CA1148205A - Combination vibration damper and fastener for two panels - Google Patents

Abstract

ABSTRACT OF THE DISCLOSURE
A combination vibration absorbing damper and fastener for fast union of two panels comprises a part integrally formed of one pair of trunks incorporating snap fasteners, a head portion of the shape of a suction disc, and an axial connection member incorporating a damper and a part formed separately from the first part of a head portion of the shape of a suction disc and a damper piece. Fast union of two panels is accomplished by allowing the fitting holes bored in advance in the panels to be fitted around the opposite leading ends of the device complete with the part incorporat-ing the pair of trunks connected to the other part, and subsequently bringing the fasteners of the trunks into fast engagement with each other. The dampers consequently inter-posed between the opposed panels serve to absorb vibrations generated in one of the panels and prevent such vibrations from being transmitted to the other panel.

Description

8;~5 COMBINATION VIBRATION DAMPER AND FASTENER FOR TWO PANELS
This invention relates to a combination vibration damper and fastener for two panels, which comprises few component parts and can be attached to the panels with a simple operation.
There are times when two panels must be fastened at a fixed distance apart from each other so that mechanical vibrations generated in oné of the panels are not trans-mitted to the other panel. Such a situation occurs when a compressor is fastened to the bottom panel of the refriger-ator, for example, The conventional methods and dampers designed to meet the re~uirement, however, have necessitated use of many component parts and entailed very troublesome fastening work. In the case of a damper to be used in fastening a compressor to a refrigerator, for example, the work involves the steps of planting support pins in advance, by welding, to the bottom panel (as one of the two panels subjected to union), fitting rubber sleeves as the damper around the support pins, then, lowering the compressor toward the bottom panel thereby allowing the support pins to pass into corresponding perforations bored in advance in fitting ears (as the other panel) provided stationarily on the com-pressor, and fitting E-rings around the support pins thereby fastening the two panels or the compressor and the bottom panel in ~he present case. It is only natural that in most cases, union of two panels involves a plurality of fastening .,s ~
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2~5i points such as at the four corners in the boundary of the compressor, for example. Since the troublesome work mentioned above must be carried out at each of a plurality of fastening points, union of two panels by the conventional method has entailed much labor and inevitabl,y increased the prices of products.
Among the steps involved, there are included those which demand the attendance o~ skilled workers as in the step of welding. Even the attachment of E-rings turns out to be a more troublesome job than would ordinarily be expected. Thus, with the conventional method of fastening, the selection of skilled workers has been a critical factor.
In spite of such a troublesome work as described above, the conventional damper has had no alternative but to rely for its function solely upon the rubber sleeves, and it has ' ' suffered poor design freedom in the optimization of the degree of damping.
One object of this invention, therefore, is to provide a combination vibration damper and fastener which is formed of few component parts, permits anyone to bind two panels simply and quickly, and confers damping function upon the panels so fastened.

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Thus, the object of the invention is attained by a combination vibration damper and fastener for fast union of two panels each having a fitting hole which comprises a pair of snap fasteners and an axial connection member for connecting the snap fasteners back to back to each other with the snap fasteners each having a head portion, a trunk extended from the head portion and elastic engaging pieces provided on the trunk and adapted to snap into fast engagement with the fitting hole bored in the panel. The axial connection member has a pair of damper pieces extended radially between the opposed head portions of the paired fasteners and adapted to come into intimate, resilient contact with each other with one of damper pieces being connected to the head portion of one of the snap fasteners and independently separated from the other damper piece and from the other snap fastener so as to render the one of damper pieces slidably movable on the axial connection-member in its axial direction.
The other objects and characteristics of the present invention will become apparent from the further disclosure of the invention to be made hereinafter with reference to the accompanying drawings.

