March 27, 1956 T. A. DOURDEVILLE 2,739,366

Similar documents
United States Patent (19) Miller, Sr.

- F WEN N 42. Czz724,2 Zz-ssa 7ce. E. BY. Oct. 21, 1958 C. F. DASSANCE 2,856,797 3A 42. Filed June 1, 1953 INVENTOR.

(12) Patent Application Publication (10) Pub. No.: US 2007/ A1

Feb. 9, ,168,853 R. PRINCE HYDRAULIC CYLINEDER DEVICE. Filed Oct. 8, Sheets-Sheet l ~~~~ INVENTOR. 162/12e2 aga/2.

(12) Patent Application Publication (10) Pub. No.: US 2004/ A1

US 7, B2. Loughrin et al. Jan. 1, (45) Date of Patent: (10) Patent No.: and/or the driven component. (12) United States Patent (54) (75)

& 9. Š. Aerary 4. Morazzzzzok. May 19, : 1,538,208. INVENTORS INTERNAL COMBUSTION MOTOR. atz Aazzzz c1. A1arclaezzf H. A. NORDWICK E. A.

United States Patent (19) 11) 4,444,223 Maldavs 45) Apr. 24, 1984

(12) United States Patent (10) Patent No.: US 6,205,840 B1

W. Hope. 15 Claims, 5 Drawing Figs. (52) U.S. Cl , 5ll int. Cl... F16k 43100, F16k 5/14

/6/6 64. Oct. 14, , Vi: 2,613,753. Wa?ter C. Stueóira

June 6, ,987,128 W. KREG SOIL, DAMMING IMPLEMENT. Filed June ll, Sheets-Sheet. Werner Arieg INVENTOR. &&. ~~~~

(12) United States Patent (10) Patent No.: US 6,220,819 B1

United States Patent (19) Koitabashi

(12) Patent Application Publication (10) Pub. No.: US 2012/ A1

United States Patent (19) Kitami et al.

Az Z 1.357,665. Azzee/2Z27. Patented Nov. 2, y 24-cee?, A-6. vy

(12) Patent Application Publication (10) Pub. No.: US 2016/ A1

(12) Patent Application Publication (10) Pub. No.: US 2003/ A1

J, S, ROGERS, PADOCK, APPLICATION FILED MAY 15, 1915, 1,153,405. Patented Sept, 14, 1915, 2 SHEETS-S HEET i. 3-vi-ucvtot 21, 6)) 7/4-ee-d

(12) United States Patent (10) Patent No.: US 6,643,958 B1

(12) Patent Application Publication (10) Pub. No.: US 2014/ A1

May 19, 1964 AT TORNEY 3,133,451. R. J. THOMAs MULTIPLE REDUCTION GEAR UNIT. Filed Dec. 28, 196l. 3. Sheets-Sheet 1 R CHARD J.

(12) Patent Application Publication (10) Pub. No.: US 2002/ A1

(12) Patent Application Publication (10) Pub. No.: US 2007/ A1

Feb. 14, 1967 R. B. WENGER 3,304,094 CLIMBING WHEEL CHAIR A/C. Z. 5 is INVENTOR. a/caezo as a 7/gate, 57 d. 2. XO aoz. 1277aatavays.

(12) United States Patent (10) Patent No.: US 6,668,685 B2

(12) Patent Application Publication (10) Pub. No.: US 2012/ A1

N NE WTS 7. / N. (12) Patent Application Publication (10) Pub. No.: US 2003/ A1. (19) United States 17 N-M72.

(12) Patent Application Publication (10) Pub. No.: US 2011/ A1

USOO582O2OOA United States Patent (19) 11 Patent Number: 5,820,200 Zubillaga et al. (45) Date of Patent: Oct. 13, 1998

3 23S Sé. -Né 33% (12) United States Patent US 6,742,409 B2. Jun. 1, (45) Date of Patent: (10) Patent No.: 6B M 2 O. (51) Int. Cl...

