US3851907A

US3851907A - Telescopic counterbalance

Info

Publication number: US3851907A
Application number: US00354702A
Authority: US
Inventors: B Sandor
Original assignee: Motors Liquidation Co
Current assignee: Motors Liquidation Co
Priority date: 1973-04-26
Filing date: 1973-04-26
Publication date: 1974-12-03
Anticipated expiration: 1991-12-03
Also published as: CA981708A

Abstract

A telescopic counterbalance for a hinged closure includes inner and outer telescopically related members. An internal compression spring biases the members apart to their telescopic outward position. The members are located in this position by the engagement of a collapsed rib located intermediate of the outer member with a plurality of spaced depressions located intermediate of the inner member. The members are releasably retained in this position by a spring clip on the outer member cooperating with the collapsed rib. The inner flared end of the inner member engages intermediately of the outer member and a plastic bushing on the inner end of the outer member engages intermediately of the inner member for improved bending strength. A wooden dowel mounted internally of the outer member extends through the compression spring and supports a compression spring on the free end thereof. This is engaged by a spring seat on the inner member during the terminal inward movement of the inner member to provide a pop-open force or additional opening force upon initial telescopic outward movement of the members.

Description

United States Patent Sandor Dec. 3, 1974 i 1 TELESCOPIC COUNTERBALANCE cludes inner and outer telescopically related members.

[75] Inventor Bela Sandor, D ctr Oit Mich. An internal compression spring biases the members apart to their telescopic outward position. The meml Assignee: General Motors Corporation, bers are located in this position by the engagement of Detroit, Mich. a collapsed rib located intermediate of the outer mem- (221 Filed: Apr. 26 1973 her with a plurality of spaced depressions located intermediate of the inner member. The members are rel l pp 354,702 leasably retained in this position by a spring clip on the outer member cooperating with the collapsed rib.

52 US. Cl. 292/262, 292/338 The imler flared end of the inner member engages 151 Int. Cl. E05c 17/30 F l of the outer member and a Plastic [58] Field of Search 292/262, 338; 16/49, 84, mg F the Outer member engages 16/85, 72, 197; 248/354, 402, 403; 49/379 termedrately of the inner member for improved bendmg strength. A wooden dowel mounted internally of [56] References Cited the outerdmember extends through the comprrlesi ion spring an supports a compresslon sprm on t e ree UNITED STATES PATENTS end thereof. This is engaged by a spring seat on the 2.071660 2/1937 SCl'lUlZ CI 8i. X inner member during the terminal inward mo ement 11332 g 292/338 of the inner member to provide a pop-open force or 5:714:67; 2/1973 s h l id iiiiiI::::::::.::::::::i:i:: 16/85 x additional Opening force upon initial telescopic Primary E.raminerRichard E. Moore Attorney, Agent, or Firml-lerbert Furman [57] ABSTRACT A telescopic counterbalance for a hinged closure inward movement of the members.

8 Claims, 8 Drawing Figures PATENTEE DEC 3 SIEEY 10F 2 TELESCOPIC COUNTERBALANCE This invention relates generally to telescopic counter-balances and more particularly to a telescopic counterbalance including a pop-open force which aids the counterbalance force in initially moving the telescopic members of the counterbalance toward extended position.

Telescopic type counterbalances are known. Generally, such counterbalances include inner and outer telescopically related tubular members which are biased outwardly of each other or toward extended position by an internal compression spring seating on respective spring seats internally of the outer ends of the members. The outer ends of the members are respectively pivotally connected to a closure and to the closure support to bias the closure to its open position and also to counterbalance the closure as it moves between open and closed positions. A stop on the inner end of the inner member is engageable with a stop adjacent the outer end of the outer member to locate the members in their extended position.

