JPS6238116B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to polishing equipment, and more particularly to pad assemblies for vacuum rotary disc sanders.

Several embodiments of a double-acting vacuum polishing apparatus are described in co-pending application Ser. No. 240,516, filed Nov. 26, 1975. The present invention relates in particular to a pad assembly for a rotary vacuum-operated disc sander, although the device for driving the disc and the vacuum generator for the disc assembly are disclosed in the aforementioned Patent Application No. 240,516. It may be the same as that described in .

The rotary sander rotates at a fairly high speed,
It is also used for grinding work and strong machining such as car bodies. Due to the varying nature of the process and the materials to be sanded, it has been difficult to obtain effective rotary sander assemblies equipped with vacuum equipment to date. This was primarily due to the fact that the abrasive particles clog the small passages in the disc, especially when the pad is bent under pressure.

The present invention comprises a flexible pad body secured to a rigid head member, the rigid head member being provided with a vacuum rotary sander such as may be connected to the pneumatic rotary device described in the aforementioned patent application Ser. No. 240,516. The invention thus overcomes the deficiencies of the prior art. Additionally, the rigid head is surrounded by a vacuum housing as shown in the aforementioned patent application Ser. can do. A plurality of holes in the head member communicate with other holes in the underside of the pad through internal grooves in the pad body, and the holes are formed at an angle toward the direction of rotation of the pad so that the pad The leading action of the vacuum function is applied to the hole when the hole is rotated. The holes in the lower portion of the pad are aligned with the holes in the abrasive disk removably secured to the pad assembly. Also, in a preferred version, the holes in the lower portion of the pad are elongated in a direction opposite to the direction of rotation, so that the holes in the abrasive disc and pad assembly are not misaligned with respect to the pad assembly. The grinding disk is made to slide to some extent.

According to one aspect of the invention, there is provided a pad assembly for a vacuum rotary sander, the assembly having a circular upper pad portion made of a stiff but resilient material; a plurality of holes arranged in this part so as to share a center with this part and spaced at uniform intervals approximately halfway between the center of the upper pad part and the outer periphery of this part; and an elongated groove extending outwardly from each of the holes at an angle in the direction of rotation of the pad assembly, each of the grooves being open at its lower side to allow the pad assembly to rotate. The body further has a lower pad portion made of a relatively soft and flexible material, the lower pad portion being uniformly spaced within and centrally connected to the portion. an inner row of holes and an outer row of holes arranged so as to share a plurality of holes, and the inner row of holes provided in the lower pad portion are aligned with the holes provided in the upper pad portion. The lower pad portion is configured to form inner vacuum holes and such that the outer row of holes in the lower pad portion are aligned with the outer ends of the grooves in the upper pad portion. The material of the lower pad portion, which is adhered to the upper pad portion and is intermediate the inner row of holes and the outer row of holes in the lower pad portion, has flexibility in the groove. forming a bottom wall, the upper pad portion having an inwardly and upwardly tapered peripheral side wall with a groove adjacent the upper end thereof; The abrasive disc is adapted to receive an abrasive disc on its lower surface, the abrasive disc being secured to the side wall by means of a resilient retaining device with holes in the disc aligned with apertures in the lower pad portion. The pad assembly is adapted to be retained by a flexible backing member retained within the groove, and the pad assembly is further adapted to be centered over the upper pad portion. a circular rigid head member adapted to be coupled to a commonly fixed and rotating vacuum device;
A vacuum rotary sander pad assembly is provided in which the head member has a plurality of slightly larger holes aligned with the holes in the upper pad portion.

Another aspect of the invention is a vacuum abrasive assembly having a circular pad and an abrasive disc attachable to the pad, the pad and abrasive disc having abrasive material therein. into the abrasive assembly, the abrasive assembly having means for positioning and mounting the abrasive disk on the pad, the apparatus having a circular flat surface. There is a member having an upright primary pin disposed in the center of the member and adapted to align a hole in the center of the abrasive disc and pad, and an inwardly tapered outer surface. an upstanding side wall having a lip attached thereto and retaining an O-ring at the upper end; and at least one pair of spaced apart secondary pins fixed to and upright from a flat surface. A vacuum polishing assembly is provided, the secondary pins corresponding to a selected pair of aligned holes in the polishing disc and pad.

Next, embodiments of the present invention will be described with reference to the accompanying drawings.

