Curved Jaw Type
CJ
CJ-1
Curved Jaw Type
Curved Jaw Couplings From Lovejoy
Introduction
CJ
For over 100 years Lovejoy Inc. has set the standard for straight jaw couplings in the United States and around the world. Now, Lovejoy Inc. is proud to
present the CJ and GS Series, a full line of curved jaw products for the world market. The CJ Series curved jaw coupling provides highly reliable service for
light, medium, and heavy duty electrical motor and internal gas combustion engine applications. The GS Series provides a coupling solution for the motion
control industry This product offering will continue Lovejoy's long history of being the world's premier coupling supplier.
The Curved Jaw Design
The three-piece design incorporates a radial curvature to the jaw face and both radial and axial curvature (crowning) to the elastomer (spider). The curved jaw
hubs are offered in sintered iron, steel, aluminum, cast and nodular iron materials. The CJ Series curved jaw coupling and the variety of urethane elements
allows for angular, parallel, and axial misalignment. The simplicity of the three-piece design makes it easy to assemble. Unlike some metallic coupling designs,
the CJ Series design requires no lubrication. When assembled, the CJ Series offers no metal to metal contact of parts. The elastomer in compression design
offers the benefit of continuing to function even after the elastomeric element fails (fail-safe design). The torque range of the CJ Series product is 67 to 247.800
in-lbs. Lovejoy offers the CJ Series in a range of product with finished stock metric bores and keyways for sizes 14 through 75/90. Sizes 100-180 are also available with metric bores on a made-to-order basis.
Elastomers (spider materials)
Lovejoy offers four types of spiders for the CJ Series curved jaw coupling product line.
Urethane spiders provide high abrasion resistance and elasticity, along with good damping
characteristics. The spiders are offered in a variety of shore hardnesses, each providing a
different level of torque capacity, damping, and chemical resistance. The 92 shore spider (white
or yellow) is standard, offering excellent torque carrying capacity. The 80 shore spider (blue)
offers the best damping characteristics. The 95/98 shore spider (red) offers the highest torque
carrying capacity. The 64 shore spider (green) is offered for high humidity environments. The
standard spiders also feature an open center to accommodate small between shaft end measurements. All standard spiders have a rated temperature capacity of 212 °C. (See page 12 for
GS spider temperature ratings.) The urethane material also resists oil, dirt, sand, grease, moisture, many solvents, as well as the atmospheric effects of ozone.
Standard Spider Design
Elastomer Recommendation Chart
Spider Type
80 shore A (Blue)
92 shore A (Yellow)
95/98 shore A (Red)
64 shore (green)
Application types requiring:
Good damping properties
General & hydraulic applications
High torque requirements
High humidity environments
Elastomer Performance Data
Spider Type
80 Shore A
92 Shore A
95/98 Shore A
Color
Blue
Yellow
Red
Material
Polyurethane
Polyurethane
Polyurethane
Temperature Range
Normal
Maximum
-40 to 212 F
-40 to 248 F
-40 to 212 F
-50 to 248 F
-40 to 212 F
-40 to 248 F
Stock Sizes
14 -180
14 -180
14 -180
Misalignment (inches)
Angular
Parallel
Axial
.9 - 1.3 deg
.008 - 027
.039 - 252
.9 - 1.3 deg
.008 - .027
.039 - 252
.9 - 1.3 deg
.008 - 027
.039 - 252
Typical Applications
Good damping properties
General & hydraulic applications
High torque requirements
Temperature Range
Normal
Maximum
-30 to 230 F
-30 to 266 F
Stock Sizes
14 -180
Misalignment (inches)
Angular
Parallel
Axial
.9 - 1.3 deg
.008 - 027
.039 - 252
Typical Applications
Highly humidity environments
Special Elastomer Data
Spider Type
64 Shore D
CJ-2
Color
Green
Material
Polyurethane
Curved Jaw Type
The CJ Series Selection Process*
Step 1:
Determine the nominal torque of your application:
Next find the columns listing Tkn and Tkmax values listed in Nm
and compare them against the DTkmax figure for your
application. Make sure that the spider/coupling size values are
larger than the application values.
Step 6:
Once the size is selected using the torque values, check the table
on page CJ-6 to make sure the bore size needed will fit in the
coupling.
Step 7:
Double check the overall dimensions of the coupling to
ensure that it will fit in the space allowed for the coupling in
the application.
in-lbs = Tkn = HPx63025
rpm
Step 2:
Calculate your Application Service Factor using the charts below.
The total Service Factor (K) will be:
K = K1 x K2 x K3
Step 3:
Calculate the design torque (DTkmax) of your application.
Design Torque (DTkmax) =
Nominal Torque x service factor.
Step 4:
Using the Elastomer performance data charts on pages CJ-4 &
CJ-5 select the urethane shore hardness which best corresponds
to your relative damping needs in the application.
Application Service Factor (K1)
Application Service Factor
Uniform operation with small masses to be accelerated.
Hydraulic and centrifugal pumps, light generators, blowers,
fans, ventilators, belt/screw conveyors.
Uniform operation with medium masses to be accelerated.
