pyramid tent features

deflector type ball screw

0000009944 00000 n FIG. SANWA BUSINESS CREDIT CORPORATION 1 SOUTH WACKER, Free format text: However, the surface produced is rough, which decreases the efficiency and wear resistance of the ball screw due to the higher friction it will encounter. NEWSIDE DEFLECTOR Ball Screw AD Series, NEWSIDE DEFLECTOR Ball Screw AH Series. 432 0 obj <> endobj Example (2): The Internal Ball Return System used by Barnes Industries. Ball screws are more difficult to maintain than lead screws. 0000015650 00000 n 0000005994 00000 n FIG. Its operation relies on the sliding of the screw shaft and the nut threads with no ball bearings between them.

The key difference between ball screws and lead screws lies in their manner of transmitting loads. It is accomplished by using a spacer or a spring between two nuts, by using oversized balls, or by offsetting a lead. The initial or unadjusted radius of the bosses 60 is approximately 0.100 inch.

0000009665 00000 n PATENT RELEASE;ASSIGNOR:SANWA BUSINESS CREDIT CORPORATION;REEL/FRAME:008512/0367, Owner name: 0000024760 00000 n As the screw or nut rotates, the balls are deflected by the deflector into the ball return system of the nut and they travel through the return system to the opposite end of the ball nut in a continuous path. The return tube assembly is easy to install and dismantle. 0000023441 00000 n MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING, ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL, Gearings comprising primarily only cams, cam-followers and screw-and-nut mechanisms, Gearings comprising primarily only cams, cam-followers and screw-and-nut mechanisms for conveying or interconverting oscillating or reciprocating motions, Screw mechanisms with balls, rollers, or similar members between the co-operating parts; Elements essential to the use of such members, Screw mechanisms with balls, rollers, or similar members between the co-operating parts; Elements essential to the use of such members with balls, Screw mechanisms with balls, rollers, or similar members between the co-operating parts; Elements essential to the use of such members with balls with elements for guiding the circulating balls, GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS, TECHNICAL SUBJECTS COVERED BY FORMER USPC, TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION, ASSIGNMENT OF ASSIGNORS INTEREST. A traveling nut 18 is adapted to move axially along the screw, the nut defining an interior mating helical groove 20. This value can vary from one lead to another. The ball deflector of claim 8 wherein said deflector stem is integrally attached to said deflector body.

This article presents all the information you need to know about ball screws. 2 is a cross sectional view along lines 2--2 of FIG. During machining, to create the grooves, an offset is created in the lead, which is in the middle of a recirculation circuit. Multiple circuit ball nuts have two or more independent closed paths. %`vQ@9Jy=,swSIue0'G%}'#s-GF\tde9NMJeU DpVXWq;@Mn>.}~q066#di(ZQ!agk3id:He.LS9b=o#`4eAPFM#cTgm I It is a left-hand ball screw if the groove runs in a counterclockwise direction and it slants to the left. Ball grooves are also present in the internals of the nut that match the grooves of the screw shaft. An integral ball deflector stem 34 has an exterior threaded surface which receives a conventional threaded fastener 36 for retaining each deflector 30 rigidly within the groove 20 of the nut 18. BEAVER AEROSPACE & DEFENSE, INC., MICHIGAN, Free format text:

The nominal diameter, ball circle diameter, and root diameter are used in calculating the application characteristics and in sizing the screw. The unique element of ball screws is the ball bearings, which increase the power efficiency by minimizing the friction during the movement of the ball and nut. The arc in both profiles has slightly larger radii than the ball used. In a preferred form, the deflector body has two pairs of the locator bosses fixed to opposite sides of, and opposite ends of, the elongate deflector body. 0000025060 00000 n

NSK Ltd. (NSK; Headquarters: Tokyo, Japan; President and CEO: Toshihiro Uchiyama) today announced it has developed a new high-speed, low-noise deflector type ball screw tailored for European machine tool applications. Even more of a problem, however, is the fact that cumulative tolerance variations in deflector and nut groove sizing is such that rarely is there a satisfactory deflector fitment.

The deflector body 32 contains bevelled ends 48 adapted to deflect each of the circulating train of balls 22 which pass through the mating grooves, so that the balls pass out of the nut and into the transfer tube though the apertures 24. It is suitable for mass production and is more economic than internal recirculation systems. 0000009469 00000 n It is the minimum diameter of the screw shaft. The balls pass through an external tube that is protruding from the ball nuts wall. The bosses are adjusted by a grinder or other metal removal device to compensate for tolerance variations. 1). BEAVER PRECISION PRODUCTS, INC., MICHIGAN, Free format text: 6 which depicts a cross section of the body 52 taken through a pair of the bosses 60, those skilled in the art will appreciate that an upper body portion 62 is adapted to be seated in the prior art nut groove 20, while the lower body 64 is adapted to be received in the groove -4 of a conventional screw.