Referring to FIGS. 1 and 2, pad assembly 10 includes a circular lower pad portion 11, an upper pad portion 12, and a head member 14. Referring to FIGS. In FIG. 1, the lower pad portion 11 is shown as a single sheet constructed of a relatively soft, flexible material such as rubber and having a plurality of inner holes 16 and outer holes 18 in its surface. . The direction of rotation of pad assembly 10 is indicated by arrow R. The inner row of holes 16 are located approximately midway between the central hole 58 of the lower pad portion 11 and its outer peripheral edge, and the outer row of holes 18 are located more or less adjacent the outer peripheral edge of the pad assembly 10. It is located. The inner row of holes 16, like the outer row of holes 18, are circumferentially evenly spaced from each other. Holes 16 and 18 may be circular, but are preferably elongated as shown.

In FIG. 1, the upper pad portion 12 is positioned over the lower pad portion 11 as shown in FIG.
6 and 18 are provided with a groove 20 interconnecting them. In the upper part of Figure 1, the position occupied by the groove 20 is shown in phantom lines, and in the central part of Figure 1, which shows the top surface of the upper pad part 12, the inner row of holes 16 and the outer row of holes 16 are shown. An elongated groove 20 is shown communicating with the hole 18. The radially inner end 22 and the radially outer end 24 of the groove 20 are
When the upper pad portion 12 is placed over the lower pad portion 11, the inner row holes 16 and the outer row holes 1
8, respectively.

The upper pad part 12 is constructed from an elastic material that is extremely stiff compared to the material of the lower pad part 11.

The head member 14 is constructed of a rigid material and is shown partially omitted in FIG. Head member 14 has a hole 26. Hole 26 is formed into groove 2 when head member 14 is adhesively bonded to the top surface of upper pad portion 12, for example, as shown in FIG.
0 and the inner row holes 16 of the lower pad portion 11. The holes 26 in the head member 14 are preferably slightly larger than the holes 16 with which they overlap, and the holes 26 are preferably elongated as shown in FIG. The head member 14 also includes a threaded central sleeve 28 for coupling with a suitable rotation device.

Referring to FIG. 2, a partially cutaway top view of pad assembly 10 shows the communication path between outer row holes 18, grooves 20, inner row holes 16 and holes 26 in head member 14. Inner row holes 16 and outer row holes 18
extends in a direction away from the direction of rotation R, so that the outer row holes 18 have a leading portion 30 and a trailing portion 32, and the inner row holes 18 have a leading portion 30 and a trailing portion 32; It will be apparent that the bore 16 has a leading end 34 and a trailing end 36.

The reason for the leading and trailing ends in holes 16 and 18 is that when an abrasive disc having a hole therein is aligned with the hole in pad assembly 10, the abrasive disc is attached to the underside of the pad assembly. the torque exerted on the abrasive disc by the surface being ground and held by a flexible skirt and an elastic retainer on its underside, caused by the operator applying significant pressure to the abrasive disc; This is because slippage often occurs between the surface of the abrasive disk and the support pad assembly 10 due to its size. Because the holes 16 and 18 are elongated and have leading and trailing ends, the abrasive disk can slide a substantial amount rearwardly through the holes 16 and 18 while still remaining in the outer row of holes 18. It will be appreciated that it communicates with the rear end 32 and the rear end 36 of the inner row holes 16.

Also, from FIG. 1 and FIG. 2, the outer row holes 18
are offset circumferentially from the inner row holes 16 and the grooves 20 interconnecting these holes 16, 18 are oriented at an angle relative to the direction of rotation R of the pad assembly 10 and It will be noted that the addition of a pad can increase its effectiveness in collecting abrasive sand when the pad is rotated at high speeds.

Referring to FIG. 3, although the upper pad portion 12 can be constructed from a single disc member, Applicants have constructed it into two discs, namely the upper disc 12.
It is considered preferable to consist of the lower disc 12b and the lower disc 12b. The upper disc 12a is constructed from a very hard, elastic material, and the lower disc 12b is constructed from a softer and more flexible material. In either case, upper pad portion 12 has holes 1 aligned with holes 26 in head member 14 and holes 16 in lower pad assembly 11.
It has 3. From Figure 3, upper pad part 12
provides upper and end walls to groove 20, and inner row holes 16 and outer row holes 18 of lower pad assembly 11 provide flexible bottom walls to groove 20; will be understood. Therefore, in cross section, the groove 20 has two inlets 18 and 1
6 and large discharge ports 13 and 26.

Abrasive disk 38 includes a flexible backing 40 . Backing material 40 is adhesively secured to abrasive disk 38 and includes a flexible circumferential skirt 42 . The skirt 42 is folded into a groove 44 in the side wall of the upper pad assembly 12 and is fitted with a directed taper and a resilient O-ring or other suitable retention device against the side wall as shown in FIG. It is held in place.