The counterbalance of this invention is of the telescopic type. but differs from known counterbalances in additionally including several features. One feature is that a booster compression spring is mounted on one of the telescopic members and is engaged and compressed by an abutment on the other member during the terminal inward movement of the members to store energy and provide an initial pop-open force aiding the main compression spring in initially biasing the members outwardly of each other and consequently initially biasing the counterbalanced closure toward a partially open position. Another feature is that the booster compression spring is mounted on the outer member internally of the main compression spring and is located adjacent the inner end of the outer member. The popopen force provided by the booster spring is very useful and desirable in conjunction with heavy vehicle closures such as hatch backs. A further feature is that the outer member is provided with a snap ring which must be bypassed by a stop on the inner member in order to provide a releasable detent for the members in their telescopic outward position. Yet another feature of this invention is that the outer member includes a resilient plastic bushing at its inner end which seats intermediately of the inner member and provides for frictionless movement of the members relative to each other and increases the bending strength of the members.

These and other features will be readily apparent from the following specification and drawings wherein:

FIG. I is a partial rear elevational view of the vehicle body having a closure mounted thereon for movement between open and closed positions and counterbalanced by a telescopic counterbalance according to this invention;

FIG. 2 is an enlarged partially broken away view of the telescopic counterbalance;

FIG. 3 is an enlarged view of a portion of FIG. 2;

FIG. 4 is an enlarged sectional view taken generally along the plane indicated by line 44 of FIG. 2;

FIG. 5 is an enlarged sectional view taken generally along the plane indicated by line 55 of FIG. 2;

FIG. 6 is an enlarged view of a portion of FIG. 2;

FIG. 7 is an enlarged view of a portion of FIG. 2; and

FIG. 8 is an enlarged view of a portion of FIG. 2.

Referring now particularly to FIG. 1 of the drawings, a vehicle body designated generally 10 includes a rear opening 12 which is opened and closed by a hatch or closure 14 which is conventionally hinged to the body adjacent the forward edge of the opening. The closure 14 is counterbalanced during movement between an open position, as shown, and a closed position, not shown, wherein it closes opening 12, by a pair of telescopic counterbalances 16 according to the invention. The counterbalances 16 are respectively pivotally connected at the outer ends thereof to the closure 14 and to the body 10 and are of like construction. Accordingly, only one will be described in detail and it will be understood that the other is the same.

Referring now to FIG. 2, the counterbalance 16 includes an outer or female tubular member 18 and an inner or male tubular member 20. The members can be formed of any conventional material. A spring seat or cup 22 seats within the member 18 adjacent the free or outer end thereof and is secured in place by spaced pairs of dimples 24 which engage the free edge of the cup 22 and also engage underneath the base wall 26 thereof. The member 18 adjacent to the cup 22 is co]- lapsed upon itself and formed into a double walled cupshaped end portion 28. The material of the base wall of this end portion is formed to provide a circular flanged opening 30 which receives a headed plastic grommet 32. The head of the grommet engages the base wall of portion 28 and the split legs of the grommet extend outwardly through the opening 30 and engage under the flange thereof. A conventional headed bolt 34 is received through the grommet and attaches the member 18 to a suitable mounting on the body 10.

As shown in FIGS. 2 and 7, a spring seat or cup 36 is received in the member 20 adjacent the free or outer end thereof and is retained in place by spaced pairs of dimples 38 engaging both the base wall and the free edge thereof. The member 20, adjacent the cup 36, is collapsed upon itself in the same manner as member 18 and formed into a cup-shaped end portion 40. The material of the base wall of this end portion is formed in the same manner as that of end portion 28, into a flanged opening 42 which receives a grommet 44 of the same construction as grommet 32. Grommet 44 receives a bolt 46 which secures the member 20 to the closure 14. Thus, the free or outer ends of the

members

18 and 20 are respectively secured to the body 10 and to the closure 14 for pivotal movement relative thereto as the

members

18 and 20 move-telescopically relative to each other between their telescopic outward and inward positions as the closure moves respectively between open and closed positions. The double walled construction of the end portions 28 and insures that these portions will have adequate strength under all service conditions. The

grommets

32 and 44 obviate all noise problems caused by pivotal movement of the

members

18 and 20 relative to the bolts 34 and 46. Additionally, the

cups

22 and 36 function as dies during the forming of the

end portions

28 and 40.

