GB1573417A - Self aligning weighting element assembly - Google Patents

Abstract

The load arm (A) carries two driven rollers (RR, R') at one end and at its other end is supported on the housing (B, O), for example via a knife-edge mounting, in such a way that it is spherically pendulous about this point of articulation (O). The load arm is thus pivotable about a vertical axis, about a longitudinal axis and about a transverse axis. The load arm (A) is pressed via its rollers (R, R') against a drive body (D) by means of spring force (S). The free movability of the load arm (A) has hitherto been adversely influenced by this pressure force (S). In order to avoid this, a rolling body (K) is arranged between the pressure spring (S) and the load arm. The disturbing influence caused by spring deflection is prevented by this rolling body (K). The rolling body (K) is located in a U-shaped cap (HB) which is supported on the spring (S). The rolling body (K) rolls on the cap and on the load arm. <IMAGE>

Description

(54) SELF-ALIGNING WEIGHTING ELEMENT ASSEMBLY (71) We, NTN TOYO BEARING COMPANY LIMITED, of 25-banchi, 1 Chome, Kyomachibori, Nishi-ku, Osakashi, Osaka-fu, Japan, a Company organised and existing under the laws of Japan, and ZENZABURO TSUKOMO, of 7 of 11, Masumi-cho, Okeda-shi, Osaka-fu, Japan, a Japanese subject, do hereby declare the invention for which we pray that a Patent may be granted to us, and the method by which it is to be performed, to be particularly described in and by the following state ment: - The present invention relates to a selfaligning type weighting element assembly for use with a top-roller holding and pressing device which is important in forming a nip for draft operation in textile machines, including drawmg frames, flyer frames and spinning frames.

According to the invention there is provided in a pendulum arm type, self-aligning weighting arm assembly for use in textile machinery and having casing means, said casing means including a pivot member, weighting arm means pivotally mounted at one end to the said pivot means of said casing means for universal movement, rotatably driven roller means rotatably mounted on the opposite end of said weighing arm means, driving body means operatively positioned with said driven roller means for rotating same and pressing means operatively engaged with said weighting arm means intermediate the ends thereof urging said driven roller means into engagement with said driving means, the improvement of the pressing means which comprises cap means U-shaped in cross-section positioned in the lower end of said casing means for vertical movement therein, a rolling contact bearing element positioned within said casing means and between the bottom of said cap means and the top surface of the weighting arm means intermediate its ends thereof and in bearing engagement therewith, said rolling contact element being smaller than the width of the open end of the inverted U-shaped cap means for free rolling movement therein, and bias means positioned in said casing means and above said cap means positively urging said cap means against said rolling contact bearing element.

Weighting element assemblies according to the present invention may be arranged in a plurality of rows inside an enclosure, whereby they can serve as a device capable of performing the necessary weighting function for respective lines in a draft section.

Therefore, the invention has high versatility.

The present invention is described further with reference to the accompanying drawings in which, Figure 1A shows a front elevation in part section of a weighting element assembly according to the invention; Figure 1B shows a side elevation in part section of the assembly shown in Figure 1A; Figure 2A shows a front elevation in part section of another embodiment of the invention; Figure 2B shows a side elevation in part section of the embodiment shown in Figure 2A; Figures 3 to 8 are views showing various other embodiments of the present invention, being modifications of the general arrangements shown in Figures 1 and 2.

Referring to Figures 1A, 1B, 2A and 2B which show embodiments of the present invention, the general arrangement and structural concept of which will now be described; An arm A supporting a roller assembly R is pivotally mounted at one end about a support point 0. The other end of the arm A is biassed downwardly by a spring assembly 5 which freely contacts the upper surface of the arm A through a captive bearing ball K received within an end cap HB receiving the lower end of the spring S the upper end of which locates on a dimple 25 formed on the underside of a case B.

The inner surface XqY3' of the bottom end cap HB and the upper surface X5X5' of the guide arm case B are maintained in parallel relationship during operation.

At a predetermined position on the upper surface of the arm A opposed to a pressing body or pressing assembly, a rollingpurpose flat surface portion X2X2' is formed to provide a small guide surface.