The abrasive disc 38 has an inner row of holes 46 and an outer row of holes 48, and from FIG.
8 is attached to the lower surface of the pad assembly 11,
Hole 46 in the inner row is hole 1 in lower pad assembly 11.
6, aligned with holes 13 in upper pad assembly 12 and holes 26 in head member 14, while abrasive disc 38
The outer row of holes 48 are the holes 1 in the lower pad assembly 11.
8.

The present invention also provides a mounting system 50 for quickly and accurately positioning and attaching the abrasive disc 38 to the underside of the pad assembly 10. Mounting device 50 has a circular, flat platform or surface 52 with a central pin 54. The central pin 54 is adapted to align with the central hole 56 of the abrasive disc 38 and the central hole 58 of the pad assembly 10. The surface of the mounting device 50 is provided with at least two, and preferably three, additional pins 60, which are located in the inner row of holes 46 of the abrasive disc 38 and in the lower pad assembly. It is arranged so as to be aligned with the hole 16 of the solid body 11. Moreover, the pin 60 is long enough, i.e., of sufficient height, to fit into the hole 13 at the upper end of the upper pad portion 12, and since the hole 13 does not have a rear end, The abrasive disk 38 has its hole 4
6 and 48 are positioned to be aligned with the tips 30 of the outer row of holes 18 and the tips 34 of the inner row of holes 16, respectively.

The outer periphery of the mounting device 50 has an upright wall portion 62 . The outer surface of the upright wall 62 tapers inwardly as indicated at 64 and includes a lip 66 for retaining a resilient O-ring or the like. Hole 4 from Figure 3
6,56 over their respective pins 60,54, the abrasive disc 38 is first placed face down onto the floor or surface 52 of the mounting device 50, and then the pad assembly 10 is similarly placed. It will be appreciated that the pins 60, 54 are lowered. O-ring 68 can then be moved upwardly so that O-ring 68 automatically pulls flexible skirt 42 upwardly along the tapered sidewall of pad assembly 10 as shown in FIG. It is housed in the groove 44 as shown.

An alternative type is a nested attachment device, such as that shown in our Canadian Patent No. 772,369, granted November 28, 1967. Such a nested attachment device would of course have to use the pin assembly disclosed herein.

Now, referring to FIG. 4, the pad assembly 10
is shown during a surface polishing operation of workpiece 70. Because the upper pad portion 12 is constructed of a relatively stiff material, substantial pressure can be applied to the peripheral area of the pad assembly 10, and most rotary abrasions are applied to this peripheral area of the pad assembly. The flexible lower wall of the groove 20 ensures that the largest portion of the surface of the lower pad assembly 11 contacts the surface of the workpiece 70 because of the pressure applied thereto.

From FIG. 4, it can be seen that the abrasive sand 72 passes through the groove 20 and the outlet hole 2.
6 and into the vacuum housing H shown in dotted lines.

Referring to FIGS. 5 and 6, an additional flexible sponge pad 73 constructed of sponge or similar material is inserted between lower pad assembly 12b and abrasive disk 38.
As shown in FIG. 5, the sponge pad 73 has an inner row of holes and an outer row of holes that connect to the lower pad assembly 12.
It is provided to align with the hole b. Sponge pads 73 are typically used in cases where more flexible abrasiveness is required and the elasticity of the sponge pads provides greater "resilience" to the abrasive disc when the operator is, for example, grinding areas with different contours. used. In the past, the sponge pad 73 has often slipped off the lower pad assembly 12b after long periods of use. According to the embodiment of FIGS. 5 and 6, lower pad assembly 12b includes a plurality of small projections 74 on its bottom surface.
The small protrusion 74 is formed when the sponge pad 73 is placed opposite the lower pad assembly 12b.
Two surfaces of the member in question, namely 73 and 12b, are additionally grasped. Although the lower pad assembly 12b is shown in FIG. 5 as having only a small number of protrusions 74, these protrusions can be arranged in any desired density and are typically It will be appreciated that the side pad assembly 12b may be provided over the entire surface thereof.

The protrusions 74 are particularly embedded in the upper surface of the sponge pad 73 in the peripheral region facing the surface to be polished, i.e. in the juxtaposed surfaces, so that no actual clutching action occurs between the two gripped surfaces. be understood. Furthermore, it will be understood that even if the surface of the sponge pad 73 is slightly removed from the surface of the lower pad assembly 12b, the sponge pad 73 rests on the top of the protrusion 74 and will not slip due to rotation.

