US2255571A

US2255571A - Means for isolating machinery

Info

Publication number: US2255571A
Application number: US304863A
Authority: US
Inventors: Rosenzweig Siegfried
Original assignee: Individual
Current assignee: Individual
Priority date: 1939-11-16
Filing date: 1939-11-16
Publication date: 1941-09-09
Anticipated expiration: 1958-09-09

Description

p 1941- s. ROSENZWEIG 2,255,571

MEANS FOR ISOLATING MACHINERY Filed Nov. 16, 1959 2 Sheets-Sheet l &

ep 9, 1941- s. ROSENZWEIG MEANS FOR ISOLATING MACHINERY Filed Nov 16, 1959 2 Sheets-Sheet 2 15'. ROs-e'nz wei g,

Wa /Ag drwmw' Patented Sept. 9, 1941 UNITED STATES PATENT OFFICE.

2,255,571 MEANS FOR ISOLATING MAC'HI NERY Siegfried Rosenzweig, Long Island City, N. Y.

Application November 16, 1939, Serial No. 304,863

2 Claims.

This invention relates to means for isolating operating machinery from a floor or sub-base, and has primarily in view the utilization of organic materials of any kind, such, for example, as cork, in a novel way, to obtain an isolating efliciency equal to that obtainable with steel springs but at considerably less cost.

While cork has heretofore been employed as an isolating medium, nevertheless it has been the general practice to use it in sheets or blocks disposed horizontally beneath the machine to be isolated, that is, to use the broad surfaces of a unit or units of relatively shallow depth as the load sustaining surfaces between the base of the machine and the sub-base or floor. In some cases, it has also been heretofore proposed to use cork disposed vertically at the sides, but in this situation, the cork, unlike cork at the bottom, sustains no load. In installations where cork is used between the bottom of the machine and the sub-base, it carries the entire load and therefore it often becomes compressed to such an extent after a comparatively short period of use, that it loses its isolating efficiency. While in a measure this may be overcome by correctly calculating the thickness of the cork sheet relative to the load and using metal plates, nevertheless such calculations show that it would be necessary to provide a body of cork of such depth and large area that it would be cumbersome and impractical as compared with the cost of metal springs. In other words, cork of sufficient area and thickness to be useful for maximum isolation efliciency would be excessively expensive.

According to the present invention, it is proposed to support or suspend the machinery foundation upon vertically arranged spaced sections or blocks of cork located beneath the ends or sides of the machine, omitting cork isolation at thebottom entirely. In other Words, it is proposed to suspend the machine base or its concrete foundation as the case may be from the top sides of cork blocks so that the lowest point of the base or foundation is located below the upper or top sides of the cork blocks and held spaced above the sub-base. The said blocks are of sufficient depth to obtain the correct amount of deflection to obtain isolating efficiency and of the proper width to obtain permissible and optimum unit loading. Thus, the present invention distinguishes from the practices heretofore outlined by loading the upper surfaces of cork blocks located beneath opposite sides or ends or both of the machine base, while omitting cork between the sub-base, so that the vertical depth of the cork assumes the entire load. For example, if in-agivenillustration, providing isolation only on two sides would require blocks twenty inches wide, the same result would be obtained by providing blocks only ten inches wide on all four sides. Ordinary cork one inch thick will compress about one-sixteenth of an inch when loaded correctly. Thus, since large foundations are rarely less than 2'6" to 3' in depth, it is possible according to the present invention to obtain a deflection in the cork of 2", and more without resortingto a cumbersome construction, and at the same time, obtain a high efliciency isolation. In addition to properly loading the cork and obtaining correct isolation, the vertically loaded cork blocks also provide side isolation in a single structure. That is to say, by omitting cork at the bottom of the installation and using it only at the sides, the latter'not only serves to prevent the transmission of vertical vibrations to the sub-base or floor, but also prevents the transmission of horizontal vibrations resulting from torque incident to the operation of rotating machines at varying speeds.

' A further object of the invention is to provide a novel arrangement of cork supports which will provide a much simpler and cheaper construction of foundation than is obtainable with springs, and which reduces the elevation of the machine above the floor or sub-base. For example, if a given installation required cork twentyinches thick to be placed between the bottom of the machine base or foundation and the sub-base, it is obvious that the machine would be raised considerably above the sub-base. However, with the present invention, cork blocks of the proper top area could be placed about the sides of the machine and the latter suspended therefrom so that the actual elevation of the machine would only be the depth of the air space between the machine base or foundation and the sub-base.

With the above and other objects .in view which will more readily appear as the nature of the invention is better understood, the same consists'in the novel construction, combination and arrangement of parts, hereinafter more fully described, illustrated and claimed.