Sheet metal bending machines, wood working machines,
mills, textile machines, mixers.
Irregular operation, with medium masses to be accelerated.
Rotating ovens, printing presses, generators, shredders,
winders, spinning machines, pumps for viscous fluids.
Irregular operation and shocks, with medium masses to be
accelerated Concrete mixers, drop hammers, cable cars,
paper mills, compression pumps, propeller pumps, rope
winders, centrifuges.
Irregular operation and very heavy shocks, with large
masses to be accelerated. Excavators, hammer mills,
piston pumps, presses, rotary boring machines, shears,
forge presses, stone crushers.
Irregular operation and very heavy shocks, with very large
masses to be accelerated. Piston type compressors and
pumps without speed variations, heavy roll sets, welding
machines, brick presses, stone crushers.
*This selection process is based on application factors only. A selection process
is also available using DIN 740 part 2 standard. Consult with Lovejoy Engineering
for details.
Application Service Factor for Starts per Hour (K2)
Service
Factor (K1)
1.0
1,2
Starts per hour
Service Factor (K2)
100
1,0
200
1,2
400
1,4
800
1,6
Application Service Factor for Ambient
Temperature (K3)
Ambient Temperature
Service Factor (K3)
-30 to +30 C
1,0
+40 C
1,2
+60 C
1,4
+80 C
1,6
1,3
Definition of Terms
1,4
1,6
1,8
Tkn
Tkmax
P[kW]
rpm[1/min]
Nm
DTkmax
Tkw
Pkw
BX Hub
Rated coupling torque
Maximum torque of the coupling
Power in kilowatts
Revolutions per minute
Newton meters
Maximum torque of the application
Varying load of an application in kilowatts
Allowable power loss
Extended length hub
CJ-3
CJ
Step 5:
Curved Jaw Type
CJ
Elastomer Torque Ratings
Wind-Up Angle @
Nominal
Maximum
Torque
Torque
Size
Maximum
Speed
14
19/24
24/32
28/38
38/45
42/55
48/60
55/70
65/75
75/90
90/100
100/110
110/125
125/145
140
160
180
19000
14000
10600
8500
7100
6000
5600
4750
4250
3550
2800
2500
2240
2000
1800
1500
1400
6,4°
10°
3,2°
5°
14
19/24
24/32
28/38
38/45
42/55
48/60
55/70
65/75
75/90
90/100
100/110
110/125
125/145
140
160
180
19000
14000
10600
8500
7100
6000
5600
4750
4250
3550
2800
2500
2240
2000
1800
1500
1400
6,4°
10°
3,2°
5°
14
19/24
24/32
28/38
38/45
42/55
48/60
55/70
65/75
75/90
90/100
100/110
110/125
125/145
19000
14000
10600
8500
7100
6000
5600
4750
4250
3550
2800
2500
2240
2000
6,4°
10°
3,2°
5°
Torque [in-lbs]
Torque [Nm]
nominal
maximum
nominal
Urethane Spider - 92 Shore A (Yellow)
66
133
7
88
177
10
310
620
35
840
1,680
95
1,680
3,360
190
2,345
4,690
265
2,740
5,480
310
3,625
7,250
410
5,530
11,060
625
11,320
22,650
1,279
21,240
42,480
2,400
29,200
58,400
3,299
42,480
84,960
4,799
58,850
117,700
6,649
75,670
151,340
8,549
113,280
226,560
12,798
165,050
330,100
18,647
Urethane Spider - 98 Shore A (Red)
111
221
13
150
300
17
530
1,000
60
1,415
2,830
160
2,875
5,750
325
3,980
7,960
450
4,645
9,290
525
6,060
12,120
685
8,320
16,640
940
16,990
33,980
1,920
31,860
63,720
3,600
43,805
87,610
4,949
63,720
127,440
7,199
88,500
177,000
9,999
113,280
226,560
12,798
169,920
339,840
19,198
247,800
495,600
27,996
Urethane Spider - 80 Shore A Sizes 14 - 125 (Blue)
35
71
4
43
86
5
151
301
17
407
814
46
823
1637
93
1151
2301
130
1328
2655
150
1593
3186
180
1814
3628
205
4204
8408
475
10399
20798
1,175
14249
28497
1,610
17258
34515
1,950
21594
43188
2,440
Rated HP @
maximum
1200
1800
15
20
70
190
380
530
619
819
1,250
2,559
4,799
6,598
9,599
13,298
17,098
25,597
37,295
1.2
1.7
5.9
16
32
45
52
69
105
215
400
550
800
1120
1440
2150
3140
1.9
2.5
8.9
24
45
65
75
100
150
320
600
825
1210
1680
2160
3230
4715
25
34
113
320
650
899
1,050
1,369
1,880
3,839
7,199
9,898
14,398
19,997
25,597
38,395
55,993
2.1
2.5
10
25
55
75
85
115
150
320
600
800
1210
1685
2150
3235
4720
3.2
4
15
40
80
110
125
170
225
480
900
1250
1820
2525
3235
4850
7080
8
10
34
92
185
260
300
360
410
950
2,350
3,220
3,900
4,879
1
1
3
8
16
22
25
30
35
80
198
271
329
411
2
3
9
23
47
66
76
91
104
240
594
814
986
1234
*Lovejoy recommends using 30 m/s as maximum speed. For operating speed above maximum use only steel or nodular iron hubs, dynamic balancing required.