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z~s FIG. 1 is a schematic structural diagram of a conven-tional damper.
FIG. 2 is a sectional view of one embodiment of this invention illustrated in a disassembled form.
FIG. 3 is a side view of the embodiment of FIG. 2 taken in a direction rotated by 90 from the direction of FIG. 2.
FIG. 4 is a sectional view of the embodiment of FIG. 3 taken along the line I~-IV of the diagram of FIG. 3.
FIG. 5 is a half-sectioned side view of the same embodi-ment in a state of actual use.
FIG. 6 is a plan view.
FIG. 7 is a sectional view of the important part of the embodiment taken along the line VII-VII in the diagrams of FIG. 2 and FIG. 6.
A typical damper heretofore known to the art is constructed as illustrated in FIG. 1. In the attachment of a compressor to a refrigerator, for example, this damper necessitates work which involves the steps of planting support pins in advance, as by welding, to the bottom panel Pl of the refrigerator, itting rubber sleeves around the support pins, setting the fitting panel P2 f the compressor around the rubber sleeves now enclosing the support pins, and finally fitting E-rings R around the protruding ends of the support pins thereby fastening the two panels Pl, P2~ Although just one fitting point is illustrated in the diagram of F~G. 1, there are actually a plurality of fitting points. Thus, the Z~35 union of the two panels involves much labor as mentioned above. Moreover, each damper unit is formed of many compo-nent parts and is inevitably priced high.
The attachment of the compressor to the refrigerator described above is not the sole use found for the damper of the kind under discussion. It ~an be used in all applications in which sources of vibrations are attached to first panels Pl through the medium of second panels P2 such as in the form of fitting pieces. Such applications can be collectively represented in terms of the relation between the two panels, Pl and P2, described above. In the following illustration of the embodiments of this invention with reference to the accompanying drawings, therefore, the objects to be bound by the combination vibration damper and fastener will be in-variably represented as first and second panels, Pl and P2.
FIG. 2 is a sectional view of the first embodiment ofthis invention in a state ready for use or in a state freshly produced by injection molding of a plastic material, and FIG. 3 is a side view of the embodiment of FIG. 2 taken in a direction rotated by 90 from the direction of FIG. 2. As illustrated in these diagrams, the device 1 of this invention ;
fundamentally comprises two parts 2, 3. For the convenience of illustration, the device will be described first with reference to FIG. 5 which is a half-sectioned side view of the device in a state already assembled and put to use, as observed in the same direction as in FIG. 2. The device 1 is ~3L4~3Z~5 provided with a pair of snap fasteners 4, 5 axially opposed back to back to each other. By means of these fasteners 4~ 5, the device is snapped into engagement with the fitting holes Hl, H2 f the first and second panels Pl, P~. The device is also provided with a connection shaft 6 which fastens the pair of fasteners back to back as separated mutually by a fixed distance in the axial direction. Around this connection shaft 6 are disposed components which co-operate to produce a damping function.
Referring to FIG. 5, easier comprehension of the device of the present invention may be obtained by regarding this device as consisting of the portion under the imaginary line L which is the snap fastener 4 for engagement with the fitting hole Hl in the first panel Pl, the portion above the imaginary line L' which is the snap fastener 5 for engagement with the fitting hole H2 in the second panel P2, and the portion M
intervening between the two imaginary lines which is the axial connection member 6 and the damper function member to be described more fully below.