Referring now to both FIGS. Angles A are formed by the intersection of lines c--c and d--d which pass through the left boss 60, (located left of the vertical centerline b--b), and by the intersection of lines c-c and ee, the latter of which passes through the center of the right boss 60 (located on the right side of line b--b). mechanical kuroda screw ball suzin deflector method Ball screws may be categorized according to the mechanism of their ball recirculation. Referring to FIG. The bosses are semi-spherical in their preferred form. Those skilled in the art will appreciate the long standing practice of attempting to fit an elongate body of a deflector into a nut groove so as to cause the latter to be symmetrically seated and aligned within the screw groove. NEW SIDE DEFLECTOR Method ball screws A series, GW series (Grade C7) / GY series (Grade C10), Slide screws with resin nuts PW series (Grade C10) / PY series (Grade C10), Customized product Ultra-quiet ball screws FR series, Custom Tube Method Ball Screws / GR Series, Laminated Precision Press Tools for Motor Core, Precision Metal Press Products / Motor Core, C0 to C7 grades(C0 to C5 grades for ball screws with integral nut).

Ball screws use rolling and recirculating ball bearings in the ball grooves in the screw and the nut. This may be appreciated by those skilled in the art by reference to the cross section 2--2 of FIG.

The main components of ball screws are the screw shaft, the nut, and the ball bearings (or balls). In this type of screw, the lead is equivalent to the pitch. The lead of a screw is equivalent to the number of starts multiplied by the pitch. It is made by two intersecting arcs. The Industry Leader for Service & Product Integrity.

ball equipped ballscrews

Referring to FIGS. bk10 bf10 ballscrew sfu1204 floated mounts Ball screws have more complex structures and components and appear to be bulkier than other types of screws. The lead error is the difference between the theoretical and actual distance that the nut has traveled when the screw shaft has rotated. 0000005934 00000 n The higher number of starts has the higher linear distance covered in one revolution. The friction acting on the ball screw component is the rolling friction, which is relatively smaller compared to sliding friction. When tubes or caps are used to return the ball, they can be designed to create multiple independent circuits that are placed adjacent to each other. Call 248.541.2333 Today It is an important specification of a ball screw which determines linear travel and speed and load capacity. Galling is common in threads of nuts and bolts, threaded fasteners, and threaded inserts, including ball screws.

Deflector for ball screw and nut assembly, Assigned to BEAVER PRECISION PRODUCTS SUITE 3000, BEAVER PRECISION PRODUCTS SUITE 3000. This design is used for applications that require fine leads.

ball screw ballscrew thk screws motion drawing cutaway ballscrews nut components balls lead sbn linear recirculating threaded shaft

The improved ball deflector of the present invention provides at least one pair of adjustable locator bosses, each of the pair disposed on adjacent upper quadrants of the circumference of the deflector body. This solves the consequences of using higher leads.

3 is a cross sectional view along lines 3--3 of FIG. Ball screws are made from materials with high rigidity and stiffness such as stainless steel.

internal

The length of the return tube is supported by a tube holding bracket. The unique element of ball screws is the rolling balls in the helical groove which reduces the mechanical contact inside the screw assembly and replaces sliding friction with rolling friction. Referring now to FIG. Ball nuts are used in transmitting forces to a stationary or dynamic load with high accuracy, precision, and repeatability. End caps are mounted to guide the balls through a tunnel within the ball nuts internal; this directs them back to their starting point. Lead screws do not typically reach the torque conversion efficiencies of ball screws (around 90%). Ideally, the bosses are symmetrically positioned on the upper body in a manner such that the two equal angles A equal 10 to 25 degrees (FIG. These are used in many applications across many industries.

The complex design of ball screws adds up to its costs. The ball groove serves as the pathway for the rolling ball bearings. As Industry 4.0 and related initiatives continue to transform and advance the European market, NSK saw the need to develop and bring to market new deflector type ball screws, the most commonly used type in European machine tools.

SECURITY INTEREST;ASSIGNOR:BEAVER PRECISION PRODUCTS;REEL/FRAME:007251/0019, Owner name:

5.

Ball screws generate more noise than lead screws. They are used in medical equipment, food processing equipment, and laboratory machinery.

