GUIDING SYSTEM

Abstract: A guiding system for guiding a slide (3) for movement along a guide means (1) that includes a longitudinally extending cavity (2) in which part of the slide is accommodated for guiding the slide in its movement in the guide means. At least three roller guides (11), for instance in the form of a roller-carrying band (16), are disposed along the cavity (2) in the guide means (1) and run between the slide (3) and the guide means (1). The system also includes a slide-coacting roller race (13) which is biassed towards the roller guide (11), and therewith towards the guide means (1), by a spring device (12).

Description: GUIDING SYSTEM The present invention relates to a guiding system of the kind defined in the preamble of Claim 1. Different types of guide systems are known in the art. A profiled slide is able to travel by sliding on guides. This type of system normally finds little use, and consequently ball-mounted guide systems have been developed in which the slide rolls on the guides with the aid of balls rotating in the slide. This construction is relatively complicated with respect to the slide and play or clearances cannot be avoided, and the construction generates a high degree of friction. An alternative to this type of system is one in which the slide rolls on guide-mounted roller guides. These guides have the form of a band that is provided with rollers and that has a length corresponding to half the length of stroke of the slide. Thus, as the slide moves, the roller guide rolls with the slide at half its speed. Even though the slide includes a guide-embracing profile, for holding the slide on the guide, play or clearance cannot be avoided, and this type of guide system cannot be used for work in a vertical direction, due to the fact that gravity and the aforementioned play or clearance prevents the roller guides from accompanying the slide movement. An unconditional requirement for faultless functioning of this type of movement mechanism is exact parallelism between the rolling surfaces of the guide and the slide. This requires exact tolerances and can be difficult to achieve, particularly in the case of mechanisms that have longer working strokes, where tolerances can vary and the precise straightness of the guide cannot be guaranteed, nor yet that the guide will not be twisted. The problems encountered with this latter type of guiding system are solved by the present invention with a slide guiding system that has the characteristic features set forth in the following Claims. The present invention will now be described in more detail with reference to an exemplifying embodiment thereof and also with reference to the accompanying drawing, in which Fig. 1 is a schematic, cross-sectional view of an inventive slide guide means and shows a slide movably mounted in said means; Fig. 2 illustrates an inventive guide means with a slide mounted externally of the guide means; Fig. 3 is a longitudinal sectioned view taken on the line III-III in Fig. 1; Fig. 4 illustrates very schematically the operational principle of the guide-slide assembly; Fig. 5 is a sectioned side-view of a roller guide; Fig. 6 shows the roller guide from above; Fig. 7 is a sectional view taken on the line VII-VII in Fig. 6; and Fig. 8 illustrates part of the roller guide. Fig. 1 shows a guide means extruded from light metal for instance and having a cavity 2 that extends along the full length of the guide and that is open upwards in the Fig. 1 illustration. A slide 3 whose shape corresponds to the shape of the cavity 2, an approximately triangular shape, can be moved reciprocatingly along . The slide has a neck which extends through the guide 1 and which carries a dogging element _4 intended for connection to a drive means, for instance. The guide cavity 2 of the illustrated embodiment includes four grooves 5, each of which faces towards said cavity 2 (reference is made in Fig. 1 to the upper right-hand groove in which no roller guide has been shown for reasons of clarity). The groove 5 includes three groove parts, wherewith the groove opens into the cavity 3 through a first groove part 6. A second part 7 of the groove is located immediately inwards of the groove part 6 and has a width which is greater than the width of the first groove part 6. A third groove part 8 is located inwardly of the second groove part 7 and has a width which is greater than the width of said second groove part. In the illustrated embodiment, the slide has a recessed portion 9 located opposite the first part of each groove 5. Inserted into the third groove part 8 is a steel band or strip 10 whose length corresponds generally to the length of the slide or the groove 5. As will be described in more detail here below, a roller guide 11 is mounted in the second groove part 7. The roller guide has a length which corresponds generally to half the length of an intended slide stroke. Mounted in the recessed portion 9 of the slide 3 is a supportive leaf spring 12 which extends along the length of the slide and which is arched in cross-section, as apparent from Fig. 1. Mounted on top of the leaf spring is a steel bar 13 whose length is equal to the length of the leaf spring. When the slide is fitted into the guide means, the upper side of the steel bar shall extend into the second groove-part 7 and there form a rolling surface for coaction with the rollers 14 of the roller guide 11. The steel bar 13 and the leaf spring 12 are held in position, for instance, with the aid of pins 15 mounted on respective ends of the steel bar 13 and extending through holes in respective leaf springs 12, down into holes provided in the slide 3, as apparent from Fig. 3. The steel bands and leaf springs are herewith locked against axial movement in the slide when the slide is fitted in the guide means . The leaf springs 12 function to bias the steel bar 13 towards the roller guides 11, which thus roll between the steel bands 10 and the steel bars 13 without slipping. At the same time as the slide 3 is guided in the guide means 1, in the absence of any play or clearance, the roller system will take-up any unavoidable deviations in parallelism and in fluctuations along the length of the guide means 1, in accordance with the inventive concept. Strings of resilient material, for instance rubber, may be used instead of leaf springs. Fig. 2 illustrates a guide-slide assembly which corresponds fully with the assembly described with reference to Fig. 1 in accordance with the concept of the invention, but which differs by virtue of the fact that the guide means 1 is, in this case, embraced by the slide 3. This means that the guide means 1 of the Fig. 2 embodiment does not include the cavity 2, although the arrangement in Fig. 2 functions in exactly the same way as the arrangement shown in Fig. 1. For the sake of clarity, the steel bands 10, roller guides 11, leaf spring 12 and steel bar 13 have been shown in only one of the four grooves 5 of the Fig. 2 guide means. It will be understood, however, that all grooves 5 accommodate these guide components, similar to the Fig. 1 embodiment . Fig. 4 illustrates the principle of the guide-slide assembly with the slide 3 travelling along the guide means 1 with the aid of the roller guides 11, the length of said guides corresponding to half the stroke length of the slide. The roller guide may comprise of rollers 14 which are accommodat- ed in elongated roller holders 16, made of nylon®, for instance. The length of the rollers 14 correspond to the widths of the steel bars 13, whereas the total width of the roller holders may be somewhat smaller than the width of the second groove-part 7, thereby ensuring that the roller guide 11 is retained in the guide means even when the slide 3 does not coact with the roller guides. The roller guide 11 is conveniently comprised of short, snap-in sections of rollers with roller holders, as schematically illustrated in Figs. 6 and 8. The outer parts of the roller holder section have the form of tongues 17 that are provided on their respective extremities with transverse pins 18. The tongues 17 at one end of a roller section are mirror-imaged in relation to the tongues at the other end of said section. This enables identical sections to be "snapped together" to provide roller guides of desired lengths. As will be apparent from the right side of Fig. 6, respective rollers may be replaced with mutually juxtaposed balls 14', in the illustrated case three such balls, without detracting from the desired function of the guide. Although the illustrated and described guide means includes four roller guides 11, it will be understood by the person skilled in this art that three such roller guides will suffice in principle for guiding the slide securely in the guide means. In this case, only one roller guide is required at the bottom of the guide means, centrally between the two upper roller guides shown in Fig. 1.