The structure of the snap fasteners 4, 5 can be one of the well-known structures in the art of plastic fasteners and rivets. Otherwise, it may be of the so-called canoe type, hook type, or any other type. In the present embodi-ment, the snap fasteners are represented as having an anchor type structure. Although the sizes of the two faste,ners 4, 5 can be freely selected to suit the sizes of the respective ~L4~ 35 fitting holes and the thickness of the panels, they can have identical structures to fulfill their functions effectively. So the fundamental components of the snap fastenei-s will be collectively described. First, they have fastener head portions 7, 8 designed for collision with the opposed surfaces of the panels Pl, P2. From the head portions 7, 8 axially extend respective shanks or trunks 9, 10. The trunks are provided with elastic engaging pieces which are flexible inwardly and outwardly in the radial direction. The elastic engaging pieces 11, 12 are provided at their free ends with engaging surfaces 13, 14 which come into engagement with the edges of the fitting holes Hl, H2 of the respective panels Pl, P2 on the sides opposite the head portions 7, 8. In the present èmbodiment, each fastener is provided with a pair o~ diametrically opposite elastic engaging pieces. Provision of just one elastic engaging piece may prove satisfactory when the force exerted thereby to fasten the panels Pl~ P2 is sufficient. Conversely, four such elastic engaging pieces may be circumferentially spaced at fixed angular intervals of 90. Thus, the number of elastic engaging pieces can be freely selected. The fastener 5 for engagement with the second panel P2 appears in the diagram to possess four elastic engaging pieces, because there are a pair of elastic arms 15 which are disposed per-pendicularly to the genuine elastic engaying pieces ,12. Asone additional desirable measure contemplated in the present ~82~5 embodiment, these elastic arms 15 function to check the upward movement of the panel as described more fully below.
They have no direct bearing upon the fastening of the panel P2 . .
The fastener head portions 7, 8 are formed in the shape of suction discs. Optionally, they may be formed with flat tops. Of course, the fasteniny of two panels Pl, P2 by means of the fasteners o~ the known structure mentioned above is effected by the work generally performed with other fasteners of this kind. This work will be described briefly.
First, the trunk 9 of the first fastener 4 is inserted in the direction of the .leading end thereof into the fitting hole Hl of the first panel Pl. In consequence of this in-sertion, the elastic engaging pieces 11 which in the normal state protrude past the edge of the fitting hole collide with the edge of the hole and then slide past the edge while being gradually bent inwardly. When the engaging su~faces 13 at the free ends of the elastic engaging pieces ride over the edge of the hole, the elastic engaging pieces which have been contracted resume their original shapes and bring the engaging sur~aces into fast engagement with the edge of the hole.
Consequently, the panel Pl is nipped between the engaging surfaces 13 and the head portions 7. In other words, the device 1 is planted in the panel Pl.
Then, the second panel P2 is inserted through the medium of the fitting hole H2 thereof into the second fastener 5 z~s which is disposed upwardly. Consequently, the elastic engaging pieces 12 of the second fastener 5 are bent in-wardly by the edge of the fitting hole in this panel. When the panel P2 is pushed down until it collides with the head portion ~, the relationship of the contact in the radial direction between the engaging pi.eces 12 and the edge of the hole is dissolved and the engaging pieces 12 resume their original shapes by virtue o~ the force of elastic recovery built up in themselves, with the result that the engaging surfaces are brought into fast engagement with the edge of the hole on the side opposite the head portion 8. This completes the fastening of the second panel P2. As a result, the panel P2 is held fast to the panel P1 separated by a distance commensurate with the axial length of the connection member 6 serving to connect the two fasteners in the axial direction.
The vibration damper function of the device, which is utilized to prevent the vibration of the second panel P2 from being transmitted to the first panel Pl, is as a rule ful-filled by a pair of damper pieces 16, 17 disposed around the axial connection member 6 and radially extended until their boundaries come into mutually resilient contact. In the present embodiment, the two damper pieces 16, 17 are formed in the shape of suction discs opposed to each other.
One of the two damper pieces 16, 17, which in the illustrated embodiment is the damper piece 16 on the fastener s 4 for engagement with the first panel Pl, is molded integ-rally with the axial connection member 6. The other damper piece 17 is integrally molded with the head portion 8 of the fastener 5. This damper piece 17 and the head portion 8 form one independent part 3 which is separated from the axial connection member 6. The cent~al perforation 18 of the part