During securement of the stem to the nut by means of threaded fasteners, manufacturing tolerances tend to give rise to an objectionable amount of cocking or shifting (about the stem axis) of the deflector body within the groove. 0000024021 00000 n 0000015819 00000 n 0000004239 00000 n The ball bearings, or the balls, are the most prominent component of the ball screws that moves between the clearance of the nut and the shaft. This method is used for setting a large preload. internal Disposed within the mating grooves 14, 20 of nut and screw, for providing relatively frictionless rolling contact therebetween, are a plurality of ball bearings 22 (hereinafter referred to as balls). During assembly, the bosses 60 are adjusted by an electric grinder or other metal removal means to assure satisfactory deflector alignment with the nut groove. 0000006433 00000 n 0000010364 00000 n website require registration.

A substantial improvement would result if there were provided a mechanical means to alleviate or minimize such movement during fit-up of the deflector body within the nut groove. PATENT EXPIRED DUE TO NONPAYMENT OF MAINTENANCE FEES UNDER 37 CFR 1.362.

0000009264 00000 n 0000035124 00000 n Backlash is the lost motion caused by the clearance between the ball and the nut and screw tracks.

Ball screws have a higher load capacity than lead screws. FIG.

It can disrupt the accuracy and repeatability, which are required for precise positioning applications. 0000027562 00000 n

It avoids the premature breakdown of the ball screw and increases its performance by lowering the coefficient of friction and by minimizing the heat build-up resulting from the motion of the ball screw components. Call today! 0000015877 00000 n visit our faq page for more information. Therefore, the number of turns is always equal to the number of circuits for internal ball return systems.

;ASSIGNOR:SCHLENKER, THEODORE R.;REEL/FRAME:005248/0555, Owner name: This is where a rotating ball nut design is needed. However, for convenience, the view of FIG. 0000000016 00000 n

ASSIGNMENT OF ASSIGNORS INTEREST. Circuit refers to the closed path in the recirculating system of the ball nut. 0000011201 00000 n <>/ExtGState<>/Font<>/ProcSet[/PDF/Text]>>/Length 17 0 R 0000024483 00000 n In spring preloading, a spring is placed between two ball nuts that transmit the preload. The contact points of the ball between the screw shaft and the nut are distinguished by the groove profile of the two components where the ball touches.

Ball screws are mechanical linear actuators that consist of a screw shaft and a nut that contain a ball that rolls between their matching helical grooves. Preload is applied by assembling larger ball bearings. 1. In the assembly 10 as shown, three such tubes 26 are utilized, hence there are three trains of bearing balls adapted for circulation through the cooperating grooves between the screw and nut.

0000023739 00000 n Standard Ground Ball Screws / DP Series: Accuracy grade C3. Referring now to FIG. The common groove profiles are the gothic arc and the circular arc: This is the most common groove profile. Assigned to BEAVER PRECISION PRODUCTS, INC. Assignors: SANWA BUSINESS CREDIT CORPORATION. 1 is a fragmentary plan view of a prior art ball screw and nut assembly of the type in which a preferred embodiment of the deflector of present invention may be utilized. The ball screw is identified as a right-hand ball screw if the groove is traced in a clockwise direction around the screw shaft and slants to the right. 1.

Assigned to SANWA BUSINESS CREDIT CORPORATION 1 SOUTH WACKER, SANWA BUSINESS CREDIT CORPORATION 1 SOUTH WACKER.

Consequently, upon tightening the threaded fastener 36 on the stem 34 during assembly, the elongate body 32 is often rotated about the axis a--a of the stem, resulting in deflector ends 48 which are not aligned with the nut groove.

The accuracy of ball screws is improved by preloading, lubrication, and increasing the mounting accuracy. 2 will be treated as a single one of the three continuous or endless trains of balls 22. In a preferred form, the ball deflector is mounted within the nut of a recirculating ball screw and nut assembly, the deflector having an elongate body adapted for cooperation with balls moving within a ball passage formed by a segment of cooperating helical grooves in the screw and nut. UNITRON INCORPORATED, TEXAS, Free format text: 8. SECURITY INTEREST (SEE DOCUMENT FOR DETAILS). 4. This clearance is unwanted because it causes backlash. However, this mechanism produces the smallest preload and is suitable in applications where precision is not that crucial. 0000013741 00000 n 4. 0000035021 00000 n +7W.~\c]0:8rA@'%uvi=(PGx1W(\9x6 W3l'g =]J+m`f3[ .tkbM }V:5x>[j(J4( 0T$f%a=@P97]DX,4)]2[O: This design is ideal for high lead ball screw applications because it can endure the force from the fast-moving balls. %PDF-1.6 %

0000003585 00000 n A threaded stem fixed to the deflector body secures the body to the nut, the stem being operative to maintain the body fixed relative to the nut by means of a conventional threaded fastener. 0000003896 00000 n

The nut houses the ball bearings and their recirculation mechanism.