The spring S is usually in the form of compression coil spring and its dimensions and spring characteristics are precisely prescribed in order to achieve the desired performance. The bottom cap HB is installed on the spring S in sueh a manner that the clearance with respect to the diameter of said spring (whether the inner or outer diameter) is minimized and at the same time it is combined with the guide arm case b (in some cases, the arm body) in such a manner that the fit clearance between the diameter (or width) d of the bottom cap HB and the widthwise inside dimension of the guide arm case is similarly minimized. As a result of this design. the vertical axis of the pressing spring S approximately coincides with the datum axis ZZ' of the width of the case.

Thus. this arrangement ensures that the spring S will be maintained upright at the predetermined position on the surface X5X5' of the guide arm case B, so that the axis of the spring S substantially coincides with the central axis of the width of the guide arm case B and hence the pressure exerted bv the spring acts vertically. In response thereto the ceiling surface X3X3' of the cap HB remains in parallel relationship with the surface X5X5'. so that through the pressing structure using the ball K contained in the bottom cap EE, the pressure of the spring S is transrni ed to the surface X2X2' of the guide arm B in the desired direction.

The roller assernbly R is driven by a driving roller assembly D and thus has a self-aligning action therewith whien is in turn relluxed by a self-aligning swing action ot .he arm A about the fulcrum 0. Consequently the rolling resistance of the ball K at its points of contact 27, 28 with the surfr. s X2X2' and X3X3' respectively is virtually eliminated. With regard to the parallelism of the upper and lower races XX' and X2X?' between the rolling element on bail K is interposed. some amount of tilt relative to each other away from parallelism carrot be avoided in practice.However, in the present system incorporating compensating means as described above, the relative tilt remains within a very small range and no lipage on the or ball contact or bearing surfaces occurs, since the pressure being transmitted acts to increase the resistance. In brief, one of the principle features of the present invention consists in the fact that the arrangement comprising a rolling element interposed between the bottom surface X3X3' of the pressing body and the upper surface X2X2' of the arm on the pressed side provides three different functions, namely, a rolling function, a pressure transmitting function and a function of eliminating the deviative pressure vector component of the pressing body between the bearing surfaces defined by the upper and lower parallel surfaces between which the rolling element is held.Thus, zero resistance to the self-aligning swing motion of the arm is maintained. even under high pressure, thereby improving the pendulum performance. As a result, a rolling support type pressing construction is achieved which responds to the restoration torque automatically produced on the arm with very high sensitivity, even under heavy load, whereby the pure pressure which does not interfere with the swinging action of the arm A is accurately transmitted to the top roller R.

In the draft section of the textile machine, the angle of swing of large amplitude employed in the existing weighting element assembly, is unnecessary and moreover, in most cases, superfluous swing is harmful.

Particularly in the large-size heavy-load weighting element assemblies employed in recent years, the excessiveness of the angle of swing is closely related to the departure from the parallelism of the top roller R, with respect to its contact surface.

The general arrangement of the invention will now be described in more detail with reference to various embodiments shown in Figures 3 to 8.

Figures 3, 4 and 5 show the relation between the cap HB holding the rolling element or ball K and the guide arm case B and also show various postures at points of contact 27, 28 between the rolling element K and the bottom cap HB and guide arm A.

Figure 3A shows a front view of the weighting element assembly and Figure 3B shows a side view thereof. In Figure 3A, a recess M is formed at a region of the arm A where the rolling body or ball K is pressed thereagainst. The configuration of the recess is such that, when viewed in the side view 3B, it is an arcuate groove having a radius R' somewhat greater than the radius R of the ball K, and that, when viewed in Figure 3A, it has a radius R equal to the radius R of the ball K. but with its center linearly displaced by a distance Ab so as to form a flat surface over the distance Ao.

Since the ball K rolls within this recess M, the horizontal swing of the arm A is performed in the range of said flat surface do, thereby making it possible to control the swing angle of the arm A. The portion of the ball K greater than its radius is received in the inside pocket of the cap HB with some clearance therebetween, so that there is no interference with the rolling of the ball K. Further, in the plane of the side view 3B, the design of the cross-section of the groove M does not allow the lateral displacement of the ball K, thus maintaining the contact point 27 on the datum axis ZZ'.

On the other hand, the cap HB is fitted in the guide arm case B with a minimum clearance therebetween and occupies a height h. As a result, there is obtained the function of compensating for the influence of the distortion or buckling tendency peculiar to the spring S.