3 is idly set around the axial connection member 6.
The fundamental construction of this invention has been described. When vibrations occur in the panel P2 which is fastened to a source of vibration such as a compressor, these vibrations are transmitted via the fastener head portion 8 separated from the other parts an~ pressed against the lower surface of the panel P2 to the damper piece 17 integral with the fastener head portion 8. On reaching this damper piece 17, the vibrations are absorbed by virtue of the resilient contact the damper piece 17 maintains with the other damper piece 16.
By the device 1 of this invention, the fastening of the two panels Pl, P2 can be accomplished b~ the sole operation of insertion of the fasteners 4, 5 toward each other as described above. At the same time that this simple work of fastening is completed, the damper pieces 16, 17 cooperate to absorb vibration. Moreover, the capacity for damping can be adjusted substantially infinitely by suitably fixing the radial extension of the pair of damper pieces, selecting the material for the damper pieces, and when the damper pieces ~82~S
are formed in the shape of suction discs, determining the conditions of their recesses. Thus, optimal damping capacity can be o~tained to suit the purpose of use. In fact, the device of this invention designed and fabricated specifically for use in the attachment of a compressor to a refrigerator has been demonstrated to transmit substantially no vibration to the bottom panel of the refrigerator (P1).
Since this device is fundamentally composed of two parts, it is necessary that the second part 2, namely, the part 3 which comprises one fastener head portion 8 and one damper piece 17, should be attached fast to the first part 2 before the second panel P2 is brought into fast engagement As is clear from FIG. 2 and FIG. 3, this can be done with simplicity. To be specific, it is effected by forcing the part 3 downwardly in the axial direction thereby allowing the leading end 21 of the trunk 10 of the fastener S having a separate head portion 8 to be axially inserted into the central perforation 18 of the part 3, then causing the part 3 to slide over the elastic engaging pieces 12 while inwardly bending the elastic engaging pieces 12, and bringing the part 3 into contact with the other damper piece 16 and, at the same time, to snap into fast engagement.
Now, measures whose incorporation into ~he aforementioned fundamental construction proves desirable for the purpose of this invention will be described.
Once the second part 3 has been snapped into position, 32~5 it is desired not to produce any play in the horizontal direction around the axial connection member 6. This is important for the purpose of safely maintaining the two damper pieces 16, 17 in tight mutual contact. Due attention to the relation between the radius of the axial connection member 6 and that of the central perforation 18 of the part 3 ought to suffice for preclusion of such undesirable play of the part 3. For example, one efecti~e measure may be providing the elastic engaging arm 12 of the fastener 5 with guide pieces 19 adapted to plerce axially into the central perforation 18 and, in case where there are provided elastic arms 15 for stopper function to be described more fully below as in the present embodiment, similarly providing such elastic arms 15 with similar guide pieces 20, so that the outer surfaces of these guide pieces 19, 20 will press the inner wall surface of the perforation. By this static measure, the individual guide pieces 19, 20 even while in a kinetic state discharge the role of axial guides capable of restricting vibration of the part 3 due to vibration of the panel P2 to only the axial direction.
The pair of elastic engaging arms 15 possess a stopper - function serving to restrict by virtue of their inherent elasticity the distance of movement of the panel P2 in the upward direction in consequence of exposure to vibrations.
The reason is as follows. The panel P2 is nipped between the head portion 8 of the fasttner 5 for engagement with the other 8;~5 panel and the engaging surfaces of the elastic engaging pieces 12. When it tends to move in the upward direction on exposure to vibration, it applies the pressure due to the movement exclusively to the elastic engaging pieces 12 via the engaging surfaces 14. If the distance of this upward movement is not restricted, there is a possibility that the panel P2, when caused to rise high, will possibly inflict serious damage to the engaging pieces 12. Even if no damage is inflicted to the engaging pieces 12 r there is still a possibility that the panel P2 which has risen high and fallen again will exert a serious, pulsive impact of a low basic frequency upon the damper pieces 16, 17 and, as the result, the damper pieces will be unable to absorb this impact but will allow the impact to be transmitted to the first panel Pl.
To cope with this situation, therefore, the pair of stopper elastic arms 15 are provided at the lower ends thereof with stopper surfaces 22 separated by a distance indicated by "t" in the diagrams of FIG. 3 and FIG. 5 ~rom the upper surface of the~panel P2 or from the engagi~g sur-faces 14 of the pair of engaging pieces 120 If the panel P2 is vibrated upwardly by any chance, it is allowed to jump up until it collides with the stopper surfaces 22 and no more.
The reason for entrustment of the stopper function to the arms 15 possessing elasticity is that, when the part, 3 is brought into position, the insertion of this part 3 is not s hindered because the arms 15 can be bent inwardly as already described above.