A main coil compression spring 48 extends continuously through the

members

18 and 20. One end of the spring seats on the base wall 26 of the cup 22 while the other end of the spring seats on the base wall of cup 36 to continually bias the

members

18 and 20 apart or to their telescopic outward position relative to each other. A circular wooden dowel 50 has one end thereof received and retained in a central depression 52 of the member 26. The dowel 50 extends through the spring 48 and controls snaking of this spring relative to the

members

18 and 20 as the spring is compressed when the

members

18 and 20 move to their telescopic inward position. By using a wooden dowel objectionable noise caused by movement of the spring relative to the dowel is reduced to a minimum.

The dowel 50 includes an integral extension 53 of reduced diameter. A coil compression spring 54 surrounds the extension 53 and extends outwardly therefrom for approximately half its length. The spring 54 is retained on the extension by having a coil 56 thereof of reduced diameter received within an annular groove of the extension.

As best shown in FIGS. 2, 3, and 5, the member 18 is provided with three equally spaced rectangular shaped depressions 58 of arcuate cross section. The depressions are formed intermediately of member 18 and are formed by pressing in portions of the wall of this member. The member 20 is provided with an intermediate integral collapsed rib 60 which is engageable with the innermost end walls 61 of the depressions, FIG. 3, when the members are in their telescopically extended position to provide a primary fixed stop limiting telescopic outward movement of the members. Additionally, as shown in FIG. 2, the inner end of member 20 is provided with a flared or cup-shaped terminal portion 62 which is slidable within the member 18 and is of an outer diameter slightly less than the inner diameter of the member. As shown in FIGS. 2 and 6, the inner end of the member 18 is provided with an inwardly opening integral groove 64 which receives the flange 66 of a plastic bushing 68 slidably receiving member 20. Bushing 68 is suitably retained as by lanced inwardly deflected tabs. As previously mentioned. the engagement of the rib 60 with the end walls 61 of the depressions 58 provides a primary fixed stop. Should this primary stop fail for any reason, the engagement of the portion 62 with the bushing 68 provides a secondary stop. Additionally, the sliding engagement of portion 62 with member 18, and the sliding engagement of bushing 68 with member 20 provide spaced support points for the

members

18 and 20 to increase the bending strength of the counterbalance in its various extended positions.

The member 18, as shown best in FIGS. 2 and 4, includes diametrically opposite slots 70 which receive the straight legs 72 ofa generally C-shaped clip 74 partially surrounding the member 18. The legs 72 and the rib 60 provide a releasable detent for the

members

18 and 20 in their fully extended position since the rib must move past these legs during both inward and outward telescopic movement of the

members

18 and 20.

The counterbalance 16 is shown in FIG. 2 in its extended position with the closure 14 in its open position. Spring 48 countcrbalances the closure in this position and engages rib 60 with the end wall 61 of depressions 58. As the closure 14 moves toward its closed position and the

members

18 and 20 telescope inwardly, the rib 60 initially moves past the legs 72 by forcing these legs apart relative to each other in order to release the detent. As the

members

18 and 20 continue to move inwardly of each other, the spring 48 is compressed and counter-balances the weight of the closure 14. When the closure 14 is substantially closed, such as within 13 of closed position, the free end of the spring 54 will engage and seat a central conical seat 76, FIG. 7, of the cup 36 during the final closing movement of the closure 14. In the specific embodiment shown, this engagement will occur at approximately the final l3 of closing movement of the closure 14. Further movement of the closure 14 to its final closed position will then compress the spring 54 to store spring energy. The free end of the extension 53 will be slightly spaced from the seat 76 when the closure 14 is in its closed position. The closure will be retained in this position by a conventional releasable latch.

When such latch is released to open the closure 14, the energy stored in the spring 54 adds to that stored in spring 48 to provide an additional pop-open force aiding the spring 48 in quickly moving the closure to a partially open position wherein the seat 76 moves out of engagement with the spring 54. The closure 14 is counterbalanced for the remainder of its opening movement by the spring 48.

Thus, this invention provides an improved telescopic counterbalance.