CJ-4
Curved Jaw Type
Elastomer Torque Ratings (Continued)
14
19/24
24/32
28/38
38/45
42/55
48/60
55/70
65/75
75/90
90/100
100/110
110/125
125/145
140
160
180
19000
14000
10600
8500
7100
6000
5600
4750
4250
3550
2800
2500
2240
2000
1800
1500
1400
Wind-Up Angle @
Nominal
Maximum
Torque
Torque
4,5°
7,0°
2,5°
3,6°
Torque [in-lbs]
nominal
maximum
Urethane Spider 64 Shore D (Green)
142
283
185
370
660
1,320
1,770
3,540
3,585
7,170
4,955
9,910
5,795
11,590
7,300
14,600
10,395
20,790
21,240
42,480
39,825
79,650
54,735
109,470
79,650
159,300
110,630
221,260
141,600
283,200
212,400
424,800
309,750
619,500
Torque [Nm]
Rated HP @
nominal
maximum
1200
1800
16
21
75
200
405
560
655
825
1,174
2,400
4,499
6,184
8,999
12,499
15,998
23,997
34,996
32
42
149
400
810
1,120
1,309
1,650
2,349
4,799
8,999
12,368
17,998
24,998
31,996
47,994
69,991
2.7
3.5
12.5
30
65
90
110
125
190
400
750
1040
1515
2100
2690
4045
5900
4.1
5
18
50
100
140
165
200
290
600
1125
1550
2275
3160
4045
6060
8850
*Lovejoy recommends using 30 m/s as maximum speed. For operating speed above maximum use only steel or nodular iron hubs, dynamic balancing required.
CJ-5
CJ
Size
Maximum
Speed
Curved Jaw Type
CJ
Coupling Dimensions And Materials
Curved Jaw Coupling
Configuration One—2 A Hubs
Size
14
19/24
24/32
28/38
38/45
42/55
48/60
55/70
65/75
75/90
90/100
100
110
125
140
160
180
Hub Style
B Style
BX Style
A Style
B Style
BX Style
A Style
B Style
BX Style
A Style
B Style
BX Style
A Style
B Style
BX Style
A Style
B Style
BX Style
A Style
B Style
BX Style
A Style
B Style
BX Style
A Style
B Style
BX Style
A Style
B Style
BX Style
A Style
B Style
BX Style
B Style
B Style
B Style
B Style
B Style
B Style
Min.
Bore
S
S
S
S
S
S
S
S
S
0.374
S
S
0.472
S
S
0.984
S
S
1.57
Cast AL
Max.
Bore
0.625
0.625
0.748
0.938
0.938
0.945
1.250
1.250
1.100
1.500
1.500
1.500
1.750
1.750
1.650
2.125
2.125
1.875
2.312
Cast Iron
Min. Max.
Bore Bore* HD
HD
—
—
1.26
—
—
1.57
—
—
1.89
—
—
2.60
—
—
2.95
S
1.650
— 1.250 2.125
—
3.35
S
1.875
— 1.570 2.312
2.95
—3.35
—
S
2.125
1.850 2.750
3.86
—
S
2.500
2.250 2.938
4.53
—
S
2.938
2.000 3.500
5.31
—
S
3.500
3.000 3.938
6.30
—
*Maximum bore may be achieved through the use of a shallow keyway
CL = Distance between spider and hub face.
Max Bore refers to maximum straight bore with keyway allowed in hub.
S= Solid hub with no bore.
CJ-6
Configuration Two—2 B Hubs
Hub Dimensions (inches)
Nodular Iron
PM/Steel
Min. Max.
Min.
Max.
LTB1
Bore Bore* HD Bore Bore* HD & LTB2
0.625
—
0.43
S
0.625
—
0.73
S
0.748 1.26 0.98
0.236 0.938
—
0.98
S
0.938
—
1.46
S
0.945 1.57 1.18
0.315 1.250
—
1.18
S
1.250
—
1.97
S
1.100 1.89 1.38
0.394 1.500
—
1.38
S
1.500 —2.36
S
1.500 2.60 1.77
0.551 1.750
—
1.77
S
1.750
—
2.76
S
1.650 2.95 1.97
S
2.125
—
1.97
S
2.125
—
2.95
S
1.875 3.35 2.20
S
2.312 —2.20
S
2.312
—
3.15
S
2.125 3.86 2.56
S
2.750
—
2.56
S
2.750
—
3.54
S
2.500 4.53 2.95
S
2.938
—
2.95
S
2.938
—
3.94
S
2.938 5.31 3.35
S
3.500
—
3.35
S
3.500
—
4.33
S
3.500 6.30 3.94
S
3.938
—
3.94
S
3.938
—
4.92
1.57 4.250 7.87
4.33
2.36 4.875 9.06
4.72
2.36 5.625 10.43
5.51
2.00
6.250 10.04 6.10
2.00
7.250 11.42 6.89
2.00
7.625 12.80 7.68
G
0.51
0.51
0.63
0.63
0.63
0.70
0.70
0.70
0.79
0.79
0.79
0.94
0.94
0.94
1.02
1.02
1.02
1.10
1.10
1.10
1.18
1.18
1.18
1.38
1.38
1.38
1.57
1.57
1.57
1.77
1.77
1.77
1.97
2.17
2.36
2.56
2.95
3.35
CL
0.06
0.06
0.08
0.08
0.08
0.08
0.08
0.08
0.10
0.10
0.10
0.12
0.12
0.12
0.12
0.12
0.12
0.14
0.14
0.14
0.16
0.16
0.16
0.18
0.18
0.18
0.20
0.20
0.20
0.22
0.22
0.22
0.24
0.26
0.28
0.30
0.35
0.41
OD is equal to HD for B style aluminum sizes: 19, 24, and 28.