The control of displacement of the ball K is controlled by the race groove M in the arm A.

Figure 4 shows a system in which the upper surface of the arm A is formed with a rectangular race groove M' for use as a race for the ball K. In this case, the amount of rolling displacement of the ball K is controlled by the dimension of the longer side a of the groove M, as shown in the frong view 4A. Further as seen in the side view 4B, since the race for the ball K has a groove width b, the ball K contacts the race at two edges 27 and 27', whereby the same operating condition as in Figure 4A is established.

Figure 5 shows a system belonging to preferred embodiments of the invention. As shown in the front view 5A, swing control projections 29, 29' are provided at particular positions on opposite outer surfaces of the arm A, in a spaced relation corresponding to the distance A5 shown in Figure 3A.

It becomes unnecessary to form a recess in the upper surface of the arm A, but the other conditions are generally the same as those of the system shown in Figure 3.

However, additional guide projections 30, 30', 31, 31' are disposed on opposite inner surfaces of the case B to surround the outer periphery of the cap HB, as shown in the plan view C in Figure 5, control the movement of the cap HB so that it moves only in the correct direction, i.e. in the direction of the pressing axis of the pressing spring without doing deviative actions in any other directions. This construction can be applied, without any change, to the embodiments shown in Figures 3 and 4. Figure 6 shows another embodiment concerning the rolling intermediary. As shown, this embodiment uses a shaft mounted roller K.

Figure 6 A, shows a front view and 6B shows a side view. Figure 6C is a perspective explanatory view. Figure 6D shows a weighting arm construction using a plate spring S' and a shaft-mounted roller K.

The system shown in Figure 7 is same as that shown in Figure 6 in that it uses a roller K, but the way the shaft of the roller is assembled is different from that shown in Figure 6. Thus, as contrasted with the system of Figure 6 having the shaft attached to the bottom cap HB, the system of Figure 7 has the shaft mounted in the upper surface of the arm A. Both the systems shown in Figures 6 and 7 have the advantage that the rolling element K, which is an intermediary, can be stabilized by the setting of the shaft and hence the swing action of the guide arm A is further stabilized. However, in some cases, such construction tends to become complicated and, on the other hand, simplification may cause some slippage. Nevertheless, some slippage does not matter too much and this system is convenient in cases where priority should be given to stabilization.

The embodiment shown in Figure 8 is an example of the so-called "universal type weighting arm" construction applicable to the various lines (front roller, 2nd roller, 3rd roller, etc.) in the draft section of a textile machine.

In Figure 8, the swing axis 0 for the arm A is located at the lower end of the guide arm case B. The other end of the arm A is provided with a knob 43 which is received on the lower edge of a rectangular opening 14 formed in the guide arm case. The arbor G of the top roller R is securely held by a central lower inverted U-shaped groove in the arm A. The opposite ends of a coil spring S are provided with a top cap 32 and a bottom cap 31 to form parallel surfaces at right angles to the central axis of the spring S extending along said opposite end surfaces.

The upper surface of the arm A is formed with a race for the ball K. TJ ually, in the race for the roller arrangerr.:1 , the center of the roller K is located on the datum axis XX' of the weighting element assembly so that the roller will not displace forwardly or rearwardly of the arm A, while á particular limit range is provided in the direction of swing. Thus, the arrangement is similar to those shown in Figures 3-5. More than the upper half of the ball K is received in the bottom cap 31 and its top is in contact with the upper under-surface thereof under pressure.

The bottom cap 31 and top cap 32 are fitted in the inner diameter of the spring S with a minimum clearance therebetween and their outer surfaces are fitted likewise in the case B with a minimum clearance therebetween, so that they are slidable only in the pressing direction. The upper assembly 36 of the case B forms an attaching base part for selectively fixing the weighting element assembly at a predetermined position on the weighting element assembly main body 42 and also serves as a base for adjusting a screw 35 which adjusts the pressure of the spring S.

As for the spring pressure adjustment, this embodiment shows a basic system using a screw and gauge plate 41, but this is an example only, since many methods may be used, including one using a stepwise adjustable top-shaped cam and one using a combination of a lever device and a cam device.

Therefore, the invention is not limited to the screw adjustment type. Further, pins 38, 38' illustrated are an example of means for uniting the upper and lower assemblies 36 and 37 of the case B. It is also possible to form them integral with the case B.