, A preferred and practical embodiment. of the invention is shown in the accompanying drawings, in which:

Figure 1 is a vertical cross sectional view showthe bottom face of the foundation (or base) and i a mple embodiment of the invention.

after it has set, the nuts 9 may be manipulated to lift the entire foundation from the bottom of the pit and transfer the load thereof .to the upper sides of the cork blocks thereby compressing the same and providing a dead air space between the foundation and the floor of the pit. When the foundation l I has been' elevated sufliciently from the bottom of the pit, having due consideration for the weight of the machine to be supported on the foundation, the device is ready for operation. I

A further modification of the invention is shown in Fig. 7, from which it will be observed that the ends of the structural members l2 embedded in the concrete foundation do not project into the cork load sustaining blocks. According to this embodiment, the sub-base F is provided with a receptacle or pit P In practice the structural reinforcing members l2 for the foundation are first laid in the bottom of the pit. The cork load sustaining blocks A are then placed between the ends of the structural members l2 and the ends of the pit, and if desired the side walls of the pit may be lined with the relatively thin non-load sustaining cork sheets, according to the embodiment shown in Fig. 4. The top sides of the cork load sustaining blocks A may be provided with suitable bearing shims or load distributing members l3 for supporting the ends of the horizontally arranged beams or equivalent members I4. When the transverse reinforcing elements 12 are laid on the bottom of the pit they are fitted with the suspending bolts l whose upper ends are intended to project above the beams M to receive the base of the machine. However, before the machine is placed in position on the beams, the concrete foundation i6 is poured within the cork walls and about the structural reinforcing elements l2, the bottom of the foundation being formed directly on the bottom of the pit. After the concrete foundation has hardened, the machine base I! may be positioned on the beams l4 and over the upper threaded ends of the suspending bolts 15. The nuts l5 on the suspending bolts may then be manipulated so as to elevate the foundation I6 so that the bottom thereof becomes spaced from the bottom of the pit. Thus, the entire load of the foundation and the superimposed machine is transferred to the top sides of the blocks A which may be solid throughout their length and depth, in the sense that they are not pierced in any way by the structural elements in the foundation.

A further modification of the invention is shown in Fig. 8 which functions similarly to the construction shown in Fig. 7, the difference, however, being that the beams I4 of Fig. 7 are omitted and the machinery base itself becomes the means for transmitting the load of the foundation and the machine directly to the upper sides of the cork load sustaining blocks. Referring specifically to Fig. 8, it will be observed that the sub-base F is provided with a receptacle or pit P provided at its ends with the cork blocks A having at their top sides the bearing elements l8. The machine base [9 is substantially co-extensive in length with the pit so that the to raise the foundation from the bottom of the pit and transfer the entire weight of the foundation andmachine to thetop sides of the cork load. sustaining members As. As shown, the isolating mediumimay be cut away at the center if the entire width is not required from the standpoint of loading.

Figure 9' of the drawings illustrates a further modification of the invention embodying the same features and principles described in connection with the remaining figures of the drawings. In this figure, the hanger type machine supports perform thesame function as the pan or containerpreviously referred to. That is to say, the machine support includes members having a bottom portion 23 connected to an upwardly extending side member terminating in the outwardly projecting arm 24 which bears on the top sides of the cork blocks A. The machine M has its base resting on the bottoms 23 of the machine supports, and in this construction, as in the other embodiments, the lowermost point of the machine support is spaced above the sub-base or floor while the lowest point of the machine itself is located or disposed substantially below the top load sustaining sides of the cork blocks A From the foregoing, it will be apparent that in all forms of the invention, it is proposed to utilize cork load sustaining blocks so spaced and arranged as to carry the entire weight of a foundation and/or the machine itself on the top sides thereof. In all forms a receiving space is provided for the machine or its foundation or cork isolating means. Also, in every instance, the foundation or base of the machine is elevated or spaced from the bottom of the pit. This air chamber between the :bottom of the foundation and the bottom of the pit, may be made by utilizing means which initially provides, and subsequently maintains, the proper spacing between the bottom of the foundation and the bottom of the pit or other sub-base surface, or, on the other hand, the foundation may be poured directly on the bottom of the pit or other sub-base surface and. be subsequently lifted simultaneously with the loading or compressing of the cork blocks.

I claim:

1. Avibration isolating structure for operating machinery, comprising, in combination, a subbase including a horizontal surface, retaining walls perpendicular to said surface, isolation means in the form of slabs of resilient nonmetallic material of rectangular cross-section, said slabs having their lower ends resting on the said surface of the sub-base and their outer faces engaging said retaining walls and arranged to form an enclosure which provides an inner lining for the retaining walls, a machinery support fitting into the enclosure formed by said slabs and having continuous bottom and side walls, said side walls of the support engaging the inner faces of the said slabs to confine the same relative to the retaining walls and cause such slabs to absorb horizontal vibrations resulting from torque incident to the operation of machines rotating at high speeds, means carried by said support and resting on the upper ends of the said slabs to impart vertical vibrations thereto and cause the slabs to absorb and prevent transmission of vertical vibrations to. the subbase, and said means also mounting the support to suspend the bottom wall of the support above the horizontal surface of the sub-base to provide a trapped air pocket between the support and the- 7 closure formed by said slabs, a concrete foundation in the pan,.said pan having. continuous bot- 15 tom and side walls, said side walls engaging the inner faces of the slabs to absorb horizontal vi brations resulting from torque incident to the operation of machines'rotating at high speeds, flanges carried by the upperedges of the side wallsof the pan and resting on the upper ends of said cork slabs to impart vertical vibrations theretoxand cause the slabs to absorb and prevent the transmission of vertical vibrations to the sub-basesaid'fianges also supporting the pan on the-slabs to suspend the bottom wall of the pan above the horizontal surface of the sub-base to provide a trapped air pocket between the pan v and the horizontal surface of the sub-base.

7 I SIEGFRIED ROSENZWEIGJ