CARBURETOR TYPE INTERNAL COMBUSTION ENGINE WITH PRECHAMBER Filed Dec. 8, a raasaara

(12) Patent Application Publication (10) Pub. No.: US 2017/ A1

(12) Patent Application Publication (10) Pub. No.: US 2014/ A1

(51) Int. Cl... B62D 25/00 flush with the end of the bed and the other edge overlapping

(12) Patent Application Publication (10) Pub. No.: US 2006/ A1. Lee et al. (43) Pub. Date: Mar. 9, 2006

United States Patent (19)

United States Patent (19) 11 Patent Number: 5,295,304

United States Patent (19) Muranishi

UNITED STATES PATENT OFFICE

III III III. United States Patent 19 Justice. 11 Patent Number: position. The panels are under tension in their up position

K7. ÎNTR 2,585,968. Feb. 19, 1952 H. SCHNEDER TURBOSUPERCHARGED INTERNAL-COMBUSTION ENGINE. Filed Feb. 2l, l944

United States Patent 19

Dec. 3, G. H. LELAND 1,737,595 ELECTRIC MOTOR W/a Av/2Ap. 2-2, 3 3 6AOAGAA. l. E/A/VD. 4772A/VAy

III. United States Patent (19) Barefoot 5,507,368. Apr. 16, Patent Number: (45) Date of Patent:

(12) United States Patent

(12) Patent Application Publication (10) Pub. No.: US 2014/ A1

United States Patent (19) Maloof

?zzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzz -! zzzzzzzzz,zzzzzzzzz. sssss?sssssss,! PATENTED JULY 21, PNEU MATIC SUSPENSION MEANS, J. H.

April 3, 1956 J. MONTANA 2,740,484 MOTOR DRIVEN STAIR CLIMBING HAND TRUCK

(12) Patent Application Publication (10) Pub. No.: US 2004/ A1

(12) Patent Application Publication (10) Pub. No.: US 2006/ A1

United States Patent (19) 11) 4,324,219

United States Patent (19)

June 25, 1968 ROTH 3,389,738 WINDOW SHADE APPARATUS FG. 2ASE. 4b. NVENTOR LEO ROTH. was 11- a-40, 2.11u1 2y 7. A2-2.1a-42a (arte?. ATTORNEYS.

(12) Patent Application Publication (10) Pub. No.: US 2006/ A1

United States Patent (19) Cronk et al.

United States Patent (19)

United States Patent (19)

1,702,475. Feb. 19, , F. FAHNG COIL WINDING MACHINE Filed June 27, sed. 3. Sheets-Sheet 1 INVENTOR WITNESSES: 6%s/fcA.

(12) United States Patent (10) Patent No.: US 9,035,508 B2

(12) Patent Application Publication (10) Pub. No.: US 2014/ A1. Durand (43) Pub. Date: Oct. 30, 2014 PUMP CPC... F04D 13/022 (2013.

March 16, ,173,402 W. D. CASSEL AUTOMATIC CATTLE SPRAYER. Filed Aug. 26, Sheets-Sheet l /WA70? WALTER D, CASSEL.

Phillips (45) Date of Patent: Jun. 10, (54) TRIPLE CLUTCH MULTI-SPEED (58) Field of Classification Search

Feb. 6, R, NSSM 2,368,998

United States Patent (19) Woodburn

United States Patent (19) Zebuhr et al.

(12) United States Patent (10) Patent No.: US 6,626,061 B2. Sakamoto et al. (45) Date of Patent: Sep. 30, 2003

(12) United States Patent (10) Patent No.: US 8,870,248 B2 Graute (45) Date of Patent: Oct. 28, 2014

(12) Patent Application Publication (10) Pub. No.: US 2012/ A1

United States Patent [19] [11] Patent Number: 4,542,882 Choe [45] Date of Patent: Sep. 24, 1985

(12) United States Patent (10) Patent No.: US 7,592,736 B2

(12) Patent Application Publication (10) Pub. No.: US 2011/ A1

(12) United States Patent

United States Patent (19)

US A United States Patent (19) 11 Patent Number: 5,531,492 Raskevicius (45) Date of Patent: Jul. 2, 1996

III. United States Patent (19) Saberton et al. III. 11) Patent Number: 5,161,424 (45) Date of Patent: Nov. 10, (75) 21 22) (51) 52 (58) (56)

Europaisches Patentamt (1 9) Qjl) European Patent Office. Office eurodeen des brevets (11) EP A2 (12) EUROPEAN PATENT APPLICATION

United States Patent (19) Smith

A Practical Guide to Free Energy Devices

(12) Patent Application Publication (10) Pub. No.: US 2010/ A1. (51) Int. Cl. of the spool. 20e /2-20s Z2 2 X XX 7

(No Model.) 3 Sheets-Sheet 1. A. A. DE LOACH. SAW MILL, No. 434,770, Patented Aug. 19, " -% -, -% (3-C 24-44/777-C- ATTORNEY.