Further in the present embodiment, the elastic engaging pieces 12 which primarily ulfill engaging function alone are adapted to perform concurrently stopper function and vibration absorbing function. To be specific, the base portions 23 which serve as the fulcrums to permit the elastic engaging pieces' bending are not directly formed on the wall surface of t~he trunk as are generally found in fasteners of this kind but are formed to continue into the reinforcing crosspieces 25 formed axially within the empty space through the medium of the arms 24 which are bent inwardly substantially at a right angle in the radial direction. As a result, the whole amount of the bending in the vertical direction can be in-creased enough to permit ample absorption of the uppercomponent of vibration. In addition, the trunk 10 is provided at the leading end thereof with brims 26 a prescribed distance above the arms 24. When the panel P2 is thrown up high by a vibration and the engaging pieces 12 are wholly bent upwardly by the aforementioned prescxibed distance, part of the arms 23 collide with the lower surface of the brims 26. Beyond that point, the engaging pieces 12 are not allowed to be bent any further.
Moreover, the device is wholly molded of a plastic material. When the panel P2 happens to be made of a metal and it is vertically vibrated with a clattex within a horizon-32~3~
tal plane, there is a possibility that the edge of the fit-ting hole H2 will scrape the outer surfaces of the various parts of the device positioned inside the fitting hole. In the present embodiment, therefore, along the inner wall surface of the central perforation 18 of the part 3 consisting o the Eastener head portion 8 and the damper piece 17, the guide pieces 27 peripherally located in the four empty spaces formed by the elastic engaging pieces 12 and the stopper arms 15 of the second fastener S are adapted to rise axially beyond the head portion 8, so that the outer surfaces of the guide pieces 27 check the motion of the panel P2 due to the play of the inner wall surface of the fitting hole Hl.
The head portions 7, 8 of the fasteners 4, 5 are formed in the shape of suction discs as previously described. This particular shape proves desirable in respect that it gives more allowance for the variations in the thicknesses of the panels Pl, P2 and, at the same time, confers a vibration absorbing function, if to a limited extent, upon the head portions 7, 8.
Further in this embodiment, the axial connection member 6 is provided concentrically above the underlying suction-disc-like damper piece with an auxiliary elastic piece 28 similarly formed in the shape of a suction disc. The peri-phery of this auxiliary elastic piece 28 is opposed across a distance to the lower surface of the radially inner!portion of the upper damper piece. This auxiliary elastic piece 28 82~i produces absolutely no effect so far as the weight of the source of vibration such as a compressor on the panel P2 is within the limits of the standard design level. When considerably lar~er weight bears on the device 1, however, the pair of damper pieces 16, 17 are heavily deformed possibly to a point where the suction discs of the damper pieces tend to be crushed flat. In such a case, the leading end (periphery) of this auxiliary elastic piece 28 colloides with the lower surface of the upper damper piece and keeps it from falling further. It serves to enhance the static -strength of the pair of dampers 16, 17 and help them to with-stand large gravity. When a passing dynamic impact is in-flicted upon the device, this auxiliary elastic piece 2~
discharges its part of restricting the distance of downward movement of the part 3 as a whole and enabling the lower damper piece 16 to retain its elasticity suitably. Thus, the device amply withstands and absorbs the dynamic impact.
The damper pieces 16, 17 are not necessarily limited to the shape of suction discs but may be formed in any other shape on condition that they will fulfill the function described above. For example, they may be circumferentially divided into several parts. ~therwise, one of the pair of damper pieces may be in the shape of a flat disc and the other damper piece in the shape of the curved surface of a cone with the periphery extending toward the flat disc.
Where the auxiliary piece 28 is incorporated, the same rule ~8~S
applies thereto. Optionally, one pair of such auxiliary pieces may be symmetrically disposed in the axial direction.
As described above, this device 1 is a combination of the two parts 2, 3. As occasion demands, the two parts 2, 3 may be molded as completely independent pieces from each other as indicated by the solid lines in FIG. 2 and FIG. 3.
What is indispensable to the effective operation of this device is that after the two parts 2, 3 have been assembled, at least one of the two damper pieces should, in conjunction with the fastener head portion of the part including that ... .
damper piece, be allowed to produce a sliding motion freely relative to the other part 2. (In other words, the parts 2, 3 should be retained as independent pieces from each other even after their assemblage.) At the time that these two lS parts 2, 3 are produced by injection molding a plastic ma-terial, therefore, it is more desirable to have them integrally molded than otherwise, because the integral molding permits a saving in the number of expensive metal dies required for the molding.
In the case of this invention, therefore, the two parts 2, 3 are integrally molded in a manner such that the lower edges of the inner wall surfaces of the guide pieces 27 in the part 3 are radially connected through the medium of brittle portions 29 to the outer peripheral surfaces at the leading ends 21 of the trunks 10 of the upper fastener in the part 2 as illustrated in FIG. 7. At the time that the two parts are - 17 ~

