US 2303393 A
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Description (OCR text may contain errors)
Dec. 1, 1942. E. SCHMIDT VACUUM LIFTING DEVICE Filed Jan. 10, 1940 2 Sheets-Sheet l Dec. 1, 1942. E. SCHMIDT VACUUM LIFTING DEVICE Filed Jan. 10, 1940 *2 Sheets-Sheet 2 F772 dezZ: 51 6723 Patented Dec. 1, 1942 UNITED STATES VACUUM LIFTING DEVICE Eugene Schmidt, Oak Park, Ill., assignor to Charles 0. Moore Application January 10, 1940, Serial No. 313,265
This invention relates to lifting and supporting devices and is concerned more particularly with such devices embodying safety releasable vacuum cups.
It is an object of my invention to provide a vacuum type load-supporting or' lifting device adapted to be held by hand and to suspend relatively heavy weights of metal sheet or other material and yet capable of being conveniently released by the hand holding the same without necessitating release of the hand from the device.
It is another object to provide a vacuum lifter of such character that the full pressure of the person's arm may be readily and conveniently applied to force the air from the lifter as the lifter is applied to a load.
A further object is to provide a vacuum lifter with a release which is so arranged that it'cannot be operated by accident.
Another object is to provide a device of this type employing a plurality of vacuum cups.
Additional objects are to provide a vacuum lifter valve and release assembly which is speedy and. positive in operation, involves a minimum of parts, all of which are readily assembled and accessible, and which will last indefinitely.
Further objects and advantages of the inventaken as Fig. 4 is a plan sectional view taken as indi- I cated by the line 4-4 in Fig. 3.
Fig. 5 is a plan view showing how a large sheet of metal or other material may be conveniently carried by several persons, each using one of my lifting devices near an edge of the sheet.
Fig. 6 shows how easily the cup is progressively flattened to provide suction.
Fig. 7 is an elevation of a tandem unit lifting device embodying features of the invention.
Figs. 8 and 9 are sectional views taken as indicated by the lines 8-8 and 9-9 respectively in Fig. 7.
Fig; l0 shows how the tandem device may be usedon a piece of work.
Fig. 11 shows another form of valve release.
sleevelike member l lhaving a bottom opening l5 substantially registering with and forming a continuation of the hole H. The sleeve has a threaded portion [1 projecting freely above the top [8 of the hub.
A preferably metallic or other handle 20, preferably cast or otherwise formed, maybe U-shaped and arranged to lie substantially in a plane of the axis of the cup Ill, with the arms 2! and 22 of the handle. extending transverse to said axis, so that when the axis is vertical the arms of the handle are generally horizontal. The lower arm 2| of the handle rests on the hub top l8 and has an opening 23 whereby it is readily slipped over the threaded sleeve portion ii. A nut 25 applied to the threaded portion I l engages the upper side 26 of the arm 2 l, thereby firmly clamping and securing the handle to the hub l2. A look or other washer may be added as shown.
The nut 25 is preferably in the form of a cup and has an air bleed hole 21 and anotherhole -28 through which a valve stem 29 extends and providing a bearing for the stem, the lower end 30 of the stem being molded or otherwise preferably integrally united to a resilient head 32 of rubber or other suitable material which serves as a Valve head in cooperation with the valve seat. 33 afforded by the sleeve I4 at [its opening .15. The bleed hole 2'! could of course be formed elsewhere. Aspring 34 coiled about the stem 29 and between the nut 25 and the valve head 32 yieldably closes the valve, generally indicated at35. H I
The stem 29 extends outside'of the nut 25 and has, a hook 35 between which and the nut25 a releaselever 3T, pivoted as at 38 to the arm 2|, extends, the spring 34 acting through said hook to yieldably retain the release element in 'depressed position as shown in full lines in Figs. 1 and 2. The hook arrangement makes possible relative movement of the stem andlever as the latter swings, and is illustrated for exemplary The terms top, bottom, upper, lower, purposes only, since the stem and release element may be assembled in any other suitable fashion to attain the desired end, or the release may be effected through the stem alone as in Fig. 11.