(12) United States Patent

(12) Patent Application Publication (10) Pub. No.: US 2002/ A1

(12) Patent Application Publication (10) Pub. No.: US 2007/ A1. Cervantes et al. (43) Pub. Date: Jun. 7, 2007

US 9, B2. Stamps et al. Jul. 11, (45) Date of Patent: (10) Patent No.: (12) United States Patent (54)

United States Patent (19) Dasa

United States Patent (19)

March 31, a blue/raco Scarce, 2,278,181. /7%225 Zzeaf e2/7e22. Filed May 15, Sheets-Sheet l H. LEBERHERR ENGINE AND GEAR COUPLING

ZST 2G232Si2Si2G2G21

809,643. June 9, le A. E. SMALL RAILWAY CAR DROP DOOR

United States Patent (19) Smith

(12) Patent Application Publication (10) Pub. No.: US 2010/ A1

22-y 2 24, 7. -l- az. Z é - Jan. 26, 1971 D. F. webster 3,557,549 TURBOCHARGER SYSTEM FOR INTERNAL COMBUSTION ENGINE. is is a ST.

No. 858,740, :, PATENTED JULY 2, G, J, MEYER, SOAKLANKAPPARATUS APPLICATION FILED DEO, 22, 1805, 8 SHEETS-SHEET 1. 69tseviyoo: I.

United States Patent (19)

(12) Patent Application Publication (10) Pub. No.: US 2008/ A1

No. 801,373. PATENTED 00T, 10, J. E. GEARHART, ROTARY ENGINE, APPLIOATION FILED AUG, 2, HEETs-SHEET. Z2562/2ZZZ Aa27/2(272, inventor

3,136,172. June 9, Attorneys C. D. STRANG SHIFT MECHANISM FOR OUTBOARD PROPULSION UNITS. 2 Sheets-Sheet li

Transcription:

ROLL-DRIVING MECHANISM FOR A NAPPING MACHINE Filed Oct. 26, 193 4. Sheets-Sheet l K i Fi 9. ée INVENTOR, THEODORE A DOURDEVILLE, 4-y ATTY.

ROLL-DRIWING MECHANISM FOR A NAPPING MACHINE Filed Oct. 26, l93 4. Sheets-Sheet 2 U. S 22 W 2 S N %N2S 2. SS -St NS INVENTOR. THEODORE. A. DOURDEVILLE, 6% pay. f7falo&y ATTV

ROLL-DRIVING MECHANISM FOR A NAPPING MACHINE Filed Oct. 26, 193 4. Sheets-Sheet 3 INVENTOR. THEODORE A. DOURDEVILLE. e. fe-- ATTY.

ROLL-DRIWING MECHANISM FOR A NAPPING MACHINE Filed Oct. 26, 193 4. Sheets-Sheet 4 8lo We 82 84 Vio CDs CD 8 Fig a. 8 Fig b 8to We 82 eb WO 82 8 Fig.c 8 Fig.d INVENTOR. THEODORE A. DOURDEVILLE, gé.. was ATTY.