What is claimed is:

1. A telescopic counterbalance for a closure movable between open and closed positions relative to a support comprising, in combination, a pair of telescopic annular members movable inwardly and outwardly of each other, means securing the outer ends of the members respectively to the support and the closure, resilient counterbalance means seating between the members to bias the members in a telescopic outward direction and bias the closure to an open position, booster spring means mounted on one of the members, and abutment means mounted on the other member, the booster spring means being normally in a free position and being engaged and compressed by the abutment means only during final inward telescopic movement of the members to provide a pop-open force cooperating with the resilient counterbalance means in initially biasing the closure to a partially open position.

2. A telescopic counterbalance for a closure movable between open and closed positions relative to a support comprising, in combination. a pair of telescopic annular members movable inwardly and outwardly of each other, means securing the outer ends of the members respectively to the support and the closure, main counterbalance spring means seating between the members to bias the members in a telescopic outward direction and bias the closure to an open position, booster spring means mounted on one of the members and located within the main spring means, and abutment means mounted on the other member, the booster spring means being normally in a free position and being engaged and compressed by the abutment means only during the terminal inward telescopic movement of the members to provide a pop-open force cooperating with the main spring means in initially biasing the closure to a partially open position.

3. A telescopic counterbalance for a closure movable between open and closed positions relative to a support comprising, in combination, a pair of telescopic annular members movable inwardly and outwardly of each other, means securing the outer ends of the members respectively to the support and the closure, main spring means within the members seating between the outer ends of the members to bias the members in a telescopic outward direction and bias the closure to an open position, booster spring means, means mounting the booster spring means adjacent the inner end of one olthe members, and abutment means mounted on the other member adjacent the outer end thereof, the booster spring means being normally in a free position and being engaged and compressed by the abutment means only during inward telescopic movement of the members to provide a pop-open force cooperating with the main spring means in initially biasing the closure to a partially open position.

4. A telescopic counterbalance for a closure movable between open and closed positions relative to a support comprising, in combination, a pair of telescopic annular members movable inwardly and outwardly of each other, means securing the outer ends of the members respectively to the support and the closure, spring seat means located adjacent the outer ends of the members internally thereof, main spring means seating on the spring seat means to bias the members in a telescopic outward direction and bias the closure to an open position, an annular member mounted on the spring seat means of one member and extending through the main spring means to adjacent the inner end of said one member to control snaking of said main spring means, booster spring means mounted on said annular member, and abutment means mounted on the other member, the booster spring means being engaged and compressed relative to said annular member by the abutment means during final inward telescopic movement of the members to provide a pop-open force cooperating with the main spring means in initially biasing the closure to a partially open position.

5. A telescopic counterbalance for a closure movable between open and closed positions relative to a support comprising, in combination, a pair of telescopic annular members movable inwardly and outwardly of each other, means securing the outer ends of the members respectively to the support and the closure, resilient counterbalance means seating between the members to bias the members in a telescopic outward direction and bias the closure to an open position, releasable detent means releasably locating the members in a telescopic outward position, booster spring means mounted on one of the members, and abutment means mounted on the other member, the booster spring means being normally in a free position and being engaged and compressed by the abutment means only during final inward telescopic movement of the members to provide a pop-open force cooperating with the resilient counterbalance means in initially biasing the closure to a partially open position.

6. A telescopic counterbalance for a closure movable between open and closed positions relative to a support comprising, in combination, inner and outer telescopic annular members movable between extended and retracted positions relative to each other, means securing the outer ends of the members respectively to the support and to the closure, resilient counterbalance means seating between the members to bias the members to a telescopic extended position and bias the closure to an open position, resiliently deflectable detent means mounted on the outer member, means on the inner member engageable with the detent means and movable therebeyond to provide a releasable detent holding the members in a telescopic extended position against movement to a telescopic retracted position,

booster spring means mounted on one of the members, abutment means mounted on the other member, the booster spring means being engaged and compressed by the abutment means during movement of the members to a telescopic retracted position to provide a popopen force cooperating with the resilient counterbalance means in initially biasing the members to telescopic extended position and biasing the closure to a partially open position, and means on the outer member engageable with the means on the inner member upon movement of the means on the inner member beyond the detent means to provide a stop in the extended position of the annular members.