The upper arm 22 of the handle is adapted to be grasped by a hand of the operator as indicated in Fig. 1. The lever 31 is accordingly provided with a finger pull which may be in the form of a loop or hook 4| normally disposed adjacent the place of repose of one of the fingers, the index finger 42, for example, when a weight is being lifted by the device, so that, in order to actuate the lever, it is necessary merely to lower the end of the index finger and slip it laterally in under the hook 4| or forwardly through the space 44 to a position under the hook 4|, and, pull up on the latter'with a slight'force sufiicient to overcome the pressure of the spring 34 and thereby open the valve. This requires no change Whatever in the position of any other part of the hand, yet the hook 4| is; not in a position to be accidentally operated while thedevice is in lifting service. The bleed hole 21 in the nut 25 enables the air to enter the cup I0 very rapidly, so that the vacuum in the cup is broken practically instantly.
The lever 31 is preferably disposed substantially entirely within the confines of the handle 20, so that accidental actuation of the lever, as by striking against any object or inadvertent movement of'the thumb, which is likely to extend free of the handle since it does not exert a lifting effort, is precluded.
The device may be used in any capacity to which it is suited, a common use being the lifting of sheet metal, glass and other material for shifting the same from place to place without applying the hand directly to the object lifted.
The handle arms are so dimensioned and ar-' ranged relative to the cup that pressure is readily applied by the hand to progressively and completely flatten the cup from one portion of the rim 46 to the diametrically opposite portion of said rim, as shown in Fig. 6.
The principle of the form heretofore described may be utilized in a unit having a plurality of vacuum cups, such as the tandem unit-shown in Figs. '7 to 10, wherein the parts corresponding to those illustrated in Figs. 1 to 6 are designated ina most cases by the same numbers followed by the letter a. In this'arrang'ement the cups [0a are joined or bridged by a handle 26a, and-has a pair of levers 31a pivotedto the handle as at38a.
These levers may extend alongside each other mediate their ends by a pin-and-slot connection- 50, orequivalentmeans, comprising slots 5| in the levers and a connecting pin or rivet '52, the levers being preferably spaced apart 'by a washer 54.
With this construction it is evident that if either lever 31a is raised, the connection 'between the levers will cause the other lever 31a also to be raised, the'reby'opening both valves 35a simultaneously. Thus both cups may be pressed fiat at the same time or separately, as desired, to secure them in the desired positions on the work, and may be released at the sametime. This multiple type is desirable particularly in cases where a piece of considerable area is to be lifted by one-person, since by having a 'pliiralityjof points of support the article'wilfn'ot'be iinwleldly or unbalanceda disadvantage which would in many cases obtain when only one cup is used. The two hooks 4|a are provided so that the handle may be readily grasped in either hand with either cup adjacent the thumb portion of the hand, and, in any event, one of the hooks will be in cooperative relation to the index finger of the hand used.
Of course, the tandem form shown is merely illustrative, since a greater number of cups could be employed without departing from the principles of the invention.
The handle 20a may terminate substantially at the places of securement thereof by the nuts 25a, and may be formed of cast metal or other suitable material. A handle substantially in the form of an-endless loop is desirable because of rigidity. The grip 56 of the handle may be convex on its lower side as shown at 51 to keep the hand from slipping along the handle, so that the load'will be substantially evenly distributed at all times among the cups and the pull will be in the proper direction to enable each cup to operate with greatest efiiciency. Here, also,'the
release members 31a are shielded by the handle.
Another form of the invention is shown in Fig. ll, wherein the lever for releasing the valve is dispensed with, the releasing force being applied directly to the valve stem 29b. This stem could be formed with a pull or other finger operated portion to be'actuated by any desired digit, but,
for the reason given above, its finger pull '4Ib is disposed for actuation by the index finger of the hand applied to the handle 201). An' extension 58 on the stem is provided to have sliding movement in a bearing or guide 59 provided on the handle, the extension being at all times disposed in the guide when the parts are operatively assembled, without interfering with the closing of the valve. This arrangement insures reciprocatory movement of the stem sothat'it will not bind or bite in the nut 251). Here, as in the case with the other forms, the release member including the pull Mb is shielded by the handle against accidental operation, clearance 44b being affordedif desired," for the purpose described.
The parts other than the cups and valve heads are preferably made of metal, although'any other suitable materials may be used.
Any of the devices may be equipped with any 'of the handles or other'appropriate parts'of the other devices disclosed.
Various modifications may suggest themselves to those skilled -in"the-a'rt without departing from the spiirt of my invention, andQhence, vI do not wish to be restricted to the specific forms shown or usesmentioned, except to'the extent indicated in the appended claims,-which are to be interpreted as'broadly as the'state' of the art will permit. I
1. A resilient suction cup, andarelatively rigid handle therefona said handle-comprising connected lower and upper arms, means connecting said lower arm to said' cup, said upper arm extending overand havingafree-end and entirely spaced from said lower arm'a distance allowing ample clearance for the insertion of the fingers of the operators hand.