United States Patent Office 2,739,366 Patented Mar. 27, 196 2,739,366 ROLL-DRIVENG MECHANISM FOR A NAPPING MACHINE AND TORQUE CONTROL DEVICES THEREFOR Theodore A. Dourdeville, Holden, Mass., assignior to David Gessner Company, Worcester, Viass., a corpo ration of Massachusetts Application October 26, 193, Seria No. 388,141 S Claims. (C. 26-34) This invention relates to napping machines of the planetary type in which pile and counter-pile napping rolls are arranged alternately in a circular series in a rotated drum or carrier and engage the adjacent surface of a piece of cloth which is drawn at a definite speed through the machine. The napping surfaces of the rolls move in the same direction as the cloth but at such relative speeds as will produce a slight pull or a slight drag relative to the cloth, for pile and counter-pile napping effects. It is the general object of my present invention to pro vide a roll-driving mechanism and torque-control devices for a napping machine by which the napping action of the rols is made responsive to the torque applied to produce the desired mapping effect. A given torque applied to a cloth structure which offers a given resistance results in a particular roll speed. The net applied torque is controlled by the operator but the actual rotational speed of the rolls may vary as a consequence of the nature of the load. In the known prior art, the operator, on the contrary, selected a given roll speed which was thereafter approximately maintained and with but slight response to changes in load or operat ing conditions. To the attainment of this general object, I preferably provide a constant-volume-output pump, separate hy draulic motors for the two sets of rolls, and separate means to vary the effective torque of each motor by in creasing or decreasing the net operating pressure on said motor, and with said two motors operating substantially in parallel. In a modified construction, the motors operate in series in a substantially closed circuit, and a single pres sure-control device is provided. In a third form of the invention, provision is made for selective operation of the two hydraulic motors in either parallel or series relation. Mechanism may also be pro vided for automatically maintaining substantially con stant roll speeds during a continued napping machine operation. My invention further relates to arrangements and com binations of parts which will be hereinafter described and more particularly pointed out in the appended claims. Preferred forms of the invention are shown in the drawings, in which - - Fig. 1 is a sectional end view of a planetary type napping machine with certain parts omitted for clarity; Fig. 2 is a partial axial section, taken along the line 2-2 of Fig. 1; Fig. 3 is a diagrammatic view showing hydraulic con nections for independently controlling and driving the pile and counter-pile napping rolls respectively; Fig. 4 is a similar diagrammatic view showing the connections for controlling and driving the pile and coun terpile napping rollis at a fixed speed ratio but responsive to cloth-resistance; Fig. is a diagrammatic view showing additional valves and connections by which the two sets of rolls may be 0 2 30 40 4 0 60 6 70 2 operated independently, or a predetermined roll-speed ratio may be attained; and Figs. a to d indicate different valve settings to be ex plained. Referring to Figs. 1 and 2, I have shown parts of a plane tary type napping machine which is in general of com mercial form and which comprises a casing 20 in which a main shaft 1 is mounted in fixed bearings for con tinuous rotation at a uniform speed. A plurality of pile napping rolls R and counter-pile napping rolls R2 are alternated in a circular series in heads 12 fixed to the shaft is and rotated thereby. Each counter pile roll R2 is provided with pinion 20 (Fig. 2) which meshes with and is driven by a spur gear 21, and each pile roll R is provided with a pinion 22 meshing with and driven by a spur gear 24. In Fig. 2, the pinion 20 is shown as having twenty-five teeth and the gear 2i as having 221 teeth, while the pinion 22 is shown as having twenty-one teeth and the gear 24 as having 22 teeth. These gear ratios facilitate roll as sembly and are illustrative only. The spur gear 21 which drives the counter-pile napping rolls R2 is loosely mounted and has a pinion 30 asso ciated therewith which is engaged by a gear 32 driven by a commercial type hydraulic motor H2. The spur gear 24 which drives the pile napping rolls R has an ex tended hub or bushing 33 loosely mounted on the main shaft 1, and this hub is provided with a pinion 3 en gaged by a gear 36 corresponding to the gear 32 previously described and driven by a second and independent hy draulic motor H. (Fig. 1). The cloth C approaches the machine over a guide-roll 46 (Fig. 1) and then passes around a front feed roll 4. After substantially encircling the series of napping rolls, the cloth C then passes around a rear feed roll 42 and over a guide-roll 43 to suitable folding or other disposal mechanism (not shown). The feed rolls 42 and 42 are connected by pulleys 44 and 4 and a belt 46. They rotate at substantially the same surface speed but maintain a desired tension on the cloth. The belt pulley 44 has an associated gear 47 meshing with a pinion 48 which is connected by pulleys 49 and a belt 0 to the main driving shaft 11. The hy draulic motor H2 is supplied with liquid by a pump P which has a constant volume output. In the operation of the machine, the main shaft 1. rotates the heads i2, thus moving the circular series of napping rolls around a circlar path. The main shaft 11 is also connected as described to drive the cloth-engaged feed rolls 41 and 42 and thus passes the cloth through the machine at a predetermined rate which is coordinated with the travel of the napping rolls in their circular path. The net or resultant rotation of the counter-pile napping rolls R2 about their own axes is produced by the combi nation of the rotational movement of the head or carrier 12 and the action of the motor H2 through the gear 32, pinion 30, spur gear 2 and roll pinions 20. The rotation of the pile napping rolls R is similarly effected but in volves the motor H acting through the gear 36, pinion 3, spur gear 24, and roll pinions 22. The hydraulic connections by which the motors H and H2 are controlled and operated are shown diagrammati cally in Fig. 3, in which the constant-volume-output pump P is connected to the hydraulic motor H2 through a pipe having portions 0 and. The motor H2 is also pro vided with a discharge pipe 2 and with a pressure-regu lating relief valve V which is connected at the junction of the pipe portions 0 and as shown. A handle 4 is provided for manual setting of the valve V, and the valve V discharges through a pipe into the pipe 2 previously described. The pipe 2 is also connected into the junction of two