7. The combination recited in claim 5 wherein the releasable detent means includes spaced resiliently defiectable means on one of the annular members normally located adjacent the other annular member, and means on the other annular member engageable with and movable past the deflectable means in the telescopic outward position of the annular members.

8. The combination recited in claim 5 wherein the releasable detent means includes resiliently deflectable means on one of the telescopic members normally lo cated adjacent the other annular member, and stop means on the other annular member engageable with and bypassing the resiliently deflectable means during outward movement of the annular members relative to each other. the one annular member including second stop means engageable with the first stop means on the other annular member after the first stop means has bypassed the resiliently deflectable means to thereby provide a fixed stop limiting outward telescopic movement of the members.

l l l

Claims

1. A telescopic counterbalance for a closure movable between open and closed positions relative to a support comprising, in combination, a pair of telescopic annular members movable inwardly and outwardly of each other, means securing the outer ends of the members respectively to the support and the closure, resilient counterbalance means seating between the members to bias the members in a telescopic outward direction and bias the closure to an open position, booster spring means mounted on one of the members, and abutment means mounted on the other member, the booster spring means being normally in a free position and being engaged and compressed by the abutment means only during final inward telescopic movement of the members to provide a popopen force cooperating with the resilient counterbalance means in initially biasing the closure to a partially open position.

2. A telescopic counterbalance for a closure movable between open and closed positions relative to a support comprising, in combination, a pair of telescopic annular members movable inwardly and outwardly of each other, means securing the outer ends of the members respectively to the support and the closure, main counterbalance spring means seating between the members to bias the members in a telescopic outward direction and bias the closure to an open position, booster spring means mounted on one of the members and located within the main spring means, and abutment means mounted on the other member, the booster spring means being normally in a free position and being engaged and compressed by the abutment means only during the terminal inward telescopic movement of the members to provide a pop-open force cooperating with the main spring means in initially biasing the closure to a partially open position.

3. A telescopic counterbalance for a closure movable between open and closed positions relative to a support comprising, in combination, a pair of telescopic annular members movable inwardly and outwardly of each other, means securing the outer ends of the members respectively to the support and the closure, main spring means within the members seating between the outer ends of the members to bias the members in a telescopic outward direction and bias the closure to an open position, booster spring means, means mounting the booster spring means adjacent the inner end of one of the members, and abutment means mounted on the other member adjacent the outer end thereof, the booster spring means being normally in a free position and being engaged and compressed by the abutment means only during inward telescopic movement of the members to provide a pop-open force cooperating with the main spring means in initially biasing the closure to a partially open position.

6. A telescopic counterbalance for a closure movable between open and closed positions relative to a support comprising, in combination, inner and outer telescopic annular members movable between extended and retracted positions relative to each other, means securing the outer ends of the members respectively to the support and to the closure, resilient counterbalance means seating between the members to bias the members to a telescopic extended position and bias the closure to an open position, resiliently deflectable detent means mounted on the outer member, means on the inner member engageable with the detent means and movable therebeyond to provide a releasable detent holding the members in a telescopic extended position against movement to a telescopic retracted position, booster spring means mounted on one of the members, abutment means mounted on the other member, the booster spring means being engaged and compressed by the abutment means during movement of the members to a telescopic retracted position to provide a pop-open force cooperating with the resilient counterbalance means in initially biasing the members to telescopic extended position and biasing the closure to a partially open position, and means on the outer member engageable with the means on the inner member upon movement of the means on the inner member beyond the detent means to provide a stop in the extended position of the annular members.

7. The combination recited in claim 5 wherein the releasable detent means includes spaced resiliently deflectable means on one of the annular members normally located adjacent the other annular member, and means on the other annular member engageable with and movable past the deflectable means in the telescopic outward position of the annular members.

8. The combination recited in claim 5 wherein the releasable detent means includes resiliently deflectable means on one of the telescopic members normally located adjacent the other annular member, and stop means on the other annular member engageable with and bypassing the resiliently deflectable means during outward movement of the annular meMbers relative to each other, the one annular member including second stop means engageable with the first stop means on the other annular member after the first stop means has bypassed the resiliently deflectable means to thereby provide a fixed stop limiting outward telescopic movement of the members.