2. A resilient suction cup, and a relatively rigid handle therefor, said handle, comprising ,connected lower and upper arms, means inclu'ding a valve for said cup and connecting said lower arm to'said cup,"said upper arm extending'o'ver' and entirely spaced from said lower arm a distance allowing ample clearance for the insertion of the fingers of the operators hand.
3. A suction cup having a bleed hole and a recess thereabove, a sleeve molded in said recess and having a threaded extension above said recess, a handle over said cup and about said sleeve, a nut threaded on said sleeve and securing the handle to the cup, means establishing communication between the interior of the sleeve and the atmosphere, a check valve element in said sleeve between said bleed hole and said means and normally closing said bleed hole, and means operatively connected to said check valve element and operative by a hand grasping said handle for re leasing said valve element.
4. A suction lifting device comprising a vacuum cup provided with a valve including a substantially closed valve casing and a spring pressed reciprocable valve member in said casing and normally closing said valve, said member having an extension passing out of said casing, a handle supported by said cup, a valve-opening lever, and connections between said lever and said member and handle, one of said connections afiording lost motion between the connected parts.
5. A suction lifting device comprising a vacuum cup having a hub, means cooperating with said hub in providing a valve casing, a spring pressed movable valve-opening and -closing member normally seated in said casing, a lever pivotally supported relative to said cup and connected to said member, said lever having an actuating portion beyond said member, and a handle supported by said cup and arranged so that when said handle is normally held in a hand, said portion is in position to be actuated by a finger of the hand without inconvenience to the remainder of the hand.
6. A suction lifting device comprising a vacuum cup having a hub, means cooperating with said hub in providing a valve casing, a spring-pressed movable valve-opening and -closing member normally seated in said casing, a lever pivotally supported relative to said cup and connected to said member, said lever having an actuating portion beyond said member, and a handle supported by said cup and arranged so that when said handle is normally held in a hand, said portion is in position to be actuated by a finger of the hand without inconvenience to the remainder of the hand, said portion being substantially nested by said handle.
7. A lifting device comprising a pair of vacuum cups having valves, a handle bridging said cups, and means operable by a hand on said handle for simultaneously opening saidvalves, said means being disposed to be operated by a finger of the hand without requiring substantial relaxation of the grip.
8. A lifting device comprising a pair of vacuum cups having valves, a handle bridging said cups, and means operable by a hand on said handle for simultaneously opening said valves,
said means including operatively interconnected actuating members severally connected to said valves.
9. A lifting device comprising a pair of vacuum cups having valves, a handle bridging said cups, and means operable by a hand on said handle for simultaneously opening said valves, said means including operatively interconnected actuating members severally connected to said valves, said members having portions each arranged to be pulled by the index finger of the hand on the handle irrespective of the side of the handle at which the thumb is disposed.
10. A lifting device comprising a vacuum cap having a valve and a handle with a grip arranged to position an index finger laterally of said valve, said valve including a casing and a reciprocable valve member, said member having an extension outside of said casing, said extension projecting laterally of said valve and having a finger pull portion in proximity to and operable by the index finger when the hand is in place about the grip, and means facilitating movement of said member.
11. A suction lifting device comprising a vacuum cup provided with a valve including a substantially closed valve casing and a spring pressed reciprocable valve member, said valve member having an extension passing out of said casing, a handle supported by said cup, valve-opening means, and connections between said means and said valve member and handle, one of said connections affording lost motion between the connected parts.
12. A lifting device comprising a vacuum cup having a valve and a handle including a hand grip, and means arranged to be pulled by the index finger of a hand on said grip for releasing said valve, said means being disposed to be pulled to open said valve by the front of said finger when said finger is free of said grip, said means being shielded by said handle from accidental actuation by the thumb of said hand.
13. A lifting device comprising a pair of vacuum cups having valves, a handle bridging said cups, and means for simultaneously opening said valves, said means being disposed to be operable only pursuant to movement of a part of a hand on said handle to an abnormal position Without requiring substantial relaxation of the hand grip on said handle.
14. A lifting device comprising a pair of vacuum cups having valves, a handle bridging said cups, and means operable by a hand upon said handle for opening said valves,said means including operatively interconnected actuating members severally connected to said valves, said members having portions each operative selectively to simultaneously open said valves and arranged to be moved by a part of the hand on the handle without substantial relinquishment of the hand grip irrespective of the side of the handle at which the thumb is disposed.