3 pipe portions 6 and 7. The portion 6 connects into a reducing valve V2 which may be permanently set for a desired back-pressure and which discharges to an open tank T. Pipe 7 is connected into the pile motor H, and this motor H discharges through a pipe 8 and a relief valve V3 to a pipe 9 connected to discharge into the tank T. A hand wheel 60 provides for manual setting of the valve V3. Considering now the counter-pile motor H2, it will be seen that the discharge or back-pressure in the pipe 2 is controlled by the valve V2 which is permanently set at any desired back-pressure, such as 100 p.s. i. As liquid is supplied by the pump Pat a constant voi ume output, the speed of the motor H2 will depend on the ratio of oil delivered to the motor and oil by-passed through the valve V to the back-pressure pipe 2. The motor pull and consequently the pull of the coun ter-pile napping rolls R2 is exerted against the resistance of the cloth during the napping operation. If this resist ance increases, the rolls and the hydraulic motor will slow down and an additional volume of oil will be by-passed through the valve V. Consequently, a substantially con stant torque or reaction to the cloth resistance is main tained. In the case of the pile napping rolls R, the pull of the cloth tends to increase the proportionate speed of the pile rolls and to make the motor H function as a pump, and with a braking rather than a driving action. Back pressure oil is supplied through the pipe 7, and the motor H, acting as a pump, discharges this oil at a higher pres sure which is determined by the pressure-regulating valve V3, now on the discharge side of the motor. Gauges G and G2 may be connected into the pipes 1 and 8, and operating conditions may be reproduced at any time by adjusting the valves V and V3 so that the same gauge readings are achieved. In the described con struction of Fig. 3, it will be noted that the oil discharged by both motors is returned to the open tank T. In the construction shown in Fig. 4, a normally-closed circuit is provided between the hydraulic motors H and H2, and in this combination also the motor H acts as a pump or brake. In this construction, the pump P dis - charges a constant volume output into a pipe 70 con nected to the intake of the motor H. A discharge pipe 71 connects the outlet of the motor H to the intake of the motor H2, and the discharge pipe 72 of the motor H2 is connected into the feed pipe 70 for the motor H. A single pressure-relief valve V6 is provided in the pipe 70 but adjacent the pump P, and the discharge pressure may be regulated by the hand wheel 73 as previously described. The valve V6 discharges into an open tank P2. With this construction, the pump P provides relatively low pressure through the pipe 70 for the motor H, and the motor H acting as a pump, supplies relatively high pressure oil through the pipe 72 to the motor H2. This motor in turn discharges through the pipe 72 at the lower pressure in the pipe 70. This lower pressure may be reg ulated by the valve V6, and any surplus output of the pump P will be discharged through the valve V6 to the tank T2. This construction will conserve power as the pile motor H. runs regeneratively but it is less flexible than the con struction shown in Fig. 3, as the motors H and H2 must rotate in fixed speed relation, and the pile and counter pile napping rolls must correspondingly rotate in a fixed speed ratio. The speed of the motors will be determined by the load or cloth-resistance, as in the previous con struction, but any change in the speed of the pile rolls must be associated with a similar change in the speed of the counter-pile rolls. In the napping of certain types of fabric, this fixed speed relation is not objectionable, and the pump P may operate at a much smaller delivery rate, as it merely main tains a relatively low pressure and replaces leakage. The arrangement shown in Fig. 3 is found most desir 2,739,866 O 20 3. 3 40 4. 60 6 4. able for relatively light napping operations on cloth of relatively uniform weight and texture, while the construc tion shown in Fig. 4 is somewhat better adapted for rel atively hard or heavy napping operations. In Fig., I have shown combined connections by which the machine may be made to operate with the motors H and H2 substantially parallel and independently adjustable, as in Fig. 3, or operating in a fixed speed rela tion as in Fig. 4. To attain this result, I have connected the pump P through a pipe 80 to a manually adjustable reducing valve V8, and I also connect the pipe 80 through pipes 81 and 81a to the motor H2. I insert a three-way valve V9 be tween the pipes 81 and 81a, and I also connect said valve V9 through a by-pass 82 to a similar valve V10 in the discharge pipe 84 of the motor H. The valve V10 is also connected through a pipe 8 and reducing valve V11 to atmospheric discharge. The discharge pipe 90 of the motor H2 is connected through a pipe 93 to the supply pipe 94 of the motor H, and a permanently adjusted reducing valve V12 connects the pipes 93 and 94 to atmospheric exhaust. By setting the valve V9 as shown in Fig. a and the valve V10 as shown in Fig. b, independent and torque controlled operation of each motor H and H2 may be O attained as in Fig. 3. By setting the valves V9 and V10 as shown in Figs. c and d, operation of the motors H and H2 will be in fixed speed ratio. If it is desired under certain conditions to operate the hydraulic motor H or H2 in Fig. 3 at a substantially constant speed rather than torque control, an automatic speed control device may be provided to adjust the hand wheel 4 in response to slight speed variations of the motor H2, and a similar device may be provided to similarly adjust the hand wheel 60 for the motor H. Such automatic devices have been found effective in holding speed variation to within one percent. The details of construction of these automatic devices constitute independent subject matter and are not herein claimed. The above-described roll-driving mechanism and torque control devices present important advantages in com mercial operation. In the construction shown in Fig. 3, each set of nap ping rolls is independently torque-controlled, and over travel of the cloth in either direction is easily prevented. Satisfactory operating conditions, once attained, are easily reproduced by adjusting the mechanisms to pro vide the same pressures on the gauges G and G2. With light or relatively weak materials or with knit goods which are easily stretchable, the effective torque may be correspondingly reduced and may be made al most neglible so that damage to such frail fabrics is effectively avoided. In the regenerative construction shown in Fig. 4, the operation of the two sets of rolls is definitely related, which is most desirable to meet extreme working condi tions. s While I have described mechanism which is primarily adapted to hydraulic operation, many of the described advantages may be attained with other types of power development. Having thus described my invention and the advan tages thereof, I do not wish to be limited to the details herein disclosed, otherwise than as set forth in the claims, but what I claim is: 1. In a planetary-type napping machine having a set rolls, in combination, a hydraulic motor to drive each set of rolls, means to supply liquid in constant volume output to said motors, means to regulate the supply pressure of the counter-pile motor, and means to regul late the discharge pressure of the pile motor. 2. The combination in a planetary napping machine as set forth in claim 1, in which the first regulating