W = Spider Thickness.
Outside diameter of spider equal to OD.
H = Inside diameter of spider.
W
0.39
0.39
0.47
0.47
0.47
0.55
0.55
0.55
0.59
0.59
0.59
0.71
0.71
0.71
0.79
0.79
0.79
0.83
0.83
0.83
0.87
0.87
0.87
1.02
1.02
1.02
1.18
1.18
1.18
1.34
1.34
1.34
1.50
1.65
1.81
2.56
2.95
3.35
OAL
1.38
1.97
2.60
2.60
3.54
3.07
3.07
4.65
3.54
3.54
5.51
4.49
4.49
6.46
4.96
4.96
6.93
5.51
5.51
7.40
6.30
6.30
8.27
7.28
7.28
9.25
8.27
8.27
10.24
9.65
9.65
11.61
10.63
11.61
13.39
14.76
16.73
18.70
T;U OD
1.18
1.18
0.79 1.57
1.57
1.57
0.94 2.17
2.17
2.17
1.10 2.56
2.56
2.56
1.46 3.15
3.15
3.15
1.57 3.74
3.74
3.74
1.77 4.13
4.13
4.13
2.05 4.72
4.72
4.72
1.85 5.31
5.31
5.31
2.09 6.30
6.30
6.30
2.44 7.87
7.87
7.87
8.86
10.04
11.42
12.60
14.57
16.54
H
0.39
0.39
0.71
0.71
0.71
1.06
1.06
1.06
1.18
1.18
1.18
1.50
1.50
1.50
1.81
1.81
1.81
2.01
2.01
2.01
2.36
2.36
2.36
2.68
2.68
2.68
3.15
3.15
3.15
3.94
3.94
3.94
4.45
5.00
5.79
6.50
7.48
8.66
Curved Jaw Type
Hub Designs (Descriptions)
Keyway With Set Screw (KW)
Standard Lovejoy method of securing a
hub to a shaft. Clamping style
recommended for backlash free torque
transmission.
Without Keyway,
With Set Screw
Set screw used to secure hub to
shaft.
CJ
Spline Hub With Set
Screw (W/SS)
Spline Hub With Clamp
(SC)
Hub bored to accept standard S.A.E.
and metric spline, secured with set
screw to shaft.
Hub bored to accept standard S.A.E.
and metric spline, secured utilizing a
clamping feature.
Spline Hub With L-Loc
(L-LOC)
Clamping Hub With Single
Slot Without Keyway (C)
Hub bored to accept standard SAE
and metric spline using the more efficient L-Loc feature to secure
hub on shaft.
Zero backlash clamping style for
torque transmission. Torque capacity
of hub depends on bore sizes.
Clamping Hub With Single
Slot With Keyway (CWK)
Hub With Frictional
Locking Device (LD)
Zero backlash clamping style with
keyway for torque transmission.
This hub utilizes a shaft locking device
to allow for shaft engagement.
CJ-7
Curved Jaw Type
CJ Series Powdered Metal (PM) and Cast Iron (CI) Hubs Metric Bore Sizes
CJ
When referencing a Lovejoy Item (UPC) number, include 685144 as a prefix to the number shown in the table
Metric Bore
Size
RSB*
8mm
9mm
10mm
11mm
12mm
14mm
15mm
16mm
18mm
19mm
20mm
22mm
24mm
25mm
26mm
28mm
30mm
32mm
34mm
35mm
38mm
40mm
42mm
45mm
48mm
50mm
55mm
60mm
63mm
65mm
70mm
75mm
79mm RSB
80mm
85mm
90mm
100mm
Keyway
14
Size B Hub
61150
2x1
3 x 1.4
3 x 1.4
4 x 1.8
4 x 1.8 61151
5 x 2.3 61152
5 x 2.3
5 x 2.3
6 x 2.8
6 x 2.8
6 x 2.8
6 x 2.8
8 x 3.3
8 x 3.3
8 x 3.3
8 x 3.3
8 x 3.3
10 x 3.3
10 x 3.3
10 x 3.3
10 x 3.3
12 x 3.3
12 x 3.3
14 x 3.8
14 x 3.8
14 x 3.8
16 x 4.3
18 x 4.4
18 x 4.4
18 x 4.4
20 x 4.9
20 x 4.9
n/kw
22 x 5.4
22 x 5.4
25 x 5.4
28 x 6.4
Powdered Metal
19/24
24/32
B Hub B Hub
61154 60880
72152
71146
65609
61155
69096
67395
70481
61156
65080
61157
61101
71970
69336
64810
61102
61103
67509
61104
61105
61106
68739
28/38
B Hub
60881
70186
69376
71983
68549
71984
61109
61164
66855
61110
61165
61111
61112
65320
67223
61113
*RSB maybe supplied as a solid hub or rough stock bore.
