closed Move adjuster closer to the gate hinge pin and shorten the control rod

Crank lever will not go over centre when gate is fully open Move adjuster away from gate hinge pin and lengthen the control rod

but is ok when gate is closed or shorten the top buffer adjustment bolts.

Gate does not close enough, but is ok when open Move adjuster away from gate hinge pin and lengthen the control rod

Crank lever will not go over centre when gate is fully closed

but is ok when gate is open Move adjuster away from gate hinge pin and lengthen the control rod

Gate open crank over centre is too tight, gate closed is too slack Lengthen control rod

Gate open crank over centre is too slack, gate closed is too tight Shorten control rod

Fig 64. Top stoppers compressed when the gate is

fully open.

Fig 65. Weight arm stoper compressed when the

gate is fully closed.


When you are satisfied that the gates are operating

correctly, weld the two sections of control rod (4)

together and remove the vice grips which were added in

step 13 (or 15 above).

The gate operational weight can be adjusted by

repositioning the weight block on the gate. Slide the

weight towards the hinge pin to make the gate easier to

open. Slide the weight away from the hinge pin to make

the gate easier to close.

Step 16: Completion

Finish installing the remainder of the control rail rings and control rails, welding the rails end

to end. Grease each point where the control rails pass through a control rail ring.

6 handles (item 8) are provided for each side of the pit, to be placed one to the rear of the

first cow, and the remainder equally spaced. More handles are available upon request. The

handles should be carefully placed so that the cows sitting back hard on the breech rail cannot

unlock the gates. Handles should be near vertical when closed (crank lever over centre), and

in a position where fingers can’t be nipped.

Clean and paint all installation welds with a high zinc content paint.

Check all nuts, bolts and grub screws are tight.

Grease each of the bearings and the control rod rings.

Monthly Maintenance

Check all nuts and bolts are tight.

Grease each of the bearings and the control rod rings.

Check the gate adjustment as per step 15, and adjust as necessary.

If rubber buffers are damaged, replace as soon as possible.

Ensure all the moving parts are not fouling during their movement.

All parts are available from Leask Engineering if required.

Fig 66. Weld the control rod.

Fig 67. Adjust the gate weight.

4


Operation

Beware of low head height when walking under the gate.

Keep clear of moving parts, to avoid contact or nips. A gate moving at speed can create a

serious impact.

To make operation easier the gates have been weighted so they are lighter to close (pushing

the handle upwards) than they are to open, (pulling the handle downwards).

When cows are exiting, do not use the front handles to close the gate and stop the cows. The

cows will be watching you and will not see the gate close. Instead operate the gate from

further down the pit.

Do not operate the gate without visually checking it is safe to do so.

Do not operate the gate if any components become loose or damaged. Get the gates repaired

immediately.

The gate should be opened and closed gently to avoid continuous use heavy impacts.

If gates become difficult to operate, adjust the gate as per Step 15, or contact the installer for

advice.

23May17

pendulum dairy gates fitting and maintenance …...addition of solid sight panels – making it...

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