means also provides a by-pass for excess liquid supply. 3. The combination in a napping machine as set forth in claim 1, in which cross connections provide for re generative operation of the pile motor, and manually operated valves provide selective determination of the type of operation. 4. In a planetary-type napping machine having a set rolls, in combination, a separate hydraulic motor for each set of rolls, a pump to supply a constant volume output of operating liquid for said motors, and connec tions through which said liquid operates to drive the counter-pile motor and to retard the rotation of the pile motor.. In a planetary-type napping machine having a set rolls, in combination, a separate hydraulic mctor for each set of rolls, a pump to Supply a constant volume output of operating liquid for said motors, connections through which said liquid operates to drive the counter pile motor and to retard the rotation of the pile motor, and separate means to control and maintain a selected net torque for each motor. 6. In a planetary-type napping machine having a set rolls, in combination, a separate hydraulic motor for each set of rolls, a pump to supply a constant volume output of liquid to said motors, and connections effecting closed circuit and regenerative operation of said two motors in series and in a fixed speed ratio. 2,789,866 16 20 2 30 6 7. In a planetary-type napping machine having a set rolls, in combination, separate driving means for each set of rolls, means to establish the net torque for each set of rolls, and automatic torque-maintaining means utilizing the pull on the cloth on the pile rolls and effective to vary the speed of each set of rolls inversely with respect to cloth resistance and to thereby auto matically maintain substantially uniform torque. 8. In a planetary-type napping machine having a set rolls, in combination, a separate hydraulic motor for each set of rolls, a pump to supply a constant volume output of operating liquid for said motors, connections through which said liquid operates to drive the counter pile motor and to retard the rotation of the pile motor, Separate means to control and maintain a selected net torque for each motor, devices to adjust said separate control means, and gauge means to indicate the adjusted pressures. References Cited in the file of this patent UNITED STATES PATENTS 62,843 Grosselin ------------- July 3, 1900 1986,746 Quick ---------------- Jan. 1, 193 2,120,76 Scholaert -------------- July 14, 1938 2,667,681 Langlois ------------- Feb. 2, 194