However, these screws differ in many aspects. The two deflectors located at the opposite ends of the nut 18 each employs only one of its two bevelled ends 48, as will be appreciated by those skilled in the art. The screw shaft is the component of the ball screw that receives rotational force for it to rotate about its axis; this is translated to linear motion.

3. 0000010128 00000 n We will discuss their important specifications and their impact on the operation. The ball deflector of claim 9 comprising a solid precision cast member. This system can support fine lead ball screw assemblies and a wide range of screw shaft diameters. The power to rotate the shaft is supplied by a motor, which is situated on its end. The auxiliary components supporting the ball screw must be mounted precisely to improve accuracy. 500 0 obj<>stream endstream endobj 433 0 obj<> endobj 434 0 obj<> endobj 435 0 obj<>/ColorSpace<>/Font<>/ProcSet[/PDF/Text]/ExtGState<>>> endobj 436 0 obj<> endobj 437 0 obj<> endobj 438 0 obj<> endobj 439 0 obj<> endobj 440 0 obj[/DeviceN[/DIC#202591p]/DeviceCMYK 491 0 R] endobj 441 0 obj[/Separation/DIC#202591p/DeviceCMYK 476 0 R] endobj 442 0 obj<> endobj 443 0 obj[/DeviceN[/DIC#202591p]/DeviceCMYK 494 0 R] endobj 444 0 obj[/DeviceN[/DIC#202591p]/DeviceCMYK 489 0 R] endobj 445 0 obj[/DeviceN[/DIC#202591p]/DeviceCMYK 484 0 R] endobj 446 0 obj[/DeviceN[/DIC#202591p]/DeviceCMYK 475 0 R] endobj 447 0 obj<> endobj 448 0 obj<> endobj 449 0 obj<> endobj 450 0 obj<> endobj 451 0 obj<> endobj 452 0 obj<>stream NSK Ltd.CSR Division HeadquartersPublic Relations Department, Contributes to improved productivity of machine tools. As the lead of ball screws increases, the linear distance covered and the speed increase. 0000028484 00000 n

Ball screws have higher efficiency, speed, accuracy, and load capacity, making them useful in a wide range of industrial applications.

DANA CORPORATION, OHIO, Free format text: %

0000023543 00000 n <<247999CCFF4C954492059C9C96B9611E>]>> Tensional forces are applied on two adjacent sides of the ball nuts due to the spring force. This is known as a cross-over deflector type internal return system.

0000009848 00000 n 0000006497 00000 n

The aforedescribed embodiment has an overall vertical height of approximately 0.6 inch and was designed for a ball screw assembly which utilizes 5/8 inch diameter balls. The ball screw assembly consists of a screw and a nut, each with matching helical grooves, and balls which roll between these grooves providing the only contact between the nut and the screw.

1 from which FIG. 0000004711 00000 n

9. The ball recirculation system in the nut allows the balls to be "recycled" in the operation by returning them to their starting point in the circuit. With this profile, the ball has two contact points on the screw shaft and two contact points on the nut. Ball screws produced using this method have high precision but are more expensive and are produced slowly. In a ball deflector for a recirculating ball screw and nut assembly, said deflector including an elongate body adapted for placement within a ball passage formed by a segment of cooperating helical grooves in a screw and a nut, said nut being movable along said screw, said deflector defining a body, a stem fixed to said body and adapted for securement of said body to said nut, said stem operative to maintain said body fixed relative to said nut; an improvement comprising said body including at least a pair of adjustable locator bosses disposed for engaging the groove of the nut, each boss disposed in adjacent quadrants on the circumference of said body. Screws typically have one, two, or four starts.

The ball deflector of claim 6 wherein said radius of said upper body comprises approximately 35 to 50% of said ball diameter.

The ratio of the number of threads in the ball nut circuit to the number of threads on the ball screw determines how much sooner the ball nut will reach fatigue failure (wear out) than the ball screw will. FIG. Each ball deflector 30 has an elongate body 32 retained within the mating helical grooves of the screw and nut.