WHAT WE CLAIM IS: 1. In a pendulum arm type, self-aligning weighting arm assembly for use in textile machinery and having casing means, said casing means including a pivot member, weighting arm means pivotally mounted at one end to the said pivot means of said casing means for universal movement, rotatably driven roller means rotatably mounted on the opposite end of said weighting arm means, driving body means operatively positioned with said driven roller means for rotating same and pressing means operatively engaged with said weighting arm means intermediate the ends thereof urging said driven roller means into engagement with said driving means, improvement of the pressing means which comprises cap means U-shaped in cross-section positioned in the lower end of said casing means for vertical movement therein. a rolling contact bearing element positioned within said casing means and between the bottom of said cap means and the top surface of the weighting arm means intermediate its ends thereof and in bearing engagement therewith, said rolling contact element being smaller than the width of the open end of the inverted U-shaped cap means for free rolling movement therein, and bias means positioned in said casing means and above said cap means positively urging said cap means against said rolling contact bearing element.

2. A weighting arm as set forth in claim 1, wherein the rolling contact bearing element is a ball.

3. A weighting arm as set forth in claim 1, wherein the rolling contact bearing element is a roller.

4. A weighting arm as set forth in claim 1, wherein said cap means include means for controlling the effective rolling range of the rolling contact bearing element.

5. A weighting arm as set forth in claim 1, wherein the upper surface of the weighting arm includes a recess for controlling the range of movement of the rolling contact bearing element.

6. A weighting arm as set forth in claim 1, wherein the upper surface of the weighting arm includes an opening for controlling the range of movement of the rolling contact bearing element.

7. A high sensitivity self-aligning weighting element assembly as claimed in Claim 1 substantially as hereinbefore described with reference to, and as shown in any of Figures 1 to 8 of the accompanying drawings.

**WARNING** end of DESC field may overlap start of CLMS **.

Claims (7)

**WARNING** start of CLMS field may overlap end of DESC **. main body 42 and also serves as a base for adjusting a screw 35 which adjusts the pressure of the spring S. As for the spring pressure adjustment, this embodiment shows a basic system using a screw and gauge plate 41, but this is an example only, since many methods may be used, including one using a stepwise adjustable top-shaped cam and one using a combination of a lever device and a cam device. Therefore, the invention is not limited to the screw adjustment type. Further, pins 38, 38' illustrated are an example of means for uniting the upper and lower assemblies 36 and 37 of the case B. It is also possible to form them integral with the case B. WHAT WE CLAIM IS:

1. In a pendulum arm type, self-aligning weighting arm assembly for use in textile machinery and having casing means, said casing means including a pivot member, weighting arm means pivotally mounted at one end to the said pivot means of said casing means for universal movement, rotatably driven roller means rotatably mounted on the opposite end of said weighting arm means, driving body means operatively positioned with said driven roller means for rotating same and pressing means operatively engaged with said weighting arm means intermediate the ends thereof urging said driven roller means into engagement with said driving means, improvement of the pressing means which comprises cap means U-shaped in cross-section positioned in the lower end of said casing means for vertical movement therein. a rolling contact bearing element positioned within said casing means and between the bottom of said cap means and the top surface of the weighting arm means intermediate its ends thereof and in bearing engagement therewith, said rolling contact element being smaller than the width of the open end of the inverted U-shaped cap means for free rolling movement therein, and bias means positioned in said casing means and above said cap means positively urging said cap means against said rolling contact bearing element.

2. A weighting arm as set forth in claim 1, wherein the rolling contact bearing element is a ball.

3. A weighting arm as set forth in claim 1, wherein the rolling contact bearing element is a roller.

4. A weighting arm as set forth in claim 1, wherein said cap means include means for controlling the effective rolling range of the rolling contact bearing element.

5. A weighting arm as set forth in claim 1, wherein the upper surface of the weighting arm includes a recess for controlling the range of movement of the rolling contact bearing element.

6. A weighting arm as set forth in claim 1, wherein the upper surface of the weighting arm includes an opening for controlling the range of movement of the rolling contact bearing element.

7. A high sensitivity self-aligning weighting element assembly as claimed in Claim 1 substantially as hereinbefore described with reference to, and as shown in any of Figures 1 to 8 of the accompanying drawings.