CJ-8
38/45
B Hub
60882
42/55
A Hub B Hub
62414 62048
48/60
A Hub B Hub
62415 62059
Cast Iron
55/70
A Hub B Hub
62416 62060
65/75
A Hub B Hub
62417 62061
75/90
A Hub B Hub
62418 62062
69805
71147
68918
72149
71143
72150
65804
66442
60900
68741
60901
60902
60903
60904
60905
69493
60906
66765
66257
62049
62050
62051
67238
62052
62053
66824
69800
72031
66897
70922
62054
62055
62056
62057
62058
72032
68037
69280
72033
69326
72034
72035
72036
72040
71385
70056
72041
71933
66826
71299
72043
72044
69787
67513
69219
72038
72039
72047
66195
72047
72048
72049
72049
69563
70240
69293
70376
68074
70344
69481
71739
68170
72050
67335
70231
72053
72054
72055
68614
72056
72057
72058
62063
72059
72060
72061
69066
Curved Jaw Type
CJ Series Aluminum and Steel BX Style Hubs
CJ Series Aluminum Hubs Metric Bore Sizes
When referencing a Lovejoy Item (UPC) number, include 685144 as a prefix to the number shown in the table
Keyway
Size
n/kw
2x1
2x1
3 x 1.4
3 x 1.4
4 x 1.8
4 x 1.8
5 x 2.3
5 x 2.3
5 x 2.3
6 x 2.8
6 x 2.8
6 x 2.8
8 x 3.3
8 x 3.3
8 x 3.3
8 x 3.3
10 x 3.3
10 x 3.3
10 x 3.3
12 x 3.3
12 x 3.3
14 x 3.8
14 x 3.8
14 x 3.8
16 x 4.3
18 x 4.4
18 x 4.4
20 x 4.9
14
B Hub
71577
71942
71943
71944
71945
71946
71947
71948
71949
A Hub
71441
19/24
B Hub
71442
24/32
A Hub
71443
28/38
B Hub
71444
A Hub
71445
38/45
B Hub
71446
A Hub
71447
42/55
B Hub
71448
A Hub
71449
71994
71995
72009
72010
72011
72012
72013
B Hub
71450
48/60
A Hub B Hub
71451 71452
CJ
Metric Bore
Size
RSB*
6mm
8mm
9mm
10mm
11mm
12mm
14mm
15mm
16mm
18mm
19mm
20mm
24mm
25mm
28mm
30mm
32mm
35mm
38mm
40mm
42mm
45mm
48mm
50mm
55mm
60mm
65mm
70mm
71951
71952
71953
71954
71950
71956
71957
71958
71961
71962
71963
71964
71965
71966
71967
71959
71971
71968
71969
71972
71973
71974
71975
71976
71977
71978
71979
71980
71981
71982
71986
71987
71988
71989
71990
71991
71992
71993
72014
72015
72016
72017
72019
72020
72021
72022
72023
72024
72025
72026
72027
72028
72029
72030
*RSB maybe supplied as a solid hub or rough stock bore.
CJ Series Steel BX Style Hub Metric Bore Sizes
When referencing a Lovejoy Item (UPC) number, include 685144 as a prefix to the number shown in the table
Metric Bore
Size
Solid
14mm
19mm
24mm
28mm
30mm
40mm
45mm
48mm
55mm
65mm
70mm
Keyway
Size
n/kw
5 x 2.3
6 x 2.8
8 x 3.3
8 x 3.3
8 x 3.3
12 x 3.3
14 x 3.8
14 x 3.8
16 x 4.3
18 x 4.4
20 x 4.9
14
72062
72063
19/24
72066
72064
72065
24/32
72067
28/38
72070
38/45
72073
42/55
72076
48/60
72080
72078
72079
72077
72081
55/70
72082
72068
72069
72071
72072
72074
72075
CJ-9
CJ
Curved Jaw Type
Coupling Installation and Misalignment Capabilities
Coupling Size
Dimensions
G
CL
H
S
14
0.51
0.06
0.39
—
19
0.63
0.08
0.71
1.02
24
0.7
0.08
1.06
1.18
28
0.79
0.10
1.18
1.34
38
0.94
0.12
1.5
1.57
42
1.02
0.12
1.81
1.81
48
1.1
0.14
2.01
1.97
55
1.18
0.16
2.36
2.20
65
1.38
0.18
2.68
2.48
75
1.57
0.2
3.15
2.83
90
1.77
0.22
3.94
3.27
100
1.97
0.24
4.45
3.62
110
2.17
0.26
5.00
4.06
125
2.36
0.28
5.79
4.57
140
2.56
0.3
6.50
5.00
160
2.95
0.35
7.48
5.71
180
3.35
0.41
8.66
6.42
DIST MAX
Kr
OAL
Kw
Ka
DIST MIN
DIST MAX - DIST MIN
Axial Displacement
Radial Displacement
Angular Displacement
Displacement For Displacement/Misalignment (inches)
Max. Axail Displ. (Ka)
Max. Radial Displ. (Kr)
Kw Max angular displ
n=1500 [1/min] in deg (Kw)
Angular Displacement
Set Screw Information
Set Screw Size (SS)
Set Screw Location (t)
14
19
24
28
38
42
48
55
65
75
90
100
110
125
140
160
180
0.040 0.047 0.055 0.060 0.070 0.079 0.082 0.087 0.102 0.120 0.133 0.150 0.165 0.180 0.190 0.220 0.250
0.007 0.008 0.009 0.010 0.011 0.012 0.014 0.014 0.016 0.018 0.019 0.020 0.021 0.024 0.024 0.025 0.027
1,2
0.03
1,2
0.03
0,9
0.04
0.9
0.05
1,0
0.07
1,0
0.07
1,1
0.08
1,1
0.09
1,2
0.11
1,2
0.13
1,2
0.17
1,2
0.19
1,3
0.22
1,3
0.25
8-32
0.2
10-24 10-24 5/16-18 5/16-18 5/16-18 5/16-18 3/8-16 3/8-16 3/8-16 3/8-16 1/2-13 5/8-11 5/8-11
0.39 0.39 0.59 0.59 0.79 0.79 0.79 0.79 0.98 1.18 1.18 1.38 1.57