Although the invention has been described with reference to particular embodiments and particular applications, those skilled in the art will recognize that various modifications thereof can be made without departing from the spirit and scope of the invention as set forth in the claims. The terms and expressions used herein are used as descriptive terms and are not intended to be limiting and therefore exclude equivalent features or portions shown and described. It will be understood that no use of such terms and expressions is intended, and that various modifications may be made within the scope of the invention as claimed.

[Brief explanation of the drawing]

FIG. 1 is a partially cut-away top view showing some of the elements of the pad assembly in cross-section, and FIG. 2 is another view of the pad assembly showing several elements assembled. Partially missing top view, Figure 3 is the same as Figure 2.
4 is a cross-sectional view of a portion of the pad assembly in operation; FIG.
6 is a perspective view of yet another embodiment of the lower pad assembly, and FIG. 6 is a cross-sectional view similar to FIG. 3, illustrating the additional embodiment of FIG. 5. 10... Pad assembly, 11... Lower pad part, 12... Upper pad part, 12a... Upper disc, 12b... Lower disc, 14... Head member,
16... Inner row of holes, 18... Hole, 20... Groove, 22... Radial inner end, 24... Radial outer end, 26... Hole, 28... Sleeve, 30... ...Tip portion, 32...Rear end portion, 34...
... Tip part, 36 ... Rear end part, 38 ... Polishing disk,
40... Lining member, 42... Skirt, 44...
groove, 46... hole, 48... hole, 50... mounting device, 52... platform, 54... center pin, 56... center hole, 58... center hole, 60...
Pin, 62... Upright wall section, 66... Lip, 68
... O-ring, 70 ... Processed product, 72 ... Polishing sand, 73 ... Pad, 74 ... Protrusion.

Claims (1)

[Claims] 1. A pad assembly for a vacuum rotary sander, comprising:
The assembly includes: (a) a circular upper pad portion made of a stiff but resilient material; and a plurality of holes arranged at uniform intervals approximately halfway between the center of the upper pad portion and the outer periphery of this portion, and a corner located in the direction in which the pad assembly rotates from each of the holes. (b) the pad assembly is further configured to be relatively pliable and flexible; a lower pad portion made of a material having an inner row of holes and an outer row arranged so as to be uniformly spaced therein and coaxial with said portion; holes, the inner row of holes in the lower pad portion are aligned with the holes in the upper pad portion to form a plurality of inner vacuum holes, and the lower pad portion has the lower pad portion is adhered to the upper pad portion such that the outer row of holes in the upper pad portion are aligned with the outer ends of the grooves in the upper pad portion; (c) the material of the lower pad portion intermediate the inner row of holes and the outer row of holes forming the flexible bottom wall of the groove; (c) the upper pad portion; has an inwardly and upwardly tapered peripheral sidewall having a groove adjacent its upper end, and the pad assembly is adapted to receive an abrasive disc on its lower surface. , the abrasive disk is a flexible abrasive disk with holes in the disk aligned with holes in the lower pad portion and held in grooves in the side wall by a resilient retaining device. (d) said pad assembly is further adapted to be fixedly and rotationally fixed on said upper pad portion coaxially with said upper pad portion; a vacuum rotator having a circular rigid head member adapted to be coupled to a vacuum device, the head member having a plurality of holes slightly larger than the holes aligned with the holes in the upper pad portion; Sander pad assembly. 2. A pad assembly according to claim 1, wherein the upper pad portion is formed by two flexible disks, the upper disk having a uniform shape therein. the plurality of spaced-apart holes, and the lower disc is less rigid than the upper disc and has an angular outward shape within the lower disc. A padded assembly having an elongated groove extending into the pad. 3. The pad assembly according to claim 1, wherein the hole provided in the upper pad portion and the hole provided in the head member are slightly elongated in the direction of the elongated groove. Padded assembly. 4. The pad assembly according to claim 1, wherein both the inner row of holes and the outer row of holes provided in the lower pad portion are aligned with the direction in which the pad assembly rotates. elongated in opposite directions to form a front portion and a rear portion in each hole;
A pad assembly wherein the forward portion of the inner row of holes is aligned with the inner end of the holes in the upper pad portion and the rigid head member. 5. The pad assembly according to claim 1, wherein the lower pad portion has a plurality of protrusions on its lower surface, and the pad assembly comprises:
a secondary pad having a hole aligned with a hole in the lower pad portion, the secondary pad being disposed between the lower pad portion and the abrasive disk, and the protrusion A pad assembly adapted to be slidably and non-rotatably retained relative to the lower pad.