assembled into an operative position by lowering the part 3 into position, a powerful blow is delivered to the part 3 so as to tear the brittle portions 29. FIG. 7 represents a sectional view of the important part of the device taken along the line VII-VII of the diagram of FIG. 2 and the line VII-VII of the diagram of FIG. 6 (a top view). Further in FIG. 2, the part 3 which is in a state connected through the medium of the brittle portions to the other part is indicated by the imaginary line. Besides the aforementioned saving in the number of expensive metal dies, such integral molding of the two parts 2, 3 offers an advantage that less time and labor is required in transporting the parts 2, 3 when formed integrally and that the possibility of the parts being lost in transit will be reduced.
This invention enables a combination vibration absorbing damper and fastener for two panels to be produced by simple assemblage of only two parts as described in detail above.
Moreover, attachment of this device to the panels is accom-plished by a very simple work of pushing. It can be worked by anyone, skilled or unskilled. When the fastening of two panels involves many fastening points, the total time re~uired for the work is negligibly small. This invention promises appreciable reduction in the product cost.

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Claims (14)

The embodiments of the invention in which an exclusive property or privilege is claimed are defined as follows:

1. A combination vibration damper and fastener for fast union of two panels each having a fitting hole, com-prising a pair of snap fasteners and an axial connection member for connecting the snap fasteners back to back to each other, the snap fasteners each having a head portion, a trunk extended from the head portion and elastic engaging pieces provided on the trunk and adapted to snap into fast engagement with the fitting hole bored in the panel, the axial connection member having a pair of damper pieces extended radially between the opposed head portions of the paired fasteners and adapted to come into intimate, resilient contact with each other, one of damper pieces being connected to the head portion of one of the snap fasteners and inde-pendently separated from the other damper piece and the other snap fastener so as to render the one of damper pieces to be slidably movable on the axial connection member in its axial direction.

2. The combination damper and fastener according to claim 1, wherein the elastic engaging pieces provided on one of the two trunks are provided at circumferentially adjacent positions with elastic arms adapted to perform a function of stopping the upward movement of the panels.

3. The combination damper and fastener according to claim 1, wherein the damper integrally formed on the trunks is provided with an auxiliary elastic piece on the side opposite the other damper.

4. The combination damper and fastener according to claim 2, wherein the damper integrally formed on the trunks is provided with an auxiliary elastic piece on the side opposite the other damper.

5. The combination damper and fastener according to claim 1, wherein a guide piece is disposed as extended upwardly on the inner wall surface of the part disposed separately of the trunks.

6. The combination damper and fastener according to claim 2, wherein a guide piece is disposed as extended upwardly on the inner wall surface of the part disposed separately of the trunks.

7. The combination damper and fastener according to claim 3, wherein a guide piece is disposed as extended upwardly on the inner wall surface of the part disposed separately of the trunks.

8. The combination damper and fastener according to claim 4, wherein a guide piece is disposed as extended upwardly on the inner wall surface of the part disposed separately of the trunks.

9. The combination damper and fastener according to claim 1, claim 2 or claim 3, wherein brims are integrally provided on one trunk as separated by a stated distance from the leading end thereof.

10. The combination damper and fastener according to claim 4, claim 5 or claim 6, wherein brims are integrally provided on one trunk as separated by a stated distance from the leading end thereof.

11. The combination damper and fastener according to claim 7 or claim 8, wherein brims are integrally provided on one trunk as separated by a stated distance from the leading end thereof.

12. The combination damper and fastener according to claim 1, claim 2 or claim 3, wherein brittle portions of a small wall thickness are formed to connect one portion of one trunk to one portion of the separate part so that the two parts may be integrally molded.

13. The combination damper and fastener according to claim 4, claim 5 or claim 6, wherein brittle portions of a small wall thickness are formed to connect one portion of one trunk to one portion of the separate part so that the two parts may be integrally molded.

14. The combination damper and fastener according to claim 7 or claim 8, wherein brittle portions of a small wall thickness are formed to connect one portion of one trunk to one portion of the separate part so that the two parts may be integrally molded.