1,2
0.26
1,2
0.3
1,2
0.35
1.77
1.97
1.97
The values regarding displacement are provided assuming normal operating conditions (i.e. temperature, torque with nominal rating of the coupling, speed/RPM rating of
the coupling, and misalignment). Careful installation (i.e. alignment) and periodic inspection should be provided to provide the optimum life of the coupling. Special consideration should be given as to the position of the shafts and the amount of axial movement the coupling will be exposed to. The more accurate the alignment of the
coupling, will result in greater life of the elastomer. A coupling guard and rotating equipment safety procedures should always be followed. Please consult the Lovejoy
web site at www.lovejoy-inc.com for assembly instructions of the curved jaw coupling.
CJ-10
Curved Jaw Type
Spacer Type and Center Drop Out Designs
• Hubs available in aluminum, sintered iron, cast iron, and steel.
• Spacer style features an aluminum spacer piece.
• Drop-out style features two inserts for increased damping and parallel misalignment
capability.
• Center drop-out design provides easy element replacement.
• Designed to accommodate a larger shaft separation.
CJ
Extended Spacer Styles
• Extended Spacer Style for extension between shaft end measurements.
• Increased parallel misalignment capacity.
• Easy replacement.
Standard Drop-out Styles
• Standard Drop-out design features easily removable components.
• Available in cast and nodular iron sizes 24-180.
Shaft-to-Flange
Flange-to-Flange Styles
• Flange-to-Flange design available for applications requiring space saving, compact
connections.
• Shaft-to-Flange design is also available for special application situations requiring an
alternative connection.
CJ-11
Curved Jaw Type
CJ
Technical Description For The GS Series
The GS Series curved jaw coupling offers zero backlash capability in a 3-piece design. The coupling is provided assembled under prestress. The GS Series
can be used in a variety of different applications requiring precision and accuracy.
The GS Series spider features a straight center of the spider tooth, providing higher stiffness due to coupling prestress. The crowning of the ends of the spider
legs allows for misalignment, while the curved jaws and solid spider center provide high-speed capability.
The jaws of the hubs and the spider legs are chamfered to provide easy assembly. The GS Series coupling design also allows the blind assembly in tight
spaces. Raised spider dots on the legs of the spider ensure proper spacing of hubs and spider.
Proper installation of the coupling can provide isolation of electrical currents. Check the CL dimension listed on page 19 to ensure the proper spacing between
spiders and hubs.
The GS Series coupling has spiders available in four different shore hardnesses. Each spider offers benefits for different vibratory, environmental, and torque
transmission requirements.
Elastomer Performance Data
Spider Type
80 Shore A GS
92 Shore A GS
Color
Blue
Yellow
Material
Urethane
Urethane
Temperature Range
Normal
Maximum
-50 to 176 F
-80 to 248 F
-40 to 194 F
-50 to 248 F
95/98 Shore A GS
Red
Urethane
-30 to 194 F
-40 to 248 F
14 -75
64 Shore D GS
Green
Urethane
-20 to 230 F
-30 to 248 F
14 -55
CJ-12
Sizes Available
14 -24
14 -55
Typical Applications
Electric measuring systems
Electric measuring systems
and control systems
Positioning drives, main spindle
drives, high load applications
High load applications
torsiionally stiff spider material
Curved Jaw Type
Coupling Selection For The GS Series
Typical Applications
Measurement And Control Systems
The torsional stiffness of the GS Series coupling provides zero backlash needed for the accuracy for measurement and control systems. The low torques of
these applications gives the GS Series the ability to provide zero backlash due to the elastomer pre-stress.