Claims: CLAIMS 1. A guiding system for guiding a slide (3) along a guide means (1) that includes longitudinally extending and generally oppo- sitely positioned grooves (5) for guiding the slide in said guide means, characterized in that respective grooves (5) accommodate a roller guide (11) in the form of a band (16) that carries roller bodies (14, 14') and that extends along the guide means (1) through substantially half the length of said guide means; and in that the system includes a roller race (13) which is biassed towards the roller guide (11), and therewith the guide means (1), by a spring force (12) that acts between the slide (3) and the roller race (13), said spring force being generated by a leaf spring (12) that has a slight U-shaped cross-section. 2. A system according to Claim 1, characterized in that respective grooves (5) are open towards the slide (3) as seen in cross-section, and include a first part (6), a second part (7) which is located inwardly of the first part and which is wider than said first part (6), and a third part (8) which is located inwardly of the second groove-part (7) and which is wider than said second groove-part; in that the third groove-part (8) accommodates a steel band (10) whose length is equal to the length of the groove; in that the second groove-part (7) accommo- dates the roller guide (11), whose length is equal to generally half the length of the groove (5); and in that the slide (3) is provided with a spring device ( 12 ) that extends generally along the full length of the slide in the first groove-part (6) of said groove (5); and in that a steel bar (13) whose length is equal to the length of the spring device (12) is mounted on top of said spring device and forms a roller race for the rollers (14, 14') of the roller guide (11) rolling on the slide (3). 3. A system according to Claim 1 or 2, characterized in that the roller race on the steel bar (13) is located in the second part (7) of said groove (5). 4. A system according to anyone of Claims 1-3, characterized in that the rollers of the roller guide (11) has the form of rollers (14) whose width is generally the same as the width of the steel bar (13); and in that the roller-carrying band (16) has a width generally equal to the width of the second groove-part (7). 5. A system according to any one of Claims 1-3, characterized in that the rollers of the roller guide (11) have the form of balls (14'); and in that the ball-carrying band (16) has a width generally equal to the width of a respective second groove-part (7). 6. A system according to any one of the preceding Claims, characterized in that the roller guide (11) is comprised of sections that can be snapped one into the other, so as to obtain a roller guide length that is adapted to the length of the guide means ( 1 ) .

Inventors: GRANBOM BO, GRANBOM, BO
Applicants: GRANBOM BO, KOLUNGEN AB, GRANBOM, BO
Application year: 1997
Main classification: F16C29
IPC codes: F16C29, F16C33