0 However, this preload mechanism creates longer leads, which reduce the load capacity of the ball screw. The uncut blank shaft is passed through rotating tool dies to form the grooves. The deflector 50 incorporates an elongate body 52, wherein a threaded stem 54 is rigidly affixed to the body 52, preferably integral therewith. The efficiency of screws is measured by their capability to transform power utilized in exerting rotational force to the linear distance covered. A major drawback with the aforedescribed approach, however, is in its fitment limitation to a singular groove-ball size. ;uYm]}C3t,eER"Fj6HJ ge^, 4Ff+;-tX^TgXq5&/T}LW_{=Y7&SPSDmo-_zu$(Ep8Lb@n,.^r%qKFT F/,~`90/..0xD%$h?T*;=~ Hr#C L+~|]k(.1s8}e.\\(PRx9^O:lyyO~rJ>&8U.uITa Tz]~G2 %w "H5T PJ>&3sCy:VuJ kESj,Z]V[# 6[wz0B$RjIzmK]%WK) 'W#_Ys ydm RU/E 20~~-*sA~#G PN| ]}p}+R$0Z@ bxR}S_

% Xh@o?,zZf4DSPk2H 0'q:h=F K2"iCr"O jnG9qNJbB#*l5gMOk6.

The two groove profiles differ on the contact points they touch on the ball. As will be appreciated, the adjustable bosses 60 offer a greater flexibility in accommodating tolerance variations. As is typical of the latter construction, the lower body portion 40 is formed to provide greater clearance from the sides of the mating groove 14 of the screw for accommodating axial and radial movement or lash in the screw relative to the nut to avoid binding of the screw on the deflector member. ASSIGNMENT OF ASSIGNORS INTEREST (SEE DOCUMENT FOR DETAILS).

The ball deflector of claim 1 wherein said deflector body comprises two pairs of said locator bosses fixed to opposite sides of, and at opposite ends of, said elongated body. Comparison of ball screws and lead screws.

It preserves the efficiency of the ball screw by keeping contaminants and foreign materials from entering the clearance between the ball and the nut; it also retains the lubrication of the ball screw assembly.

The pitch refers to the distance of two consecutive threads, while the lead is the linear distance covered in one complete rotation. 0000005874 00000 n You can serch for a ball screw by the combination of screw shaft diameter and lead. Ball screw and nut assemblies include deflectors for the purpose of ensuring efficiency of ball transfer between return tubes and associated ball passages formed by helical grooves provided in the screw and nut. 0000026177 00000 n

The purposes of preloading are to increase the rigidity and to eliminate the backlash of the ball screw assembly. Lead screws, like ball screws, serve a similar purpose to mechanical linear actuators that translate rotational motion to linear motion. The screw shaft is the component that receives the rotational force. The ball groove profile of a ball screw may either be a semi-circular arc or a gothic arc.

432 69 The spacer applies force on the adjacent sides of two ball nuts; this force is transmitted to the nut and the grooves. 2, while appearing to show one of the three loops, actually depicts partial views of two separate loops.

2. The balls are usually made from steel. In this type of return system, the ball is returned to the opposite end of the circuit through or along the nut wall, but below the outside diameter through a "V" cap. The bodies are generally semi-cylindrical, the upper body having a greater radius than the lower. The ball is in contact with the screw shaft and the nut. 0000010216 00000 n Lead screws have deeper helical threads in the screw shaft and a matching nut that slides with each other. 4. 1, a prior art recirculating ball screw and nut assembly 10 is shown fragmentarily. The ball deflector of claim 7 wherein said bosses are semi-spherical, each having an initial unadjusted radius of approximately 0.100 inch.

To summarize, ball screws are valued for their power efficiency, accuracy, precision, and load capacity.

Pitch is the axial distance between two adjacent threads. Meanwhile, lead screws are used for transfer applications where speed, accuracy, and precision are not of high priority. Linear slides, also referred to as linear guides or linear-motion bearings, are types of bearings that allow smooth and near-frictionless motion in a single axis.

Heat causes the thermal expansion of the components and negatively affects the accuracy of the ball screw.

Example (3): The Tangential Internal Ball Return System used by Barnes Industries. The deflector typically includes a threaded stem fixed to the deflector body for securement of the body within the groove. To the extent that there is a slight offset between the two centers 68 and 70, the upper and lower body portions are symmetrically joined together by a portion having exterior contours which are tangent to the lower body 64. Fingers are fixed on the endings of the return tube to guide the balls in entering and leaving the return tube. Barnes Industries engineering department has developed various rotating ball nut designs. 6). The nut of a ball screw is a cylinder that houses the ball bearing and its recirculation system. The ball screw consists of a screw and nut with matching grooves and ball bearings that move between them.

When using, the screw shaft supported end may need additional machining in accordance with the conditions of use. 4 is an elevational view of a preferred embodiment of the ball deflector of the present invention. NSK will exhibit this ball screw, and other innovations for Industry 4.0, in Germany, at EMO Hannover 2017, from September 18 to 23.

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deflector type ball screw