The GS Series provides a zero backlash, flexible connection for servo and positioning drives. An added benefit of the GS Series is its damping capabilities. For
applications that have vibrations at critical speeds, the GS Series coupling can provide a zero backlash solution for vibration problems.
Main Spindle Drives
The GS Series coupling is used in main spindle drives for machine tools. Torque spikes and cyclical loading are handled by the GS Series by damping or by
shifting the vibratory frequency range to a non-critical speed range.
GS Series Service Factors
Temperature Factor
K3
-30 to +30C
1
+40 C
1,2
Torsional Stiffness Factor
+60 C
1,4
+80 C
1,8
K4
Main
Spindle
Drive Of
Machine
2-5
Positioning
Drive
3-8
Shock Load Factors
Shaft
Encoders,
Angle
Encoders
10
Light Shock Loads
Medium Shock Loads
Heavy Shock Loads
K5
1,0
1,4
1,8
Calculation Formula
Rated nominal torque Tkn [in-lbs] = HP x 63025
RPM
Rotational inertia coefficient (driver) =
Moment of inertia (driver)
Moment of inertia (driver) + Moment of inertia (driven)
Rotational inertia coefficient (driven) =
Moment of inertia (driven)
Moment of inertia (driver) + Moment of inertia (driven)
Check the nominal torque for the application against the rating for the coupling:
Tkn > Rated torque of machine x K3 x K4
Peak Torque
Shock load (driver side) = Peak torque (driver) x rotational inertia coefficient (driver) x K5
Shock load (driven side) = Peak torque (driven) x rotational inertia coefficient (driven) x K5
Check the peak torque for the application against the rating for the coupling (see page 15), checking both driver and driven sides:
Tkmax > Peak Torque (driver or driven side) x K3 x K4
CJ-13
CJ
Servo And Positioning Drives
Curved Jaw Type
GS Series Technical Description
Maximum Speed for Clamping Styles
(RPM)
CJ
Coupling
Size
14
19/24
24/32
28/38
38/45
42/55
48/60
55/70
65/75
75/90
CJ-14
Spider
Clamping
Durometer
Hub
80 Sh A
92 Sh A
12700
98 Sh A
64 Sh D
80 Sh A
92 Sh A
9550
98 Sh A
64 Sh D
92 Sh A
98 Sh A
6950
64 Sh D
92 Sh A
98 Sh A
5850
64 Sh D
92 Sh A
98 Sh A
4750
64 Sh D
92 Sh A
98 Sh A
4000
64 Sh D
92 Sh A
98 Sh A
3600
64 Sh D
92 Sh A
98 Sh A
3150
64 Sh D
95 Sh A
2800
95 Sh A
2350
Set Screw
Hub
15900
11900
8850
7350
5950
5000
4550
3950
3500
2950
Torque (in-lbs)
Locking Device Hub Tkn
35.4
66.4
25400
31800
110.6
141.6
43.4
88.5
19000
23800
150.5
185.9
309.8
13800
17300
531
663.8
840.8
11700
14700
1416
1770
1681
9550
11900
2876
3584
2345
8050
10000
3982
4956
2743
7200
9100
4646
5796
3628
6350
7950
6062
7301
5650
7050
8319
4750
5950
12965
Tkmax
70.8
132.8
221.3
283.2
86.7
177
300.9
371.7
619.5
1062
1327
1681
2832
3540
3363
5752
7168
4690
7965
9912
5487
9292
11593
7257
12124
14602
16638
25930
Static
Torsional
Stiffness
[lb in/rad]
532.8
1014
1521
2072
3042
5071
7606
10976
12673
18257
26355
20284
30426
38497
40568
63366
93279
55755
169920
244083
69472
197974
320370
84075
210630
366921
338070
557815
Dynamic
Torsional
Stiffness
[lb in/rad]
1593
3044
4540
6212
9115
15222
22833
32922
38019
54772
79065
60852
91278
115492
121705
190151
279837
128236
424800
610207
159786
494936
800925
193372
526575
917302
845175
1393875
Radial
Stiffness
[b/in]
874
1920
3452
4892
3326
6401
11487
16745
8458
14630
21123
10173
18288
24849
12430
25146
36999
13887
31833
41548
14745
33890
47286
17031
38210
52852
36679
49435
Complete Coupling, maximum
bore w/o kw
Weight
(lb)
Polar Moment
of Inertia J
(lb-in2) (x10-6)
0.098
57
0.306
374
0.621
965
1.178
3691
2.112
7485
8.324
40639
11.317
68782
16.993
135334
20.286
32.379
216825
477900
Curved Jaw Type
Lovejoy GS Series Curved Jaw Couplings
•
•
•
•
No backlash connections for use in machine tool applications.
Finished metric bores to H7 fit.
Clamp style and set screw style available.
Clamping design also available for use with shaft locking device.
CJ
Double Split Clamp Style Hub
Shaft Locking Device Hub
Single Slip Clamp Style Hub
Set Screw Style Hub
Dimensional Data [inches]
Size
14
19/24
24/32
28/38
38/45
42/55
48/60
55/70
65/75
Material
Aluminum
Aluminum
Aluminum
Aluminum
Aluminum
Steel
Steel
Steel
Steel
Max Bore
0.625
0.938
1.250
1.500
1.750
2.125
2.312
2.750
2.938
OD
1.18
1.57
2.17
2.56
3.15
3.74
4.13
4.72
5.31
OAL
1.38
2.6
3.07
3.54
4.49
4.96
5.51
6.3
7.28
LTB
0.433
0.984
1.18
1.38
1.77
1.97
2.2
2.56
2.95
G
0.51
0.63
0.71
0.79
0.94
1.02
1.10
1.18
1.38
CL
0.06
0.08
0.08
0.10
0.12
0.12
0.14
0.16
0.18
TH
0.08
0.12
0.12
0.16
0.16
0.16
0.16
0.18
0.18
Set Screw Style
Clamping Bolt Style
Set
Set Screw
Bolt
Screw
Location
Location
Torque
Size (SS)
(SL)
Bolt Size
(t)
(in-lbs)
8-32
0.20
M3
0.20
11.39
10-24
0.39
M6
0.47
92.93
10-24
0.39
M6
0.55
92.93
5/16-18
0.59
M8
0.59
221.25
5/16-18
0.59
M8
0.79
221.25
5/16-18
0.79
M8
0.79
221..25
5/16-18
0.79
M10
0.87
610.65
3/8-16
0.79
M12
0.98
1062.00
3/8-16
0.79
M16
1.26
2610.75
CJ-15
Curved Jaw Type
GS Series Hub Design (Descriptions)
CJ
The GS Series coupling features different hub designs for different application situations. Each type offers specific benefits for different types of applications.
The clamping styles offer the benefit of minimal to zero backlash.
Keyway With Set Screw
(KW)
Without Keyway,
With Set Screw
Standard Lovejoy method of securing
a hub to a shaft. Clamping style
recommended for backlash free
torque transmission.
Set screw used to secure hub to shaft.
This hub design should be used in
applications with non-reversing and
low torque characteristics.
Clamping Hub With Single
Slot Without Keyway (C)
Clamping Hub With Single
Slot With Keyway (CWK)
Zero backlash, clamping style for
torque transmission. Torque capacity
of hub depends on bore size.
Available standard for sizes 14-19.
Zero backlash, clamping style with
keyway for torque transmission. Usable
in applications featuring reversing loads.
Available standard for sizes
14-19.
Clamping Hub With Double
Slot Without Keyway (DSC)
Clamping Hub With Double
Slot With Keyway (DSCK)
Transmits torque utilizing a double
split clamp to attach hub to shaft. Zero
or minimum backlash. Torque capacity
of coupling determined by bore size.
Available standard for
sizes 19-65.
Transmits torque utilizing a double split
clamp to attach hub to shaft. Zero or
minimum backlash. Available standard
for sizes 24-65.
Hub With Frictional Locking
(LD)
This hub utilizes a shaft locking device
to allow for shaft engagement. This
design features bolts tightened on the
jaw side of the hub.
CJ-16
Curved Jaw Type
GS Series Misalignment Information
The GS Series coupling handles the following types of misalignment: axial, angular, and radial. The coupling
retains its zero backlash properties due to its spider design.
GS Series Misalignment Table
Axial Misalignment
Axial misalignment can be caused by
different shaft tolerances or by thermal
expansion of shafts. The GS Series coupling
handles axial misalignment while keeping
reactionary forces low.
Size
14
19
Radial Misalignment
Kr
Radial misalignment can be defined as a
measure of the offset distance between the
centerlines of the driving and driven shafts. This
type of misalignment, due to the forces
involved, causes the highest stress.
24
28
38
Angular Misalignment
Angular misalignment can be defined as a
measure of the angle between the centerlines
of the driving and driven shafts, where those
centerlines would intersect approximately
halfway between shaft ends. The GS Series
coupling can handle a specific amount of
angular misalignment for each given size (refer
to chart on right).
42
48
55
65
95
Axial
+0.039
-0.019
+0.047
-0.019
+0.055
-0.019
+0.059
-0.027
+0.070
-0.027
+0.078
-0.039
+0.082
-0.039
+0.086
-0.039
+0.102
-0.039
CJ
Misalignment
Spider
shore
80
92
98
64
80
92
98
64
92
98
64
92
98
64
92
98
64
92
98
64
92
98
64
92
98
64
Radial
0.008
0.006
0.003
0.002
0.006
0.004
0.002
0.001
0.005
0.004
0.003
0.006
0.004
0.003
0.007
0.005
0.003
0.007
0.005
0.004
0.009
0.006
0.004
0.009
0.007
0.005
Angular
1,1
1,0
0,9
0,8
1,1
1,0
0,9
0,8
1,0
0,9
0,8
1,0
0,9
0,8
1,0
0,9
0,8
1,0
0,9
0,8
1,0
0,9
0,8
1,0
0,9
0,8
0.007
0,9
CJ-17
Notes
BLANK PAGE
CJ-18